Operative Technique in Plastic Surgery – Kevin C.Chung

■ Skull defects posterior to the hairline may be palpable on exam, though not
visually detectable.
■ Bulging of soft tissue over a skull defect may be an indication of increased
intracranial pressure. This is a particularly important finding in the setting of
multisuture cranial synostosis with residual skull defects following prior
cranioplasty and indicates the need for cranial vault expansion in addition to
reconstruction of the skull defect.
■ The soft tissue in the region of the bony defect should be evaluated.
Evaluation should include assessment of prior surgical scars and evidence of
previous radiation injury to the skin.
■ The volume and contour of the soft tissue envelope over the calvarial defect
should be evaluated. This is particularly important if the calvarial vault will
undergo significant expansion with bony reconstruction. Expansion may result
in inadequate soft tissue coverage over the bone grafts.1
IMAGING
■ A CT scan of the head and maxillofacial skeleton with fine cuts should be
obtained for preoperative planning purposes.
■ 3D reconstructions of the calvarium are used to visualize the defect and plan
for reconstruction (FIG 1).
SURGICAL MANAGEMENT
■ The goals of calvarial vault reconstruction are to provide adequate protection
for intracranial structures and to re-establish an aesthetic cranial contour.
Preoperative Planning
■ Preoperative CT scan with 3D reconstruction images should be reviewed.1–3
■ Location and size of the bony defect should be assessed.
■ An appropriate calvarial donor site should be identified. Adequacy is
determined by the presence of sufficient bicortical calvarial bone.
■ If inadequate calvarial bone is available, iliac crest or split rib grafts should be
considered.
Positioning
■ The patient is placed in a supine or prone position, depending on location of
the calvarial defect. A gel-padded Mayfield head rest (horseshoe) is positioned
based on the location of the defect and bone graft donor site.

■ If the patient is positioned prone, careful padding is required to avoid
pressure on the globes.
■ If a posterior calvarial donor site is planned for anterior bone grafting, the
patient may require closure of the donor site and repositioning for access to the
anterior calvarium.
Approach
■ Surgical approach to the calvarial vault is typically performed via a bicoronal
incision, which provides adequate access to the skull defect as well as to
potential bone graft donor sites.
■ A bicoronal incision can be modified based on prior surgical scars or if a
noncalvarial donor site is planned.
■ Transection of prior scars should be avoided because it compromises blood
flow to the scalp.
■ Iliac donor sites can be approached through either an anterior or a posterior
approach.1
■ Split rib grafts are approached via a limited thoracotomy incision.4
FIG 1 • Preoperative 3D CT scans of a patient with
Saethre-Chotzen. A. The AP view demonstrates a right
forehead skull defect and a left orbital rim defect. B.
Right lateral view demonstrates the right lateral
forehead defect. The parietal skull demonstrated

adequate thickness for split calvarial bone graft harvest.
T E C H N I Q U E S
■ Preparation of the Skull Defect Site
■ If no scalp scars are present, a zigzag bicoronal incision is marked.
■ If a pre-existing bicoronal scar is present, it is used as the incision (TECH
FIG 1).
■ A 1-cm-wide area of hair is trimmed on either side of the proposed incision.
■ The hair is parted and secured with rubber bands.
■ Along the incision line, the scalp is injected with 0.25% Marcaine with
epinephrine, (1 cc/kg). If an infant is undergoing the procedure, the local
anesthesia can be diluted with normal saline at a 1:1 ratio to increase the total
volume injected.
■ Bicoronal incision is made with Colorado tip Bovie cautery or scalpel.5
Scalp flaps are elevated in the subgaleal plane. In the region of the bony
defect, avoid injuring the dura.
■ In the region of planned osteotomies, including regions of split calvarial
bone graft harvest, dissection is performed in the subperiosteal plane.
■ With neurosurgery assistance, the soft tissues and dura are dissected away
from the bony defect, and bone edges are debrided as necessary prior to
harvesting bone graft material.

TECH FIG 1 • A prior zigzag bicoronal incision was
used to access the calvarial vault. Note that this
patient required hardware removal in addition to bone
grafting to correct areas of bone reabsorption.
■ Split Calvarial Bone Graft
■ The author prefers harvesting a full-thickness calvarial bone graft from the
parietal calvarium with the assistance of neurosurgery (TECH FIG 2A).1,3
■ Once the full-thickness bone graft is harvested, it is split on the back table
with the use of a reciprocating saw and a thin osteotome.
■ The author prefers using the reciprocating saw along the borders of the full-
thickness bone graft; the subsequent cleavage of the inner and outer tables is
accomplished with the osteotome.1,3
■ If a large bone graft is harvested, it can be divided into smaller strips to
facilitate separation of the inner and outer tables.
■ The outer table is fixated at the donor site with plates and screws (TECH
FIG 2B,C).
■ In the pediatric population, fixation is performed with resorbable plates and
screws.6 In skeletally mature patients, either resorbable or titanium plates

and screws can be used to provide fixation.
■ The inner table bone graft is then used to cover the calvarial defect and
secured similarly.
■ The scalp is reapproximated with transgaleal interrupted Vicryl sutures.
(Typically, the author uses 3-0 and 4-0 Vicryl for pediatric patients and 2-0
and 3-0 Vicryl for adults.) The skin is reapproximated with a 5-0 Monocryl
running baseball stitch or staples.
■ The hair is washed with sterile saline and shampoo.
■ The incision is dressed with bacitracin ointment followed by Xeroform
sterile cotton fluffs, a sterile blue towel folded as a turban, and covered with
burn stretch netting for gentle compression.

TECH FIG 2 • A. The inner (left) and outer (right)
tables of split parietal calvarium were used to
reconstruct the anterior calvarium. B. AP view CT
scan demonstrating the reconstructed forehead
following bifrontal craniotomy with rotation and
readvancement of the left forehead with split calvarial
bone grafting. C. Bird’s eye view CT scan
demonstrating the right parietal split calvarial bone
graft donor sites and recipient sites in the left temple
and orbital rim.

■ Iliac Crest Bone Graft
■ The skin immediately lateral to the anterior superior iliac crest is retracted
medially.
■ A skin incision is then made over the iliac crest, with dissection through the
subcutaneous tissue until the external oblique muscle fascia is encountered.
The external oblique insertion is elevated in the subperiosteal plane from the
iliac crest.
■ On the internal iliac fossa, the iliacus muscle is elevated in the region of the
planned bone graft harvest.
■ Osteotomies are made with a reciprocating saw through a single cortex of
the iliac bone. A right-angle reciprocating saw is used to cut the posterior
aspect of the bone graft (TECH FIG 3).1
■ An osteotome is used to separate the medial cortex from the cancellous
portion of the iliac bone.
■ Thrombin-soaked Gelfoam is placed over the exposed cancellous bone. The
iliacus muscle is resuspended over the iliac crest to the external oblique and
tensor fascia lata.
■ The subcutaneous tissue and skin is closed with resorbable sutures and the
incision covered with Dermabond.
TECH FIG 3 • Harvest of iliac crest bone graft from
iliac fossa via an anterior approach. Bone is harvested
from the inner table with a variable amount of

cancellous bone.
■ Rib Graft
■ The patient is placed in the supine position for smaller sized rib grafts. For
larger grafts, the patient is placed in the lateral thoracotomy position.4
■ The incision is planned at the level of the inframammary fold and extended
posteriorly based upon the size of the graft.
■ The incision is extended to the sixth rib. The periosteum is incised
longitudinally and the rib bluntly dissected circumferentially from the
periosteum. A rib periosteal stripper is used to release the posterior rib
periosteum, without violation of the pleural space (TECH FIG 4).
■ Avoid injury to the subcostal neurovascular bundle.
■ At the posterolateral aspect of the graft, the rib is divided with rib cutters.
■ The rib is then elevated from lateral to medial ensuring that the pleura
remains intact. Anteriorly, the rib is also divided with a rib cutter.
■ The pleural lining is inspected for pleural tears. The dissection pocket is
filled with sterile saline, and a Valsalva maneuver is performed to determine
whether an air leak is present. If an air leak is noted, the pleura is repaired
over a red rubber catheter. The catheter is removed at final wound closure
during a Valsalva maneuver provided by the anesthesiologist. If no air leak is
present, then the periosteum is reapproximated with 2-0 Vicryl suture, and
the remaining wound is closed.
■ If an additional rib is required, the fourth rib is harvested through the same
incision in a similar manner. The fourth rib is harvested lateral and posterior
to the breast.
■ The soft tissues are then reapproximated with layered wound closure.

