Phẫu Thuật Tai Mũi Họng Và Phẫu Thuật Đầu Cổ

Chapter 12
The Endoscopic Approach
93
usually includes culture-directed antibiotics given for as
long as patients are steadily improving, nasal steroid
sprays, a short course of systemic steroids, and occasion-
ally topical antifungals or antimicrobials. Patients whose
conditions warrant exception from a preoperative trial
of medical therapy include those with impending orbital
complications, those with mucocele, and those with uni-
lateral disease in which a diagnosis is required to evalu-
ate for diseases other than chronic nonspecifi c sinus
infl ammation.
PREOPERATIVE EVALUATION
Following a trial of medical therapy, if the patient
remains symptomatic, then a sinus CT scan should be
performed. Timing of the CT scan is critical. It should
be performed to optimize delineation of irreversible
disease. Sinus CT scans obtained when a patient has a
cold usually show abnormalities that reverse with time.
If a patient has a cold, the sinus CT scan should be
rescheduled to coincide with the symptoms at baseline
after directed medical therapy.
Most surgeons fi nd the coronal sinus CT scan the
most useful. The sinus CT scan is studied at the time
surgery is recommended. If anatomic abnormalities
exist that would be more safely approached with the use
of computerized navigational technology, then this is
arranged. The CT scan image should be available in the
operating room at the time of surgery. Just before
surgery, the sinus CT scan is again reviewed with special
attention to the integrity and symmetry of the lamina
papyracea, skull base, and sphenoid.
Patients should stop taking all aspirin for 10 days
before surgery and all other nonsteroidal anti-infl am-
matories, vitamin E, and ginkgo biloba, which can all
prolong bleeding, 7 days preoperatively. If there is a
history of bleeding with prior surgery or trauma, then
a coagulation profi le is obtained. Profuse bleeding pre-
cludes safe endoscopic visualization and surgery and is
a contraindication to continuation of an endoscopic
dissection.
Preoperatively, patients are counseled regarding
the procedure, risks, and complications. This informed
consent should be detailed and include the following
risks: loss of smell, worsening of symptoms, bleeding,
infection, cerebrospinal fl uid (CSF) leak, and orbital
injury including diplopia and loss of vision. With endo-
scopic surgery directed at symptomatic objective disease,
most series report that at least 85% of patients note an
improvement in symptoms. Patients with nasal polyps
should be apprised that the continued need for medical
therapy postoperatively is common.
Patients with asthma frequently have hyperplastic
sinus disease, which is also known as nasal polyps. Surgery
should be postponed until their asthma is under good
control. This may be facilitated with a preoperative
prednisone taper. Under no circumstances should
intubation be attempted during stage II anesthesia in
an asthmatic patient, because this can provoke a life-
threatening bronchospasm.
SURGICAL APPROACHES
Anesthesia and Patient Position
In the early days of ESS, local anesthesia with heavy
sedation was the norm. It is still possible to operate with
local anesthesia with or without sedation. In the offi ce
setting, revision ESS for patients with chronic hyper-
plastic sinus disease is frequently done using topical
4% Xylocaine alone and the microdébrider. Today,
most patients undergo ESS as an outpatient procedure
under general anesthesia. The surgeon should still
use vasoconstrictors and topical anesthetic agents
even under general anesthesia to minimize blood loss
and general anesthesia requirements. The advantages
of general anesthesia are protection of the airway from
secretions/irrigations and elimination of the possibility
of sudden movement by the patient, causing a surgical
complication. Most practitioners, particularly those
in teaching institutions, currently prefer general
anesthesia.
The patient is positioned supinely under general
anesthesia. For procedures performed in the offi ce
under local anesthesia, a sitting position for the patient
is suitable. Increasingly, surgeons operate with the aid
of a video screen. This allows for teaching and for better
balance and less strained body position for the endos-
copist. In the early days of ESS, all surgery was carried
out with direct visualization through the endoscopes.
Over time, this leads to shoulder and cervical neck
strain in the endoscopist. The endoscopic sinus sur-
geon’s goal is to position his or her body with minimal
or no strain in conjunction with maximal body balance
to most effi ciently perform the procedure. This optimal
positioning can be obtained in either a sitting or a
standing position. We fi nd a table height that is slightly
lower than one’s elbows to be the least fatiguing and
most balanced in manipulating the video endoscope
and instruments. We, like most right-handed endosco-
pists, prefer to stand on the right side of the patient.
The video screen and computer navigational equip-
ment, if used, are placed opposite the surgeon’s eye,
just to the left of the patient’s head. An arm board or
Mayo stand with cushioning towels may be used to
support the left elbow, which controls the endoscope.
A Mayo stand is placed at the head of the bed and is
used to place materials for local injections and pledgets
soaked in oxymetazoline. These pledgets are used for
frequent repacking of the nasal cavity to augment vaso-
constriction throughout the procedure. The anesthesi-
ologist is stationed to the right of the patient and closer
to the midsection and feet of the patient. Defog mate-
rial is placed between the patient’s head and the endos-
copist so that the endoscope can be easily cleaned.
Preparation for Endoscopic Sinus Surgery
Preoperatively the patient’s nose may be anesthetized
and decongested as outlined in the endoscopic approach
to the maxillary sinus. Variations include placement of
synthetic sponges cut into thin strips measuring 3 to
4 cm by 1 cm and soaked in a 50/50 mixture of half

94
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
0.05% oxymetazoline for vasoconstriction and 4% Lido-
caine for topical anesthesia after the patient is under
general orotracheal or laryngeal mask anesthesia. Place-
ment of the pledgets should encompass the middle
meatus, the sphenoid recess, and the mucosa over the
agger nasi cells. Pledgets are removed and replaced
after injecting a total of 5 mL of 1% Lidocaine with
1:100,000 epinephrine divided between the left and
right sides. Injections are placed at the most anterior
attachment of the middle turbinate (sometimes called
the axilla) and the central portion of the middle turbi-
nate. If the posterior ethmoid cells or sphenoid sinus
are to be addressed, then a spinal needle or long dental
needle is used to inject the sphenopalatine artery area,
which lies approximately 1 cm from the posterior edge
of the middle turbinate in the middle meatus.
A transpalatal sphenopalatine block can be per-
formed as an alternative to an endoscopic sphenopala-
tine injection. Before the endoscopic portion of the
procedure, a tongue blade is used to depress the tongue
and allow visualization of the palate, either with a head-
light or the endoscope. The posterior edge of the hard
palate is palpated with the index fi nger, which is then
advanced forward until a subtle 1-cm depression half-
way between the midline and the alveolar ridge at the
level of the second upper molar is felt. Then a needle
is bent, such that the straight shaft is not longer than
12 mm, and is used to inject 2 mL of 1% Lidocaine with
1:100,000 epinephrine. The needle should be directed
slightly toward the occiput and should slip easily into
its full length once the greater palatine canal is entered
(Fig. 12-4). By bending the needle to 12 mm, insertion
of the needle into the sphenopalatine ganglion is pre-
vented. PJ Wormald and colleagues demonstrated a
signifi cant reduction in bleeding and improvement in
visualization in a randomized, blinded, controlled study
using this technique.3
Following these injections, the surgeon scrubs and
the scrub assistant drapes the patient. This allows suffi -
cient time to optimize vasoconstriction from the injec-
tion. If the nasal anatomy is insuffi ciently visualized with
a headlight to allow injection, then the injections are
performed endoscopically after the patient is draped
and the endoscopic equipment is available. Beta block-
ade with metopolol preoperatively results in signifi -
cantly less blood in the surgical fi eld in patients whose
pulse rate was less than 60 beats per minute compared
with placebo-treated patients with higher heart rates.
Whereas blood in the endoscopic fi eld correlates with
heart rate, it does not correlate with mean arterial blood
pressure.4
Most surgeons now prefer to operate using a video
camera. This facilitates the use of bulky instruments
such as microdébriders, which are more easily manipu-
lated if the surgeon’s eye is not against the endoscope
at the same time the surgeon is positioning the micro-
débrider beside the endoscope. The video image allows
the surgeon to operate without undue strain on the
neck, to monitor the surgery of a resident, and to dem-
onstrate technique to others. Finally, video visualization
allows for a second operator to assist whether through
the positioning of the endoscope, liberating both hands
of the surgeon, or by providing instrumentation such
as suction or stabilization of tissue.
Use of Computer-Assisted
Navigational Technology
Computer-assisted navigation allows for precise localiza-
tion of instruments in ESS with the corresponding posi-
tion on a preoperative sinus CT scan. This technology
is particularly helpful in revision sinus cases in which
landmarks are distorted or absent, in extensive nasal
polyposis, for posterior ethmoid disease, and for disease
abutting the skull base, optic nerve, or carotid artery (as
in an Onodi cell). There are several commercial devices
available. Computer-assisted navigational technology
does not replace a thorough knowledge of anatomy.
This technology is not required for most anterior eth-
moidectomy cases.
Anterior Ethmoidectomy (Surgery of the
Bulla Ethmoidalis, Suprabullar Cells, and
Concha Bullosa)
In isolated anterior ethmoid disease, the endoscopic
approach may be limited and consist merely of opening
the ethmoid bulla anteriorly and medially and continu-
ing the dissection posteriorly to include the ostia of the
ethmoid bulla, which opens posteriorly in the retrobul-
lar space. Some surgeons advocate placing an ostial
seeker into the retrobullar space and probing for the
ostia of the ethmoid bulla. Once this is found, the
probe is used to fracture the posterior medial aspect of
the ethmoid bulla cell forward. This fracture provides
a point of purchase for a microdébrider to remove the
anterior, medial aspects of the bulla and connect this
opening with the bulla’s ostia.5 In hyperplastic sinus
disease, the microdébrider is particularly useful for dis-
secting polyps from bony partitions. It may be diffi cult
Figure 12-4. Transpalatal pterygopalatine fossa injection. The
greater palatine canal is halfway between the midline and the alveolar
ridge at the level of the second upper molar. The needle is bent so
that the straight shaft is no longer than 12 mm.

Chapter 12
The Endoscopic Approach
95
in hyperplastic sinus disease to appreciate the level of
the ground lamella, the separation of anterior and pos-
terior ethmoid cells.
In hyperplastic sinus disease, the surgery is no
longer functional, and the goal is to marsupialize the
cavities as widely as possible to facilitate postoperative
irrigations and topical steroids and anti-infectives.
Débriding a portion of the medial aspect of the middle
turbinate with a microdébrider and the adjacent septum
provides two adjacent raw surfaces. Placement of an
absorbable or nonabsorbable pack in the middle meatus
facilitates the contact and ultimately the scarring of the
middle turbinate laterally. This may also be accom-
plished with a transseptal stitch.
The microdébrider should not be used with the
open blade pointed laterally toward the lamina papyra-
cea, because of the danger of inadvertent aspiration
and removal of periorbita and even damage to the
medial rectus muscle. If the microdébrider is used, the
open blade should be directly visualized and pointed
superiorly or medially. The microdébrider should not
be used adjacent to areas of bony dehiscence in the
skull base or orbit. Through-cutting instruments or
plain suction is advocated in these areas.
Concha Bullosa
The presence of a concha bullosa is frequently an inci-
dental fi nding and does not require surgery (Fig. 12-5).
If, however, the concha bullosa is involved with hyper-
plastic mucosal disease, is persistently infected, is
causing airway obstruction, or is limiting exposure to a
diseased frontal, ethmoid, or sphenoid sinus, then it
should be reduced. This is relatively easy with minimal
risks. After injection of anesthetic with vasoconstrictors
into the concha bullosa, a sickle knife is used to make
a vertical incision in the concha. A Grunewald straight
punch is opened and the upper arm is placed in the
vertical incision, with the lower arm outside and below
the concha bullosa. The instrument is closed and an
inferior incision is thus made in the concha. The lateral
aspect of the concha is removed with through-cutting
instruments and the natural ostia of the concha is incor-
porated into the dissection. The microdébrider can be
useful during this portion of the procedure. The verti-
cal and medial portion of the concha is not destabi-
lized. Under no circumstances, with the exception of
tumors, is the superior medial aspect of the middle
turbinate violated, because this can lead to olfactory
impairment.
Posterior Ethmoidectomy
The posterior ethmoid cells drain into the superior
meatus and their anterior extent is marked by the
ground lamella of the middle turbinate. If a complete
anterior and posterior ethmoidectomy is to be per-
formed, then one usually performs a front to back tech-
nique, removing the anterior and then the posterior
ethmoid cells. Because the skull base slopes posteriorly,
with the more posterior aspect being several millime-
ters lower than the anterior skull base as it abuts the
anterior ethmoid cells, perforation of the skull base at
the level of the posterior ethmoids is more common
than at the level of the anterior ethmoids (see Fig. 12-
2). Knowledge and strict attention to this anatomic
detail can prevent this complication.
Because it is unusual to have posterior ethmoid
disease without concomitant anterior ethmoid disease,
in the vast majority of cases an anterior ethmoidectomy
is performed before a posterior ethmoidectomy. Once
an anterior ethmoidectomy is completed (or in the rare
circumstances in which posterior ethmoid access is
desired without anterior ethmoidectomy), the posterior
ethmoids can be safely entered by identifying the
ground lamella of the middle turbinate. This is accom-
plished by advancing the endoscope in the middle
meatus to the most posterior insertion of the middle
turbinate, then withdrawing it anteriorly until the slope
of the insertion of the middle turbinate transitions from
horizontal to vertical. This represents the ground
lamella. Ethmoid cells more posterior to this vertical
aspect will empty above the middle turbinate, in the
superior meatus. By inserting a probe, straight-biting
instrument, or microdébrider at this vertical juncture,
and by targeting the medial inferior aspect of this verti-
cal plane, safe entry into the posterior ethmoid cells is
assured.
Confi rmation of entry into the superior meatus via
an opening through the ground lamella and the poste-
rior ethmoids is accomplished by identifying the ante-
rior aspect of the superior turbinate. Alternatively,
visualization of a Cottle elevator or suction inserted
about 5 cm along the septum and medial to the middle
turbinate can also confi rm that one has opened into
the superior meatus. This orientation can then be used
in proceeding to a sphenoidotomy. A total posterior
#
*
*
Figure 12-5. Note bilateral concha bullosa of the middle turbinate
(*) and even pneumatization (#) of the tip of the uncinate. Also note
the very uncommon anatomic insertion of the uncinate medially,
which potentially allows the frontal sinus to fl ow directly into the
maxillary sinus.

96
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
ethmoidectomy must follow close correlation with the
preoperative CT scan. The skull base in this area is
lower than the anterior ethmoids. Rarely does one iden-
tify the posterior ethmoid artery coursing across the
roof of the posterior ethmoid cells.
Complete dissection of the posterior ethmoids
is facilitated by navigation or close correlation with
the preoperative sinus CT scan, particularly the sagittal
orientation. At the level of the bony roof of the choana,
one is in the sphenoid sinus. A posterior ethmoid
cell that has pneumatized over the sphenoid (an
Onodi cell) is marked by a horizontal septation
overriding the sphenoid sinus on the coronal CT scan
(Fig. 12-6).
The sphenoid sinus is always the cell that is just
above the bony roof of the choana. If there is a cell
above this, then one has an Onodi cell variation. Pneu-
matization of this Onodi cell around the skull base in
the region of the cavernous/carotid system and optic
nerve can put these structures at the same risk surgically
as when this occurs in the sphenoid. Moreover, appre-
ciation of this Onodi cell variation is paramount if one
is performing sphenoid surgery via a posterior ethmoid
dissection.
Keros divided the anatomy of the ethmoid skull
base into three divisions as outlined in Figure 12-7.
Patients with a thin skull base, particularly at the junc-
tion of the lateral lamella and horizontal lamella of the
cribriform are at increased risk for a CSF leak. Monopo-
lar cautery should not be used adjacent to this area
because it may cause a CSF leak.
At the end of the case, the cavity should be irrigated
to remove clots and debris. Meticulous inspection and
removal of all exposed bony spicules speed postopera-
tive healing. Appropriate cultures and pathologic speci-
mens should be obtained. If this is a case with
eosinophilic tenacious green to brown mucous
plugs, then cultures for fungus and special fungal stains
should be requested. If this is a unilateral case, then
it is paramount that pathologic specimens be obtained
for evaluation for inverting papilloma or other type
of tumor.
POSTOPERATIVE MANAGEMENT
The postoperative management of ESS directed to the
ethmoid sinuses is no different from ESS directed
toward the maxillary sinus and there is a wide variation
in follow-up. Packing may or may not be used, and
Figure 12-6. Coronal computed tomography scan demonstrating
bilateral Onodi cells, also known as posterior ethmoid cells, which over-
ride the sphenoid sinus. In this case, the sphenoid sinuses are clear
and the Onodi cells are opacifi ed.
A
I
B
II
C
III
Figure 12-7. Keros classifi ed the depth of the olfactory fossa into
three types, depending on the length of the lateral lamella of the
cribriform plate. A, Keros type I—Olfactory fossa as 1 to 3 mm deep
and the lateral lamella is almost the same plane as our template. B,
Keros type II—Olfactory fossa is 4 to 7 mm deep and the lateral
lamella is longer. C, Keros type III—olfactory fossa is 8 to 16 mm deep
and the ethmoid roof lies signifi cantly above the cribriform plate.
(Modifi ed from Stammberger H: Functional Endoscopic Sinus Surgery: The
Messerklinger Technique. Philadelphia, BC Decker, St. Louis, 1991, p 75.)

Chapter 12
The Endoscopic Approach
97
increasingly the initial postoperative visit is in the fol-
lowing week or two postoperatively, unless patients have
a pack or splint. These are removed immediately post-
operatively to several days postoperatively. We routinely
administer intraoperative antibiotics. There is no evi-
dence that this is protective against the very rare com-
plication of toxic shock syndrome postoperatively.
Postoperative antibiotics should be directed by the sen-
sitivities of preoperative or intraoperative cultures.
Many patients with chronic rhinosinusitis do not have
a bacterial etiology for their chronic rhinosinusitis and
often respond more dramatically to potent anti-infl am-
matories, such as systemic steroids, than to antibiotics.
If the patient has asthma or nasal polyps, we usually
prescribe perioperative and postoperative steroids. In
the operating room, 8 to 10 mg of Decadron is given
intravenously along with an antistaphylococcal antibi-
otic such as cefazolin. Postoperatively, all patients who
are asthmatic and who have nasal polyps are started on
a prednisone taper with an initial dose of 50 to 60 mg
each morning on postoperative day 1. This is tapered
by 10 mg every 1 to 2 days, until the patient is off all
systemic steroids, approximately 2 weeks postopera-
tively. By 2 weeks postoperatively, the postnasal drain-
age associated with sinus surgery is usually improved to
the extent that it no longer endangers the lower airway
by causing bronchospasm. Systemic steroids also provide
the opportunity for the sinus cavities to heal during the
postoperative period without recurrence of polyps.
Aggressive nasal irrigation with saline is initiated on
the fi rst postoperative day, if there is no obstructing
packing. Aggressive irrigation, even with splints, can be
helpful in keeping the nasal cavity and splints free of
blood and debris. Irrigation is continued for a minimum
of several weeks and sometimes indefi nitely. Topical
steroids may be added 10 to 14 days postoperatively and
are usually given after the nasal wash. In refractory
cases, irrigation with 20 to 40 mL of saline is followed
by steroid solution irrigation or nebulization, such as
0.5-mg budesonide respules. Patients are followed up
every week or so until entirely healed. Any scar bands,
cysts, or debris are gently removed endoscopically fol-
lowing topical anesthesia of the nasal cavity with cotton
pledgets impregnated with 4% Lidocaine and a small
amount of oxymetazoline placed for at least 10
minutes.
Patients without hyperplastic nasal mucosa are dis-
charged once they are suffi ciently improved and entirely
healed. Patients with hyperplastic nasal mucosa and
nasal polyps are followed indefi nitely, usually at least
once every 3 to 6 months, because these patients are
usually symptomatically insensitive to regrowth of their
nasal polyps. If regrowth of the polyp is noted early, it
may respond to such maneuvers as intrapolyp injection
of 0.05 mL of steroids (such as triamcinolone acetonide
40 mg/mL) using a spinal needle. Care should be taken
to only inject the avascular polyp, because rapid injec-
tion into vasculature such as is prominent in the turbi-
nate tissue may lead to retrograde embolization into the
retinal artery with associated permanent or transient
visual loss.
References
1. Thanaviratananich S, Chaisiwamongkol K, Kraitrakul S, Tang-
sawad W: The prevalence of an Onodi cell in adult Thai cadavers.
Ear Nose Throat J 82:200-204, 2003.
2. Busaba NY, Salman SD: Ethmoid mucocele as a late complication
of endoscopic ethmoidectomy. Otolaryngol Head Neck Surg
128:517-522, 2003.
3. Wormald PJ, Athanasiadis T, Rees G, Robinson S: An evaluation
of effect of pterygopalatine fossa injection with local anesthetic
and adrenalin in the control of nasal bleeding during endoscopic
sinus surgery. Am J Rhinol 19:288-292, 2005.
4. Nair S, Collins M, Hung P, et al: The effect of beta-blocker pre-
medication on the surgical fi eld during endoscopic sinus surgery.
Laryngoscope 114:1042-1046, 2004.
PEARLS
• The sinus CT scan should be obtained once the
patient has undergone directed medical therapy and
is at symptomatic baseline.
• The sinus CT scan reviewed at the time surgery is
recommended and again in the operating room,
with special attention to the skull base, orbit, and
any bony dehiscences and asymmetries.
• Aggressive postoperative irrigation by the patient
with 20 mL of saline once or twice a day reduces
the amount of postoperative offi ce endoscopic
débridement required.
• The ground lamella can be identifi ed by
endoscopically inspecting the posterior aspect of the
middle meatus and coming forward until the slope
goes from horizontal to vertical. Entering just below
this junction ensures entrance into the posterior
ethmoid cells.
• A posterior ethmoid cell that pneumatizes over the
sphenoid sinus (an Onodi cell) can be adjacent to
the optic nerve or cavernous/carotid complex.
PITFALLS
• If the monopolar cautery is used adjacent to the
cribriform plate at the entry point of the anterior
ethmoid artery, it is likely to cause a CSF leak.
• Use of the microdébrider adjacent to the lamina
papyracea or skull base, especially if there is a bony
erosion or impaired visibility, is likely to irrevocably
destroy extraocular muscles or dura.
• Induction of elective general anesthesia for ESS in
the poorly controlled asthmatic patient may cause
severe bronchospasm and even death.
• Failure to obtain an informed consent regarding
common and rare complications, such as orbital
injury, CSF leak, and loss of smell, makes legal
defense of such complications diffi cult.
• If the middle turbinate is transected close to the
skull base, then loss of olfaction is likely to occur.

