Phẫu Thuật Tạo Hình (Tập 3): Sọ Mặt, Đầu Cổ Và Nhi Khoa – Neligan (Ấn bản 4)

923
Soft-tissue sarcomas
are four histologic types: embryonal, spindle-cell, alveolar,
and pleomorphic. Rhabdomyosarcomas have also found to be
present in multiple syndromes such as Li-Fraumeni, Beckwith
Wiedemann, and a subset in Gorlin syndrome.123
Diagnosis/patient presentation
Patients most commonly present with lesions in the head and
neck, genitourinary tract, and extremities.124 In the head and
neck, the most common presentations involve the orbit (20–
40%), nasopharynx, paranasal sinuses, and the middle ear.125
Embryonal tumors are found in 60% of cases, alveolar tumors
in 20%, and pleomorphic and spindle-cell tumors in 10% of
cases. Embryonal rhabdomyosarcomas occur between birth
and age 15 years and have a relatively favorable prognosis.
They are usually found in the head and neck and genitouri­
nary system. Spindle-cell rhabdomyosarcomas have a bimodal
distribution and are found in both children and adults. They
usually occur in the head and neck or paratesticular region.
Their prognosis is more favorable in children. Alveolar rhab­
domyosarcomas are relatively aggressive and are found in
adolescents and young adults. These tumors occur in the
extremities, head, and neck and genito-anal areas. Pleomor­
phic rhabdomyosarcomas usually affect adults in the sixth
and seventh decades of life.123 In general, the median age of
presentation for rhabdomyosarcomas is 5 years.126 These
tumors tend to present as fungating masses in the conjunctiva
and vagina or as obstructive masses in the genitourinary tract
and biliary system. They cause proptosis and diplopia when
they involve the orbit and neurologic manifestations when
they involve nerve roots in the paraspinal region. Rhabdo­
myosarcomas of the temporal bone present with hearing loss,
otalgia, and otorrhea (Fig. 41.14). CT scans of the head and
skull base, and lumbar puncture are used to evaluate for
extension of the disease into the skull, meninges, and brain.
Treatment/surgical technique
Treatment for the malignant lesion is wide local excision.
Reconstruction is deferred for 1 year while observing for
recurrence. Radiation may help for locoregional control.110
Benign lesions are completely excised. When the tumor
adheres to the skin, overlying skin is resected. Surgery is
generally curative and recurrence is rare.119 Treatment with
incision and curettement have been reported for large tumors
in cosmetically significant areas.
Postoperative care
Malignant lesions have a high likelihood of recurrence; thus
patients need to be observed for recurrence.
Outcomes, prognosis, and complications
The rate of recurrence of benign lesions is very low and
patients have an excellent prognosis. Metastatic spread occurs
in 6% of patients with malignant lesions.120 Metastatic lesions
are usually found in the lungs, but have also been reported in
the lymph nodes, liver, pleura, kidney, and heart.121
Soft-tissue sarcomas
Rhabdomyosarcoma
Introduction
Soft-tissue sarcomas account for 10% of all pediatric malig­
nancies, 50% of which are rhabdomyosarcomas.122 These
tumors are the third most common solid, extracranial, pedi­
atric tumor (after Wilm’s tumor and neuroblastoma) and are
diagnosed in about 250 patients annually.
Basic science/disease process
Rhabdomyosarcomas generally originate from mesenchymal
cells committed to becoming skeletal muscle cells. They have,
however, also been found to arise from viscera such as
the prostate, gallbladder, and urinary bladder. The tumors
resemble different stages of prenatal muscle formation. There
Fig. 41.14  Rhabdomyosarcoma. (Courtesy of Dr. Diane G. Heatley.)
Fig. 41.13  Excision of pilomatrixoma. (Courtesy of Dr. Delora L. Mount.)