TECH FIG 4 • A. Rib graft harvest generally targets
the sixth rib. B. A rib periosteal stripper is used to
separate the posterior periosteum from the rib. The
periosteum is repaired after removal of the rib.
PEARLS AND PITFALLS
CSF leak
■ Dural tears need to be identified at the time of closure and
repaired.
■ Failure to recognize a CSF leak may lead to significant wound
healing problems and necessitate return to the operating room.
Operative
planning
■ Careful preoperative planning is required to determine the size of
required bone graft and donor-site availability.
Pneumothorax
■ Postoperative chest x-rays are required if the pleural space is
violated and repaired.
■ Failure to treat an air leak following rib harvest can result in a
postoperative tension pneumothorax.
Adjacent rib
harvest
■ Failure to harvest every other rib can result in paradoxical chest
wall movement with inhalation.
■ Leave an intact rib between harvested ribs (ie, fourth and sixth
ribs with fifth rib intact).

POSTOPERATIVE CARE
■ Perioperative systemic antibiotics are discontinued after 23 hours.
■ The dressing is removed on postoperative day 2.
■ Antibiotic ointment is continued on the incision for 1 week.
■ The patient is allowed to shower on postoperative day 2.
■ No swimming or contact sports for 4 weeks following surgery.
OUTCOMES
■ The majority of patients undergoing reconstruction for calvarial defects with
autologous bone reconstruction have satisfactory functional and aesthetic
outcomes.
■ Sahoo et al. demonstrated fewer complications with autologous reconstruction
compared to all plastic materials.3
COMPLICATIONS
■ Recipient site complications:7
■ Bone infection
■ Bone resorption8
■ Contour deformities
■ Recurrent skull defects
■ Prominence or exposure of titanium hardware
■ Donor site complications:7
■ Seroma
■ Hematoma
■ Pneumothorax (rib)
■ Contour deformities
■ Paresthesias secondary to nerve injury
■ Gait disturbances
■ Fracture
■ Hernia
■ Injury to internal organs
REFERENCES
1. Artico M, Ferrante L, Pastore FS, et al. Bone autografting of the calvaria and
craniofacial skeleton: historical background, surgical results in a series of 15
patients, and review of the literature. Surg Neurol. 2003;60(1):71-79.
2. Zouhary KJ, Bone Graft harvesting from distant sites: concepts and

techniques. Oral Maxillofac Surg Clin North Am. 2010;22(3):301-316.
3. Sahoo N, Roy ID, Desai AP, Gupta V. Comparative evaluation of autogenous
calvarial bone graft and alloplastic materials for secondary reconstruction of
cranial defects. J Craniofac Surg. 2010;21: 79-82.
4. Sahoo NK, Roy ID, Rangarajan H. Cranioplasty in children with split rib
graft. Med J Armed Forces India. 2011;67(1): 83-85.
5. Wood JS, Kittinger BJ, Perry VL, et al. Craniosynostosis incision: scalpel or
cautery? J Craniofac Surg. 2014;25(4):1256-1259.
6. Fearon JA. Observations on the use of rigid fixation for craniofacial
deformities in infants and young children. Plast Reconstr Surg.
1995;95(4):634-637.
7. Tessier P, Kawamoto H, Posnick J, et al. Complications of harvesting
autogenous bone grafts: a group experience of 20,000 cases. Plast Reconstr
Surg. 2005;116(5 Suppl):72S-73S.
8. Schuss P1, Vatter H, Oszvald A, et al. Bone flap resorption: risk factors for the
development of a long-term complication following cranioplasty after
decompressive craniectomy. J Neurotrauma. 2013;30(2):91-95.

48
CHAPTER
Section VI: Frontal Sinus
Frontal Sinus Cranialization
Mohamad Masoumy, Prasanth Patcha, Robert C. Dinsmore,
and Jack C. Yu
DEFINITION
■ Cranialization refers to the removal of the posterior table of the frontal sinus
with occlusion of the inlet into the frontonasal ducts and allowing the neural
structures, mainly frontal lobes of the brain and the intact dura, to move
directly posterior to the anterior table of the frontal bone.
■ Cranialization is performed in patients with frontal sinus fractures when the
frontonasal duct drainage is interrupted and cannot be reconstituted even with
intubation or endoscopic salvage procedures.1–4
■ Once frontonasal duct integrity is lost, the two surgical options are
cranialization and obturation. Obturation is defined as filling of the frontal
sinus with grafts, often consisting of adipose tissue. Both cranialization and
obturation require the complete removal of sinus mucosa and closure of the
cephalic part of the frontonasal duct with two key differences.
■ In obturation, the posterior table must be preserved or restored. If there is any
concern for CSF leak, remove the posterior table and inspect the dura for
injury. During cranialization, the posterior table must be resected.

FIG 1 • A. Frontal sinuses in situ. B. Parasagittal
section, normal anatomy. C. Supraorbital foramina
(arrows) mark the lateral boundaries of the frontal sinus.
The anterior table has been partially removed from the
left half of the frontal sinus on this model. D. Anterior
table of frontal sinus reflected.
■ In obturation, bone, fat and other tissue are used to fill the frontal sinus space.
In cranialization, this space is ultimately occupied by the brain and allows for
brain edema without increased intracranial pressure; as the brain moves into
this space, the anterior table of the frontal bone becomes the only bony layer

of the inferior anterior cranial vault.3
ANATOMY
■ The frontal sinus is located in the lower 10% to 15% of the forehead and the
width ranges from 2 cm to more than 10 cm. The supraorbital foramen can
serve as an approximate indicator of the lateral extent of the frontal sinus. AP
dimensions measure approximately 15 mm at the base with a gradual taper
cephalically, extending 20 to 30 mm with a variable, scalloped border. Often a
complete bony septum separates the sinus cavity into left and right
compartments (FIG 1).
■ Mucus-secreting respiratory mucosa completely lines the internal surface of
the frontal sinus. The mucous drains through a funnel-shaped outlet leading
into the frontonasal duct, which opens in the infundibulum of the middle
meatus of the nose.
■ Behind the posterior table is the triangular bony anchor of the falx cerebri,
crista galli, bordered laterally by the cribriform plate of the ethmoid bone. The
olfactory fibers exit the cranium into the most cephalic part of the nasal cavity
to provide special visceral afferent innervations. Dural sleeves cover these
olfactory fibers. In trauma, the laceration of these dural sleeves by bone
fragments leads to CSF rhinorrhea.
■ The anterior cranial fossa directly above the nasal cavity is and must remain
completely sterile. Thus, the surgeon’s primary objective in caring for patients
with frontal sinus fractures is to restore this secure separation of the nose from
the intracranial space to avoid infection from nasopharyngeal flora.
PATHOGENESIS
■ During sudden compressive loading of the forehead, as in a blunt frontal
impact, the anterior table will deform rapidly. If the strain exceeds the ultimate
tensile strain of the bone, it fractures. Fracturing absorbs kinetic energy and
greatly reduces force transmission, protecting the frontal lobe of the brain.
■ Higher energy impacts can extend fractures across the apex and the floor of
the sinus into the posterior table and the frontonasal duct.2
■ Frontal sinus trauma resulting in severe and extensive fractures of the anterior
and posterior tables frequently involves the frontonasal outflow tract.
■ If there is greater than 25% disruption of the posterior table, cranialization
should be considered.5
■ Another indication for cranialization is for closure after anterior skull base