98
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
5. Wormald PJ: Surgery of the bulla ethmoidalis and posterior eth-
moids and sphenoidotomy, including three-dimensional recon-
struction of the posterior ethmoids. In Wormald PJ (ed):
Endoscopic Sinus Surgery. Thieme Medical Publishers, 2005.
6. Jang YJ, Park HM, Kim HG: The radiographic incidence of bone
defects in the lateral lamella of the cribriform plate. Clin Otolar-
yngol Allied Sci 24:440-442, 1999.
7. Stammberger
H:
Functional
Endoscopic
Sinus
Surgery:
The Messerklinger Technique. Philadelphia, BC Decker, 1991,
p 75.

Chapter 13
External Ethmoidectomy
Jonas T. Johnson
Ethmoid surgery is usually used in the relief of chronic
sinusitis. A mucosal insult from infection, allergy, or
exposure to a toxic substance results in mucosal edema
with accompanying obstruction of normal sinus ventila-
tion. Retention of secretions, disturbed ciliary function,
and reduced oxygen capacity in the obstructed sinuses
subsequently establishes a milieu that promotes the pro-
liferation of bacteria.
As functional endoscopic sinus surgery has become
the standard approach, the indications for external
ethmoidectomy have declined. However, the external
approach is still useful and may be used to ligate the
ethmoid artery for epistaxis, drain an orbital abscess,
reduce a fracture, expose the optic nerve, or remove a
large osteoma. External ethmoidectomy is still used, by
some surgeons, to provide wider exposure for removal
of malignant tumors and in combination with anterior
fossa approaches in cranial base surgery. All these pro-
cedures may be further enhanced with intraoperative
navigation systems, which are now widely available.
Therefore we have elected to maintain this chapter in
this edition of this text.
Neoplastic transformation of ethmoid tissue is occa-
sionally encountered. Inverted papilloma and a variety
of benign tumors, such as hemangioma and hemangio-
pericytoma, may be encountered. A biopsy of an intra-
nasal lesion in the offi ce should be undertaken
judiciously. Some tumors are vascular in origin and may
bleed profusely. It is also prudent to withhold biopsy
until the required imaging studies have been com-
pleted. This avoids distorting the image and may allow
the surgeon an estimate of the vascularity of the lesion.
Malignant tumors of the ethmoid are rarely encoun-
tered. Squamous cell carcinoma is most frequently
observed; however, a variety of unusual entities such as
adenocarcinoma or melanoma may arise in the ethmoid
sinus. Chronic exposure to tobacco, dust, and industrial
fumes has been implicated in the development of these
lesions.1,2
PATIENT SELECTION
Management of chronic sinusitis with purulent rhinor-
rhea, nasal obstruction, and nasal polyposis may frus-
trate both patient and doctor. Surgery should be
performed only after every effort has been made to
eradicate infection through the administration of anti-
biotics and to reduce tissue edema through the use of
decongestants and topical steroids. Some patients who
have well-documented allergy will benefi t from desen-
sitization. When symptoms fail to respond to medical
management, surgery may be considered. In most
instances, surgical approaches are via an endoscopic
route.
Benign neoplasia of the lateral nasal wall, such as
inverted papilloma, may be removed with either an
open approach or endoscopically. The key to success is
proper preoperative assessment of extent of disease and
total removal of the tumor.3 Occasionally a patient with
a symptomatic osteoma is encountered (Fig. 13-1). A
high-volume lesion may require an external approach.
Patients with concurrent asthma and hypersensitiv-
ity to aspirin represent an especially sensitive subpopu-
lation that may require administration of steroids and
bronchodilators intraoperatively and postoperatively to
prevent exacerbation of their underlying pulmonary
disease. Patients with allergies and asthma tend to have
the most chronic manifestations and are most likely to
experience recurrent nasal polyposis. In this patient
population, surgery should be aimed at the relief of
symptoms, because “cure” is rarely achieved.
PREOPERATIVE EVALUATION
The surgeon must be constantly aware of the proximity
of vital structures to the ethmoid sinus. The most impor-
tant landmarks include the lamina papyracea, which is
the thin plate of bone separating the ethmoid sinus
from the orbit; the fovea ethmoidalis, which separates
99

100
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
the ethmoid sinus from the anterior cranial fossa and
is located at the attachment of the middle turbinate;
and the optic nerve, which is located approximately
4 mm posterior to the posterior ethmoid cell. The crib-
riform plate is located inferior to the roof of the ethmoid
sinus, hence extension of the surgical dissection medi-
ally will result in entrance into the anterior cranial
fossa. All procedures directed at eradication of ethmoid
sinus disease must consider these relationships. When
procedures are required that limit clear identifi cation
of landmarks, use of an intraoperative guidance system
should be considered.
Preoperative assessment should include careful
evaluation of the nasal septum. When signifi cant devia-
tion of the septum is judged to compromise the ability
to effectively undertake a transnasal procedure, concur-
rent nasal septoplasty should be planned.
Preoperatively, patients scheduled for ethmoid
surgery should undergo imaging with computed tomog-
raphy (CT). The coronal plane allows the best assess-
ment of the relationship of the orbit and the fovea
ethmoidalis to the ethmoid. If images are reconstructed
from axial acquisition, they must be of clarity to dem-
onstrate the fi ne detail of the ethmoid roof, middle
turbinate, cribriform plate, and optic foramen. Axial
views may best demonstrate the depth and anteropos-
terior relationships of the frontal sinus and its commu-
nication with the nose. These views may also be helpful
when cannulation of the frontal sinus is anticipated.
The CT scan should be available in the operating room
for intraoperative correlations.
Surgical therapy of neoplasms involving the ethmoid
sinuses is beyond the scope of this chapter. Surgery for
benign neoplasms involving the middle turbinate and
middle meatus may be effectively accomplished endo-
scopically. When wider exposure is deemed necessary,
an external approach may be elected. Often a com-
bined approach with simultaneous visualization through
both the endonasal and external approaches may be
benefi cial in complex cases. This can be undertaken
through either a lateral rhinotomy or a facial degloving
approach, both of which are discussed in Chapter 10.
Similarly, small, well-localized malignancies involving
the middle meatus and turbinate may be removed
through dissection of the lateral nasal wall. Tumors
extending superiorly to involve the fovea ethmoidalis
and skull base should be managed with craniofacial
techniques such as those discussed in Chapter 100.
SURGICAL APPROACHES
Intranasal Polypectomy
Most nasal polyps originate in the middle meatus and
ethmoid sinuses. The sinonasal mucosa has a limited
ability to respond to chronic infl ammation. Edema of
the sinus mucosa results in herniation of a portion of
the mucosa through the ostium into the nose and is
perceived as a “nasal polyp” (Fig. 13-2). These polyps
are most frequently seen in the middle meatus; however,
they may be encountered in the superior meatus and
the sphenoethmoid recess. In advanced cases, the
polyps may protrude into the nasal vestibule.
Nasal polypectomy is most commonly undertaken
using local anesthesia with or without intravenous seda-
tion and monitoring. Some patients have a deviated
nasal septum, which may interfere with adequate expo-
sure and cause incomplete removal of polyps. If this is
recognized before polypectomy, the patient should be
counseled about the need for septoplasty. When the
polyps obscure the view of the septum, the patient
should be told that nasal septoplasty may be necessary.
The polyps and surrounding nasal mucosa can be effec-
tively anesthetized using 100 to 200 mg of cocaine dis-
solved in 8 to 10 mL of saline solution. The solution is
placed on cotton pledgets and inserted in the nose, with
care being taken to advance the pledgets as far as pos-
sible into the middle meatus and sphenoethmoid recess.
After waiting 10 to 15 minutes to maximize both the
anesthetic effect and vasoconstriction, the procedure is
undertaken using nasal speculum, headlight, suction,
and a snare. Use of the intranasal snare allows the oper-
Figure 13-1. The mass displacing the medial aspect of the upper
lid was an osteoma.
Figure 13-2. Chronic sinus disease is frequently associated with the
development of polyps that extend from the sinuses into the nose.

Chapter 13
External Ethmoidectomy
101
ator to divide the polyp as it emerges from the ostium
or to avulse the polyp from the ethmoid sinus. If the
latter technique is used, some measure of ethmoid
débridement will be achieved. When the polyps are
severed at the level of the ostium, the obstruction of the
sinus will naturally persist and early recurrence is fre-
quently encountered. In current practice, the microdé-
brider is often used to remove the polyp as an offi ce
procedure in order to obtain a nasal airway in patients
who do not want or cannot have more defi nitive surgery
for the polyp or the ethmoid sinus.
Intranasal Ethmoidectomy
The principal advantage of intranasal ethmoidectomy
over external ethmoidectomy is the avoidance of a
facial scar. Relative disadvantages are that the intranasal
approach is more diffi cult to learn. Some surgeons have
stated that intranasal ethmoidectomy precludes good
anterior ethmoidectomy. Mosher described the intrana-
sal ethmoidectomy as “the blindest and most dangerous
operation in all surgery.”4 The world has changed since
1929. The availability of modern imaging, magnifi ca-
tion, and endoscopes has dramatically altered sinus
surgery. In a 1979 review of more than 1000 intranasal
ethmoidectomy procedures, however, Freedman and
Kern noted a complication rate of 2.8% without mortal-
ity or blindness.5 Before the adoption of modern
endoscopes, they pointed out that the intranasal eth-
moidectomy could be accomplished safely when the
surgeon has complete knowledge of the anatomy and
understands the surgical technique. This statement is
no less valid today in the era of endoscopic visualization
and intraoperative navigation.
The expanding interest in endoscopic intranasal
ethmoid surgery led to renewed enthusiasm for a clearer
understanding of intranasal and ethmoid anatomy. The
ethmoid sinuses consist of a labyrinth containing 4 to
17 cells, with an average of 9 cells.6 These cells are
arranged along the lateral nasal wall, roughly parallel
to the plane of the middle turbinate, and extend 4 to
5 cm from anterior to posterior, 2.5 cm in height. It is
critical to recognize that while the ethmoid sinuses are
1.5 cm wide posteriorly, the anterior ethmoid may be
only 0.5 cm wide and the relatively narrow anterior
ethmoid represents an area of potential danger in that
penetration of the lateral margin of the ethmoid results
in entry into the orbit.
During examination of the ethmoid labyrinth from
an intranasal perspective, the anterior extent of the
ethmoid labyrinth is approached through the middle
meatus. The draining ostia of the ethmoid cells are
obscured by the uncinate process and the medial pro-
jection of the largest cell the bulla. The uncinate process
is a semilunar structure that begins immediately poste-
rior to the agger nasi cells (anterior attachment of
the middle turbinate) and extends posteriorly in the
middle meatus. Its termination is frequently hidden by
the overhanging middle turbinate. Intranasal surgical
access to the ethmoid cells requires that the uncinate
process be removed so that the extra cells, especially
the agar nasi, can be visualized. Entry into the anterior
ethmoid cell at this point is achieved; however, the
proximity of the lamina papyracea (5 mm laterally)
must be recognized. Removal of the medial, anterior,
and inferior walls of the ethmoid bulla leads to the basal
lamella posteriorly, which separates the anterior from
the posterior ethmoid cells. The basal lamella is
the major attachment of the middle turbinate to the
ethmoid and lamina papyracea. Passing through the
basal lamella in a plane parallel to the middle turbinate
brings the surgeon to the posterior ethmoid cells. The
lateral wall is the lamina papyracea, and dissection
carried laterally exposes and may violate the orbit. Pos-
teriorly the optic nerve is immediately adjacent, and in
well-pneumatized sinuses may actually pass through the
posterior ethmoid sinus.
Intranasal ethmoidectomy may be undertaken with
the patient under either general anesthesia or local
anesthesia supplemented by intravenous sedation and
monitoring. Application of intranasal medication is
necessary with either anesthetic technique in that
control of bleeding requires either topical application
of vasoconstrictor substances or injection. We advocate
the use of oxymetazoline 0.25% on cotton pledgets
employed topically. This is supplemented with lido-
caine 1% with epinephrine 1 : 100,000 injected into the
mucosa of the anterior attachment of the middle turbi-
nate. Powered tissue removal instruments are preferred
over grasping instruments, in that they avoid the tearing
and resultant bleeding that impairs visualization. The
uncinate process is removed and the middle turbinate
can be fractured medially or the anterior half removed
in an effort to afford better exposure of the middle
meatus and ethmoid labyrinth. Landmarks include the
lamina papyracea laterally and the insertion of the
middle turbinate superiorly, which marks the area of
the fovea ethmoidalis and the position of the cribriform
plate. As the operator extends the procedure posteri-
orly, great care must be taken to identify the anterior
face of the sphenoid, which accordingly identifi es
the posterior ethmoid cell. Immediately posterior to
the posterior ethmoid cell and often identifying it is the
optic nerve, which must not be damaged.
The important surgical landmarks for ethmoidec-
tomy are as follows. One should not extend the opera-
tion superior to the attachment of the middle turbinate,
because this attachment marks the level of the fovea
ethmoidalis. The external landmark for the fovea eth-
moidalis is the medial canthus. The operation should
not be extended superior to a line drawn horizontally
between the medial canthi. Similarly, the procedure
should not be extended laterally through the lamina
papyracea. A vertical line drawn through the medial
canthus generally estimates this position. All tissue
should be examined as it is removed. The recognition
of orbital fat as a specimen is an indication of penetra-
tion of the orbit. When placed into normal saline solu-
tion, fat fl oats whereas mucosa sinks.
When powered instruments are employed for eth-
moidectomy, it is essential that the surgeon be acutely
aware of the anatomy to avoid penetration of the orbit

102
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
or central nervous system. Recall that the suction of
powered instruments can draw orbital contents through
bony dehiscence. Evidence of bone dehiscence or
erosion is a relative contraindication to the use of power
débriders. Intranasal tampons are placed at the end of
the procedure.
POSTOPERATIVE MANAGEMENT
Postoperatively, patients are maintained with the head
elevated. A gauze pad taped to the upper lip facilitates
management of small amounts of mucosanguineous
rhinorrhea. Under most circumstances, the intranasal
tampon can usually be removed before patient dis-
charge. The most common postoperative problem is
epistaxis. The risk can be reduced through avoidance
of nose blowing, sneezing with the mouth open, and
avoiding vigorous exercise for 2 to 3 weeks.
The patient is asked to return to the offi ce approxi-
mately 1 week postoperatively, at which time the intra-
nasal structures are carefully inspected, crusts are
removed, and mucoid debris is removed. At this time,
the patient is begun on a course of nasal hygiene
employing intranasal instillation of either saline or
steroid solutions applied with an atomizer. The patient
should return to the offi ce at regular intervals until
mucosalization of the ethmoid sinus is complete. When
synechiae develop between the middle meatus and the
lateral nasal wall, they should be removed to provide
maintenance of good drainage of the ethmoid sinus.
This can be undertaken in the offi ce with topical anes-
thesia and microsurgical instruments.
EXTERNAL ETHMOIDECTOMY
Historically, the external ethmoidectomy procedure
was employed for extensive or recurrent disease, espe-
cially in patients who have had prior intranasal poly-
pectomy
or
intranasal
ethmoidectomy,
because
important landmarks may be distorted by disease or
prior surgery, thereby increasing the risk of revision
intranasal procedures. Patients with involvement of the
ethmoid by aspergillosis or mucormycosis and those
patients with intraorbital infectious complications of
ethmoid sinusitis may require external ethmoidectomy.
The external approach has also been used as a trans-
ethmoidal approach to the pituitary gland, to perform
dacryocystorhinostomy, as access to ethmoid neoplasms,
and to repair cerebrospinal fl uid leaks. Today, these
procedures are performed endoscopically.7 The avail-
ability of endoscopic instrumentation and computer
guidance systems has largely made external approaches
of historical interest.
The external ethmoidectomy procedure allows the
surgeon a three-dimensional assessment of the ethmoid
anatomy, which in turn potentially allows the most
complete exenteration of the ethmoid labyrinth while
under direct visual control, thus affording avoidance of
complications. The principal consequence of the exter-
nal ethmoidectomy technique is the resultant facial
scar.
The procedure is usually performed with the patient
under general anesthesia. Vasoconstriction of the intra-
nasal structures is obtained with topical application of
cocaine or oxymetazoline 0.25%. An incision is made
midway between the nasal dorsum and the medial
canthus. The length of the incision should be approxi-
mately 2 to 3 cm: with one third of the incision superior
to the medial canthus, and two thirds inferior to the
canthus. The incision should be vertical or, if the
surgeon desires to break up the vertical scar, a “stair-
step” (Fig. 13-3). Parabolic incisions should be avoided
A
B
Figure 13-3. A, The external ethmoidectomy incision is made
midway between the medial canthus and the nasal dorsum. B, In
preparation for surgery the lid is closed with a suture and the “stair-
step” incision is marked.

Chapter 13
External Ethmoidectomy
103
Figure 13-4. Elevation is carried posteriorly to expose the anterior
and posterior ethmoid arteries. The frontoethmoid suture line marks
the roof of the fovea ethmoidalis.
Figure 13-5. The lamina papyracea is taken down with punch
forceps, working from anterior toward posterior. Care is taken not to
extend above the frontoethmoid suture line.
in view of the potential for scar contracture and the
development of a pseudoepicanthal fold. The angular
vein is identifi ed and ligated. The incision is carried
through the periosteum. The periosteum is then ele-
vated laterally over the anterior lacrimal ridge and the
lacrimal fossa. Often the base of the lacrimal fossa and
the anterior portion of the lamina papyracea have been
destroyed by disease, and the periosteum must be sepa-
rated from the disease with every effort directed toward
maintaining the integrity of the periorbita. The lacri-
mal sac is identifi ed and elevated out of the lacrimal
fossa. The periosteum of the lamina papyracea is ele-
vated posteriorly. The anterior ethmoid artery is identi-
fi ed in the frontoethmoid suture line 2.0 to 2.5 cm
posterior to the lacrimal crest. The frontoethmoid
suture line and the anterior ethmoid artery serve as
accurate landmarks for the fovea ethmoidalis (base of
the skull). Bone should not be removed superior to this
landmark (Fig. 13-4). The posterior ethmoid artery lies
approximately 12 mm posterior to the anterior ethmoid
and should not be ligated, because it serves as an impor-
tant surgical landmark that is helpful in avoiding enter-
ing the cranial cavity. The posterior ethmoid artery is
encountered in the frontoethmoid suture line. It lies
approximately 5 mm anterior to the optic nerve.
At this point, the ethmoid labyrinth is entered at
the area of the lacrimal fossa (Fig. 13-5). The anterior
two thirds of the lamina papyracea is removed. The
posterior one third is maintained to protect the optic
nerve. The ethmoid mucosa is removed entirely, thus
entering the nasal fossa. The medial landmark at this
point is the middle turbinate, which can be excised.
Care must be taken not to avulse this structure in order
to prevent a cerebrospinal fl uid leak. The dissection is
carried posteriorly through the posterior ethmoid air
cells to the anterior wall of the sphenoid sinus. One of
the potential advantages of the external ethmoidec-
tomy approach is improved exposure of vital structures.
Under most circumstances, the anatomic landmarks
can be observed through the external ethmoidectomy
incision while instruments are introduced through the
nose (Fig. 13-6). Visualizing the surgical fi eld simultane-
ously through an endoscope passed through the nose
is often helpful. In so doing, the intranasal instruments
are passed lateral to the middle turbinate into the
middle meatus (Fig. 13-7). If the sphenoid sinus is
abnormal on imaging studies, the anterior wall of the
sinus is removed and the contents of the sinus drained.
Diseased mucosa and polyps are removed.
The incision is closed in layers, with care taken to
reapproximate the medial canthus to the periosteum
of the nasal bone. Subcuticular layers are closed
with absorbing sutures, following which the skin can
Figure 13-6. Improved visualization can be achieved by passing the
instruments through an intranasal route and observing directly
through the external ethmoid incision.