924
SECTION III
CHAPTER 41 • Pediatric tumors
Treatment/surgical technique
The treatment of choice is surgical excision, with pre- or
postoperative radiation therapy. Adjuvant chemotherapy
may improve local control if the tumor size is >5 cm. The goal
of surgery is to obtain tumor-free margins of 1–3 cm.131–134
Outcomes, prognosis, and complications
The overall survival rates with surgery and radiation therapy
are shown to be 76% at 5 years and 57% at 10 years. Disease-
free survival rates have been shown to be 59% at 5 years and
52% at 10 years. The rate of local failure is below 20% but the
rate of metastatic spread at 10 years has been shown to be
44%. Tumors >5 cm in size have worse survival rates.134 Com­
plications at 5 years are 7%, and at 10 years are 9%. These
include fractures, fibrosis, soft-tissue necrosis, neuropathy,
and edema. Most common sites of metastases are lung (74–
81%), lymph nodes (12–23%), and bone (10–20%).135
Alveolar soft-part sarcoma
Introduction
Alveolar soft-part sarcoma is a rare neoplasm of unknown
etiology or histogenesis but has a poor prognosis.
Basic science/disease process
Alveolar soft-part sarcomas account for 1% of all soft tissue
sarcomas. They occur primarily in skeletal muscles or muscu­
lofascial planes of extremities, and in the head and neck region
in children.
Diagnosis/patient presentation
Children, adolescents, and young adults between the ages of
15 and 35 years are more likely to carry this diagnosis. The
tumor has a predilection for females and usually presents as
a soft, painless, slow-growing mass. The majority of patients
have metastases at the time of diagnosis.
Treatment/surgical technique
Wide local excision is the mainstay of treatment. Metastatic
spread occurs to lungs, bone, central nervous system, and liver.
Outcomes, prognosis, and complications
Survival has been reported as 82% at 2 years, 59% at 5 years,
and 47% at 10 years.136–138 Alveolar soft-part sarcomas can
recur more than 10 years after primary resection.
Lymphadenopathy
Introduction
About 30% of lymph nodes are found in the head and neck
region.139 Posterior auricular and occipital lymph nodes drain
the posterior scalp and the superficial portion of the postero-
superior neck.140 Preauricular and infraorbital nodes drain the
temporal scalp, lateral eyelids, conjunctiva, and cheek. These
nodes are connected to the parotid lymph nodes in the lateral
Treatment/surgical technique/postoperative care
Risk stratification is determined by pretreatment staging,
post-surgical clinical grouping, and tumor histology. All non-
metastatic embryonal rhabdomyosarcoma (ERMS) at favor­
able sites and completely resected tumors at non-favorable
sites are considered low risk. Non-metastatic alveolar rhabdo­
myosarcoma (ARMS) and incompletely resected ERMS at
non-favorable sites are intermediate risk, and distant metas­
tases are considered high risk. Primary treatment modalities
are multidrug chemotherapy and external beam radiation
therapy and protocols are adjusted based on risk stratification.
If complete remission is not obtained, adjuvant radiation
therapy and surgery are carried out. Surgical involvement
(staging and treatment) is mutilating and leads to functional
loss as a result. Primary excision should be attempted only if
complete excision can be accomplished without functional or
cosmetic consequences.127
Outcomes, prognosis, and complications
Patients undergoing the primary treatment modality have a
74% 5-year survival rate, while 33% have recurrent metastatic
disease that is fatal. Metastases occurs through blood or
lymphatic channels to lymph nodes, lungs, bones, or brain.126
Secondary procedures
Secondary excision may be considered after chemotherapy,
based on the judgment of the surgeon. If the tumor still
remains unresectable, then radiotherapy is employed.
Synovial soft-tissue sarcoma
Introduction
Synovial soft-tissue sarcomas are the most common soft-tissue
sarcoma of the hands and feet, and represent 8–10% of all
malignant somatic soft tissue neoplasms.
Basic science/disease process
These sarcomas arise from synovioblastic differentiation of
pluripotent mesenchymal stem cells. Histologic studies show
a biphasic pattern of pseudoepithelial cells and spindle cells
with a fibrosarcomatous appearance.128
Diagnosis/patient presentation
Synovial soft-tissue sarcomas present as solitary, well-
circumscribed lesions in the upper or lower extremities (80%).
They are para-articular, never arise within the joint, and are
not associated with normal synovial tissue. Non-extremity
sites include the trunk (8%), retroperitoneum/abdomen
(7%), and head and neck (5%).129 Common locations in
the neck include: parapharyngeal/retropharyngeal spaces,
larynx, pharynx, tongue, and tonsils.130 The most common
symptom is a painless mass that has existed for several
weeks to years. These lesions may also present as chronic
contractures, acute arthritis, bursitis, or as tumors following
trauma. Up to 30% of synovial soft-tissue sarcomas have
calcifications on radiographs. MR is the imaging modality of
choice and it shows the tumors to be sharply marginated and
largely cystic.