tumor surgeries or other craniotomy procedures involving the anterior vault.
NATURAL HISTORY
■ Significant frontal sinus injuries involving the posterior table or frontonasal
duct can lead to the complications of mucocele, mucopyocele, osteomyelitis,
late CSF leak, meningitis, and cerebral abscess. Management via cranialization
during the initial fracture can help to avoid these sequelae.1–8
PATIENT HISTORY AND PHYSICAL FINDINGS
■ Blunt and penetrating traumas are often the cause of frontal sinus fractures.
The patient may have a history of recent or remote trauma (FIG 2). In the
setting of remote trauma, a high level of suspicion must be maintained for such
sequelae as mucocele/mucopyocele, CSF leak (early or late), and osteomyelitis
of the frontal bone.
■ At the time of evaluation, assess contour abnormalities of the forehead, brow,
and frontonasal region. Document presenting symptoms such as paresthesia,
numbness, or paralysis. Furthermore, search for associated injuries of other
facial regions, the cervical spine, brain, eyes, cranial nerves, and the major
neck vessels. Advance Trauma Life Support protocols should always be
followed.
■ The initial note should document the patient’s neurological status, olfaction,
visual acuity, extraocular movements, pupil size and reactivity, rhinorrhea if
present, maxillary and mandibular stability, occlusion, facial movements, and
sensation. Cervical tenderness is important, especially if it is out of proportion
to radiological or clinical findings. Lateral neck pain could represent
carotidynia, a sign of carotid artery injury.
IMAGING
■ CT imaging with thin-cut axial, coronal, sagittal with 3D reconstructions is the
radiologic gold standard. These images evaluate both anterior and posterior
table frontal sinus fractures as well as associated intracranial, facial, and spinal
injuries (FIG 3).
■ Some surgeons advocate intraoperative navigation using available CT data
with a stable fiduciary and infrared multicamera system. The advances in
stealth technology have rendered such guidance tools easier to use as well as
simpler and faster to set up.
■ 6-foot Caldwell x-ray with a coin reference is more of a historical relic to help

map the boundaries of the frontal sinus.3–5
FIG 2 • Massive craniofacial wound from shotgun blast
at close range.
FIG 3 • A. 3D CT reconstruction demonstrating
comminuted facial fractures with concomitant frontal
sinus injury from the shotgun blast. B. Axial CT
demonstrating massive injuries to the anterior and
posterior tables of the frontal sinus with segmental bone
loss. C. Axial CT image showing destruction of the
frontonasal duct.
DIFFERENTIAL DIAGNOSIS
■ Frontal sinus fractures need to be further characterized using the following
variables to best guide treatment:
■ Extent of injury to the anterior and posterior tables including severity of
displacement and comminution
■ The status of the frontonasal duct

■ Dura integrity
■ Status of the brain (see FIG 3B,C).3,4,6,7
NONOPERATIVE MANAGEMENT
■ Advise all patients to avoid pressurization of the nasal cavity and the paranasal
sinuses. Instruct patients to sneeze through an open mouth and refrain from
nose blowing to help prevent pressurization.
■ Nonoperative management is not applicable for injuries that disrupt drainage
from the frontal sinus via the frontonasal ducts, as inadequate drainage will
inevitably result in mucocele formation and eventual infection.
■ Posterior table fractures that are minimally or nondisplaced with intact
frontonasal tract can be treated with simple ORIF of the anterior table if it is
displaced. If the anterior table is not displaced, treatment with close
observation is appropriate. If complications with frontal sinus drainage
develop, salvage/drainage procedures can be performed endoscopically.3,4,6,7
SURGICAL MANAGEMENT
■ Main goals for cranialization
■ Removal of the posterior table
■ Repair of any dural lacerations
■ Removal of all sinus mucosa
■ Plugging the frontonasal outflow tract to create a secure barrier between the
nasopharynx and the anterior cranial fossa
■ Correction of the frontal contour deformity1–8
Preoperative Planning
■ Obtain the necessary consults (neurosurgery, otolaryngology).
■ Review risks (including acute and long-term complications), benefits, and
expectations with patients on the day of surgery.
■ Ensure coordination with the neurosurgical team and proper instrument
availability for osteotomy and fixation techniques.
Positioning
■ The patient is positioned supine with oral intubation and the table rotated 180
degrees.
■ The patient’s body can be tilted upward (30 to 40 degrees) and the neck
retroflexed 15 to 20 degrees (when clinically feasible).

■ The surgical preparation and draping should include the head and right lateral
thigh for possible fat graft harvest.
Approach
■ A coronal incision is used with various modifications taking into consideration
hair pattern and density and exposure needs.
T E C H N I Q U E S
■ Preparation and Exposure
■ The hairline in the forehead with lateral extension down to the preauricular
areas is marked before shaving the hair back 1 to 2 cm.
■ A standard coronal incision can be used for individuals with receding
hairlines or baldness.
■ Inject the planned incision site with 0.25% bupivacaine with 1:200 000
epinephrine.
■ The entire face and the scalp are prepped and draped.
■ Prep the abdomen if subcutaneous fat is to be used as graft.
■ Other potential donor sites are the right anterosuperior iliac crest with
extension to lateral thigh or the right hemithorax if cortical-cancellous bone
and fascial grafts are needed (TECH FIG 1A).
■ The planned coronal incision is made sharply or with fine needle tip
electrocautery to reduce bleeding.
■ To ensure sufficient length for the pericranial flap, the scalp can be
dissected posteriorly in the subcutaneous plane for a significant length (6 to
8 cm or more if needed) before cutting through the galea while preserving
the pericranium (TECH FIG 1B).
■ The anterior dissection then proceeds within this relatively avascular
subgaleal, supraperiosteal plane until the superior orbital rims.
■ The pericranial flap of the desired width and length is then marked, incised,
and raised, from posterior toward the orbits.
■ Elevate the pericranial flap by incising the periosteum at the superior
orbital rims. During this elevation, the supraorbital and supratrochlear
neurovascular bundles located at the medial third of the superior orbital rim

must be carefully preserved as they provide the blood supply to the
pericranial flap (TECH FIG 1C).
■ If complete mobilization of the superior orbital nerve is needed, a 2-mm
osteotome can be used to convert the foramen to a notch by cutting the
most caudal part of the foramen medial and lateral to the neurovascular
bundle.
The neurosurgery team then performs frontal craniotomy to provide
access to the anterior cranial fossa; the frontal bone flap is a
potential source of split-thickness cranial bone grafts (TECH FIG
1D).4
TECH FIG 1 • A. Planned incision for optimal
exposure. B. Extent of planned pericranial flap that is
anteriorly based. C. Coronal exposure to access
frontal bone and sinus. Care is taken to avoid traction