104
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
Figure 13-7. Intranasal instruments are passed into the middle
meatus; subsequently, they can be observed through the ethmoid
incision.
ecchymosis may be an indication that the orbit has been
violated. Proptosis with decreasing vision requires emer-
gent intervention (lateral canthotomy) to decompress
the orbit and preserve vision (Fig. 13-8).
Patients undergoing surgery of the ethmoid sinus
must remucosalize the operative defect by secondary
intention. During this time, the middle meatus and
ethmoid tend to fi ll with crusts and debris. Frequent
offi ce débridement may be necessary. Patients should
be encouraged to gently blow the nose and irrigate it
with normal saline solution on a regular basis to promote
mucosalization and good healing.
Figure 13-8. Postoperative lid ecchymosis indicates violation of the
orbit. In this case, the injury was entirely preseptal and the orbit was
normal.
PEARLS
• The attachment of the middle turbinates marks the
position of the cribriform plate.
• In situations with altered anatomy, intraoperative
guidance systems may reduce risk.
• The optic nerve is immediately posterior to the
posterior ethmoid cell and may occasionally pass
through it.
• Avoidance of trauma to the nasolacrimal duct will
prevent postoperative epiphora.
PITFALLS
• The most common complication is hemorrhage (less
than 5%).
• Inadvertent entry into the orbit may be associated
with orbital ecchymosis, orbital hematoma, and
compromise of vision.
• Expanding orbital hematoma is an emergency
situation.
• In the presence of decreasing vision, all nasal
packing must be removed. Progression to visual loss
and proptosis is an indication for reexploration,
decompression, and drainage to prevent blindness.
• Violation of the fovea ethmoidalis may be associated
with cerebrospinal fl uid leak. The most common site
of injury is the medial fovea near the anterior
ethmoid artery.
• Postoperative lethargy, headache, or changes in
mental status may be due to hematoma or
pneumocephalus.
be closed with fast-absorbing sutures and Steri-Strips
or subcuticular Proline, and once again employing
Steri-Strips.
POSTOPERATIVE MANAGEMENT
Following external ethmoidectomy, packing is often
not required. If needed, intranasal packing is main-
tained for 24 to 48 hours. Orbital pain, proptosis, or lid

Chapter 13
External Ethmoidectomy
105
References
1. Acheson ED, Cowdell RH, Hadfi eld E, Macbeth RG: Nasal cancer
in woodworkers in the furniture industry. Br Med J 2:587, 1968.
2. Barton RT: Nickel carcinogenesis of the respiratory tract. J Otolar-
yngol 6:412, 1977.
3. Llorente JL, Deleyiannis F, Rodrigo JP, et al: Minimally invasive
treatment of the nasal inverted papilloma. Am J Rhinol 17(6):335-
341, 2003.
4. Mosher HP: The surgical anatomy of the ethmoidal labyrinth.
Trans Am Acad Ophthalmol Otolaryngol 34:376-410, 1929.
5. Freedman HM, Kern EB: Complications of intranasal ethmoidec-
tomy: A review of 1,000 consecutive operations. Laryngoscope
89:421, 1979.
6. Van Alyea OE: Ethmoid labyrinth. Anatomic study with consider-
ation of the clinical signifi cance of its structural characterization.
Arch Otolaryngol 29:881, 1939.
7. Bhargava D, Sankhla D, Ganesan A, Chand P: Endoscopic sinus
surgery for orbital subperiosteal abscess secondary to sinusitis. Rhi-
nology 39(3):151-155, 2001.

Chapter 14
Sphenoid Sinus
Barry M. Schaitkin
The sphenoid sinus is the most posterior of the parana-
sal sinuses. It lies in an area of the cranial base adjacent
to critical neural and vascular structures and thus carries
with it risk to these important structures from disease
sequelae and iatrogenic complications. Because of the
location of the sphenoid sinus and its drainage pathway,
it is isolated from most nasal disorders. The sphenoid
is therefore less often involved with acute and chronic
infection, so surgeons fi nd themselves in this location
less frequently. Surgeons prefer to use image guidance
to navigate in the area of the sphenoid sinus because
they are less comfortable around these critical
structures.
An appreciation of sphenoid anatomy is imperative
for understanding safe surgical approaches to this sinus.
The sphenoid sinus pneumatizes out of the ethmoid
sinus, each sinus independently. Consequently, the
intersinus septum is rarely in the midline, and not infre-
quently this septum or one of the synchondroses within
the sinus attaches to the carotid artery on the lateral
wall (Fig. 14-1).
Anteriorly, the sphenoid sinus communicates into
the nose via its natural ostium. The anterior inferior
projection of the anterior wall of the sphenoid sinus is
called the rostrum, and it is contiguous with the poste-
rior aspect of the vomer. The distance from the nasal
sill to the rostrum is fairly constant at 7 cm, although
gender and racial differences exist (Fig. 14-2).
The sphenoid ostium generally lies superiorly, 3 to
7 mm from the roof of the sinus. It is positioned medial
to the superior turbinate and lateral to the nasal septum,
and these two structures form reliable surgical land-
marks (Fig. 14-3). Laterally and superiorly the sinus is
bounded by the posterior ethmoid sinuses. Sinuses with
extensive pneumatization can extend into the lesser
and greater wings and even into the pterygoid plates
with great variability (Fig. 14-4).
The sphenoid sinus is bordered laterally by the cav-
ernous sinus, carotid artery, optic nerve, and cranial
nerves III to VI. If the anterior clinoid process is pneu-
matized, a carotid optic recess will separate these two
structures. The vidian nerve can be well seen on the
fl oor of the sinus on coronal radiographs. Superiorly,
the roof of the sphenoid sinus forms the planum sphe-
noidale, which makes up the portion of the midline
skull base immediately posterior to the cribriform
plates.
Posteriorly, the sinus is indented to a variable
degree by the pituitary gland, depending on the type
of sphenoid pneumatization. The posterior boundary
of the sphenoid is the anterior wall of the clivus. The
pons and brain stem with the accompanying midline
basilar artery lie directly posterior to the highly pneu-
matized sinus in this location.
PATIENT SELECTION
Patients with sphenoid pathology may have no symp-
toms, with an abnormality noticed incidentally on
imaging for a different purpose. This is particularly true
of mucoceles and fungus balls. When they are sympto-
matic, patients may complain of a headache that is
classically vertex in location. Invasive processes in the
sphenoid sinus may result in dysfunction of the adja-
cent cranial nerves.1,2
Symptomatic lesions present no diffi culty in surgi-
cal planning, and at least a biopsy specimen is usually
obtained. It is often more diffi cult to handle an asymp-
tomatic lesion. Silent lesions may require extirpation.
An asymptomatic lesion that is treated nonoperatively
should be monitored with subsequent imaging.
Cerebrospinal fl uid (CSF) rhinorrhea can originate
from within the sphenoid. Patients may have a CSF leak
postoperatively as a result of bone erosion or spontane-
107

108
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
ously through congenital dehiscences in the skull
base.
Defi nite indications for surgery include the compli-
cations of sphenoid sinusitis, expanding mucoceles,
allergic or invasive fungal sinusitis, and suspected neo-
plasms. As with all sinuses, patients are candidates for
surgery if they have failed reasonable medical therapy
for infl ammatory sinus disorders.
Preoperatively, patients should undergo detailed
offi ce nasal endoscopy for evaluation of the anatomic
confi guration and to obtain accurate endoscopic
samples for culture. Computed tomography (CT) scan-
ning is mandatory for surgical candidates and should
include both axial and coronal views to document the
relationship of the pathology to the optic nerve and
carotid artery, with particular attention paid to the
amount of bone covering the vital structures. Magnetic
resonance imaging (MRI) is useful if the pathology
abuts the brain or orbital contents, but it is usually
complementary and not a substitute for CT.
Infl ammatory disease is the most common indica-
tion for sphenoid sinus surgery. Sphenoid sinusitis
usually occurs in the setting of pansinus involvement.
Isolated sphenoid sinus disease is rare, but acute and
chronic infl ammatory disease is possible. Untreated,
infl ammatory disease can lead to meningitis, abscess
formation, and cavernous sinus thrombosis with cranial
nerve involvement or blindness.
Other diseases common to all of the sinuses can
involve the sphenoid as well. Mucoceles, polyps, fungus
balls, and retention cysts can develop. Benign and
malignant tumors, both primary and metastatic, may
occur. Both invasive and noninvasive sphenoid fungal
disease can develop in immunocompetent as well as
immunocompromised hosts.
Primary tumors arising within the sphenoid are very
rare. However, the sphenoid sinus may be secondarily
involved by extension of tumors arising outside the
sinus proper, such as in the ethmoid or nasopharynx.
Benign tumors of the pituitary gland may expand to
involve the sphenoid sinus, and primary bone neo-
plasms such as osteogenic sarcoma, chondrosarcoma,
or chordoma can be manifested as a mass in the sphe-
noid sinus. The most common malignant tumors of the
Figure 14-1. Coronal computed tomography scan with the intersi-
nus septum attached to the right carotid artery (arrow).
11 cm
9 cm
7 cm
30

Figure 14-2. Diagram demonstrating a beaded probe anterior to
the anterior wall of the sphenoid sinus. (Redrawn from Bailey BJ:
Approaches to the sphenoid. In Bailey BJ, Johnson J, Kohut R, et al [eds]:
Head and Neck Surgery—Otolaryngology. Philadelphia, JB Lippincott,
1993.)
posterior
ethmoid
septum
Figure 14-3. Position of the right sphenoid ostium medial to the
superior turbinate. Asterisk, on the right superior turbinate; plus sign,
on the right sphenoid ostium.
Figure 14-4. More extensive lateral sphenoid pneumatization
(arrow).

Chapter 14
Sphenoid Sinus
109
sphenoid sinus are metastatic disease from the kidney,
lung, and breast. Aneurysms of the basilar artery can
erode into the sphenoid sinus and appear as a mass in
the sinus, and aneurysms of the internal carotid artery
have also been encountered.
PREOPERATIVE PLANNING
The majority of surgical procedures on the sphenoid
sinus are performed either as part of endoscopic sinus
surgery for chronic sinusitis or as an approach to the
sella. Decisions regarding opening the sphenoid in the
context of sinus surgery are complex. All the factors
that weigh in on whether someone is a candidate for
endoscopic sinus surgery must be considered. Preoper-
atively, patients should undergo thorough nasal endo-
scopic examination to aid in surgical planning. Careful
documentation of the presence of septal or other ana-
tomic limitations will dictate the choice of surgical
options, as will the size of the sphenoid and the location
of the pathology within the sinus.
Before surgery, the surgeon must select the optimal
approach. In general, if performing a total ethmoidec-
tomy, one may continue to dissect lateral to the middle
turbinate as an approach to the sphenoid. In cases of
isolated sphenoid disease, the surgeon may proceed
medial to the middle turbinate directly to the sphenoid
os (Fig. 14-5). Patients with midline pathology, such as
pituitary tumors, can be approached either directly with
the endoscope or by using a transseptal approach (see
Chapter 103).
CT scanning is mandatory in preoperative plan-
ning. Although coronal CT is standard for all endo-
scopic sinus surgery, axial CT is useful for preoperative
planning of sphenoid sinus surgery. At this time, com-
puterized navigation-assisted surgery for sphenoid sinus
surgery is performed on a case-by-case basis. MRI is
useful if there is any question regarding the interface
between the sinus and the brain or orbit, but it does
not duplicate the visualization of bony detail provided
by CT scans.
CT scans should be reviewed several times preop-
eratively and should always be displayed in the operat-
ing room. Particular attention should be paid to the
presence of bone erosion, the location of vital struc-
tures, and the thickness of the bone covering them. The
position of the intersinus septum and any incomplete
bony septations should be noted. The scans should be
reviewed for the presence of posterior ethmoid pneu-
matization that extends posterior and lateral to the
sphenoid (Onodi cell formation), which puts the optic
nerve at risk.
If using computerized navigation, the location of
known landmarks should be confi rmed before proceed-
ing with entry into the sphenoid. There is still a use for
cross-table fl uoroscopy when entering the sphenoid if
there is any doubt about the anatomy or if the com-
puterized navigation instrumentation fails or is not
available.
SURGICAL APPROACHES
Transseptal Approach
The transseptal route can be approached via a transna-
sal or a sublabial incision. The nasal approach to the
septum may require the use of a limited lateral rhinot-
omy (alotomy), or it can proceed through an external
rhinoplasty approach. We prefer the sublabial incision
for transseptal surgery because of greater exposure
despite the greater distance involved and the need for
oral incisions.3 This midline approach is ideal for pitu-
itary surgery, but it is also useful for other midline
pathologies when surgery on the other sinuses is not
required.
Positioning of the patient depends on the proce-
dure and surgical preferences. The nose is decongested,
and local anesthesia with epinephrine is injected to
hydrodissect the septal mucosa off the cartilage and
bone. The sublabial area is injected if surgery will
include this exposure. The eyes are left undraped in all
procedures in which they might be at risk.
A headlight is required for the initial portion of the
procedure. The septum is approached through a stan-
dard left anterior hemitransfi xion incision, and ante-
rior and posterior tunnels are raised on the left. These
tunnels are converted into a fl oor-of-the-nose tunnel by
sharply dividing the decussating fi bers separating the
two tunnels, and the left mucosal fl ap is completed. The
cartilage is left attached to the right mucoperichon-
drium. The bone-cartilage junction is breeched and a
posterior mucosal fl ap on the right is used to isolate the
bony septum. The cartilage is then elevated out of the
maxillary crest and the mucosa is dissected away from
the fl oor of the nose on the right. At this point the
upper lip is retracted with two army-navy retractors held
by an assistant (Fig. 14-6). A gingivobuccal sulcus inci-
sion from premolar to premolar is made with electro-
cautery down to bone. A cuff of mucosa above the teeth
must be preserved to allow closure at the conclusion of
the procedure. All soft tissue is elevated off the bone
and the previous nasal tunnels are entered. A small
amount of soft tissue is left on the anterior nasal spine
to facilitate repositioning of the septum at the conclu-
Figure 14-5. Endoscopic view of the left sphenoid ostium and supe-
rior turbinate (arrow).

110
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
sion of the procedure (Fig. 14-7). When coming over
the piriform aperture into the fl oor of nose, the angula-
tion of a Woodson elevator can facilitate this dissection
and avoid tearing the mucosa.
Some surgeons do the entire approach via sublabial
incisions without intranasal tunnels; however, if one
does a great deal of septoplasty, it may expedite the
procedure to perform the nasal portion fi rst.
When the elevation has reached the posterior limit
of the septum, the bone will begin to move laterally.
The bone of the posterior septum is removed, with
Figure 14-6. Gingivobuccal incision. (Redrawn from Lee KJ: The sub-
labial transseptal transsphenoidal approach to the hypophysis. Laryngoscope
88[Suppl 10]:1-65, 1978.)
A
B
Figure 14-7. Freeing the nasal spine. Although the spine can be
removed, it is easiest to leave it attached to the septum to facilitate
replacement at the end of the procedure. (Redrawn from Lee KJ: The
sublabial transseptal transsphenoidal approach to the hypophysis. Laryngo-
scope 88 [Suppl 10]:1-65, 1978.)
Figure 14-8. A and B, Insertion of a Hubbard or Hardy self-retain-
ing speculum between the blades of a Killian speculum. It is impor-
tant that the vomer be straddled by the speculum as it is inserted. (A,
Redrawn from Petcu MS, Sasaki CT: Pituitary tumors. In Pillsbury HC III,
Goldsmith MM III [eds]: Operative Challenges in Otolaryngology—Head and
Neck Surgery. Chicago, Year Book, 1990, pp 160-175.)
extreme care paid to its articulation with the skull base.
Exposure of the anterior face of the sphenoid is facili-
tated by inserting a Hardy self-retaining speculum (Fig.
14-8). Care must be taken to ensure that the blades of
the speculum straddle the remaining attachment of the
posterior septum to the vomer without injuring the
mucosal fl aps. The speculum is advanced slowly and the
blades are opened once the posterior limit is reached.
Care must be taken to not entrap the mucosa between
the end of the speculum and the sphenoid rostrum or
perforation of the posterior fl ap can occur during bone
removal. These fl aps will be relied on if CSF is encoun-
tered or the sinus is obliterated. The point of entrance
into the sphenoid sinus is based on the anatomy of the
rostrum, with the sphenoid sinus frequently being
entered through the ostium or a natural dehiscence.

Chapter 14
Sphenoid Sinus
111
The bone of the front wall of the sphenoid is removed
maximally with Kerrison punches for exposure (Fig.
14-9). The speculum is positioned so that blades are not
allowed to enter the sinus.
An operating microscope with a 300- or 350-mm
lens is brought into position for most pituitary cases,
but a nasal endoscope can also be used. The mucosa
within the sinus is generally respected and preserved
unless obliteration is planned. Removing it causes
annoying bleeding.
After the neurosurgeon completes the pituitary
procedure, the incisions can be closed. Cartilage or
bone can be used to reconstruct the sella if necessary.
Any CSF leakage must be managed with tissue grafts.
The sphenoid is obliterated with fat only if necessary,
but the mucosa must be completely stripped in this case
to prevent mucocele formation. The speculum is
removed and the fl aps are approximated to each other
with a quilting absorbable suture. The cartilaginous
septum is attached to the nasal spine (if left in place by
the neurosurgeons) with clear nylon. The gingivobuc-
cal incisions are closed with 3-0 chromic suture. Splints
and packing are often used, but this author does not
generally use either for these cases, which greatly
increases patient comfort. If an obliteration was per-
formed, packing is placed to support the posterior
septal fl aps against the sphenoid tissue.
Transnasal Approach
Endoscopic approaches are performed either medial to
the middle turbinate in direct fashion or lateral to the
turbinate through the ethmoid.4-6 The landmarks for
both will be described.
Endoscopic surgery requires maximal deconges-
tion of the nose to facilitate exposure and minimize
bleeding, which can soil the telescope. Decongestant
nasal spray is started 30 minutes before the patient
comes to the operating room and continues during the
preparation period. Local injections for a direct route
use epinephrine-containing local anesthesia delivered
through a spinal needle. Sphenoid surgery in our center
is performed as a two-surgeon technique with the assis-
tant holding the telescope and the surgeon holding an
instrument and a suction device. The middle turbinate
is gently lateralized to get it out of the way and to avoid
any traumatic bleeding that might soil the lens. A 0-
degree scope works well for the approach. The superior
turbinate is located. The entry will proceed between the
superior turbinate and the septum. The natural ostium
can often be located in a far superior location. On occa-
sion, removal of the inferior third of the superior tur-
binate facilitates location of the os.
As is the case when opening any sinus ostium, one
should try to preserve mucosa 180 degrees around the
ostium. For sphenoid surgery this is usually most con-
veniently done by opening the sinus inferior to the
ostium and protecting the mucosal rim superiorly. Up-
and down-biting Kerrison 1- and 3-mm forceps facilitate
removal of the bone of the front face of the sphenoid
sinus to deal with most pathologies. In patients in whom
the ostium cannot be identifi ed, the arch of the choana
is used as a reference point. The surgeon can safely
enter the sphenoid sinus between the superior turbi-
nate and the septum 1.5 cm above the arch in a well-
pneumatized sphenoid. Axial and coronal CT scans
must be reviewed before entry.
In approaching midline pathology, as in endo-
scopic pituitary surgery, the surgeon may choose to
open the sphenoid completely from one side of the
nose. In such cases the posterior septum is incised with
a sickle knife, and through-cutting forceps are used to
remove the posterior septum. The rostrum is removed
and wide pituitary access is achieved. The surgeon
should be very careful when enlarging the front wall of
the sphenoid inferiorly. The choanal branch of the
sphenopalatine artery is often violated, but it may or
may not bleed immediately. We prefer to look for the
artery and use monopolar suction cautery on the mucosa
on either side of the sphenoidotomy, even in the
absence of frank bleeding, to avoid a vessel in spasm
opening later. No closure is required for these proce-
dures, and no packing is used unless a CSF leak repair
has been performed.
In the event of concomitant ethmoid surgery, total
endoscopic ethmoidectomy is fi rst performed. The
sphenoid can then be located in two ways. Parsons
described use of the “ridge” as a landmark for entry into
the sphenoid. This ridge represents the attachment of
the superior turbinate, and by dislocating this turbinate
in an inferior and medial direction, its attachment is
seen as a ridge. Safe surgical entry can be accomplished
inferior and medial to the ridge.7
Alternatively, the posterior aspect of the basal
lamella can be removed. By making a window at the
position where the middle turbinate curves laterally to
attach to the orbit, the superior turbinate can easily be
visualized through the ethmoid sinus. At this point the
procedure looks exactly like a direct entry. The inferior
aspect of the superior turbinate can be removed and
the natural ostium of the sphenoid can be found directly
between the superior turbinate and septum. There are
two advantages of going to the sphenoid through the
Figure 14-9. Enlarging the sphenoidotomy with a bone punch.
(Redrawn from Petcu MS, Sasaki CT: Pituitary tumors. In Pillsbury HC III,
Goldsmith MM III [eds]: Operative Challenges in Otolaryngology—Head and
Neck Surgery. Chicago, Year Book, 1990, pp 160-175.)