925
Lymphadenopathy
The papule progresses to a vesicle, then to a pustule, which
develops an eschar and then resolves. This is followed
by lymphadenopathy 1 week later. About 85% of patients
develop a deep enlarged lymph node at the site of inocu­
lation. Proximal lymph nodes may be skipped, with distal
level nodes developing lymphadenopathy.148,149 The disease
is self-limiting, but may lead to complications in 5–13%
of cases.
Treatment/surgical technique
Antibiotic therapy is used for highly symptomatic patients.
Surgical excision of enlarged lymph nodes is advocated if the
nodes become fluctuant.146
Outcomes, prognosis, and complications
Complications include encephalopathy, erythema nodo­
sum,
thrombocytopenic purpura, Parinaud oculoglan­
dular syndrome, and hepatitis.146,150 If the patient is
immunocompromised, then lymphadenopathy may progress
to bacillary angiomatosis, which is characterized by dissemi­
nated disease and cutaneous nodular lesions.
Cervical tuberculous adenitis (scrofula)
Basic science/disease process
Cervical tuberculous adenitis is caused by inhaled mycobac­
teria, which lead to a pulmonary infection. The infection
eventually spreads to regional lymph nodes via lymph vessels
or distal lymph nodes via blood vessels.151
Diagnosis/patient presentation
Scrofula typically presents in children under the age of 6 as
painless enlarging masses. Lower anterior and posterior cer­
vical lymph nodes are involved bilaterally. Tonsillar and
submandibular lymph nodes may also be involved. Symp­
toms include fever, weight loss, night sweats, and decreased
appetite. Lymph nodes will occasionally develop suppurative
changes and produce draining sinuses. Generalized lymph­
adenopathy can develop from miliary spread of the disease.
The diagnosis is made using ESR, tuberculin skin tests, chest
radiographs, and fine-needle aspiration.152
Treatment/surgical technique
Surgical excision is recommended to prevent the formation of
chronic draining fistulas, especially if open wounds are
present. If the tuberculin skin test is positive, cultures are sent
and four-drug therapy consisting of rifampin, isoniazid, pyra­
zinamide, and ethambutol is started. The course of treatment
is 6 months. Treatment may be tapered to two-drug therapy,
based on culture results.
Atypical non-tuberculous mycobacteria
Basic science/disease process
Mycobacterium
scrofulaceum
and
Mycobacterium
avium-
intercellulare are the most common atypical non-tuberculous
mycobacteria responsible for this lymphadenopathy. Both
organisms are commonly found in the southeastern US. The
parotid gland. Submandibular and submental nodes drain the
teeth, gum, tongue, and buccal mucosa. The deep cervical
lymph node chain runs along the internal jugular vein, deep
to the sternocleidomastoid muscles. Its superior portion
drains the tongue and the posterior pharynx. Its inferior
portion drains the larynx, trachea, thyroid, and esophagus.
Superficial cervical nodes lie superficial to the SCM. The
anterior chain of nodes runs along the internal jugular vein,
while the posterior chain is present in the posterior triangle.
These nodes receive drainage from the superficial tissues of
the neck, mastoid process, posterior auricular nodes, and the
nasopharynx. The tonsillar nodes drain the palatine tonsils.
Bacterial lymphadenitis
Basic science/disease process
Bacterial lymphadenitis usually occurs in children under 4
years of age and is preceded by an upper respiratory tract
infection or pharyngitis. It can present with mild fever, tender,
indurated, and erythematous lymph nodes, or systemic toxic­
ity. Submandibular nodes are affected in half of the patients.
Upper cervical nodes are affected in 25% of patients. The most
common causative organisms in children under the age of 3
years include Staphylococcus aureus and Streptococcus agalactiae
(Group G Streptococcus). Sepsis is most likely in this age group.
In children over the age of 3 years, Staphylococcus aureus and
Streptococcus pyogenes (Group A Streptococcus) are the most
common organisms. Bacterial lymphadenitis can also be
caused by Escherichia coli and anaerobes in the setting of
periodontal disease.
Diagnosis/patient presentation
Staphylococcus aureus adenitis is most likely to cause an abscess.