injury to the supratrochlear and supraorbital
neurovascular bundles. D. Frontal craniotomy
performed with exposed dura.
■ Repair and Closure
■ If the anterior table is intact, accurate ostomy and identification of the
boundaries of the frontal sinus are paramount.
■ Techniques described include using bayonet forceps, transillumination, and
intraoperative navigation or 5-foot Caldwell x-ray with coin reference.5
■ After outlining the borders of the sinus, 1.5-mm plates are preapplied,
spanning the margins prior to osteotomy allowing for accurate repositioning
of the anterior table.
■ The anterior table is then perforated with a sagittal saw or side-cutting bur;
the hand piece should be angled at 45 degrees toward the sinus and away
from the cranial vault to avoid violation of the posterior table.5
■ There is often extensive fracturing of the anterior table. In these cases, label
the frontal bone fragments before removing them to facilitate their
reassembly and store them in moist gauze.
■ Once the frontal sinus is exposed, the opening to the frontal nasal duct is
inspected and the patency assessed by passing a 10- or 12-French red rubber
tube for a distance of 7 to 10 cm (TECH FIG 2A).
■ If the patency of the duct cannot be ensured, and the posterior table is also
involved, remove the posterior wall and repair lacerations of the dura. This is
usually performed by the neurosurgery team.1,2,4
■ Strip the frontal sinus mucosa completely and supplement by burring the
irregularities on the internal bony surfaces of the frontal sinus (TECH FIG
2B).1,2,4,5
■ A cuff of mucosa at the most cranial end of the frontonasal duct is preserved
and dissected free from the bony canal.
■ A purse-string suture of this mucosal cuff is placed to effectively seal off
the frontal nasal duct. We suggest using 3-0 polyglactin on a small tapered
needle.

TECH FIG 2 • A. With the dura retracted, the extent of
the frontal sinus injury can be assessed. B. An egg-
shaped bur is used to remove the mucosa of the
frontal sinus. C. Split-thickness calvarial bone graft is
used to reconstruct the floor of the anterior cranial
fossa. Drill holes are made to allow fixation with
absorbable 2-0 monofilament sutures. D. The split-
thickness calvarial bone graft is secured in place to

reconstruct the floor of the anterior cranial fossa,
forming a right angle joint posterior to the frontal bar.
E. Split-thickness calvarial bone graft reconstructing
the floor of the anterior cranial fossa after suture
fixation. F. Elevation of pericranial flap from the deep
surface of the coronal flap using a no. 15 scalpel. G.
Elevating the pericranial flap. H. Completion of scalp
closure.
■ Pack particulate cortical-cancellous bone grafts above this closure to further
re-enforce the separation. Any defect of the frontal sinus floor is
reconstructed with split-thickness cranial bone grafts.
■ Two small holes are drilled on the posterior edge of the bone graft with a 3-0
PDS placed through them as a loop. These loops will provide a posterior
anchor to the pericranial flap.
■ The posterior wall of the frontal sinus is completely removed, creating a
smooth continuous floor of the anterior cranial fossa (TECH FIG 2C–E).
■ Introduce the pericranial flap into the intracranial space, lining the floor of
the anterior cranial fossa. Secure the posterior extent of the pericranial flap
with a 3-0 PDS loop on the posterior edge of the bone graft on the floor.
■ A 4 mm horizontal slot is made in the frontal bone to accommodate the
base of the pericranial flap.
■ After insetting the flap, access to the orbital rims or the orbits themselves
will be impossible. It is therefore critically important that all the work in the
orbits and supraorbital rims is complete prior to insetting the pericranial flap
(TECH FIG 2F).
■ Reassemble frontal bone fragments with care taken to remove all the
mucosal tissue. The frontal craniotomy is then repaired using 3-0 PDS,
plates, and screws as needed.
■ Close the deep dermis using 3-0 polyglactin and the scalp with suture or
staples.
■ Drains are used in some cases, with care taken to assure that unimpeded
removal can occur (TECH FIG 2G,H).

PEARLS AND PITFALLS
Physical
findings
■ Search for and document any CSF leak or entrapment of mucosa
within the intracranial space.1,2,4,5
■ Carefully examine for concomitant injuries and identify any
numbness or paresthesia of the forehead indicating possible
supraorbital and supratrochlear nerve injuries.
■ Supraorbital foramen marks the lateral extent of frontal sinus.
Technique
■ Bevel the incision to ensure that it travels parallel to the hair
follicles to avoid alopecia.
■ Once the level of the temporal line is reached, dissection should be
carried deep to the superficial layer of the deep fascia to avoid
transection of the temporal-zygomatic branch of the facial nerve.4
■ Avoid raising the temporal fat pad, which devascularizes the fat
pad leading to temporal wasting.5
■ It is easier to dissect in the suprapericranial plane, leaving the
pericranium on bone and then raising it as a separate layer in a
second step.
■ Remove all mucosa to avoid the formation of a mucocele.
■ Watertight dural repair is of principal importance to help avoid
CSF leaks and ascending infections from sinus spaces.
■ Sufficient space between the frontal bone and supraorbital bar
must be present to allow the pericranial flap to enter the
intracranial space.
Postoperative
■ Have a high index of suspicion to identify complications such as
meningitis, mucocele, or mucopyocele leading to osteomyelitis.
POSTOPERATIVE CARE
■ Immediate postoperative care should include evaluations of the neurological,
visual, and olfactory systems.
■ Patients should avoid nose blowing for at least 4 weeks following frontal sinus
surgery.
■ No aspirin for a week and avoid NSAIDs.
■ Some surgeons may advocate steroid use for severe orbital trauma to help with
postoperative edema; however, this must be balanced with the risk of
complications related to perioperative steroids.

■ Postoperative CT is recommended to assess complex fracture reductions.
■ The scalp can be washed by postoperative day 5.
■ Clinical follow-up should include counseling about signs and symptoms of
complications, and patients should understand that these complications might
occur years after the original trauma.1,6,7
OUTCOMES
■ Overall, cranialization has a very high success rate at preventing complications
in both the short and long term after severe traumatic frontal sinus fractures and
frontonasal duct disruption.
■ One study of 72 patients with frontal sinus fractures reports a 6% mucocele
rate. However, of the 30 patients who were treated with cranialization, none
developed a mucocele.9 This prevention also helps avoid complications of
mucopyocele, meningitis, and osteomyelitis.
■ Overall, long-term studies after frontal sinus fractures are lacking because
patients tend to have poor follow-up unless complications arise. Conservative
observation has also been advocated in specific instances of limited CSF leak
or when endoscopic measures can be used to temporize or relieve frontonasal
obstructions.6,7,10
COMPLICATIONS
■ If all mucosal lining is not removed, the patient is at risk of developing a
mucocele, which may progress to a mucopyocele and frontal bone
osteomyelitis (a condition known as Pott puffy tumor) and subsequent brain
abscess.2,3
■ A CSF leak may occur with unrecognized or incompletely repaired dural
injuries.
■ Manage this injury with packing, bed rest, lumbar drain, endoscopic
endonasal management, and revision surgery.
■ Meningitis

FIG 4 • Intermediate postoperative photo showing the
frontonasal region.
■ Injury to the temporal-zygomatic branch of the facial nerve leading to
ipsilateral forehead paralysis
■ Hollowing of the temporal region secondary to excessive disruption of the
temporal fat pad
■ Widened scar from the coronal incision
■ Chronic/severe frontal pain (FIG 4)
REFERENCES
1. Donath A, Sindwani R. Frontal sinus cranialization using the pericranial flap:
an added layer of protection. Laryngoscope. 2006;116(9): 1585-1588.
2. Ruggiero F, Zender CA. Frontal sinus cranialization. Oper Tech Otolayngol
Head Neck Surg. 2010;21(2):143-146.
3. Echo A, Troy JS, Hollier LH Jr. Frontal sinus fractures. Semin Plast Surg.
2010;24(4):375-382.
4. Strong EB. Frontal sinus fractures. Oper Tech Otolayngol Head Neck Surg.
2008;19(2):151-160.
5. Fusetti S, Hammer B, Kellman R, Matula C, Strong EB. Cranialization.
Cranialization 2016 [cited 2016; Available from:

showPage=redfix&bone=CMF&segment=Cranium&classification=93-
Frontal%20sinus,%20Posterior%20table%20fractures&treatment=&method=Cr
6. Fox PM, et al. Management of frontal sinus fractures: treatment modality
changes at a level I trauma center. J Craniofac Surg. 2014; 25(6):2038-2042.
7. Weathers WM, et al. Frontal sinus fractures: a conservative shift.