112
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
ethmoid instead of directly: one is to avoid a bloody,
relatively tighter tunnel of exposure, and the other is
to avoid lateral force on the middle turbinate after
ethmoidectomy with the potential to disrupt the stabil-
ity of the turbinate (see Videos 14-1 and 14-2).8
Independent of which type of entry the surgeon
uses, extreme care should be taken in extracting any
sphenoid pathology. A combination of suction and irri-
gation facilitates the extraction of inspissated secretions
and fungal elements. Soft tissue masses are gently
removed with forceps. Powered instruments should be
used sparingly, perhaps only on the fl oor of the sinus,
and in our hands are not used at all. The structures of
the lateral nasal wall are vital and vulnerable and should
be respected at all cost, particularly when dealing with
infl ammatory disease; the surgeon should leave infl am-
matory disease in place rather than aggressively remov-
ing it when it overlies critical structures. The goal of
aeration and drainage should be kept in mind and
mucosa preserved as much as possible.
POSTOPERATIVE MANAGEMENT
Patients undergoing surgery on the sphenoid sinus are
managed similarly for all indications. Saline irrigation
is the mainstay. For the majority of pathologies, mucosa
is left intact at the surgical margins and healing is
prompt. Minor endoscopically guided débridement
may be indicated if the mucosa has been removed for
greater access or exposure. Gentle care is required
when instruments are within the sinus whether intraop-
eratively or postoperatively.
COMPLICATIONS
Because of the possibility of dehiscence of the carotid
artery and optic nerve, these structures are vulnerable
on the lateral wall of the sphenoid. It is better to leave
infl amed tissue on these structures than to place them
at risk. Injury to the optic nerve cannot be repaired.
If the carotid is violated, the nose is promptly
packed with large amounts of packing material. Blood
transfusion may be necessary and the patient should be
taken immediately to the angiography suite. Balloon
occlusion is used to control bleeding but has a signifi -
cant attendant risk of neurologic complications.
Leakage of CSF should be dealt with as per other
locations. The defect must be appreciated and the
mucosa stripped around it. An appropriate tissue graft
is designed. An overlay technique is acceptable for
smaller defects, but those larger than 1 cm should be
treated with an underlay graft. Tissue glue and addi-
tional grafting can be placed below the fi rst graft and
supported with packing, which starts with absorbable
agents.
CONCLUSION
Approaches to the sphenoid sinus can be transeth-
moidal, transnasal, or transseptal. The surgeon’s expe-
rience and the location of the pathology dictate the
choice of procedure for each individual patient. Endo-
scopic techniques will continue to further decrease the
frequency of use of the transseptal approach. High-
quality preoperative images must be reviewed carefully
and should be displayed in the room at the time of
surgery. Dissection within the confi nes of the sphenoid
is dangerous and should be restricted to the inferior
and medial aspects when possible.
PEARLS
• The approach to the sphenoid sinus is usually
selected on the basis of preoperative imaging and
endoscopy.
• Careful attention to imaging allows avoidance of
injury to neural and vascular structures.
• Removal of infl ammatory disease should never put
vital structures at risk.
• Powered instrumentation should never be used
within the sphenoid sinus.
• Intraoperative control of the choanal branch of the
sphenopalatine artery will avoid postoperative
bleeding diffi culties.
References
1. Hadar T, Yaniv E, Shvero J: Isolated sphenoid sinus changes—
history, CT and endoscopic fi nding. J Laryngol Otol 110:850-853,
1996.
2. Wang ZM, Kanoh N, Dai CF, et al: Isolated sphenoid sinus disease:
An analysis of 122 cases. Ann Otol Rhinol Laryngol 111:323-327,
2003.
3. Lee KJ: The sublabial transseptal transsphenoidal approach to the
hypophysis. Laryngoscope 88(Suppl 10):1-65, 1978.
4. Smith WC, Boyd EM, Parsons DS: Pediatric sphenoidotomy. Oto-
laryngol Clin North Am 29:159-167, 1996.
5. Metson R, Gliklich RE: Endoscopic treatment of sphenoid sinus-
itis. Otolaryngol Head Neck Surg 114:736-744, 1996.
6. Kieff DA, Busaba N: Treatment of isolated sphenoid sinus infl am-
matory disease by endoscopic sphenoidotomy without ethmoidec-
tomy. Laryngoscope 112:2186-2188, 2002.
7. Parsons DA: A safer entry to the sphenoid sinus during FESS in
children. Oper Tech Otolaryngol Head Neck Surg 5:43-44, 1994.
8. Gibbons MD, Sillers MJ: Minimally invasive approaches to the
sphenoid sinus. Otolaryngol Head Neck Surg 126:635-641, 2002.
PITFALLS
• Removing the mucosa of the sphenoid sinus
circumferentially about the sphenoid ostia runs the
risk of ostium stenosis.
• If using computerized navigation, check the device
for accuracy on a known anatomic structure before
entering the sphenoid.
• Have a plan in place for the unlikely complication of
carotid artery rupture.
• Many patients with headaches have incidental
sphenoid pathology, and the patient should be
informed that correction of the abnormality on the
scan may not be the solution to the headache
problem.

Frontal Sinus
Chapter 15
External Approaches to the Frontal Sinus
Barry M. Schaitkin and Ricardo L. Carrau
The frontal sinus develops as an extension of the ante-
rior ethmoid cells in the fi rst 3 years of life. Pneumatiza-
tion continues through childhood until the frontal
sinus reaches its full dimensions by the second decade
of life, although 4% of frontal sinuses fail to develop
entirely.1,2 Pneumatization of the sinus is highly vari-
able, as are its dimensions; however, the average adult
frontal sinus is approximately 28 mm high, 24 mm wide,
and 20 mm deep.2 The frontal sinus is usually asymmet-
ric.2 It communicates with the nasal cavity through the
nasofrontal recess, which drains into the middle meatus
in a variable relationship with the hiatus semilunaris.
The diameter of the nasofrontal recess varies from 2 to
10 mm.3
The most frequent pathology of the frontal sinus is
infl ammatory in nature and it most commonly arises as
a result of obstruction of the nasofrontal recess, which
often refl ects infl ammatory disease in the anterior
ethmoid sinuses and ostiomeatal complex.4 Benign
tumors such as inverted papillomas, mucoceles, and
osteomas are occasionally encountered (Fig. 15-1).
True neoplasms of the frontal sinus arising from epi-
thelial cells or mucous glands situated in the mucosa
are quite rare.5 It may, however, be involved by tumors
that arise in adjacent areas of the sinonasal tract, skull
base, or orbit. The frontal sinus is also an infrequent
site of metastatic carcinoma.
PATIENT SELECTION
Frontal sinusitis frequently occurs in the setting of acute
upper respiratory infection or seasonal or chronic rhi-
nitis.6 Acute frontal sinusitis is most often associated
with pain that is characterized as dull or pressure-like
and localized to the frontal, supraorbital, or retro-
orbital areas. Unilateral involvement of the frontal sinus
may give rise to unilateral symptoms. Associated nasal
congestion and purulent rhinorrhea suggest pansinus-
itis. Initial therapy should be directed at eradication of
the pathogen and improvement of drainage, which can
most effi ciently be achieved through the administration
of appropriate antibiotics and the use of decongestants.
In the setting of pansinusitis, improved drainage of the
frontal sinus can be expected to occur with resolution
of the infl ammatory component in the area of the fron-
tonasal recess, especially the anterior ethmoid air cells.
In contrast, isolated frontal sinusitis is often a refl ection
of more serious obstruction of the frontal sinus and has
the potential for both orbital and intracranial complica-
tions.7-10 Patients with isolated symptomatic frontal
sinusitis (pain, fever, and headache) will benefi t from
hospitalization and the administration of intravenous
antibiotics and corticosteroids. If symptoms fail to
improve within 24 to 72 hours or if there is progression
of the disease as characterized by signs or symptoms,
surgical intervention is indicated. Patients with orbital
or intracranial complications of frontal sinusitis should
have the sinus drained promptly.
PREOPERATIVE PLANNING
The diagnosis of frontal sinusitis should be confi rmed
radiographically. The classic conventional radiographic
fi nding in acute frontal sinusitis is demonstration of an
air-fl uid level (Fig. 15-2) or complete opacifi cation. A
computed tomography (CT) scan provides better assess-
ment of the confi guration and contents of the sinus by
demonstrating the important anatomic relationships to
the orbit and anterior cranial fossa, as well as improved
understanding of the anatomy of the nasofrontal recess
and the other paranasal sinuses (Fig. 15-3).
113

114
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
A
B
Figure 15-1. A, Anteroposterior
radiograph demonstrating a large
osteoma of the frontal sinus. B,
Lateral radiograph confi rming the
position of the osteoma in the
frontal sinus. This lesion was deemed
inappropriate
for
endoscopic
removal, and an open procedure
through an osteoplastic fl ap was
performed.
Figure 15-2. Anteroposterior radiograph demonstrating an air-
fl uid level in the frontal sinus. Note that the patient has left
pansinusitis.
SURGICAL TECHNIQUES
Trephination
Trephination of the frontal sinus follows the same prin-
ciples involved in drainage of an abscess found in soft
tissue (Figs. 15-4 and 15-5). The procedure may be
carried out under local or general anesthesia, depend-
ing on the condition of the patient and the personal
preference of both the patient and surgeon. A 1-cm
brow incision is made medial to the supraorbital nerve.
The periosteum is elevated to expose the anterior wall
of the frontal sinus. An estimate of the depth of the
frontal sinus and its relationship to the orbit and ante-
rior cranial fossa can be obtained through review of the
CT scan. A cutting burr is used to drill into the frontal
sinus. The position of the opening trephine must be
properly planned to avoid inadvertent entry into the
anterior cranial fossa. Several commercial trephination
sets are currently available. They provide the ability to
perform limited trephination through a very small inci-
sion. The same precautions apply, however.11,12
Purulent secretions drained from the sinus should
be submitted for Gram stain, culture, and sensitivity
testing. The sinus can be then copiously irrigated with
normal saline solution containing broad-spectrum anti-
biotics. A catheter is then introduced through the tre-
phine into the frontal sinus and brought out through
the skin incision to permit irrigation of the sinus cavity
postoperatively. The skin is closed around the catheter,
which is then sutured to the adjacent skin. An eye patch
may be applied if necessary.

Chapter 15
External Approaches to the Frontal Sinus
115
A
B
Figure 15-3. A, Coronal com-
puted
tomography
(CT)
scan
demonstrating right-sided frontal
opacifi cation with involvement of
the anterior ethmoid sinus. B, Axial
CT scan displaying the air-fl uid level
in the right frontal sinus.
Figure 15-4. Trephination is performed through an incision made
in the medial aspect of the brow. The fl oor of the frontal sinus is
exposed and a drill is used to drain the sinus. The lateral wall of the
nasal frontal recess is then removed to provide communication
between the frontal sinus and the middle meatus.
Figure 15-5. Trephination of the frontal sinus for acute frontal
sinusitis.
Postoperative Management
Trephination relieves acute frontal sinusitis that fails to
resolve with medical therapy. The strategy is to relieve
the pressure symptoms, drain the purulent exudate,
and then completely eradicate the infection with intra-
venous antibiotics. The mucosa of the nasofrontal recess
is expected to return to its normal condition with res-
toration of normal sinus drainage. This process can be
enhanced by irrigation of antibiotics solution through
a catheter inserted into the frontal sinus. It is often
useful to include 0.05% oxymetazoline to further
decongest the mucosa, thereby promoting drainage.
When repeated irrigation of the sinus results in free
fl ow of the irrigating solution through the nose, the
catheter can be removed and the trephination allowed
to close by secondary intention. Restoration of function
in the nasofrontal recess frequently takes 7 to 10 days.
Failure to respond may be an indication for defi nitive
surgery to correct irreversible obstruction of the naso-
frontal duct.
Frontal Sinusotomy with Fat Obliteration
Frontal sinusotomy provides a wide exposure that allows
complete exenteration of all the mucosa of the frontal
sinus while preserving its normal external contour.13-16
At the completion of the procedure, the nasofrontal
ducts are obliterated with autologous tissue such as
muscle, and the sinus is obliterated with abdominal
fat.
A template of the frontal sinus is designed from a
preoperative anteroposterior radiograph taken at 6 ft

116
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
of distance (Caldwell’s view) (Fig. 15-6). Because most
patients have asymmetric frontal sinuses, it is important
to properly identify the left-right orientation. Precise
mapping of the frontal sinus may be performed with a
surgical navigation device to avoid some of the prob-
lems related to a Caldwell view template.
The anterior frontal bone can be exposed with a
bicoronal incision placed above the hairline (Fig. 15-7).
A gull-wing incision is cosmetically inferior and usually
divides the supraorbital nerve, which results in trouble-
some paresthesias and numbness of the forehead post-
operatively. The bicoronal incision affords a completely
hidden scar without sensory denervation. The principal
limitation is cosmetic and only in patients with male
pattern baldness. Temporary tarsorrhaphy is performed
as a safety measure.
The frontal bone should be widely exposed down
to the supraorbital rims while taking care to avoid injury
to the supraorbital nerves. With the supraorbital rims
used as a landmark, the template is used to outline the
confi guration of the frontal sinus. Alternatively, the
boundaries of the frontal sinus can be marked under
the guidance of a navigation device. Leaving the peri-
osteum attached to the bone (osteoplastic fl ap) is
unnecessary for survival of the frontal bone and ruins
the possibility of using a pericranial fl ap (Fig. 15-8).
A reciprocating, sagittal, or oscillating saw may be
used to bevel the osteotomy while taking care to ensure
that the frontal sinus and not the cranial cavity is entered
Figure 15-6. A template of the frontal sinus is made from an
anteroposterior radiograph taken from 6 ft away (Caldwell’s view).
The template is used as an overlay to guide the surgeon in designing
the osteotomy.
A
B
Figure 15-7. A, Either a bicoronal fl ap or a brow incision may be
used to expose the anterior frontal bone. B, Bicoronal fl ap used to
remove a mucocele of the frontal sinus.
(Fig. 15-9). The osteotomies may also be completed
with a high-speed drill, but this usually results in greater
bone loss at the edges of the osteotomies. The intersi-
nus septum must be fractured with an osteotome or
elevator after the bone fl ap has been fully separated
from the orbital rim on either side. The bone fl ap is
gently pried away from the skull, and the base of the
fl ap is fractured. Specimens are obtained for culture
and sensitivity testing, and the mucosa is removed from
all the recesses of the frontal sinus. Magnifi cation via
the operating microscope, loupes, or endoscope is

Chapter 15
External Approaches to the Frontal Sinus
117
is used to completely obliterate the nasofrontal duct.
The sinus may then be obliterated with an adipose
tissue graft from the abdomen.
The bone fl ap (from which the mucosa has been
removed) is returned to its anatomic site. Fixation of
the fl ap is then undertaken with either fi ne wire or silk
or with adaptation plates. The incision is closed in layers
with a suction drain left in place. The eyelid sutures are
removed, and a compression dressing is applied.
Postoperative Management
A compressive dressing is maintained for 48 to 72 hours
postoperatively. Administration of antibiotics for longer
than 24 hours is unnecessary unless acute infection was
encountered during surgery. The drain is removed 24
to 48 hours after surgery. Some degree of periorbital
edema and ecchymosis develops in virtually all patients.
Maintaining a head-elevated position may be helpful in
reducing periorbital edema. Patients may be discharged
after drain removal. A proportion of patients continue
to report headache, frontal fullness, and pain after
frontal sinus obliteration. The diagnosis of recurrent
frontal sinus disease after osteoplastic fat obliteration
continues to be a diffi cult clinical problem.17 Modern
imaging techniques may serve to help identify these
problem cases for further treatment,18 and some of
them may be salvageable by endoscopic techniques.19
Lynch’s Frontoethmoidectomy
The Lynch frontoethmoidectomy establishes communi-
cation between the fl oor of the frontal sinus and the
anterior ethmoid cells, in effect marsupializing the
most anterior of the paranasal sinuses with the middle
meatus (Fig. 15-10).20 Its effi cacy is based on re-estab-
lishment of the integrity of drainage of the frontal sinus
into the middle meatus. Despite many adjunctive tech-
niques developed to maintain patency of the nasofron-
tal duct, the Lynch procedure is associated with an
unacceptably high degree of recurrence of frontal
obstruction, mucocele formation, and sinusitis. It may
be used in patients who are not candidates for an endo-
scopic Draf or Lothrop procedure because of anatomic
limitations.
The procedure is done with the patient under
general anesthesia. A temporary tarsorrhaphy is per-
formed, and an incision is made above the medial
aspect of the upper eyelid, curved, and then carried
inferiorly down to the level of the medial canthus. The
periosteum is elevated posteriorly, and a cutting burr is
used to trephine the frontal sinus. A Kerrison- or Citelli-
type rongeur is used to provide communication between
the fl oor of the frontal sinus and the anterior ethmoid
air cells, which are removed until free communication
with the middle meatus is obtained. Diseased mucosa is
removed from the frontal recess as completely as possi-
ble. An attempt must be made to reconstruct the naso-
frontal duct with a nasoseptal mucosal fl ap. This is
unnecessary when treating patients for fractures of the
anterior wall of the frontal sinus or during removal of
osteoma because the duct should not be traumatized
Figure 15-8. After the template has been used to demonstrate the
extent of the frontal sinus, the pericranium is elevated and refl ected
inferiorly. In this way the pericranium can be used to reinforce the
closure at the completion of the procedure.
Figure 15-9. The osteoplastic fl ap is outlined with an oscillating
saw. The osteotomy is beveled (inset) to ensure that the fl ap will fi t
securely when it is replaced at the completion of the procedure.
helpful to ensure that all the mucosa has been removed.
This is important in preventing mucocele formation.
The intersinus septum is removed with a rongeur, and
other septa are taken down to bone with a curette or
burr. A muscle plug taken from the temporalis muscle

118
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
Figure 15-10. A and B, The Lynch frontoethmoidectomy estab-
lishes communication between the frontal sinus and the middle
meatus. Success is predicated on the ability to establish a mucosal
lined nasofrontal recess.
and one would hope that it will return to its premorbid
condition.
Postoperative Management
At the completion of the procedure, the eyelid sutures
are removed and the cornea is irrigated with balanced
saline solution. An ophthalmic ointment is applied to
the incision. The patient should be maintained in a
head-elevated position during this time to further
reduce postoperative edema.
Once discharged from the hospital, the patient is
seen as an outpatient for intranasal examination and
débridement of crusts. After the fi rst postoperative visit
(7 to 10 days postoperatively), a program of intranasal
irrigation with normal saline solution is instituted.
Ablation of the Frontal Sinus
When an acute or chronic pyocele of the frontal sinus
results in osteomyelitis of the anterior wall of the frontal
sinus, effective surgical therapy may require débride-
ment of infected bone. This condition may be mani-
fested as a subperiosteal abscess of the forehead (Pott’s
puffy tumor, Fig. 15-11). The frontal sinus may be
ablated by complete removal of the anterior wall of the
frontal sinus, with or without the supraorbital rims, by
using a cutting burr to remove the bony protuberances.
The sinus is prepared as for a fat obliteration proce-
dure, except that the skin of the forehead is laid down
smoothly on the healthy posterior table of the sinus.
Exposure of the sinus is through a bicoronal incision as
described previously. A suction drain is inserted, and a
bulky compressive dressing is applied.
Reconstruction of the cosmetic defect should be
postponed until it is ensured that the infectious process
has been completely eradicated. In most circumstances,
surgeons would wait 3 to 12 months before undertaking
reconstruction.
Figure 15-11. Pott’s puffy tumor in a 27-year-old. Note the evi-
dence of a mass in the forehead.
Postoperative Management
Postoperative management of patients proceeds as for
frontal sinus obliteration. Patients may be discharged
from the hospital when the drain is removed if the
healing is proceeding without complication and no evi-
dence of infection is demonstrated by either erythema
or a subcutaneous collection. The patient is instructed
to keep the wound clean. It should be maintained dry
until the fi fth postoperative day, when the patient may
shower or wash and gently pat the incision dry. Facial
sutures are removed on the fi fth postoperative day,
whereas scalp sutures are ordinarily maintained for 10
to 14 days postoperatively.
COMPLICATIONS
Postoperative wound infection is unusual after surgery
on the frontal sinus. At the time of surgery all purulent
material and diseased mucosa are removed, osteomy-
elitic bone is resected, and the wound is irrigated to
remove bone and infected debris and closed with drain-
age appropriate to evacuate serum and clot. Routine
administration of perioperative antibiotics probably
contributes to the low incidence of postoperative infec-
tion in these patients.
When a postoperative collection of blood or serum
is identifi ed, appropriate treatment consists of aspira-
tion, a pressure dressing, and the administration of
antibiotics.
If a cerebrospinal fl uid leak is diagnosed, re-explo-
ration may be necessary. The procedure may require
either removal of the posterior wall of the frontal sinus
to allow adequate exposure for repair of the dural tear
or anterior fossa craniotomy. In either case, the dural
tear must be repaired primarily or with a fascial graft,
after which it must be isolated from the sinonasal tract.
Ordinarily, this is undertaken through obliteration of
the frontal sinus with adipose tissue.
In patients who have undergone an osteoplastic
fl ap procedure, postoperative osteomyelitis of the ante-
rior bone fl ap is encountered occasionally. This may
refl ect preoperative existence of a severe infection with