About 30% of acutely infected lymph nodes suppurate in 2
weeks.141,142 Group A Streptococcus adenitis causes bilateral
jugulodigastric node enlargement, fever, severe sore throat,
frontal headache, abdominal pain, toxic appearance, and
exudative tonsillitis. It may also present with minimal sys­
temic symptoms and non-tender adenopathy.
Treatment/surgical technique
Treatment of acute lymphadenitis abscess involves incision
and drainage. This prevents migration of the disease into the
chest and abdomen via fascial planes.
Chronic regional lymphadenopathy
Basic science/disease process
Cat scratch disease is the most common cause of chronic
regional lymphadenopathy affecting the head and neck region
in children and young adults.143–146 Up to 50% of the cases
involve head and neck nodes. The bacterial organisms
involved are Bartonella henselae and Afipia felis, which are
transmitted via a cat scratch or bite.147
Diagnosis/patient presentation
The clinical course of this disease begins with the forma­
tion of a red papule at 3–12 days at the site of inoculation.

926
SECTION III
CHAPTER 41 • Pediatric tumors
site of entry is the mouth, followed by spread to the regional
lymph nodes.
Diagnosis/patient presentation
Patients present with unilateral lymphadenopathy mainly
involving submandibular nodes. Nodes are initially painless
and mobile but eventually become inflamed, fixed, and sup­
purative (Fig. 41.15). Infection spreads locally to subcutaneous
surrounding tissues leading to chronically draining sinus
tracts. The age of presentation is between 1 and 5 years, and
patients usually do not have systemic symptoms. They have
a normal ESR, chest radiograph, and white cell count. Defini­
tive diagnosis is made through culture.153
Treatment/surgical technique
Definitive treatment involves surgical excision with or without
medical therapy. These organisms are more resistant to anti­
tuberculosis drugs. If there exists a suspicion for an atypical
mycobacterial infection, the treatment consists of a combina­
tion of clarithromycin, ethambutol, rifampin, and ciprofloxa­
cin while awaiting results.154
Fig. 41.15  Atypical mycobacterial abscess. (Courtesy of Dr. Dennis P. Lund.)
11. Jackson IT, Carbonnel A, Portparic Z, et al. Orbitotemporal
neurofibromatosis: classification and treatment. Plast Reconstr Surg.
1993;92:1–11. This article divides the clinical presentation of
orbitotemporal neurofibromatosis into three groups based on orbital and
soft tissue involvement and the state of the eye. The treatment methods
differ based on the severity of presentation and therefore this classification
helps guide the treatments used. The article presents 24 patients who are
followed for a maximum of 12 years.
31. Ferner RE, Gutmann DH. International consensus statement on
malignant peripheral nerve sheath tumours in neurofibromatosis
1. Cancer Res. 2002;62:1573–1577.
47. Sessions RB. Nasal dermal sinuses: new concepts and
explanations. Laryngoscope. 1982;92:1–28. This is a classic paper that
describes, evaluates, and unifies the various existing theories describing
the etiology of dermoids. The paper shows how dermoids and
encephaloceles are a continuum in the manifestation of congenital
anterior cranial base defects. The diagrams in the paper clearly illustrate
the surgical anatomy of these defects.
56. Hanikeri M, Waterhouse N, Kirkpatrick N, et al. The management
of midline transcranial nasal dermoid sinus cysts. Br J Plast Surg.
2005;58:1043–1050.
63. Kellman RM, Marentette L. The transglabellar/subcranial
approach to the anterior skull base: a review of 72 cases. Arch
Otolaryngol Head Neck Surg. 2001;127:687–690. This paper describes
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patients who have dermoids with intracranial extension. Through a
retrospective analysis of 72 cases in two academic medical centers it
analyses parameters such as average operating room time, complication
rates, and length of ICU stay, and compares them with results published
for traditional craniofacial approaches.
91. Schroeder JW, Mohyuddin N, Maddalozzo J. Branchial anomalies
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2007;137(2):289–295. This paper reviews the presentation, evaluation,
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105. Sistrunk WE. The surgical treatment of cysts of the thyroglossal
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114. McCulloch TA, Singh S, Cotton DWK. Pilomatrix carcinoma and
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121. Aslan G, Erdogan B, Aköz T, et al. Multiple occurrence of
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926.e1
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Reconstr Surg. 2005;116:13–19.