Craniomaxillofac Trauma Reconstr. 2013;6(3):155-160.
8. Ameline E, et al. Cranialization of the frontal sinus. Ann Otolaryngol Chir
Cervicofac. 2001;118(6):352-358.
9. Wallis A, Donald PJ. Frontal sinus fractures: a review of 72 cases.
Laryngoscope. 1988;98(6 Pt 1):593-598.
10. Choi M, et al. A 10-year review of frontal sinus fractures: clinical outcomes
of conservative management of posterior table fractures. Plast Reconstr Surg.
2012;130(2):399-406.

49
CHAPTER
Frontal Sinus Obliteration
with Fat
Matthew M. Smith and Alessandro de Alarcon
DEFINITION
■ Obliteration of the frontal sinus is the process of replacing a diseased frontal
sinus that is normally air-filled.
■ The diseased frontal sinus is obliterated with another material, such as fat.
ANATOMY
■ The midface is made up of five paired paranasal sinuses (maxillary, anterior
ethmoid, posterior ethmoid, sphenoid, and frontal)
■ The boundaries of the frontal sinus are as follows:
■ Anterior: Anterior wall of the frontal sinus
■ Posterior: Posterior wall of the frontal sinus and anterior cranial fossa
■ Inferior: Orbit
■ The anterior wall of the frontal sinus is significantly thicker than the posterior
wall.
■ The frontal sinus is the last paranasal sinus to develop and usually begins to
pneumatize around 6 years of age (FIG 1).
■ It is innervated by the supraorbital and supratrochlear nerves, which are
branches of the first branch of the trigeminal nerve (V1).

FIG 1 • Growth of the frontal sinus.
■ The frontal sinus drains into the middle meatus via the hourglass-shaped
frontal sinus outflow tract. The boundaries of the frontal sinus outflow tract are
as follows:
■ Anterior: Nasofrontal bar, agger nasi cell
■ Posterioinferior: Ethmoid bulla
■ Posterosuperior: Anterior cranial fossa
■ Medial: Middle turbinate
■ Lateral: Lamina papyracea
PATHOGENESIS
■ Frontal sinus injury is the primary indication for frontal sinus obliteration.
■ Chronic frontal sinusitis secondary to obstruction of the frontal sinus outflow
tract.
■ Prior frontal sinus surgery with subsequent mucocele formation.

■ Frontal sinus malignancy with subsequent need for obliteration after
resection of tumor.
■ Direct forehead trauma with subsequent frontal sinus wall fractures.
• Isolated anterior frontal sinus wall fractures with displacement and
nondisplaced posterior wall frontal sinus fractures without CSF leak are the
most amenable to frontal sinus obliteration.
• Displacement of the posterior frontal sinus wall and/or CSF leak is more
frequently treated with cranialization of the frontal sinus rather than
obliteration.
PATIENT HISTORY AND PHYSICAL FINDINGS
■ The history for each patient will be directed toward the proposed cause of his
or her frontal sinus problem.
■ For all patients, it is important to obtain history regarding changes in vision,
mechanism of frontal sinus injury (chronic inflammatory, traumatic), nasal
obstruction, persistent clear rhinorrhea, purulent rhinorrhea, fevers, headaches,
swelling of the forehead, changes or lack of smell, prior sinus surgeries, and
symptoms of meningitis.
■ A complete visual examination should be performed, including visual acuity,
visual fields, pupillary reflex, accommodation, and extraocular movements.
■ Anterior rhinoscopy should be used to examine the nasal cavities for any
evidence of trauma, CSF leak (clear rhinorrhea), or malignancy prior to frontal
sinus surgical intervention.
■ Nasal endoscopy is not needed to view the frontal sinus prior to surgery but is
useful if the patient has had prior surgery and allows the frontal sinus outflow
tract to be easily viewed with an angled endoscope (45 or 70 degree).
■ If the patient has symptoms of persistent or intermittent clear rhinorrhea, the
patient should be instructed to sit in a sniffing position for 3 minutes with a
small basin or cup to collect the clear nasal drainage. This fluid can then be
sent for examination of beta-2-transferrin for confirmation of CSF leak.
■ For those patients with a history of traumatic frontal sinus fracture, the
evaluation for potential foreign bodies within the frontal sinus and other
craniofacial fractures should be completed.
IMAGING
■ CT scan of the sinuses is paramount for the bony framework of the frontal
sinuses.

■ Axial, sagittal, and coronal views should all be obtained to fully view the
frontal sinus in different planes (FIG 2A,B).
■ 0.5-mm cuts should be obtained in order to detect small defects in the frontal
sinus.
■ 3D reconstruction of the frontal sinus can be obtained and is helpful, but not
necessary.
■ Historically a 6-foot Caldwell view with an AP x-ray of the head was
obtained. A quarter was placed over the patient’s forehead during the x-ray to
create an image that could then be laid over the patient for an actual size of the
frontal sinus.
■ MRI with contrast should be obtained prior to surgery if violation of the
posterior frontal wall is suspected to ensure there is no evidence of an
encephalocele and to further evaluate the surrounding soft tissues (FIG 2C).
DIFFERENTIAL DIAGNOSIS
■ Chronic frontal sinusitis
■ Pott puffy tumor
■ Frontal sinus mucocele
■ Frontal sinus fracture
■ Encephalocele
■ Frontal sinus malignancy
NONOPERATIVE MANAGEMENT
■ For nondisplaced fractures of the anterior frontal sinus, observation is an
option, but with any type of mucosal disruption, the patient will be at risk for
mucocele or mucopyocele.
■ Endoscopic management of the frontal sinus may also be explored for chronic
frontal sinusitis and is frequently used as first-line treatment.
SURGICAL MANAGEMENT
Preoperative Planning
■ All imaging must be reviewed prior to surgery to obtain a proper road map of
the frontal sinus.
■ Evaluate for presence of anterior and posterior table fractures.
■ Evaluate for possible anterior cranial fossa communication/involvement.
■ If there is any concern for CSF leak, attempts should be made to collect clear

rhinorrhea for beta-2-transferrin examination.
■ If enough fluid cannot be collected for examination, a gross evaluation of the
fluid can be performed by placing a few drops of the drainage on a white
sheet and looking for a “halo sign.”
■ A collection of blood in the middle with a clear ring of surrounding fluid is
indicative of CSF.
■ Preoperative discussion with the patient and family regarding the extensive
nature of the coronal incision should be performed.
■ Antibiotics should be given prior to surgical intervention.
■ Cefazolin, clindamycin, and ampicillin-sulbactam are all appropriate choices.
■ If the patient has a history of MRSA, then vancomycin should be added to
the antibiotic regimen.
Positioning
■ Patients are placed supine on the operating room table.
■ If a neurosurgical team is involved with the operation, then fixation in a
Mayfield retractor will be used with removal of the headboard. Otherwise, the
patient’s head is placed on a foam donut and positioned in a neutral position.
Approach
■ The primary approach to open frontal sinus obliteration is through a coronal
incision.
■ Endoscopic approaches to the frontal sinus (first reported in 2005) are feasible
but should only be considered in chronic frontal sinusitis.1
FIG 2 • A. Coronal CT showing bone window. B.
Sagittal CT showing bone window. C. Sagittal MRI T2
sequence.