Chapter 15
External Approaches to the Frontal Sinus
119
extension to bone. This complication is best prevented
by débridement of infected bone and maintenance of
periosteal vascular supply to the anterior bone fl ap.
Should osteomyelitis occur, administration of intrave-
nous antibiotics is appropriate; however, this may be
insuffi cient to control the problem, and wound explo-
ration with débridement of the anterior bone fl ap may
be required. Maintenance of the fat graft may improve
the postoperative cosmetic result, but many patients will
require subsequent cranioplasty when the infectious
complication has resolved.21
A patient undergoing elective surgery of the frontal
sinus should be counseled that inadvertent entry into
the anterior fossa is a well-described, though rare com-
plication. When encountered, it is critical that the
potential for dural injury be immediately evaluated and,
when necessary, the dura repaired. In these circum-
stances, postoperative complications may be reduced or
eliminated. Injury to the dural venous sinuses is more
unusual but of greater potential signifi cance. Similarly,
this sort of complication can be minimized by immedi-
ate recognition and repair.
The last 10 years have seen an increase in all
endoscopic procedures, and readers are directed to
Chapter 16. The indications for any of the external
procedures discussed in this chapter are progressively
decreasing.22-24
References
1. Ritter RN, Fritsch MH (eds): Atlas of Paranasal Sinus Surgery.
New York, Igaku-Shoin, 1991.
2. Schaeffer JP: The Embryology, Development and Anatomy of the
Nose, Paranasal Sinuses, Nasolacrimal Passageways and Olfactory
Organs in Man. Philadelphia, Blakiston, 1920.
3. Rice DH, Schaefer SD (eds): Endoscopic Paranasal Sinus Surgery,
3rd ed. New York, Raven, 2003.
4. Duvoisin B, Schnyder B: Do abnormalities of the frontonasal duct
cause frontal sinusitis? A CT study of 198 patients. AJR Am J
Roentgenol 159:1295-1298, 1992.
5. Reddy KT, Gilhooly M, Wallace M, Ali MH: Frontal sinus carci-
noma presenting as acute sinusitis. J Laryngol Otol 105:121-122,
1991.
6. Ruoppi P, Sepp J, Nuutinen J: Acute frontal sinusitis: Etiological
factors and treatment outcome. Acta Otolaryngol 113:201-205,
1993.
7. Wigand ME: Operations on the frontal sinus. In Wigand ME (ed):
Endoscopic Surgery of the Paranasal Sinuses and Anterior Skull
Base. New York, Thieme, 1990, pp 120-133.
8. Coyne TJ, Kemp RJ: Intracranial epidural abscess: A report of
three cases. Aust N Z J Surg 63:154-157, 1993.
9. Milo R, Schiffer J, Karpuch J, et al: Frontal bone osteomyelitis
complicating frontal sinusitis caused by Haemophilus infl uenzae
type a. Rhinology 29:151-153, 1991.
10. Holder J, Corbin D, Marquez S, et al: Pott’s puffy tumour and
subdural empyema following frontal sinusitis. West Indian Med J
40:33-36, 1991.
11. Pender ES: Pott’s puffy tumor: A complication of frontal sinusitis.
Pediatr Emerg Care 6:280-284, 1990.
12. Gerber ME, Myer CM, Prenger EC: Transcutaneous frontal sinus
trephination with endoscopic visualization of the nasofrontal
communication. Am J Otolaryngol 14:55-59, 1993.
13. Goodale R, Montgomery W: Experiences with the osteoplastic
anterior wall approach to the frontal sinus. Arch Otolaryngol
50:271-283, 1958.
14. Hardy JM, Montgomery WM: Osteoplastic frontal sinusitis: An
analysis of 250 operations. Ann Otol Rhinol Laryngol 85:523-532,
1976.
15. Alford BR, Gorman GN, Mersol VF: Osteoplastic surgery of the
frontal sinus. Laryngoscope 75:1139-1149, 1965.
16. Calcaterra TC, Strahan RW: Osteoplastic fl ap technique for
disease of the frontal sinus. Surg Gynecol Obstet 12:505-510,
1971.
17. Catalano PJ, Lawson W, Som P, Biller HF: Radiographic
evaluation and diagnosis of the failed frontal osteoplastic fl ap
with fat obliteration. Otolaryngol Head Neck Surg 104:225-234,
1991.
18. Anand VK, Hiltzik DH, Kacker A, Honrado C: Osteoplastic fl ap
for frontal sinus obliteration in the era of image-guided endo-
scopic sinus surgery. Am J Rhinol 19:406-410, 2005.
19. Nair S, Ananda A, Wormald PJ: Endoscopic Lothrop procedure
for failed frontal sinus obliterations. Laryngoscope 113:276-283,
2003.
20. Lynch RC: The technique of a radical frontal sinus opera -
tion which has given me the best results. Laryngoscope 31:1-5,
1921.
21. Olson NR, Newman MH: Acrylic frontal cranioplasty. Arch Oto-
laryngol 89:744-777, 1969.
22. Davis WE: Growing obsolescence of the frontal sinus obliteration
procedure. Arch Otolaryngol 131:532-533, 2005.
23. Lanza DC: Frontal sinus obliteration is rarely indicated. Arch
Otolaryngol 131:531-532, 2005.
24. Sillers MJ: Frontal sinus obliteration: An operation for the
archives or modern armamentarium. Arch Otolaryngol 131:529-
531, 2005.
PEARLS
• Success of external frontal sinus obliteration relies
on meticulous technique with magnifi cation.
• Image guidance–assisted templates are an
alternative to the 6-ft Caldwell view.
• Tissue should be taken at surgery for culture to aid
in postoperative therapy.
• A midforehead crease approach is aesthetically
satisfactory in patients with a receding hairline.
PITFALLS
• Obliterative procedures do not allow assessment of
symptoms with postoperative imaging studies.
• Persistent wound problems are unusual, and
infected bone or a foreign body should be
considered.
• Failure of obliterative frontal sinus surgery is
infrequently salvageable with an endoscopic
approach.
• Extensive dissection or cautery near the supraorbital
neurovascular bundle will cause long-standing
complaints of numbness.

Chapter 16
Endoscopic Approach to the Frontal Sinus
Barry M. Schaitkin
Endoscopic surgery on the frontal sinus is, for the most
part, predicated on understanding the anatomy of the
frontal recess. Frontal sinus drainage is infl uenced and
affected by the adjacent cellular structures, much as the
maxillary sinus is dependent on the confi guration that
the patient’s uncinate process, ethmoid bulla, and
Haller cells exert on the outfl ow tract.
Most commonly, the uncinate process ascends from
its inferior attachment to the inferior turbinate and
from its anterior attachment to the lacrimal bone and
blends in with the medial wall of the agger nasi cell (Fig.
16-1). In these cases the frontal sinus will drain between
the uncinate process and the middle turbinate as it does
85% of the time.1,2 In the remaining cases, the uncinate
attaches to the middle turbinate or the skull base, and
the frontal sinus drains directly into the infundibulum.
If the uncinate attaches both medially to the middle
turbinate and laterally to the agger nasi, the frontal
sinus will be seen to drain posteriorly.
PATIENT SELECTION
The vast majority of patients who have frontal sinus
disease refractory to medical therapy can have their
frontal sinus surgery managed endoscopically. However,
for certain conditions, including some benign and
malignant tumors, pathology situated laterally within
the sinus, and very small sinuses, an open approach
remains a very good and reliable surgical option (see
Chapter 15).
Acute frontal sinusitis is not usually a good indica-
tion for endoscopic frontal sinus surgery. These patients
have intense hyperemia and infl ammation, and the like-
lihood of creating symptomatic scarring in the frontal
recess is great. I prefer to manage these patients as true
medical emergencies with intravenous antibiotics and
classic frontal sinus trephination. Surgery on the frontal
recess, if necessary, should be delayed until the acute
process has resolved.
The surgeon will generally fi nd that complications
of sinus infections involving either the central nervous
system or the orbit are most commonly associated with
acute and not chronic sinus problems. The frontal sinus
is a dangerous sinus in this regard, and meningitis and
periorbital and brain abscesses are possible severe
complications.
Those in whom chronic frontal sinus problems
develop are considered surgical candidates according to
the same criteria as for other endoscopic sinus surgery.
Patients should have the criteria for sinusitis proposed
by the American Academy of Otolaryngology–Head and
Neck Surgery, and they should have failed medical
therapy consisting of at least a minimum 3 weeks of anti-
biotic therapy. Imaging obtained at the end of treatment
is used to determine the extent of surgery.3
PREOPERATIVE PLANNING
All patients who are to undergo frontal sinus surgery
should have computed tomography (CT) scans taken
in both the axial and coronal plane. If available and
deemed necessary, computerized navigation provides
the additional sagittal projection. Radiographs should
be reviewed carefully before surgery to evaluate the
uncinate process, agger nasi cells, and the size and
depth of the frontal sinus. Scans should be reviewed to
note the position of the anterior ethmoid artery and
the presence or absence of supraorbital ethmoid cells.
Patients should be suspected of having supraorbital
ethmoid cells if multiple septations are seen within the
frontal sinus on coronal images.
Antibiotics and possibly topical and systemic ste-
roids should be used to minimize vascularity and edema
in the frontal recess, which could make surgery more
121

122
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
dangerous because of bleeding with resultant decreased
visibility.
Patients who will undergo an advanced endoscopic
drill-out procedure must have a large enough sinus to
begin with. A sinus with less than 9-mm anterior poste-
rior space is diffi cult to keep open in the postoperative
period.4
Patients with erosion between the frontal sinus and
the orbit and those with erosion of the posterior wall of
the frontal sinus are more easily treated by an endo-
scopic drill-out procedure than by an open frontal sinus
obliteration operation. This avoids the diffi cult surgical
conundrum of attempting to eradicate all mucosal rem-
nants off the dura or periorbita.
The procedure begins in the holding area with the
use of topical decongestants applied 30 minutes before
the procedure; repeat topical therapy is given at 15
minutes and on call in the operating room. The patient
arrives in the operating room for either general or
monitored anesthesia, depending on patient prefer-
ence and the planned extent of surgery.
Surgical preference will dictate the way that the
operating room and the Mayo stand are organized. We
use a two-handed technique,5 which is particularly
helpful in patients with acute infl ammation and bleed-
ing. Many different systems of powered instruments are
available, and optimal settings will vary. In general, if
one is having diffi culty, the device should be slowed
down to allow a greater period when the window is
open to entrap the tissue, particularly during surgical
removal of polyps with these devices.
There are many ways to clean the lens of the scope
and prevent fogging: some scopes are self-irrigating,
some soft tissue shavers irrigate the lens clear, and in the
two-surgeon technique the assistant instills water into
the nose with a 60-mL syringe by way of a blunt 18-gauge
needle. Defogging agent may be purchased from mul-
tiple manufacturers as well. It is helpful but should not
be used if an irrigating sleeve is on the scope because
the fi lm prevents irrigation of the tip of the scope. A
clean scope and a dry fi eld will enable the procedure
to progress satisfactorily and decrease frustration and
complications.
To maintain a dry fi eld, oxymetazoline and 1:1000
topical adrenaline are applied on 1/2- by 3-inch radi-
opaque neuropatties. Both are poured by the circulator
into labeled basins. The adrenaline is dyed with a single
drop of methylene blue to further decrease the risk of
confusing it with local anesthetic and injecting it into
the nasal mucosa.
All procedures are done with the injection of a local
anesthetic, 1% lidocaine (Xylocaine), and a vasocon-
strictor, 1:100,000 epinephrine. The injections sites are
at the superior attachment of the middle turbinate and
the inferior aspect of the uncinate process, as well as at
the tail of the middle turbinate. After 5 minutes have
passed, the procedure is begun.
SURGICAL TECHNIQUE
The frontal sinus, like all sinuses, should be treated
operatively only if all medical therapy has failed and the
sinus is symptomatic. Because the frontal sinus is
involved radiographically in just 20% or less of patients,
it should be addressed only when absolutely necessary,
particularly in the case of the frontal sinus (as opposed
to the other paranasal sinuses) since rescuing an
iatrogenically impaired sinus can be diffi cult.
Therefore, when patients lack signifi cant frontal
sinus pathology on CT and are asymptomatic, the unci-
nate process will be taken up as far as the agger nasi
cell. A synechia that might form between an intact
middle turbinate and the agger region will not usually
block the frontal sinus.
In patients with frontal sinus symptoms and pathol-
ogy, the frontal sinus can be explored if surgically indi-
cated. This entails either frontal sinus trephination to
irrigate the frontal sinus or dissection of the agger nasi
cell or cells to improve the outfl ow tract of the frontal
sinus.
Frontal Sinus Trephination
Frontal sinus trephination can be used for treatment of
a chronically infl amed frontal sinus. This technique is
used as an adjunct to endoscopic sinus surgery and is
not the same technique that is generally used for drain-
ing an acute frontal sinus (Fig. 16-2). The frontal sinus
is entered after reviewing the CT scan, with especial
notation of the depth of the sinus on an axial scan or
on a navigation system. All the trephination sites should
be measured for maximum safe penetration, particu-
larly in females, who have smaller sinuses than males
do. Commercially available trephination kits are not
designed to be used to the maximum depth of penetra-
tion in all patients.
If not using a navigation system, the supraorbital
foramina can be used as a good surgical landmark (Fig.
16-3A). A line connecting the two palpated foramina
generally represents a safe zone in a well-pneumatized
frontal bone as shown with image guidance (see Fig.
16-3B). A small stab incision, large enough to admit a
soft tissue protector, is made in the most medial aspect
of the eyebrow. The eyebrow is then raised up onto the
fl at surface of the frontal bone on a line above and away
from the neurovascular bundle. Water is placed in the
protector sleeve and slow forward rotation is used to
penetrate the front wall of the frontal sinus only. A
trocar, preferably fl uted to lock into the bone, is inserted
to manage increased intrasinus pressure.
Figure 16-1. Line diagram of the uncinate attachment. (From
Stammberger H, Hawke M: Essentials of Functional Sinus Surgery, Mosby,
1993.)
2
3
4
1
5
cl
cm

Chapter 16
Endoscopic Approach to the Frontal Sinus
123
The surgeon views the nasofrontal recess endoscop-
ically and irrigates the sinus personally to assess the
amount of pressure required. Over time one develops
a feel for whether the sinus is truly open. The proce-
dure can be ended if the sinus is clearly irrigated at low
pressure. This allows treatment of the sinus completely
without trauma to the frontal recess.
If the sinus does not open with irrigation, the water
can be used to help the surgeon proceed to dissection
of the frontal recess. The frontal sinus drainage site is
clearly identifi ed by the fl ow of water.
Basic Endoscopic Surgery on the
Frontal Recess
Dissection of the frontal recess requires frontal sinus
instruments and a precise understanding of the anatomy
of this region, particularly in the current patient.
Readers should review the classifi cation of agger nasi
cells by Kuhn and Bolger.6
Because the frontal sinus most frequently drains
between the middle turbinate and the agger nasi–
uncinate complex, a frontal sinus with a single agger
nasi cell (Kuhn-Bolger type 1) is opened by removing
the medial wall of the agger nasi cell. Ideally, this is
performed with meticulous and atraumatic technique.
If submucosal resection of the bone of the medial wall
of the agger is performed, a microdébrider can trim the
remaining mucosal sleeve to the desired level. This
avoids the dangerous practice of grasping and tearing
mucosa in the nasofrontal recess. Once again, the mini-
trephine can confi rm that surgery has been completed
and guide the surgeon in cases in which the site of
frontal sinus drainage is confusing.
Advanced Surgery on the Frontal Recess
Surgeons should have multiple procedures in their
armamentarium for coping endoscopically with a trou-
blesome frontal sinus. This allows more extensive
surgery without external incisions to approach neo-
plasms, mucoceles, fungal processes, and iatrogenic
stenoses.
The most common problem is a lateralized middle
turbinate stump when the previous surgeon has removed
the lower middle turbinate. This is very effectively dealt
with in a minimally invasive manner by the frontal sinus
rescue procedure described by Kuhn (Fig. 16-4).7,8 In
this procedure the scar is lysed to create three layers of
the middle turbinate: mucosa on the medial and lateral
surface and the bone of the middle turbinate in the
middle. The medial mucosa and bone are removed and
the lateral mucosa is used as a fl ap and draped toward
the septum.
The next level of intervention involves more exten-
sive bone removal in the frontal recess. Wormald has
introduced the axillary fl ap procedure whereby a fl ap
is raised above the attachment site of the middle turbi-
nate, which is rotated out and replaced.9 Kerrison
forceps allow more direct access to the frontal recess
Figure 16-2. Trephination is performed through an incision made
in the medial aspect of the brow. The fl oor of the frontal sinus is
exposed and a drill is used to drain the sinus. The lateral wall of the
nasal frontal recess is then removed down to provide communication
between the frontal sinus and middle meatus.
Figure 16-3. Line diagram of a supraorbital foramina line of safe
entry (A) and use of image guidance to confi rm the entry point
(B).
A
B

124
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
without resorting to angled telescopes. Caution must be
used when removing infl amed bone in this area because
obliterating scar tissue can form in this setting.
Frontal sinus drill-out procedures are the most
radical of endoscopic procedures for infl ammatory
disease. The procedure (which has been called a drill-
out procedure, Draf procedure, modifi ed Lothrop pro-
cedure, and other names) involves removing a variable
amount of the fl oor of the frontal sinus. The fl oor can
be removed from the orbit to the middle turbinate,
from the orbit to the septum, and from orbit to orbit
with removal of the upper nasal septum.
For all drill-out procedures we always use a naviga-
tion system. These systems, when properly calibrated,
allow more precise documentation of the anatomic
1
2 3 4
Figure 16-4. Line diagram of three layers of Kuhn frontal sinus
rescue. (From Kuhn FA, Javer A, Nagpal K, Citardi M: The frontal sinus
rescue procedure: Early experience and 3 year follow-up. Am J Rhinol 14:211-
216, 2000.)
Figure 16-5. Creating the septal window. (May M, Schaitkin B:
Frontal sinus surgery: Endonasal drainage instead of an external osteoplastic
approach. Op Tech Otolaryngol Head Neck Surg 31:184-192, 1995.)
Figure 16-6. Midline appearance of the frontal sinus fl oor after
removal of the septal window (the white arrow is the superior cut edge
of the nasal septum, the red arrow is the left middle turbinate, and the
blue star is the confl uence of the nasal bone and the frontal bone,
which forms the frontal sinus fl oor). (May M, Schaitkin B: Frontal sinus
surgery: Endonasal drainage instead of an external osteoplastic approach. Op
Tech Otolaryngol Head Neck Surg 31:184-192, 1995.)
Figure 16-7. Thirty-degree endoscopic appearance of the frontal
fl oor in the midline with both middle turbinates in place.
landmarks before beginning to use the drill. The surgi-
cal description here is for an orbit-to-orbit exposure,
which the reader can modify if unilateral exposure is
desired.
The procedure begins with removal of a quarter-
sized area of the nasal septum anterior to the middle
turbinates (Fig. 16-5). Exposure allows visualization of
the confl uence of the nasal and frontal bones (the keel)
and both middle turbinates (Figs. 16-6 and 16-7). The
frontal sinus is most easily approached with a curved
high-speed drill with suction. Irrigation can be added
by an assistant. In a unilateral approach, the bone above
the middle turbinate attachment side is gradually taken
down while avoiding perforation of the nasal bone.
Once entered (Fig. 16-8), the sinus can be enlarged

Chapter 16
Endoscopic Approach to the Frontal Sinus
125
Figure 16-8. Computerized navi-
gation showing perforation of the
midline and entry into the frontal
sinus.
Figure 16-9. Endoscopic appearance (bottom right) of cadaver dis-
section of a completed drill-out procedure with navigation
guidance.
toward the septum, and this opening is communicated
to the nasofrontal recess. For bilateral procedures the
sinus can most safely be entered in the midline through
the frontal sinus fl oor, which is progressively enlarged
laterally (Fig. 16-9). As with the unilateral procedure,
the procedure ends when the drilled-out sinus fl oor
communicates with the natural ostium. The inner sinus
septum should be taken down as high as possible with
preservation of mucosa in this area. It is vitally impor-
tant to preserve the mucosa on the posterior aspect of
the sinus to achieve a favorable healing result. Some
wound contraction occurs over time but is tolerated if
the opening remains generous, as Figure 16-10 shows
in a 5-year postoperative endoscopic view (see also
Video 16-1).
POSTOPERATIVE CARE
Basic frontal sinus procedures are treated as all endo-
scopic sinus procedures, with saline irrigation and
minimal
postoperative
débridement.
Packing
is
avoided in all patients, and less than 25% of patients
receive some type of self-absorbing hyaluronic acid
dressing.
Drill-out procedures are treated similarly without
packing or stents. Antibiotics and systemic and topical
steroids are used in all drill-out proceduresd until the
bone has remucosalized. Patients in whom a drill has
been used will have more mucosal loss than the majority
of endoscopic sinus surgery patients and may require
more débridement than usual. The surgeon should see
these patients at 1, 3, and 6 weeks postoperatively to
perform gentle débridement and determine the extent
of antibiotic and steroid treatment needed. This is
highly individualized and based on the patient’s
original pathology and the healing result seen
endoscopically.
COMPLICATIONS
Unintended entry into the central nervous system and
orbit is the main serious risk associated with all frontal
sinus procures and is exceedingly rare. Epistaxis and
orbital ecchymosis are the most common complica-
tions, but they occur in less than 1% of patients. Syn-
echiae formation continues to be a signifi cant problem
in this area and is best avoided by meticulous technique
with minimal removal of mucous membrane. Results by
numerous authors put the success rate of this proce-
dure in avoiding an osteoplastic fl ap at 80% to
90%.10-12
CONCLUSION
Frontal sinus surgery requires precision in diagnosis
and surgical technique. Detailed review of the patient’s
endoscopic and imaging fi ndings preoperatively with
consideration of the uncinate process, agger nasi region,
and size and confi guration of the frontal sinus allows
individually tailored approaches. Iatrogenic frontal
sinus occlusion is diffi cult to rescue and should be
avoided if possible.