60. Goyal P, Kellman RM, Tatum IIISA. Transglabellar subcranial
approach for the management of nasal masses with intracranial
extension in pediatric patients. Arch Facial Plast Surg. 2007;9:
314–317.
61. Costantino PD, Janecka IP. Cranial-base surgery. In: Bailey BJ, ed.
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62. Fliss DM, Zucker G, Amir A, et al. The combined subcranial and
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63. Kellman RM, Marentette L. The transglabellar/subcranial
approach to the anterior skull base: a review of 72 cases. Arch
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the transglabellar/subcranial approach to the anterior skull base in
patients who have dermoids with intracranial extension. Through a
retrospective analysis of 72 cases in two academic medical centers it
analyses parameters such as average operating room time, complication
rates, and length of ICU stay, and compares them with results published
for traditional craniofacial approaches.
64. Moore CE, Ross DA, Marentette LJ. Subcranial approach to tumors
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65. Jung TM, TerKonda RP, Haines SJ, et al. Outcome analysis of the
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66. McQuown SA, Smith JD, Gallo AE Jr. Intracranial extension of
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68. Ackerman LL, Menezes AH. Spinal congenital dermal sinuses: a
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70. French BN. Midline fusion defects and defects of formation. In:
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71. Elton S, Oakes WJ. Dermal sinus tracts of the spine. Neurosurg
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72. McComb JG. Congenital dermal sinus. In: Pang D, ed. Disorders of
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73. French BN. The embryology of spinal dysraphism. Clin Neurosurg.
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74. Kanev PM, Park TS. Dermoids and dermal sinus tracts of the
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78. Martinez-Lage JF, Esteban JA, Poza M, et al. Congenital dermal
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79. Martinez-Lage JF, Masegosa J, Sola J, et al. Epidermoid cyst
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80. Schiffer J, Till K. Spinal dysraphism in the cervical and dorsal
regions in childhood. Childs Brain. 1982;9:73–84.
81. Pang D, Dias MS, Ahab-Barmada M. Split cord malformation: part
I. A unified theory of embryogenesis for double spinal cord
malformations. Neurosurgery. 1992;31:451–480.
82. Swift DM, Carmel PW. Congenital intradural pathology. Neurosurg
Clin N Am. 1990;1:551–567.
83. Hoffman HJ, Hendrick EB, Humphreys RP. The tethered spinal
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84. Eller TW, Bernstein LP, Rosenberg RS, et al. Tethered cervical
spinal cord. Case report. J Neurosurg. 1987;67:600–602.
85. Smith KA, Rekate HL. Delayed postoperative tethering of the
cervical spinal cord. J Neurosurg. 1994;81:196–201.
86. Thaller SR, Bauer B. Cysts and cyst-like lesions of the skin and
subcutaneous tissue. Clin Plast Surg. 1987;14:327–340.
87. Pryor SG, Lewis JE, Orvidas LJ. Pediatric dermoids cysts of
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88. Telander RL, Filston HC. Review of head and neck lesions in
infancy and childhood. Surg Clin North Am. 1992;72:1429–1447.
89. Fetter H. Benign congenital neoplasms: dermoids and teratomas.
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90. Bloom D, Carvalho D, Edmonds J, et al. Neonatal dermoid cyst of
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91. Schroeder JW, Mohyuddin N, Maddalozzo J. Branchial anomalies
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and treatment of branchial anomalies. It accomplishes this task through a
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anomalies who were treated over a 10-year period. The associated
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discussed.
92. Wild G, Mischke D, Lobeck HN, et al. The lateral cyst of the neck:
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94. Nusbaum AO, Som PM, Rothschild MA, et al. Recurrence of a
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926.e3
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CHAPTER 41 • Pediatric tumors
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otolaryngology experience. Clin Otolaryngol. 2001;26:
243–248.

SECTION III • Pediatrics
42 
Conjoined twins
Oksana Jackson and David W. Low
SYNOPSIS
■ Conjoined twins are one of the most uncommon congenital anomalies,
with an incidence between 1 in 50 000 and 1 in 100 000 births.
■ Conjoined twins are classified by dorsal or ventral site of fusion and
anatomic region of fusion.
■ Separation of conjoined twins requires a multidisciplinary team
approach.