T E C H N I Q U E S
■ Open Coronal Approach to Frontal Sinus
Obliteration
Preparation and Exposure
■ The eyes are coated with optical lubricant and then either covered with a
clear dressing or sutured together by performing a tarsorrhaphy with a 5-0 or
6-0 monofilament colored suture (preferably blue or green so as not to blend
in with eyelashes).
■ A small strip of hair is cut with clippers where the planned coronal incision
is to be placed (TECH FIG 1A).
■ A clear plastic drape can be placed over the upper lip to separate the oral
cavity from the surgical field.
■ Stereotactic navigation is then calibrated if used during the case.
■ The face and scalp are prepped with iodine solution and draped with full
view of the anterior scalp, forehead, and upper face (including eyes and
nose).
■ The abdomen is then prepped over the periumbilical area for fat harvest and
draped with blue towels.
■ This area is covered with surgical drapes and marked for the subsequent
abdominal fat harvest. The surgical drapes can be cut with scissors for
access to the already prepped abdomen.
■ A coronal incision is made from temporal line to temporal line, just anterior
to the helical crus.
■ For improved appearance, the incision line is hidden within the hair line
and may be staggered in a saw-toothed fashion.
■ The incision is taken down to the periosteum exposing the frontal bone
completely.
■ Using the stereotactic navigation, the frontal sinus is then outlined for the
proposed bony incisions.
■ The periosteum of the frontal bone is elevated with a Freer elevator over the
planned incision, leaving it pedicled anteroinferiorly over the brow line
(TECH FIG 1B).

TECH FIG 1 • A. Planned sawtooth coronal incision
with hair removed from suture line. B. Purple marker
outlines planned osteoplastic flap. The periosteal flap
has been elevated and is pedicled anteroinferiorly and
is retracted with hook retractors.
■ The frontal osteoplastic bone flap is then created using a reciprocating or
oscillating saw over the previously planned outline of the frontal sinus.
■ A high-speed cutting drill may be used instead but can result in increased
injury to the edges of the bone flap.
■ If there was a previous fracture in the anterior table of the frontal sinus,
then this can serve as one or all of the planned cuts into the frontal sinus.
■ After the circumferential cuts are made, the only piece of bone that should
be left attached is the frontal intersinus septum, which is removed with a
reciprocating saw, an oscillating saw, a drill using a round drill bit, or an
osteotome.
■ The frontal osteoplastic flap is then wrapped in saline-soaked gauze and
placed on the back table for later use.
Obliteration of the Sinus with Fat
■ If an infectious etiology has been identified, cultures are obtained
immediately upon entry to the sinus.

■ The frontal sinus lining mucosa is then completely removed using forceps.
■ A high-speed drill with a diamond bur is then used to smooth the inner edges
of the sinus to remove all microscopic areas of mucosa. This is also used to
smooth any bony spicules or ledges.
■ We recommend using loupe magnification or the assistance of angled
endoscopes to ensure that all of the mucosa is removed and bony edges are
smooth.
■ If there is evidence of a nondisplaced frontal sinus fracture, extreme care is
taken during removal of the mucosal lining of the posterior frontal sinus
wall to prevent displacement of the fracture.
■ Abdominal fat is then harvested for obliteration of the frontal sinus.
■ A no. 15 blade is used to make a periumbilical incision.
■ Blunt dissection with a hemostat is used to elevate the area and expose the
proposed fat graft.
■ Fat is then harvested en bloc for obliteration of the frontal sinus. The total
amount of fat is dependent on the volume of the frontal sinuses to be
obliterated.
■ The incision is then closed in sequential fashion, and dressing is placed
over the abdominal incision.
■ A 1 × 1 cm piece of temporalis muscle is then harvested for obliteration of
the frontal sinus outflow tract.
■ The frontal sinus outflow tracts are then identified and plugged with the
previously harvested temporalis muscle.
■ The previously harvested fat is then used to fill and obliterate the frontal
sinuses.
Plating and Completion
■ The osteoplastic bone flap is replaced and secured with titanium or
absorbable plates. If the frontal bar was removed or required reconstruction,
it is replaced prior to plating the osteoplastic bone flap (TECH FIG 2).
■ The periosteal flap is then laid over the bony flap and sutured to the
surrounding periosteum with 3-0 suture.
■ The wound is irrigated with saline and hemostasis is achieved with
electrocautery.

TECH FIG 2 • Frontal bar is being reconstructed with
an absorbable plating system. After plating the frontal
bar, the osteoplastic bone flap is replaced and
secured.
■ Negative pressure drains are placed to collect blood or serous fluid
collections.
■ The incision is closed in multiple layers, with sutures or staples to close the
skin.
■ Antibiotic ointment is then applied to the incision, and the head is wrapped
in a compressive dressing.
PEARLS AND PITFALLS
Hemostasis
■ Obtain hemostasis prior to closure. Negative pressure drains allow
monitoring of postoperative fluid in this area. We recommend less
than 30 mL of drainage in a 24-hour period and avoidance of any
bending, Valsalva maneuvers, nose blowing, or excessive activity for
2 wk postoperatively.
Technique
■ All mucosa must be removed from the frontal sinus to prevent
subsequent mucocele formation. This can be ensured with drilling

and smoothing of the frontal sinus bone.
POSTOPERATIVE CARE
■ Patients should be placed on postoperative antibiotics for at least 14 days,
usually amoxicillin-clavulanate.
■ If there is concern for meningitis or other complicated infectious etiology, the
type and course of antibiotic should be tailored to the individual patient.
■ For external incisions, antibiotic ointment should be used to coat the area to
promote healing.
■ Compressive head dressings can be removed in 48 to 72 hours.
■ Negative pressure drains are kept in place until the output for each drain is less
than 30 mL of fluid over a 24-hour period.
■ Avoid bending, Valsalva maneuvers, nose blowing, or excessive activity for 2
weeks to prevent bleeding.
■ Patients should be instructed to “open-mouth sneeze” to avoid excessive
nasal airflow pressure.
■ Nasal saline rinses are recommended to prevent nasal crusting if endonasal
surgery was performed.
■ Staples or sutures in the scalp should be removed in approximately 10 days.
■ Postoperative CT and/or MRI should be performed to establish a baseline of
the newly obliterated frontal sinus.
OUTCOMES
■ Greater than 90% success rate of frontal sinus obliteration has been reported.2
COMPLICATIONS
■ Mucoceles or mucopyoceles may occur years later if any mucosa is retained in
the frontal sinuses.
■ Weber et al. performed a long-term follow-up MRI study that detected
mucoceles in almost 10% of patients after frontal sinus injury.3
■ CSF leak is a potential risk with any damage to the posterior frontal sinus wall
and subsequent dural injury during surgery.
■ Meningitis may occur through communication with the anterior cranial fossa if
there is a defect in the posterior frontal sinus wall.
REFERENCES
1. Ung F, Sindwani R, Metson R. Endoscopic frontal sinus obliteration: a new

technique for the treatment of chronic frontal sinusitis. Otolaryngol Head Neck
Surg. 2005;133:551-555.
2. Mendians AE, Marks SC. Outcome of frontal sinus obliteration.
Laryngoscope. 1999;109:1495-1498.
3. Weber R, Draf W, Kratzsch B, et al. Modern concepts of frontal sinus surgery.
Laryngoscope. 2001;111:137-146.