126
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
References
1. Wake M, Takeno S, Hawke M: The uncinate process: A histologi-
cal and morphological study. Laryngoscope 104:364-369, 1991.
2. Wormald PJ: The agger nasi cell: The key to understanding the
anatomy of the frontal recess. Otolaryngol Head Neck Surg
129:497-507, 2003.
3. Anon JB, Jacobs MR, Poole MD, et al: Antimicrobial treatment
guidelines for acute bacterial rhinosinusitis (Sinus and Allergy
Partnership). Otolaryngol Head Neck Surg 123:5-31, 2000.
4. Farhat FT, Figueroa RE, Kountakis SE: Anatomic measurements
for the endoscopic modifi ed Lothrop procedure. Am J Rhinol
19:293-296, 2005.
5. May M, Hoffman DF, Sobol SM: Video endoscopic sinus surgery:
A two-handed technique. Laryngoscope 100:430-432, 1990.
6. Kuhn FA, Bolger WE, Tisdal RG:. The agger nasi cell in frontal
recess obstruction: An anatomic, radiologic, and clinical correla-
tion. Op Tech Otolaryngol Head Neck Surg 2:226-231, 1991.
7. Citardi MJ, Javer AR, Kuhn FA: Revision endoscopic frontal sinus-
otomy with mucoperiosteal fl ap advancement: The frontal sinus
rescue procedure. Otolaryngol Clin North Am 34:123-132,
2001.
8. Kuhn FA, Javer A, Nagpal K, Citardi M: The frontal sinus rescue
procedure: Early experience and 3 year follow-up. Am J Rhinol
14:211-216, 2000.
9. Wormald PJ: The axillary fl ap approach to the frontal recess.
Laryngoscope 1:494-499, 2002.
10. Kountakis SE, Gross CW: Long-term results of the Lothrop opera-
tion. Curr Opin Otolaryngol Head Neck Surg 11:37-40, 2003.
11. Stankiewicz JA, Wachter B: The endoscopic modifi ed Lothrop
procedure for salvage of chronic frontal sinusitis after osteoplas-
tic fl ap failure. Otolaryngol Head Neck Surg 129:678-683, 2003.
12. May M, Schaitkin B: Frontal sinus surgery: Endonasal drainage
instead of an external osteoplastic approach. Op Tech Otolaryn-
gol Head Neck Surg 3:184-192, 1995.
PEARLS
• Excellent understanding of the anatomy of the
frontal recess is imperative.
• Frequent cadaver dissections are necessary for
performing advanced frontal sinus surgery.
• Computerized navigation is essential for advanced
frontal sinus surgery.
• Frontal sinus trephination can improve
understanding of the frontal recess by showing
where the frontal sinus drains and decreasing the
extent of surgery and trauma.
• Only patients who are candidates for an
osteoplastic fl ap procedure are candidates for a
frontal sinus drill-out procedure.
• The surgeon should become profi cient in all other
paranasal sinus surgery before attempting the
frontal sinus, which tends to be less forgiving.
• Frequent review of CT scan anatomy in this area,
including three-dimensional reconstructions, is
strongly encouraged.
• Dedicated frontal sinus instruments, including
curved microdébrider tips and drills, allow minimal
approaches designed to minimize trauma to the
frontal recess.
PITFALLS
• Extensive use of powered instruments in the frontal
sinus can cause stenosis.
• Operating in the face of acute infection decreases
visualization and increases the risk for scar
formation.
• Drilling too far anteriorly in a frontal sinus drill-out
procedure will cause fenestration of the nasal bones
(Fig. 16-10).
• Leaving the frontal sinus septum in place increases
the risk for stenosis.
• Bare bone should be covered as much as possible to
improve healing.
• The posterior mucosal covering of the newly created
ostium of a frontal drill-out procedure should not
be disturbed.
Figure 16-10. Endoscopic appearance of a healed drill-out proce-
dure after some wound contraction.

Chapter 17
Antrochoanal Polyp
Barry M. Schaitkin
An antrochoanal polyp was fi rst described by Killian in
1906.1 The polyp usually originates within the maxillary
sinus and is characterized by the symptom of unilateral
nasal obstruction. It is more common in the pediatric
age group and represents the most common nasal and
sinus tumor in children. In the general population it is
said to account for 4% to 6% of all nasal polyps.2 In a
recent study of 24 patients the mean age was 23 years
(range, 11 to 40).1
The etiology of antrochoanal polyps remains con-
troversial, and both allergic and infectious causes have
been promulgated.1,3 Though classically thought to not
have an allergic component, two series have found a
signifi cant atopic predisposition in their patients with
antrochoanal polyps.1,4 Medical treatment, such as anti-
biotics, decongestants, and systemic and topical ste-
roids, has not proved to be curative. Recurrence of
symptoms after cessation of such medical therapy is
common, as is recurrence after inadequate surgical
procedures such as nasal polypectomy. Because of the
high incidence of recurrence after simple polypectomy,
a more complete surgical procedure must be
performed.
Schramm and Effron5 studied 32 children ranging
in age from 7 to 16 years who underwent a Caldwell-Luc
operation as a primary or secondary procedure for the
removal of antrochoanal polyps. Only one of these chil-
dren required a reoperation for recurrence. The opera-
tive complication rate of 3% for all surgical procedures
performed is equal to that reported in the adult litera-
ture for the Caldwell-Luc operation.
All current series advocate an endoscopic approach
to this lesion, which is our preference.4,6,7
PATIENT SELECTION
Patients with an antrochoanal polyp generally have uni-
lateral nasal obstruction. There may be a report of asso-
ciated thick mucopurulent exudate. In the pediatric
population, sleep disturbance and mouth breathing are
common. In adults, the symptoms of nasal obstruction
may be accompanied by snoring and headache. Patients
will usually have received multiple courses of antibiotics
before being evaluated by an otolaryngologist.
Physical examination reveals a gray-white or some-
times hyperemic polypoid mass generally fi lling the nose
and nasopharynx. Occasionally, the mass may be seen in
the nasopharynx simply on examination of the oral
cavity when the palate is elevated. Thick mucopurulent
exudate may be found in the nasal cavity on anterior
rhinoscopy. Patients with unilateral nasal obstruction
who are old enough to tolerate offi ce-based nasal endos-
copy must undergo it in the fully decongested state. In
this case, barring a severe septal deviation, the antrocho-
anal polyp will be easily visualized between the middle
turbinate and the lateral nasal wall (Fig. 17-1). The polyp
may be seen extending posteriorly into the nasopharynx
if it has reached suffi cient size. Classically, the polyp does
not exit via the natural ostium; instead, in our series it
has always exited the maxillary sinus via an accessory
ostium. The implication of this fi nding in the cause of
the condition is unexplained.
PREOPERATIVE PLANNING
Imaging with computed tomography (CT) is important
in confi rming the clinical impression of an antrocho-
127

128
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
4-mm soft tissue shaver and a 30-degree telescope can
be introduced with a minimally invasive technique. In
some cases a double-barrel canine fossa puncture is
performed to allow both the shaver and scope to be
introduced—the scope through the trocar sleeve and
the shaver directly through the front face of the maxilla.
For the shaver, a standard canine fossa puncture is
performed above the gingivobuccal sulcus superior to
the canine tooth in the palpated fossa. An extended
fi nger on the cheek prevents perforation of the poste-
rior wall of the maxillary sinus after breeching the ante-
rior wall. The nondominant hand may be kept on the
orbital rim to prevent the trocar complex from sliding
too superiorly on the front face of a dense maxilla and
damaging the orbit.
Once the trocar and sleeve are within the sinus, the
trocar can be removed and a telescope placed for full
exposure. Best results with the shaver occur with removal
of both the sleeve and trocar and placement of the
device through the surgical tract created. A 30-degree
scope is ideal for complete inspection of the maxillary
sinus. No packing or dressings are needed, and addi-
tional surgery on the ethmoid sinus is almost never
required.
External Approach
An antrochoanal polyp can also be removed via a
Caldwell-Luc operation (see Chapter 8). In this proce-
dure the sinus mucosa is removed en bloc to achieve a
margin around the segment with the stalk of the
polyp.
After the antral mucosa is mobilized, the soft palate
is retracted and the polyp in the nasopharynx is grasped
with a clamp. While the polyp is gently pulled into the
oral cavity, the mucosa surrounding the natural ostium
is dissected free under direct vision, and the polyp
along with the resected portion of the antral mucosa is
removed as one unit (Fig. 17-3).
POSTOPERATIVE CARE
For the endoscopic approach, nasal saline irrigation
usually serves as adequate postoperative care. Wide
Figure 17-1. Endoscopic view of the left nasal vault demonstrating
an antrochoanal polyp (arrow) exiting into the nose via an accessory
ostium behind an intact uncinate process (cross).
anal polyp. Radiographic evaluation reveals unilateral
opacifi cation of the maxillary antrum and rarely associ-
ated opacifi cation of the ethmoid sinuses. CT scanning
will reveal the mass associated with opacifi cation of the
maxillary sinus on the involved side (Fig. 17-2).
SURGICAL TECHNIQUE
Endoscopic Approach
Antrochoanal polyps must be completely excised to
avoid recurrence. Endoscopically, this can sometimes
be performed exclusively endonasally; however, even
with 30- and 70-degree telescopes it is often necessary
to also approach the maxillary sinus component via a
canine fossa puncture.
The nasal component can easily be removed endo-
scopically. A maximal maxillary antrostomy allows full
view of the sinus component and usually the stalk,
which has a variable location within the sinus. If the
stalk is not readily accessible through the transnasal
route, a canine fossa puncture is performed. A standard
A
B
Figure 17-2. Computed tomog-
raphy scan demonstrating an
antrochoanal polyp from a left
opaque antrum into the nose on a
coronal image (A) and extending
into the nasopharynx on an axial
image (B) (arrow).

Chapter 17
Antrochoanal Polyp
129
postoperative evaluation of the surgical site is afforded
by the maxillary antrostomy. Thirty-degree tele-
scopes and even fl exible laryngoscopes allow wide
surveillance.
COMPLICATIONS
The pitfall in surgery for antrochoanal polyps is recur-
rence, which has been noted after limited surgical pro-
cedures such as polypectomy. Complete removal either
endoscopically or through a Caldwell-Luc approach has
been shown to minimize the likelihood of recurrence
of the polyp in adults and children. The advantage of
these techniques is that the polyp and involved antral
mucosa are removed as a unit under direct visualiza-
tion, thereby preventing any possibility of recurrence.
Precise surgery targeted to the maxillary sinus with
removal of only a small amount of sinus mucosa at the
stalk insertion site is facilitated by endoscopic visualiza-
tion. Bleeding is minimal and packing obviated. Tem-
porary hypoesthesia of the infraorbital nerve can occur
even with a canine fossa puncture, and patients should
be counseled about this complication.
References
1. Kamath MP, Hegde MC, Sreedharan S, Padmanabhan K: Antro-
choanal polyps and allergy—a comparative study. Indian J Otolar-
yngol Head Neck Surg 54:7-12, 2002.
2. Magit AE: Tumors of the nose, paranasal sinuses and nasopharynx.
In Bluestone CD, Stool SE (eds): Pediatric Otolaryngology, 4th ed.
Philadelphia, WB Saunders, 2003, pp 1054-1055.
3. Christmas DA, Yanagisawa K, Yanagisawa E: Antrochoanal polyp
displacing the uvula and the soft palate. Ear Nose Throat J 82:347-
348, 2003.
4. Cook PR, Davis WE, McDonald R, McKinsey JP: Antrochoanal
polyps: A review of 33 cases. Ear Nose Throat J 72:404-410, 1993.
5. Schramm VL Jr, Effron MZ: Nasal polyps in children. Laryngo-
scope 90:1488-1495, 1980.
6. Loury MC, Hinkley DK, Wong W: Endoscopic transnasal antrocho-
anal polypectomy: An alternative to the transantral approach.
South Med J 86:18-22, 1993.
7. Ozdek A, Samim E, Bayiz U, et al: Antrochoanal polyps in children.
Int J Pediatr Otorhinolaryngol 65:213-218, 2002.
Figure 17-3. A specimen demonstrating the polyp (right) and the
mucosa of the maxillary antrum (left) as a unit.
PEARLS
• An antrochoanal polyp enters the nose via an
accessory ostium in the posterior fontanelle of the
maxillary sinus, but it does not usually have to be
connected to the natural ostium.
• Removal of an antrochoanal polyp generally requires
a large maxillary antrostomy, angled telescopes, and
sometimes a canine fossa puncture.
PITFALLS
• Perform a careful offi ce endoscopic examination to
rule out an inverted papilloma.
• Beware of a lesion that does not exit the maxillary
sinus through an accessory ostium.
• The patient should be completely informed of the
possibility of infraorbital hypoesthesia from a canine
fossa puncture.
• Precise and complete removal is the only way to
avoid recurrence.
• All material processed though the powered
instrument should be collected in a specimen sock
and sent to the pathology department to avoid an
error in diagnosis.
• A soft tissue shaver is very useful for all aspects of
antrochoanal polyp removal; however, the whole
lesion does not have to be processed through the
device.
• Specimens too large to be removed through the
nose can be extracted transorally.
• Long curved frontal sinus instruments are sometimes
useful for reaching the stalk of the lesion.

Management of
Complications of Endoscopic
Sinus Surgery
Chapter 18
Complications of Endoscopic Sinus
Surgery: CSF Leak
Ricardo L. Carrau, Carl H. Snyderman, and Amin B. Kassam
A cerebrospinal fl uid (CSF) leak involves a communica-
tion between the arachnoid space and the sinonasal
tract; this implies the trespassing of the mucoperios-
teum, the cranial bone, dura mater, and the arachnoid
(Fig. 18-1). The etiology of CSF leaks can be divided
into post-traumatic and spontaneous. Post-traumatic
CSF leaks are by far the most common and these include
postaccidental injuries such as closed-head injuries
with and without skull base fractures and surgery.1-3 Of
interest for the otolaryngologist are those CSF leaks
produced during endoscopic sinus surgery. Although
the incidence of CSF leaks after endoscopic sinus
surgery is less than 1% due to the high volume of sur-
geries, this still remains one of the most common
causes.4-21
Immediate identifi cation and repair of a CSF leak
avoids development of life-threatening complications.1,2
Intraoperatively, the surgeon may identify a source of
clear fl uid and/or the pulsating dura or brain. Postop-
eratively, patients with CSF leaks present with symptoms
such as clear nasal discharge associated with headache
or complications such as pneumocephalus, meningitis,
or brain abscess. A highly reliable way of corroborating
a CSF leak is the use of a β2 transferrin test. β2 transfer-
rin is a protein that exists in CSF, in perilymph, and in
ocular humors. This protein can be detected using elec-
trophoretic techniques, and its presence corroborates
a CSF leak. The test is highly specifi c and highly sensi-
tive and only a minimal volume is necessary to detect
the protein. Detection of β trace protein has been
reported recently and seems to be a better test than the
β2 transferrin. It has the same advantages of the β2
transferrin test but it can be performed faster and is less
costly. Patients with renal disease, however, may present
with elevation of the beta trace protein level and patients
with meningitis may have a lower level, leading to a
false-positive or false-negative result, respectively. Direct
endoscopic visualization may identify the site of a CSF
leak and in these cases the corroboration by β2 transfer-
rin or β trace is unnecessary. The use of intrathecal
fl uorescein may be used as an alternative. Despite
known side effects, fl uorescein is safe when injected in
the intrathecal space at a low concentration (less than
5%) and low volume (5 mL). In our practice, however,
we rarely use fl uorescein because the logistics of per-
forming a lumbar puncture in the otolaryngology offi ce
precludes its use. In addition, there is a medicolegal
concern due to the warning on the fl uorescein label,
which states that it is not for intrathecal use. Nonethe-
less, the European and American literature supports its
use when indicated and corroborates its usefulness.
Imaging is useful to identify the presence of a
skull base defect and to stage its site and size. A high-
resolution computed tomography (CT) scan using both
coronal and axial views with a bone algorithm is the
preferred technique for the initial evaluation. The skull
base defect is better visualized when the area is scanned
at an angle perpendicular to the defect. In other words,
defects at the ethmoid roof are better seen in the
coronal CT scan, whereas defects of the posterior wall
of the frontal sinus are better shown in the axial CT
scan. In our practice, patients with a negative CT scan
131

132
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
undergo a CT cisternography. This involves the intra-
thecal injection of contrast at the same time of a high-
resolution CT scan. If this test fails to identify a skull
base defect, 10 mL of normal saline solution is injected
into the intrathecal space to increase the CSF pressure,
and, therefore, to increase the sensitivity of the test by
inducing an active leak. Although some advocate an MR
cisternography, our experience with this technique has
yielded mixed results. We recommend magnetic reso-
nance imaging (MRI) when the patient presents with a
meningoencephalocele to better assess the contents of
the sac and in those patients who present with brain
injury. It is important to understand the nature of the
contents within a meningocele or meningoencephalo-
cele, in that we have encountered critical vascular struc-
tures within the sac. This has an important therapeutic
implication because, most of the time, this sac is tran-
sected and discarded, and not reduced back into the
intracranial space.
Once the skull base defect has been adequately
staged, the patient can be taken to the operating room
for repair. Multiple techniques have been reported for
the repair of a CSF leak. In 1952, Hirsch described the
fi rst endonasal repair of CSF leak using a septal fl ap.22
Subsequently, Montgomery described his experience
using septal fl aps through an external nasal approach
to treat CSF leak.23 In 1976, McCabe reported his expe-
rience with the use of osteomucoperiosteal fl aps from
the septum or middle turbinate through an external
ethmoidectomy approach.24 In 1989, a publication of
McCabe’s updated experience reported a 100% closure
rate with a follow-up of 1.6 to 22 years.25 The use of
these and other local fl aps to treat CSF leaks via an
endoscopic approach was subsequently reported.13,26
In 1985, Calcaterra27 described the use of free
muscle or fascia grafts to treat CSF leaks using an exter-
nal ethmoidectomy approach, and in 1989 Papay and
colleagues28 described an endoscopic technique. Multi-
ple publications followed, reporting the use of free
grafts and/or local fl aps for the repair of CSF leak.
Recently, a vascularized nasoseptal fl ap has been devised
to reconstruct skull base defects of various etiologies
and early follow-up data reveal a remarkable improve-
ment in controlling large CSF leaks, such as those asso-
ciated with expanded endonasal approaches to the
skull base.29
The most predominant factors infl uencing the
choice of which technique and material are used during
the endoscopic endonasal closure of CSF leaks are the
availability of the biologic material and the experience
and familiarity of the operating surgeon with various
techniques. Most techniques yield similar results in
experienced hands, as confi rmed by a meta-analysis of
the literature by Hegazy and colleagues.1 After analyz-
ing all reports in the English literature comprising a
series of endoscopic repairs of more than fi ve patients,
this study found no signifi cant differences in outcome,
regardless of which surgical technique or which homol-
ogous material was used for the repair.
PATIENT SELECTION
The diagnosis and management of a CSF leak involves
three critical steps: distinguishing a CSF leak from other
sources of rhinorrhea, locating the leak, and ruling out
high intracranial pressure secondary to altered CSF
dynamics.
A clinical diagnosis of a CSF leak is based on a
history of clear, watery nasal drainage, usually unilat-
eral, and commonly associated with headache. Increased
rhinorrhea when the patient leans over, tilts the head
forward, or performs a Valsalva maneuver further sug-
gests the presence of a CSF leak. A life-threatening
complication arising from the CSF leak, such as pneu-
mocephalus, brain abscess, or ascending bacterial men-
ingitis may be the initial presentation.
Conditions such as vasomotor rhinitis and sympa-
thetic denervation can cause profuse rhinorrhea that
may be confused with a CSF leak. Nasal irrigations
during endoscopic sinus surgery or used for nasal
hygiene postoperatively may accumulate in the parana-
sal sinuses and later present as postoperative rhinor-
rhea. Thus biochemical testing is indicated to confi rm
the true nature of the nasal drainage. CSF is high in
glucose and low in protein. However, normal nasal dis-
charge has been shown to be falsely positive for glucose
in 45% to 75% of cases.30 β2 transferrin is a protein
found in CSF, aqueous humor, and perilymph, but not
in blood or nasal secretions; therefore β2 transferrin is
a reliable chemical marker of CSF leakage.31-35 As previ-
ously mentioned, β-trace protein seems to be superior
to β2 transferrin as a chemical marker for a CSF
leak.36
PREOPERATIVE PLANNING
When CSF leak develops after sinus surgery, the endo-
scopic surgeon typically has an impression as to the
possible site of injury to the cranial base (i.e., site of the
CSF leak).
Pia/Brain
Arachnoid
Dura mater
Cranial bone
Mucoperiosteum
Definition
Figure 18-1. Schematic representation of a CSF leak to the sinona-
sal tract.