■ Understanding the shared anatomy through preoperative imaging
studies and investigations is critical to successful separation.
■ Careful planning and insertion of tissue expanders is almost always
necessary to accomplish wound closure.
■ Intensive care monitoring and support, nutritional supplementation, and
pressure-reducing strategies are essential for successful separation.
Access the Historical Perspective section online at

candidates for separation.14 In all reports, females predomi­
nate over males by approximately 3 : 1. However, in reports
of stillborn conjoined twin pairs, males predominate over
females.5,10,15–17
Classification
A number of classification systems exist and each categorizes
conjoined twins by their most prominent site of union together
with the suffix pagus, a Greek word meaning “that which is
fixed”. The most commonly used system, both clinically and
historically in the literature, was adapted from that proposed
by Potter and Craig, and simplified to include the five most
common forms of conjoined twinning, listed here in order of
decreasing frequency: thoracopagus, omphalopagus, pygopa­
gus, ischiopagus, and craniopagus.18 These five types are
summarized below and illustrated in Fig. 42.4. Additionally,
the number of shared anatomic structures can be described
with the prefixes “di-”, “tri-”, and “tetra-”, combined with the
involved parts, “prospus” (face), “brachius” (upper extrem­
ity), and “pus” (lower extremity). For example, ischiopagus
twins may have three (tripus) or four (tetrapus) legs.
The thoracopagus type is the most common, occurring in
74% of cases. Infants with this form of twinning face each
other, have major junctions between the chest and abdomen,
and may have conjoined livers, hearts, and upper gastro­
intestinal structures (Fig. 42.5; Case 6, below). Separation may
be limited by the degree of cardiac involvement. Conjoined
six-chamber hearts are common in thoracopagus twins and
have never been separated successfully; only a single success­
ful case of separation of twins with conjoined atria has been
reported.19 Advances in prenatal diagnosis and the develop­
ment of fetal surgery have improved perinatal survival in
cases where separation is deemed appropriate. For example,
the EXIT procedure (ex utero intrapartum treatment) has been
recently used at the Children’s Hospital of Philadelphia in the
separation of thoracopagus twins. In this case, one twin had
a normal heart that perfused a co-twin with a rudimentary
heart, and EXIT allowed prompt control of the airway and
Figs. 42.1–42.3
appear online only.
Basic science/disease process
Incidence
Conjoined twins are one of the most uncommon congenital
anomalies. The typical form of monozygotic twinning occurs
in 4 per 1000 live births, and dizygotic fraternal twinning in
approximately 10–15 per 1000. Twin births therefore occur in
about 1 in 90 live births.12 The incidence of conjoined twins
has been estimated at between 1 in 50 000 and 1 in 100 000
pregnancies. Spencer has reported that 1% are stillborn
and 40–60% die shortly after birth, so the true incidence is
closer to 1 : 200 000 live births.5,13 Recent reports of prenatally
diagnosed conjoined twins indicate that more than one-
quarter of cases die in utero and one-half die immediately
after birth, leaving only 20% potential survivors who are

927.e1
Historical perspective
Historical perspective
Society has been fascinated with conjoined twins since antiq­
uity. Attitudes have evolved from suspicion and fear with
subsequent ostracization from society on religious grounds,
to exploitation and exhibitionism, to the modern-day intense
media interest in rare medical conditions, treatments, and
cures. In classical times, gross anomalies were considered a
warning from the gods. Scholars, including Aristotle and
Hippocrates, thought the unborn child was susceptible to
external stimuli. Thus, maternal impressions, and sins of the
parents, were often blamed for “monstrous births”, and con­
joined twins were considered prototypical examples. Those
who survived were often treated as religious and social
outcasts.1–3
Early theories focused on anatomic factors and male fertil­
ity. Aristotle, in his textbook, De Generation Animalium, theo­
rized that conjoined twins were the result of a womb that was
too small and constrained the seed of twins, causing them
to become congested and joined. Hippocrates reportedly
believed that too great a quantity of seed was responsible for
multiple births and conjoined twinning, whereas one “lacking
in quantity” was thought to lead to limb agenesis and missing
body parts.3
The earliest examples of conjoined twins are artifactual and
include a 17.2 cm marble statue of female parapagus twins
dating from the 6th millennium BC. Called the “double
goddess”, this portrayal of the sisters of Catalhoyuk is housed
in the Anatolian Civilization Museum in Ankara, Turkey.4
Another early representation is a stone carving of pygopagus
twins discovered in Fiesole, Italy, dated to 80 BC and currently
housed in the San Marco Museum in Florence (Fig. 42.1).5,6
The first well-documented case of conjoined twins is that
of the Maids of Biddenden, Mary and Eliza Chulkhurst, who
were born in England in the year 1100 and survived into adult
life, joined laterally from hips to shoulders. When one twin
died at the age of 34 years, the second twin refused to be
separated from her sister, saying, “as we came together we
will also go together”, and subsequently died 6 h later.7 The
earliest documented case of craniopagus twins is of girls born
near Worms, Germany, in 1495, who lived to the age of 10
years and whose birth was interpreted at the time as a sign of
God’s displeasure. They were joined at the forehead, as
depicted in a woodcut circa 1496 (Fig. 42.2).8,9
Perhaps the most famous pair of conjoined twins were Eng
and Chang Bunker, who were born in Siam in 1818 (Fig. 42.3).