50
CHAPTER
Pericranial Flap Harvest for
Frontal Sinus Obliteration
Mahmoud Hassouba and John A. van Aalst
DEFINITION
■ The pericranial flap is a well-vascularized, versatile cranial periosteal flap that
can be based anteriorly on the supratrochlear and supraorbital arteries or
laterally on the superficial temporal artery.1
■ The pericranial flap is most commonly used for reconstruction of anterior skull
base defects, including obliteration of the drainage system of the front sinus
following frontal sinus fracture.
ANATOMY
■ The scalp consists of five layers: skin, subcutaneous connective tissue, galea
aponeurotica, loose areolar tissue, and the pericranium.
■ The pericranium is the periosteum of the skull bones and is continuous with
the endosteum along the cranial suture lines.
■ The pericranial flap consists of the skull periosteum with the overlying
subgaleal areolar tissue.
■ The blood supply of the anteriorly based pericranial flap is derived from the
deep branches of the supraorbital and supratrochlear arteries, and both are
branches of the ophthalmic artery.
■ The deep branches arise from the supratrochlear and supraorbital artery exiting
at the level of the supraorbital rim.2
■ There is wide variation in the size of these arterial branches depending on the
size of the frontal branch of the superficial temporal artery.2
■ The axial length of these branches ranges between 15 and 60 mm and most
commonly is approximately 40 mm in length.2
■ In the horizontal plane, the anastomosis between the deep branches is not well

developed, and except for the glabellar region, no anastomoses cross the
midline.
PATHOGENESIS
■ The most common indication for sinus obliteration requiring pericranial flap is
a fracture of the posterior wall of the frontal sinus.
■ As with most craniofacial injuries, frontal sinus fractures result from high-
velocity blunt trauma such as motor vehicle accidents.
PATIENT HISTORY AND PHYSICAL FINDINGS
■ Frontal sinus fractures are often associated with other facial injuries that
require a detailed history, including the mechanism of trauma, as well as a
thorough general and craniofacial-centric physical examination.
■ History taking may be complicated due to patient head injury with loss of
consciousness.
■ The main presenting symptoms are forehead swelling with or without skin
lacerations, forehead paresthesia, and forehead and nasal pain.
■ Signs of frontal sinus fractures include forehead tenderness, contour deformity,
crepitus, and cerebrospinal fluid (CSF) rhinorrhea.
■ Displaced fractures without skin lacerations may be masked by the overlying
soft tissue swelling.
■ All lacerations should be examined under aseptic conditions to evaluate the
integrity of both the anterior and posterior tables as well as the dura.
■ The nasal cavity should be examined for the presence of CSF drainage.
IMAGING
■ CT scan of the facial bones with coronal and axial cuts is the standard for
diagnosis of fractures involving the frontal sinus.
■ 3D reconstructions may be helpful in diagnosing associated craniofacial
injuries.
SURGICAL MANAGEMENT
■ Indications for frontal sinus obliteration include fractures of the floor or
posterior wall of the sinus, oncologic or inflammatory lesions of the frontal
sinus such as osteomas or osteomyelitis, vascular lesions such as arteriovenous
malformations, and failure of endoscopic sinus drainage surgery.3
PREOPERATIVE PLANNING

■ Routine preoperative lab results should be reviewed, and any abnormal finding
should be corrected to prepare the patient for surgery.
■ All available imaging should be available and displayed in the operating room.
■ A sterilized radiographic template of the frontal sinus can be prepared from a
Caldwell radiograph.
■ Doppler ultrasound should be available in the operating room for
intraoperative localization of the flap pedicle if distorted anatomy is
anticipated.
Positioning
■ The patient is placed in supine position on the operating room bed.
■ Oral intubation is preferred with the tube placed centrally and inferiorly.
Approach
■ If a forehead laceration already exists, it can be extended into a natural crease.
■ A midforehead incision or a butterfly transglabellar incision may be used.4
■ The coronal incision is the most reliable and aesthetically favorable approach
for exposure of the forehead and facilitates harvest of the pericranial flap.
■ The sex of the patient and location of the anterior hairline should be taken in
consideration when choosing the location of the coronal incision
■ In individuals with posteriorly displaced anterior hairline or patients with male
pattern baldness, the incision can be placed as far posteriorly as the upper
occiput.
T E C H N I Q U E S
■ Anteriorly Based Pericranial Flap
■ The coronal incision is made 2 to 3 cm posterior to the hairline and extends
to the auricular helix on both sides (TECH FIG 1A).
■ The flap is dissected anteriorly in the subperiosteal plane to the level of the
supraorbital rim and may need to be extended to access other fractures of the
craniofacial skeleton (TECH FIG 1B).
■ Marking of the frontal sinus can be performed using the premade template.
■ The frontal sinus is then accessed through a pre-existing anterior table

fracture or by removal of the frontal bone in conjunction with the
neurosurgery team.
■ Mucosal lining of the sinus is completely exenterated using a periosteal
elevator; 0.5 to 1 mm of the osseous lining is then removed using a bur.
■ At the ostia of the nasofrontal ducts, the mucosa is folded on itself.
■ Doppler scanning may be used for accurate localization of the pericranial
flap pedicle and aid in planning the flap.
■ An anteriorly based periosteal flap is dissected from the coronal flap with a
no. 15 blade in the subaponeurotic plane to the supraorbital rim (TECH FIG
1C).
■ The flap is then folded against itself to fill and obliterate the frontal sinus,
acting as a barrier between the brain and remaining sinus (TECH FIG 1D).
■ The anterior table is then rigidly fixated in place leaving a 3- to 5-mm gap
between its inferior border and the frontal bar to prevent compression of the
blood supply to the flap (TECH FIG 1E).
■ A suction drain is then placed in the subgaleal plane, and the coronal flap is
redraped and the incision is closed in layers.

TECH FIG 1 • A. Placement of coronal incision. B.
The coronal incision proceeds through the layers of
the scalp to the subpericranial plane. (These layers
can be remembered using the acronym SCALP.)
Dissection is performed on the skull to the orbital rim
and, as necessary, into the area of the orbits,
exposing the zygomatic arches bilaterally. The
pericranial flap is exposed and separated from the
overlying soft tissue. C. Elevation of the pericranial
flap from the coronal flap. Frontal sinus has been
exposed by removal of anterior table of frontal sinus.
D. Obliteration of the frontal sinus and frontal recess
by folding pericranial flap onto itself and filling the
frontal sinus. This serves as a barrier between the
brain and remnant sinus cavity. E. Before the frontal
bone (asterisk) is replaced, the anterior region of
craniotomy is burred to ensure that the edges are
smooth and do not impinge on the pericranial flap as it
enters the intracranial cavity (arrows). The bone flap is
then secured, and the skin is closed.
■ Laterally Based Pericranial Flap
■ All operative steps are similar to harvest of the anteriorly based flap, with
the exception that the flap is either harvested unilaterally with its base in the

temporal area with blood supply from the superficial temporal artery or
bilaterally depending on the size of the sinus.
■ The base of the flap is located approximately 2 cm from the gap between the
temporoparietal fascia and the galea aponeurotica.
■ The width of the flap base usually varies between 5 and 8 cm depending on
the size of the frontal sinus.
■ A unilateral flap should not extend beyond the midline.
■ The dimensions of the flap may vary but can be up to 10 × 10 cm according
to the tissue amount required to fill the frontal sinus.
PEARLS AND PITFALLS
Coronal
incision
■ Zigzag or curved incision is made to facilitate accurate closure at the
end of the procedure.
Dissection
■ Care should be taken while dissecting the flap medially to avoid
injury to the deep branches of the supratrochlear and supraorbital
artery and laterally to avoid injury to the frontal branch of the facial
nerve.
Dura
■ If the dura is exposed, it should be carefully examined and
fenestrations should be repaired.
Hemostasis
■ Careful hemostasis should be achieved before closure of the coronal
flap to avoid hematoma formation that can lead to flap compression
and necrosis.
POSTOPERATIVE CARE
■ The patient will require monitoring in the ICU because of the high likelihood
of head injury associated with frontal sinus injury.
■ Head of bed elevated to 45 degrees to help venous drainage and avoid soft
tissue swelling.
■ Perioperative antibiotics are indicated because of intracranial extension for 7
to 10 days.
■ Drain remains in place until output is less than 30 mL for 24 hours.
■ Narcotic pain medications are preferred during the first week after the
procedure and are titrated to the patient’s level of pain.