Chapter 18
Complications of Endoscopic Sinus Surgery: CSF Leak
133
Therefore a thorough endoscopic offi ce examina-
tion of the nasal cavity may corroborate the site of the
leakage. Fistulas with low-pressure leaks are diffi cult to
identify, especially in the presence of postoperative
tissue edema and blood clots.
Intrathecal injection of contrast materials and
radioactive tracers has been advocated to confi rm a CSF
leak and to identify the site of origin. Intrathecal fl uo-
rescein may be used to aid in the diagnosis and localiza-
tion of the CSF leak. During this test, 0.5 mL of
fl uorescein, of a concentration not greater than 5%, is
diluted with 10 mL of CSF, obtained through a lumbar
puncture, and is then injected intrathecally. Fluores-
cein is neurotoxic and a low concentration–low volume
injection is mandatory to avoid the neurologic compli-
cations associated with higher concentrations. After
intrathecal injection of the fl uorescein solution,
the CSF leak may be visualized using the nasal endo-
scope.31-35,37 Under a Wood lamp (i.e., black light), fl uo-
rescein appears as bright yellow-green; nonetheless, the
yellowish color of fl uorescein may be identifi ed without
the need for special lighting.
Logistics of performing a lumbar puncture in an
outpatient setting and medicolegal considerations
(fl uorescein drug package insert includes an advisory
warning against intrathecal use) have discouraged us
from its use. Intrathecal injections, in any case, are
rarely critical to the identifi cation of the CSF leak
caused by endoscopic sinus surgery.
Others have advocated the intrathecal injection of
air, which can “bubble” out at the fi stula site, thus aiding
in its identifi cation.37 Air, however, is an irritant to the
brain and may induce seizures. Normal saline solution
may be injected into the intrathecal space to increase
the pressure within the subarachnoid space and thus
aid in the identifi cation of the leak.
Scintigraphy with indium (In-111) has been advo-
cated for the identifi cation of a CSF leak. Radiotracing is
a very sensitive test, but it is associated with a high false-
positive rate31 and has a poor resolution that precludes
establishing the specifi c point of leakage. In general, we
do not advocate scintigraphy. In our practice, the pres-
ence of the CSF leak is validated with β2 transferrin elec-
trophoresis. CT, MRI, CT cisternography, and/or
endoscopy are used to identify the site of origin.
Imaging is critical to locate the site of the leak and
estimate its size. High-resolution CT (HRCT) is our
preferred initial imaging study to aid in the identifi ca-
tion of the site of injury and its extent. HRCT with
contrast also provides information about the possibility
of intracranial complications, such as hematoma or
brain contusion, that occur in the setting of acute
trauma (iatrogenic or accidental). HRCT with views
taken at a perpendicular plane from the suspected site
of injury better evaluates the integrity of the bony wall
in question. Coronal CT views are best to evaluate
defects of the cribriform plate, fovea ethmoidalis, or
planum sphenoidale, whereas axial views are superior
to evaluate the posterior wall of the frontal or sphenoid
sinuses. We use MRI to ascertain the contents of menin-
gocele or meningoencephalocele.
HRCT, however, may not identify small areas of
surgical trauma or linear nondisplaced fractures. In this
case, HRCT can be used in conjunction with intrathecal
contrast to identify the leak. CT cisternography has
been documented to be both sensitive and reliable.
Water-soluble nonionic contrast materials with less tox-
icity, headache, nausea, and arachnoiditis have replaced
metrizamide. Identifi cation of the leak using contrast
studies, however, requires the presence of an active
leak. Intermittent leaks that are temporarily sealed by
swelling, infl ammation, or brain herniation may yield a
false-negative result. Intrathecal injection of saline solu-
tion to increase the CSF pressure, “a saline challenge,”
enhances the sensitivity of the test.
Others have suggested MR cisternography to com-
plement the information offered by an HRCT without
the need for intrathecal contrast.38 In our experience
however, this technique has yielded inconsistent
results.
SURGICAL TECHNIQUE
Ethmoid Sinus Roof and Cribriform Plate
If a CSF leak is suspected during endoscopic sinus
surgery, all overlying mucosa should be refl ected away
from the defect to closely examine the area and to
determine the extent of injury. Exposure of the entire
defect is essential. In fact, exposure of the defect may
be a more important factor determining the success of
the repair than size or site.39-41 It should be emphasized
that for the graft to take, the defect should be prepared
and there should be a denuded area that facilitates
contact of the graft with the skull base.
An inlay or onlay free tissue graft may be used to
patch the site of injury (Fig. 18-2 through 18-4). Fascia
lata, temporalis muscle, abdominal fat, septal or middle
turbinate mucosa or composite grafts, periosteum, and
perichondrium are suitable grafting tissues. When pos-
sible, the dura is elevated around the edges of the defect
using a small elevator and the graft is inserted between
the dura and the bone of the skull base, that is, an epi-
dural inlay graft (see Fig. 18-2). Alternatively, the dura
may be separated from the brain and the inlay graft may
Pia/Brain
Arachnoid
Dura mater
Cranial bone
Mucoperiosteum
Inlay Graft: Epidural
Figure 18-2. Schematic representation of an inlay epidural free
graft.

134
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
vascularized pedicle fl ap using the mucoperiosteum of
the inferior turbinate has been described also.45
Sphenoid Sinus
CSF leaks involving the sphenoid sinus are amenable to
a repair that includes obliteration of the sinus. The
sphenoid sinus can be approached transseptally, trans-
ethmoidally, or through a direct endoscopic approach
such as the one described for pituitary surgery.46 After
proper identifi cation of surgical landmarks (e.g., the
carotid canal, optic nerve canal, and optic carotid
recesses) and establishing the extent of the defect iden-
tifying the leak, the sinus mucosa is thoroughly removed.
Onlay or inlay free tissue grafts are placed and the sinus
Pia/Brain
Arachnoid
Dura mater
Cranial bone
Mucoperiosteum
Inlay Graft: Subdural
Figure 18-3. Schematic representation of an inlay subdural free
graft.
Pia/Brain
Arachnoid
Dura mater
Cranial bone
Mucoperiosteum
Onlay Graft
Figure 18-4. Schematic representation of an onlay free graft.
be placed in the subdural space (see Fig. 18-3). When
an inlay graft is not possible due to technical diffi culties
or because the leak involves a linear fracture that does
not expose the dural defect, or because dissection of
the dura may risk neurovascular structures, the graft is
placed as an onlay over the defect, outside the cranial
cavity (see Fig. 18-4). Free muscle or fat grafts can also
be used as a dumbbell or “bath plug” graft (Fig. 18-5).42
Fibrin glue, platelet rich serum, or other biologic glue
may be used to increase the adhesiveness of the muscle
or fascia graft.
The graft is supported in place with layers of
Gelfoam/Gelfi lm (Upjohn Co., Kalamazoo, MI), fol-
lowed by a sponge packing or bacitracin-impregnated
gauze. Gelfoam and/or Gelfi lm prevent adherence of
the packing to the graft, thus preventing accidental
avulsion of the graft when the packing is removed 3 to
7 days after the surgery.
Alternatively, a vascularized tissue fl ap may be
designed and harvested transnasally using mucoperi-
chondrium from the middle turbinate or septum.
Recently we have been using the Hadad-Bassagasteguy
fl ap, which consists of a septal mucoperichondrial/
mucoperiosteal fl ap based on the posterior septal artery
(Figs. 18-6 through 18-8).43,44 The entire mucoperichon-
drium/mucoperiosteum may be harvested on one side
to cover very large defects of the skull base. Another
Pia/Brain
Arachnoid
Dura mater
Cranial bone
Mucoperiosteum
Bath Plug Graft
Figure 18-5. Schematic representation of a “bath plug” free graft.
Figure 18-6. Schematic representation of the incisions for a pedi-
cled nasoseptal fl ap. The superior incision is placed 1 to 2 cm below
the level of the olfactory sulcus. The inferior incision is placed at the
level of the maxillary crest or at the fl oor of the nose. An anterior
vertical incision joins the two parallel horizontal incisions. Posteriorly
the superior incision extends to cross the rostrum of the sphenoid
sinus at the level of its natural ostium. The inferior incision extends
following the posterior free edge of the septum and crosses the pos-
terior choana to reach the lateral wall of the nose.

Chapter 18
Complications of Endoscopic Sinus Surgery: CSF Leak
135
is then obliterated with abdominal free fat (Fig. 18-9).
Anteriorly, the exposed fat is covered with a layer of
Surgicel followed by Gelfi lm, and the nose is packed
with 1–2 -inch nasal strip that has been impregnated with
antibiotic ointment.
An intraoperative CSF leak arising from the sella
turcica during pituitary surgery most often can be
repaired by obliterating the sella with free fat and
reconstructing the fl oor of the sella with a free bone
or cartilage graft harvested during the endoscopic
approach.41 Thus it does not require postoperative
packing or the removal of the entire mucoperiosteum
of the sinus.
The previously described Hadad fl ap has been very
effective to repair these defects.
Risk of accidental injury to adjacent neurovascular
structures is a critical consideration when dealing with
defects at the lateral wall of the sphenoid sinus. Ade-
quate visualization of this area is mandatory.
Frontal Sinus
CSF leaks involving the nasofrontal recess often require
an extended sinusotomy to adequately expose and
repair the defect while preserving the drainage pathway.
The Draf III approach,47 which involves medial widen-
ing of the frontal recesses and removal of the superior
nasal septum and inferior frontal sinus septum, pro-
vides an adequate exposure of leaks around the fronto-
nasal recess, thus allowing an endoscopic repair.
POSTOPERATIVE MANAGEMENT
General Principles
As previously mentioned, the general principles of man-
aging a CSF leak include adjunctive measures that may
facilitate healing of the repair, including avoidance of
activities that raise the intracranial pressure, such as
straining, leaning forward, or lifting objects greater
than 15 lb. Other measures include bed rest, stool soft-
eners, 30- to 45-degree elevation of the head of bed,
sneezing with an open mouth, and absolute avoidance
of nose blowing. “Deep extubation” is used to prevent
straining and coughing, and positive pressure mask ven-
tilation is contraindicated.
The use of prophylactic antibiotics for the preven-
tion of meningitis in patients with CSF leaks is contro-
versial. The routine use of antibiotics for traumatic CSF
leaks is not of proven effi cacy and are thought too select
for resistant bacteria. However, the use of antibiotics
when the patient has an active sinus infection is war-
ranted. We do, however, favor the use of perioperative
prophylactic antibiotics during the repair of the CSF
leak. Antibiotics are continued until nasal packing is
removed.
Figure 18-7. Schematic representation of elevation of the nasosep-
tal fl ap following a subperichondrial/subperiosteal plane.
Figure 18-8. Schematic representation of reconstruction of the
skull base mobilizing a pedicled nasoseptal fl ap.
Pia/Brain
Arachnoid
Dura mater
Cranial bone
Mucoperiosteum
Obliteration
Figure 18-9. Schematic representation of fat obliteration.

136
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
A postoperative CT scan without contrast within the
fi rst 24 hours after surgery is important to rule out evi-
dence of intracranial bleeding, parenchymal injury, or
tension pneumocephalus. We favor a routine CT scan
of the brain, even in the absence of any neurologic
defi cit.
In our practice we work in conjunction with a neu-
rosurgical team during the repairs. Although we do not
consider it necessary in all cases, neurosurgical consul-
tation provides an important perspective on intraopera-
tive and postoperative management, especially on the
need for a CSF drain or a shunt. A lumbar drain is
helpful to control intracranial pressure with a desig-
nated amount of CSF removed daily based on CSF pro-
duction, but it is only used for those patients suspected
of having high-pressure hydrocephalus; thus we do
not advocate its routine use for CSF leaks produced
by endoscopic sinus surgery. Overdrainage should be
avoided, because this creates a negative intracranial
pressure (i.e., suction effect) that may result in pneu-
mocephalus and promote bacterial contamination of
the CSF with resultant meningitis.
Nasal irrigations with nasal saline solution and
gentle débridement of crusting are started 1 week
postoperatively.
2. Bernal-Sprekelsen M, Bleda-Vazquez C, Carrau RL: Ascending
meningitis secondary to traumatic cerebrospinal fl uid leaks. Am
J Rhinol 14:257-259, 2000.
3. Bernal-Sprekelsen M, Alobid I, Mullol J, et al: Closure of cerebro-
spinal fl uid leaks prevents ascending bacterial meningitis. Rhinol-
ogy 43(4):277-281, 2005.
4. Wigand ME: Transnasal ethmoidectomy under endoscopic
control. Rhinology 19:7-15, 1981.
5. Hoffman DF, May M: Endoscopic sinus surgery—Experience with
the initial 100 patients. Trans Pa Acad Ophthalmol Otolaryngol
41:847-850, 1989.
6. Kainz J, Stammberger H: The roof of the anterior ethmoid: A
place of least resistance in the skull base. Am J Rhinol 3:191-199,
1989.
7. Benninger MS, Mickelson SA, Yaremchuk K: Functional endo-
scopic sinus surgery: Morbidity and early results. Henry Ford
Hosp Med J 38:5-8, 1990.
8. Levine HL: Functional endoscopic sinus surgery: Evaluation,
surgery, and follow-up. Laryngoscope 100:79-84, 1990.
9. Sterman BM, DeVore RA, Lavertu P, Levine HL: Endoscopic
sinus surgery in a residency training program. Am J Rhinol 4:207-
210, 1990.
10. Duplechain JK, White JA, Miller RH: Pediatric sinusitis. The role
of endoscopic sinus surgery in cystic fi brosis and other forms of
sinonasal disease. Arch Otolaryngol Head Neck Surg 117:422-
426, 1991.
11. Salman SD: Complications of endoscopic sinus surgery. Am J
Otolaryngol 12:326-328, 1991.
12. Wigand ME, Hosemann WG: Results of endoscopic surgery of the
paranasal sinuses and anterior skull base. J Otolaryngol 20:385-
390, 1991.
13. Stankiewicz JA: Cerebrospinal fl uid fi stula and endoscopic sinus
surgery. Laryngoscope 101:250-256, 1991.
14. Vleming M, Middelweerd RJ, de Vries N: Complications of endo-
scopic sinus surgery. Arch Otolaryngol Head Neck Surg 118:617-
623, 1992.
15. Freedman HM, Kern EB: Complications of intranasal ethmoidec-
tomy: A review of 1,000 consecutive operations. Laryngoscope
89:421-434, 1979.
16. Eichel BS: The intranasal ethmoidectomy: A 12-year perspective.
Otolaryngol Head Neck Surg 90:540-543, 1982.
17. Stevens HE, Blair NJ: Intranasal sphenoethmoidectomy: 10-year
experience and literature review. J Otolaryngol 17:254-259,
1988.
18. MacKay IS: Endoscopic sinus surgery—Complications and how to
avoid them. Rhinol 14(suppl):151-155, 1992.
19. Friedman WH, Katsantonis GP: Intranasal and transantral eth-
moidectomy: A 20-year experience. Laryngoscope 100:343-348,
1990.
20. Cumberworth VL, Sudderick RM, Mackay IS: Major complica-
tions of functional endoscopic sinus surgery. Clin Otolaryngol
19:248-253, 1994.
21. Kennedy DW, Shaman P, Han W, et al: Complications of eth-
moidectomy: A survey of fellows of the American Academy of
Otolaryngology—Head and Neck Surgery. Otolaryngol Head
Neck Surg 111:589-599, 1994.
22. Hirsch O Successful closure of cerebrospinal fl uid rhinorrhea by
endonasal surgery. Arch Otolaryngol 56:1-13, 1952.
23. Montgomery WW. Cerebrospinal rhinorrhea. Otolaryngol Clin
North Am 6:757-771, 1973.
24. McCabe BF. The osteo-muco-periosteal fl ap in repair of
cerebrospinal fl uid rhinorrhea. Laryngoscope 86:537-539,
1976.
25. Yessenow RS, McCabe BF: The osteo-mucoperiosteal fl ap in
repair of cerebrospinal fl uid rhinorrhea: A 20-year experience.
Otolaryngol Head Neck Surg 101:555-558, 1989.
26. Mattox DE, Kennedy DW: Endoscopic management of cerebro-
spinal fl uid leaks and cephaloceles. Laryngoscope 100:857-862,
1990.
27. Calcaterra TC: Diagnosis and management of ethmoid cerebro-
spinal rhinorrhea. Otolaryngol Clin North Am 18:99-105, 1985.
28. Papay FA, Maggiano H, Dominquez S, et al: Rigid endoscopic
repair of paranasal sinus cerebrospinal fl uid fi stulas. Laryngo-
scope 99:1195-1201, 1989.
PEARLS
• Early repair of a CSF leak prevents life-threatening
complications.
• CSF leaks resulting as a complication of endoscopic
sinus surgery are not likely to heal with conservative
management and thus require surgical repair.
• Endoscopic repair is the preferred approach.
• β2 transferrin and β trace protein are reliable
markers for a CSF leak.
• A high-resolution CT is the preferred imaging
technique to localize and stage defects that are
suspected postoperatively.
PITFALLS
• Common causes for a failed repair of a CSF leak
repair are inadequate exposure or inadequate
postoperative management.
• Inappropriate concentration of intrathecal
fl uorescein administration can lead to neurologic
sequelae.
• Positive pressure ventilation should be avoided in
the immediate postoperative period to prevent
pneumocephalus.
References
1. Hegazy HM, Carrau RL, Snyderman CH, et al: Transnasal-endo-
scopic repair of cerebrospinal fl uid rhinorrhea: A meta-analysis.
Laryngoscope 110:1166-1172, 2000.

Chapter 18
Complications of Endoscopic Sinus Surgery: CSF Leak
137
29. Hadad G, Bassagasteguy L, Carrau RL, et al: A novel reconstruc-
tive technique after endoscopic expanded endonasal approaches:
Vascular pedicle nasoseptal fl ap. Laryngoscope 116:1882-1886,
2006.
30. Yamamoto Y, Kunishio K, Sunami N, et al: Identifi cation of CSF
fi stulas by radionuclide counting. AJNR 11:823-826, 1990.
31. Oberascher G, Arrer E: Effi ciency of various methods of identify-
ing cerebrospinal fl uid in oto- and rhinorrhea. ORL 48:320-325,
1986.
32. Fransen P, Sindic CSM, Thavroy C, et al: Highly sensitive detec-
tion of beta-2 transferrin in rhinorrhea and otorrhea as a marker
for cerebrospinal fl uid (C.S.F.) leakage. Acta Neurochir (Wein)
109:98-101, 1991.
33. Oberascher G: Cerebrospinal fl uid otorrhea—New trends in
diagnosis. Am J Otol 9:102-108, 1988.
34. Oberascher G: A modern concept of cerebrospinal fl uid diagno-
sis in oto- and rhinorrhea. Rhinology 26:89-103, 1988.
35. Skedros DG, Cass SP, Hirsch BE, Kelly RH: Sources of error in
use of beta-2 transferrin analysis for diagnosing perilymphatic
and cerebral spinal fl uid leaks. Otolaryngol Head Neck Surg
109:861-864, 1993.
36. Meco C, Oberascher G, Arrer E, et al: Beta-trace protein test: New
guidelines for the reliable diagnosis of cerebrospinal fl uid fi stula.
Otolaryngol Head Neck Surg 129(5):508-517, 2003.
37. Kelly TF, Stankiewicz JA, Chow JM, et al: Endoscopic closure of
postsurgical anterior cranial fossa cerebrospinal fl uid leaks. Neu-
rosurg 39:743-746, 1996.
38. Sillers MJ, Morgan CE, Gammal TE: Magnetic resonance cister-
nography and thin coronal computerized tomography in the
evaluation of cerebrospinal fl uid rhinorrhea. Am J Rhinol 11:387-
392, 1997.
39. Weber R, Keerl R, Draf W, et al: Management of dural lesions
occurring during endonasal sinus surgery. Arch Otolaryngol
Head Neck Surg 122:732-736, 1996.
40. Castelnuovo PG, Delu G, Locatelli D, et al: Endonasal endoscopic
duraplasty: Our experience. Skull Base 16(1):19-24, 2006.
41. Zweig JL, Carrau RL, Celin SE, et al: Endoscopic repair of
acquired encephaloceles, meningoceles, and meningo-encepha-
loceles: Predictors of success. Skull Base 12(3):133-139, 2002.
42. Wormald PJ, McDonogh M: The bath-plug closure of anterior
skull base cerebrospinal fl uid leaks. Am J Rhinol 17(5):299-305,
2003.
43. Hadad G, Bassagasteguy L, Carrau RL, et al: A novel reconstruc-
tive technique after endoscopic expanded endonasal approaches:
Vascular pedicle nasoseptal fl ap. Laryngoscope 116(10):1882-
1886, 2006.
44. Pinheiro-Neto CD, Prevedello DM, Carrau RL, et al: Improving
the design of the pedicled nasoseptal fl ap for skull base recon-
struction: A radioanatomic study. Laryngoscope 117:1329-1332,
2007.
45. Fortes FS, Carrau RL, Snyderman CH, et al: The posterior pedicle
inferior turbinate fl ap: A new vascularized fl ap for skull recon-
struction. Laryngoscope 117:1560-1569, 2007.
46. Al-Nashar IS, Carrau RL, Herrera A, Snyderman CH: Endoscopic
transnasal transpterygopalatine fossa approach to the lateral
recess of the sphenoid sinus. Laryngoscope 114(3):528-532,
2004.
47. Weber R, Draf W, Kratzsch B, et al: Modern concepts of frontal
sinus surgery. Laryngoscope 111(1):137-146, 2001.

Chapter 19
Orbital Complications of Endoscopic
Sinus Surgery
Berrylin J. Ferguson
The usual chapter headings of patient selection and
preoperative preparation are not applicable to this
chapter on orbital complications. One does not select
a patient to have an orbital complication. Far preferable
to managing a complication is prevention of the com-
plication. In Chapter 12, the dangers of the micro-
débrider are outlined. Microdébriders can cause
irreparable diplopia because of injury to the extraocu-
lar muscles. Other complications include retrobulbar
hemorrhage from injury to the anterior ethmoid artery.
Prompt recognition and decompression of the orbit are
required. Surgery on the sphenoid and posterior
ethmoid sinuses may cause injury to the optic nerve,
which is exposed in more than 20% of cases. Failure to
appreciate an exposed optic nerve or a bony dehiscence
over the optic nerve preoperatively may lead to blind-
ness. Rarely, infection or orbital emphysema may com-
plicate endoscopic sinus surgery (ESS). This chapter
discusses these various complications and highlights
recommendations for prevention, followed by tech-
niques for management.
MICRODÉBRIDER AND
ORBITAL COMPLICATIONS
Microdébriders have revolutionized ESS. They suction
and then cut tissue. Unfortunately, this can lead to an
increased complication rate, particularly with novice
surgeons. True cutting instruments or even forceps
allow the surgeon to more easily identify the tissue
removed. Because of the suction and cutting aspects of
the microdébrider, aspiration and removal of inappro-
priate tissue occur much more rapidly and potentially
without identifi cation of the tissue. The most frequent
adverse outcome of use of the microdébrider is injury
to the medial rectus muscle. No satisfactory corrective
intervention has been established for this complication
to date.1 Similarly, although less common, intracranial
complications can be caused by aspiration of dura or
cranial contents.
To prevent orbital complications, the microdé-
brider should not be used adjacent to the lamina papy-
racea by an inexperienced surgeon. It is particularly
risky to use the microdébrider adjacent to areas of bony
dehiscence of the orbital wall. Safety of the micro-
débrider is enhanced by directing the mouth of the
opening medially and not laterally. Frequent palpation
of the eye will allow early identifi cation of the orbit
endoscopically.
RETROBULBAR HEMORRHAGE
The anterior ethmoid artery, a branch of the ophthal-
mic artery, traverses the lamina papyracea across the
ethmoid cavity just behind the frontal recess before re -
entering the cranially cavity in the cribriform fossa. If
the artery is sectioned in the ethmoid fossa and retracts
into the orbit, a retrobulbar hemorrhage can occur. If
a retrobulbar hemorrhage does occur, the eye will
become proptotic and much fi rmer by palpation. Gently
palpating the eyes before sinus surgery will give the
surgeon a baseline for orbital fi rmness with which to
compare if a retrobulbar hemorrhage occurs. The eyes
should be visible to the surgeon during the procedure
and not obscured with drapes, although tape to keep
the eyes closed is acceptable. In the event of retrobulbar
hemorrhage, orbital pressure must be assessed. If it
becomes elevated, the orbit should be decompressed.
Decompression should not be postponed to have an
ophthalmologist evaluate orbital pressure. If ophthal-
mologic consultation is not readily available and there
is a high probability of increased intraocular pressure,
139

140
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
the orbit should be decompressed. The fastest and
easiest method of decompression is a lateral canthot-
omy with inferior cantholysis (Figs. 19-1 and 19-2). If
the patient is conscious, 0.5 to 1.0 mL of lidocaine
(Xylocaine) with 1:100,000 epinephrine is injected into
the lateral canthus. A small hemostat is placed horizon-
tally across the lateral canthus, the tissue is crushed, and
then a 10-mm horizontal cut with sharp scissors is made
in the crush mark. The scissors are then directed infe-
riorly until the bony rim of the orbit is felt, and the
inferior cantholysis is performed. The lateral canthal
tendon can also be isolated by dissecting it free from
the conjunctiva posteriorly and from the skin anteri-
orly. The inferior crus of the lateral canthal tendon is
then disinserted completely so that the lower lid is
totally mobile. The orbit is not decompressed until the
lower lateral canthal tendon is cut. It is important to
not perform this procedure on the upper lid because
the lacrimal gland and levator muscle can be damaged.
The lateral canthal incision can be closed at a later date
with 7-0 Vicryl or left to heal on its own. A lateral can-
thotomy and cantholysis are performed immediately to
decompress the orbit, and are usually suffi cient to
prevent irreversible ocular changes.2
COMPLICATIONS OF THE SPHENOID AND
POSTERIOR ETHMOID SINUS AND ORBIT
In an incompletely opacifi ed sinus, delineation of the
optic nerve is easier on computed tomography (CT)
than in an opacifi ed sinus. The frequency of complete
dehiscence of the optic nerve in the sphenoid sinus is
6%, and an additional 3% are immediately adjacent to
the sphenoid sinus and the posterior ethmoid cell (an
Onodi cell) (Figs. 19-3 and 19-4). Bone dehiscence over
the medial aspect of the optic nerve is more common
and occurs collectively in almost 25% of patients. In all
patients in whom such dehiscences occur and in patients
in whom it is diffi cult to assess because of opacifi cation
of the sphenoid, microdébriders should either not be
used or be used so that all tissue comes into the micro-
débrider in a direction that would preclude injury to
the optic nerve. Cutting instruments and forceps should
be used only with direct visualization in these areas and
not blindly. There is no treatment of a transected optic
nerve.
POSTOPERATIVE ORBITAL INFECTIONS
Orbital abscesses can occur postoperatively, and post-
operative orbital swelling demands evaluation of vision
and extraocular movement. If the swelling precludes
Figure 19-1. Lateral canthotomy is performed to immediately
decompress the orbit.
Figure 19-2. Decompression is not complete until the lower lateral
crus is cut via cantholysis.
Figure 19-3. Coronal sinus computed tomography scan demon-
strating a dehiscent left optic nerve (arrow).

Chapter 19
Orbital Complications of Endoscopic Sinus Surgery
141
such evaluation, an immediate sinus CT scan should be
obtained along with ophthalmologic consultation. This
will conclusively distinguish preseptal from postseptal
swelling. Management is similar to that for increased
ocular pressure from a retrobulbar hemorrhage and
consists of urgent decompression, initially with lateral
canthotomy and cantholysis. In addition, Gram stain
and aerobic/anaerobic culture are carried out, and
empirical intravenous antibiotics directed at the usual
acute pathogens are initiated. Figure 19-5 presents a CT
scan of a patient with an orbital abscess and increased
intraocular pressure 3 days after ESS. The patient
underwent endoscopic decompression but remained
blind because of the prolonged duration of increased
orbital pressure (Fig. 19-6). Whether administration of
antibiotics intraoperatively or postoperatively would
prevent this rare complication is unknown. Certainly, if
a patient has evidence of acute and active infection at
the time of surgery, culture should be performed and
antibiotics given intraoperatively and postoperatively to
cover the usual acute pathogens.
SUBCUTANEOUS EMPHYSEMA
If a patient sneezes or blows the nose in the immediate
postoperative period and there is a hole in the lamina
papyracea, air can be forced into the tissues of the orbit
and face. Gentle ballottement of the eye may actually
increase subcutaneous emphysema by creating a ball-
valve effect and pump additional air into the subcutane-
ous tissue (Figs. 19-7 and 19-8). In general, the
emphysema will resolve with watchful waiting without
intervention. Rarely, the intraorbital air mass can cause
central retinal artery occlusion. An early indicator of
visual loss is loss of the ability to see the color red. One
case of blindness secondary to orbital emphysema
occurred 48 hours after ESS and was initiated by sneez-
ing. Thus, if vision deteriorates, rapid action must be
taken to prevent irreversible damage, including imme-
diate surgery to decompress the orbit and allow air to
escape. An urgent CT scan should be requested to local-
ize the air. Surgical options include lateral canthotomy,
cantholysis, and direct aspiration of the air. Addition-
ally, intravenous steroids to reduce intraorbital infl am-
mation and acetazolamide or mannitol to reduce
intraorbital pressure have been suggested; however, no
randomized controlled trials have investigated the effi -
cacy of these treatments in this condition.3
In ESS, in which there is the possibility of violation
of the lamina papyracea, patients are counseled to not
blow their nose and to open their mouth if they must
sneeze for at least 3 or 4 days postoperatively.
Figure 19-4. Coronal sinus computed tomography scan demon-
strating bony dehiscence over the optic nerve in the sphenoid sinus
on the left (small arrow) and a dehiscent optic nerve in the Onodi
cell on the right (large arrow). The right superior cell is a posterior
ethmoid cell or an Onodi cell because it overrides the sphenoid cell
below it.
Figure 19-5. Sinus computed tomography scan 3 days after endo-
scopic sinus surgery demonstrating a left orbital abscess with propto-
sis and stretching of the left optic nerve.
Figure 19-6. The patient in Figure 19-5 is shown the following day
after drainage of the abscess and decompression. Note the persistent
profound proptosis and edema.

142
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
References
1. Hackman TG, Ferguson BJ: Powered instrumentation and tissue
effects in the nose and paranasal sinuses. Curr Opin Otolaryngol
Head Neck Surg 13:22-26, 2005.
2. Goodall KL, Brahma A, Bates A, Leatherbarrow B: Lateral can-
thotomy and inferior cantholysis: An effective method of urgent
orbital decompression for sight threatening acute retrobulbar
haemorrhage. Injury 30:485-490, 1999.
3. Rubinstein A, Riddell CE, Akram I, et al: Orbital emphysema
leading to blindness following routine functional endoscopic sinus
surgery. Arch Ophthalmol 123:1452, 2005.
Figure 19-7. Sinus computed tomography scan demonstrating
orbital and facial emphysema 6 hours after left endoscopic sinus
surgery in which the lamina papyracea was disrupted. Note the air in
both orbits and below the maxillary sinus. The patient blew her nose
and continued to press the eye after the onset of eye swelling. This
led to increased orbital and facial emphysema.
A
B
Figure 19-8. A, Eyes almost completely shut by orbital and facial
emphysema. B, Ten days after the onset of emphysema the swelling
has largely resolved without intervention.
PEARLS
• Orbital complications can frequently be avoided by
palpating or balloting the eye during the procedure
and noting endoscopically whether any movement is
present.
• The rare complication of subcutaneous orbital
emphysema after ESS can be minimized by
instructing patients to not blow their nose and to
avoid sneezing with the mouth closed for the fi rst
several days postoperatively, particularly if the
lamina papyracea has been violated.
• Loss of the ability to see the color red is an early
indicator of visual loss.
• A lateral canthotomy with cantholysis is the fastest
and easiest method to decompress the orbit.
• Lateral canthotomy does not necessarily require
subsequent surgical closure.
PITFALLS
• Canthotomy alone, without cantholysis, will not
adequately decompress the orbit.
• Delay of orbital decompression in the event of
retrobulbar hemorrhage to obtain an ophthalmology
consultation may result in blindness.
• Microdébriders can quickly cause irreparable
damage to the medial rectus and should not be
used adjacent to the lamina papyracea by
inexperienced surgeons if vision is obscured with
bleeding or if a bony dehiscence is present.
• Ballottement of the globe in the face of a dehiscent
lamina papyracea and periorbita may increase
subcutaneous emphysema by creating a ball-valve
effect that pumps additional air into the
subcutaneous tissue.

Chapter 20
Bleeding during Endoscopic Sinus Surgery
Carl H. Snyderman and Ricardo L. Carrau
Bleeding during endoscopic sinus surgery is generally
minor and rarely precludes completion of the opera-
tion. Bleeding from the mucosa is increased in the
presence of infl ammation and in revision cases. This
bleeding is usually effectively controlled with removal
of the diseased tissue, selective electrocautery, applica-
tion of hemostatic material, and hot-water irrigation.1-4
The use of powered instrumentation (microdébrider)
facilitates visualization when bleeding from the mucosa
is excessive. Abnormal bleeding may also refl ect an
underlying coagulopathy, most commonly the effect of
antiplatelet medications.
Injury to vessels that supply the mucosa of the nasal
cavity can result in signifi cant blood loss but is generally
readily controlled with electrocautery or ligature (place-
ment of hemoclips) of the vessel. Transection of the
anterior ethmoid artery can result in retraction of the
end of the vessel into the orbit with resultant orbital
hematoma (see Chapter 19). Injury to the posterior
nasal branch of the internal maxillary artery occurs
frequently when sphenoidotomy is performed but is
readily controlled with electrocautery. Rarely, delayed
bleeding from this vessel may occur as long as several
weeks after surgery.
The most dreaded complication of sinus surgery is
injury to the internal carotid artery (ICA). Potential risk
factors include abnormal or distorted anatomy, poor
visualization, greater extent of surgery, and limited
experience of the surgeon. There is a signifi cant risk of
permanent neurologic morbidity and death from an
unanticipated injury to the ICA. Vascular injury can be
avoided with a thorough knowledge of sinus anatomy
and good surgical technique. The use of intraoperative
navigation (image guidance) may also decrease the risk
of inadvertent injury, especially in more complex sinus
surgery.
An endoscopic sinus surgeon should be skilled in
various hemostatic techniques and be prepared to deal
with vascular emergencies, including injury to the
ICA.
ANATOMY
The nasal cavity and paranasal sinuses have a rich blood
supply derived from branches of the external and inter-
nal carotid arteries. Terminal branches of the external
carotid artery include the sphenopalatine, posterior
nasal, and superior labial arteries. The superior labial
artery supplies the anterior nasal septum and anastomo-
ses with other arterial branches at Kiesselbach’s plexus
(Little’s area). The sphenopalatine and posterior nasal
arteries are terminal branches of the internal maxillary
artery and exit the sphenopalatine foramen at the pos-
terior attachment of the middle turbinate (Fig. 20-1).
The sphenopalatine foramen is situated at the posterior
superior corner of the maxillary sinus. In many cases
the sphenopalatine and posterior nasal arteries branch
proximal to the sphenopalatine foramen and exit
through separate foramina.5 The sphenopalatine artery
sends branches along the turbinates of the lateral nasal
wall, and the posterior nasal artery crosses the anterior
surface of the sphenoid sinus at its inferior margin to
supply the posterior nasal septum. Terminal branches
of the ICA include the anterior and posterior ethmoid
arteries. The anterior ethmoid artery crosses the roof
of the nasal cavity posterior to the nasofrontal recess
and is located in a coronal plane that is tangential to
the posterior surface of the globe (Fig. 20-2). The posi-
tion of the posterior ethmoid artery is more variable,
but it is usually found crossing the roof of the ethmoid
anterior to the sphenoid sinus approximately 4 to 7 mm
anterior to the optic nerve canal.
143

144
Section 1
Nasal Cavity, Nasopharynx, and Sinuses
The course of the ICA is usually apparent in a well-
pneumatized sphenoid sinus. When lateral septations
are present, they invariably lead to the ICA, which may
be dehiscent in a small percentage of cases (Fig. 20-3).
The petrous portion of the ICA turns vertically at the
second genu to form the paraclival ICA and is in line
with the medial pterygoid plate. The vidian artery and
the pterygoid canal are useful landmarks for locating
the second genu of the ICA when removal of pterygoid
bone is necessary (Fig. 20-4). The vertical segment of
the ICA continues into the cavernous segment, where
it courses lateral to the optic nerve. The lateral optic-
carotid recess separates these structures and represents
pneumatization of the anterior clinoid (Fig. 20-5). The
medial optic-carotid recess is less apparent but is of
greater signifi cance because the ICA deviates medially
here before it courses behind the optic nerve and is at
greater risk of injury.
Lateral posterior
nasal arteries
Posterior septal
branches
Sphenopalatine
artery
Artery of
pterygoid canal
Descending
palatine artery
Lesser palatine
artery
Greater palatine artery
Figure 20-1. The sphenopalatine and posterior nasal arteries exit
the sphenopalatine foramen at the posterior attachment of the
middle turbinate. (Reprinted with permission from Snyderman CH, Carrau
RL: Endoscopic ligation of the sphenopalatine artery for epistaxis. Op Tech
Otolaryngol Head Neck Surg 8:85-89, 1997.)
Figure 20-2. Coronal computed tomography scan after endoscopic
skull base surgery with ligation of the anterior ethmoid arteries (metal
hemoclips, arrows).
ICA
Figure 20-3. Endoscopic sphenoidotomy with a left lateral septa-
tion deviating toward the left internal carotid artery (ICA).
Figure 20-4. The vidian artery and pterygoid canal (arrow) are
important landmarks for locating the second genu of the internal
carotid artery.

Chapter 20
Bleeding during Endoscopic Sinus Surgery
145
PATIENT SELECTION
Indications for endoscopic sinus surgery include infl am-
matory and neoplastic conditions. Acute infectious
problems include sinusitis associated with severe pain,
sinusitis in an immunocompromised host, or sinusitis
associated with an orbital or intracranial abscess. The
goal of surgery performed for nasal polyposis is to pri-
marily improve the airway, but it may also relieve sinus
obstruction and have a secondary benefi t on pulmonary
function in patients with asthma. In patients with
chronic sinusitis, surgery is designed to relieve irrevers-
ible sinus obstruction. Other non-neoplastic conditions
include expansile mucoceles and approaches for orbital
(Grave’s exophthalmos, optic nerve decompression
after trauma) and skull base (meningocele, cerebrospi-
nal fl uid [CSF] leak) conditions. Neoplastic conditions
include both benign and malignant neoplasms of the
sinonasal cavity and cranial base.
Before surgery, patients should be screened for a
history of a bleeding diathesis, and all medications with
antiplatelet properties should be stopped at least 1
week before surgery if possible. Depending on the
underlying condition, patients taking warfarin (Couma-
din) may need to have their medication switched to
intravenous heparin before surgery.
Patients who have undergone any type of surgery
should be questioned about bleeding as a complication
of surgery. In the presence of a positive history of opera-
tive bleeding, previous operative reports should be
reviewed for details regarding the extent of surgery and
bleeding problems encountered.
PREOPERATIVE EVALUATION
Imaging studies should be reviewed before surgery to
assess the extent of disease, gather evidence of previous
surgery, and look for anatomic variations. Anatomic
landmarks to identify on computed tomography include
the level of the cribriform plate relative to the roof
of the ethmoid sinus, the degree of pneumatization
of the sphenoid sinus, lateral sphenoid septations,
and a dehiscent or aberrant ICA. Rarely, the carotid
canal may be dehiscent from a previous surgical
misadventure.
If the ICA is at signifi cant risk for injury during
surgery because of the extent of the pathology and the
planned procedure, collateral intracranial circulation
can be assessed preoperatively with a balloon occlusion
test. This test will provide useful information regarding
the risk for a major neurologic event if the artery needs
to be sacrifi ced. Such information may alter the surgical
plan.
PREOPERATIVE PLANNING
Routine hematologic tests of coagulation and platelet
function are not necessary in patients without a per-
sonal or family history suggestive of a coagulopathy. In
patients with a history of signifi cant bleeding at the time
of previous endoscopic sinus surgery, angiography of
the ICA may be indicated to rule out a pseudoaneurysm
(Fig. 20-6). The time interval since previous surgery is
not relevant because delayed rupture of a pseudoaneu-
rysm of the ICA can occur as long as several years after
the injury.
If injury to the ICA during surgery is anticipated,6
a femoral sheath can be placed at the time of the
balloon occlusion test and left in place during surgery.
If a vascular injury occurs, a balloon catheter can be
fl oated up to the site of injury under fl uoroscopy and
ON
ICA
Figure 20-5. Endoscopic view (cadaveric dissection) of the right
lateral optic-carotid recess with a prominent optic nerve (ON) and
internal carotid artery (ICA) canal. Note how the internal carotid
canal turns medially at its junction with the optic nerve (arrow).
Figure 20-6. A computed tomographic angiogram of a patient
referred after endoscopic sinus surgery complicated by profuse hem-
orrhage demonstrates a pseudoaneurysm of the internal carotid
artery (arrow).