OUTCOMES
■ Successful outcomes of obliteration of the frontal sinus depend on multiple
factors, mainly total removal of mucosal lining and complete obliteration of the
sinus.
■ Aesthetic outcomes of forehead contour after surgery are usually satisfactory.
■ Most published series in the literature report 100% patient satisfaction with the
aesthetic and functional outcomes after frontal sinus obliteration using
pericranial flaps.1,4–7
COMPLICATIONS
■ Early
■ Sinus obliteration using pericranial flaps is associated with low rates of
complication.
■ Seroma formation: Can be avoided by drain placement
■ Active bleeding leading to expanding hematoma requiring flap exploration
• Place a postoperative drain.
• Early recognition of the hematoma and re-exploration.
■ Late
■ Persistent headaches
■ Forehead contour deformities
■ Sinus infection: requires admission, IV antibiotics, and possible surgical
debridement
■ Inadequate mucosal removal leading to mucocele formation; may present
more than a decade after sinus obliteration.1
REFERENCES
1. Parhiscar A, Har-El G. Frontal sinus obliteration with the pericranial flap.
Otolaryngol Head Neck Surg. 2001;24(3):304-307.
2. Potparić Z, Fukuta K, Colen LB, et al. Galeo-pericranial flaps in the forehead:
a study of blood supply and volumes. Br J Plast Surg. 1996;49(8):519-528.
3. Soyka MB, Annen A, Holzmann D. Where endoscopy fails: indications and
experience with the frontal sinus fat obliteration. Rhinology. 2009;47(2):136-
140.
4. Ducic Y, Stone TL. Frontal sinus obliteration using a laterally based pedicled
pericranial flap. Laryngoscope. 1999;109(4):541-545.
5. de Melo WM, Coléte JZ, Mariano RC, et al. Anterior pericranial flap for
frontal sinus duct obliteration: is it a valuable resource? J Craniofac Surg.

2013;24(2):e147-e149.
6. Yano T, Okazaki M, Tanaka K, et al. Feasibility and advantage of a muscle-
sparing laterally based pericranial flap. J Craniofac Surg. 2016;27(3):552-557.
7. Moshaver A1, Harris JR, Seikaly H. Use of anteriorly based pericranial flap in
frontal sinus obliteration. Otolaryngol Head Neck Surg. 2006;135(3):413-416.

51
CHAPTER
Endoscopic Correction of
Frontal Sinus Fractures
Patrick M. Colley, Kibwei A. McKinney, and Brent A. Senior
DEFINITION
■ Frontal sinus fractures involve the anterior or posterior table of the frontal
bone.
■ Displacement in frontal sinus fractures is classified as one width of the anterior
or posterior table.
ANATOMY
■ The frontal bone has both vertical and horizontal components.
■ The vertical component is the bone of the forehead and is composed of the
anterior and posterior tables.
■ The horizontal component makes up the superior orbital roof and floor of the
frontal sinus.
■ The vertical portion of the frontal bone contains a pneumatized frontal sinus in
greater than 90% of the population.
■ The frontal sinus begins its development at 4 years of age and continues to
develop until the late teenage years.
■ The anterior table of the frontal sinus is a bicortical structure made of
cancellous bone that begins at the nasofrontal suture line inferiorly and
averages 4 to 12 mm in thickness.
■ The posterior table of the frontal sinus is thinner than the anterior table, with
an average thickness of 0.1 to 4 mm. Its inner cortex is closely adherent to the
underlying dura.
■ The anterior and posterior tables of the frontal sinus converge inferiorly to
form the frontal recess or frontal sinus drainage pathway (FSDP), where the
frontal sinus drains into the middle meatus or ethmoid infundibulum,

depending on where the uncinate process inserts superiorly (FIG 1A,B).
■ At the superior-most portion of the FSDP is the frontal recess, a three-
dimensional (3D) structure with the following boundaries:
• Anterior—the agger nasi cell and/or the uncinate process
• Posterior—the anterior wall of the ethmoid bulla and any suprabullar
ethmoid cells
• Lateral—lamina papyracea of the orbit
• Medial—the lateral lamellae of the skull base and attachment of the middle
turbinate to the skull base
■ The soft tissue overlying the frontal bone consists of skin, subcutaneous soft
tissue, frontalis muscle, and pericranium.
■ At the glabella and medial portion of the supraorbital rim, the soft tissue is
thicker than it is at the superior portion of the forehead due to the presence of
the orbicularis oculi, procerus, and corrugator muscles.

FIG 1 • A. Sagittal drawing of the frontal sinus drainage
pathway (FSDP). The pathway passes posterior to the
agger nasi cell and anterior to the ethmoid bulla before
draining into the middle meatus. B. Coronal drawing
showing the most common relationship of the FSDP to
the lamina papyracea and middle turbinate. C. Anterior
view of the face showing the location of the
supratrochlear and supraorbital neurovascular bundles.
The supratrochlear bundle can be located
approximately 1.5 cm from midline, while the
supraorbital exits its foramen approximately 2.5 cm
from midline. CSM, corrugator supercilii muscle; PrM,
procerus muscle; StN, supratrochlear nerve; StA,
supratrochlear artery; StV, supratrochlear vein; SoN;
supraorbital nerve; SoA, supraorbital artery; SoV,
supraorbital vein; FrM, frontalis muscle. D. Endoscopic
view of the supratrochlear and supraorbital bundles.
StN, supratrochlear nerve; SoN, supraorbital nerve;
DSM, depressor supercilii muscle; CSM, corrugator
supercilii muscle; Ant. Table, anterior table of the frontal
sinus. External palpation can aid in orientation while

dissecting inferiorly and alert the surgeon when the
supraorbital rim is near.
■ The subpericranial plane constitutes a bloodless space and provides access to
the underlying anterior table of the frontal sinus.
■ The supraorbital and supratrochlear nerves supply sensation to the forehead
skin and course from the superior orbital rim, inferiorly, to the vertex of the
scalp, superiorly (FIG 1C,D).
■ The supraorbital nerve, the more lateral of these two structures, is a branch of
V1 that passes through the supraorbital foramen and travels deep to the
corrugator muscles, before penetrating the frontalis muscle and traveling
within the subcutaneous tissue in its superior course.
■ The supratrochlear nerve passes just above the superior oblique muscle and
its trochlea before coursing in a similar plane to the supraorbital nerve
superiorly along with the supratrochlear artery.
■ Injury to these nerves via trauma or surgical incision leads to a loss of
sensation superior to the site of injury.
PATHOGENESIS
■ The frontal bone is one of the stronger bones in the human body, and
fracturing it requires a pressure of 800 to 1600 ft-lb. However, an aerated
frontal sinus reduces the ability of the frontal bone to withstand pressure, thus
making pneumatized areas more susceptible to fractures than other regions of
the frontal bone.
■ The most common mechanisms of injury resulting in frontal sinus fracture are
motor vehicle collision (42%), assaults (14%), motorcycle collisions (10%),
pedestrians struck by motor vehicles (8%), and ballistic injuries (7%).1
■ The most common type of fracture is a combined fracture involving the
anterior and posterior tables as well as the FSDP, occurring between 55% and
67% of the time. Isolated anterior table fractures are seen in 33% of frontal
sinus fractures, with isolated posterior table fractures making up less than 5%.1
NATURAL HISTORY
■ Injury to the frontal sinus can lead to complications from cerebrospinal fluid
(CSF) rhinorrhea, damage to the FSDP, or changes in the aesthetic structure of
the facial skeleton.
■ The posterior table of the frontal sinus is thin and adherent to the underlying