They were taken to the US by a traveling Scottish merchant,
and they gained notoriety there, after PT Barnum exhibited
them as “Siamese twins” in his travelling Barnum and Bailey
Circus – hence the derivation of the colloquial term. Despite
their abdominal connection, they married sisters, fathered 22
children, and lived together for 63 years.10
The earliest attempt at separation is recorded as occurring
in Kappadokia, Armenia in 970 AD. This was an unsuccessful
attempt to separate male ischiopagus twins at age 30 after one
twin died.5 The first reported successful separation of con­
joined twins was performed in 1689 in Basel, Switzerland. The
surgeon, Johannes Fatio, separated a pair of omphalopagus
twins. Koenig, another surgeon who was an observer at the
procedure, published the case as his own, and thus is fre­
quently credited with the first successful conjoined twin
separation.11
Fig. 42.1  Stone carving of pygopagus twins dated to ~80 BC, Fiesole, Museo San
March, Florence, Italy. (Reproduced from Spitz L. Surgery for conjoined twins. Ann
R Coll Surg Engl. 2003;85:230–235.)
Fig. 42.2  Woodcut of craniopagus twins circa 1496, thought to be the earliest
representation of craniopagus twins from real life. (Reproduced from Winston KR.
Craniopagi: anatomical characteristics and classification. Neurosurgery.
1987;21:769–781.)

927.e2
SECTION III
CHAPTER 42 • Conjoined twins
Fig. 42.3  Chang and Eng, xiphopagus twins. From an oil painting by Irvine in the
Royal College of Surgeons of England. (Reproduced from Spitz L. Surgery for
conjoined twins. Ann R Coll Surg Engl. 2003;85:230–235.)

928
SECTION III
CHAPTER 42 • Conjoined twins
leg. In a unique case, Zuker et al. reported successful trans­
plantation of an entire extremity from a dying twin to her
sister, thus leaving the surviving one with two functional
legs.20
The least common and perhaps the most difficult to sepa­
rate is the craniopagus type because the cranial union often
involves a variety of neural and vascular connections.12,21,22
Craniopagus twins represent 2–6% of conjoined twins and
occur with an incidence of one in 2.5 million births.9 They can
share scalp, calvarium, dural sinuses, and surfaces of the brain,
but the face, foramen magnum, and spine remain separate.
Even when the cerebral cortices are contiguous, craniopagus
twins do not share neuronal pathways, as demonstrated by
completely independent behavior and by electroencephalo­
gram studies. Facial and skull asymmetry can occur, as well
as other intracranial and extracranial abnormalities. The site
of fusion can vary significantly, and rotation about this site of
union can produce a variety of anatomic orientations.3,8,21,23 A
number of authors have classified craniopagus twins by the
site, degree of fusion, or alignment of the twins.24,25 The more
circulation prior to clamping the umbilical cord, leading to
survival of the normal co-twin.14
In omphalopagus twins, there is fusion in the abdominal
area with variable connections of the liver, biliary tree, and
gastrointestinal tracts. In isolated omphalopagus forms, there
is no cardiac connection (Case 8, below).
Pygopagus twins are joined at the level of the sacrum and
commonly face away from each other. There is usually a
shared spinal cord, and the perineal structures and rectum
also may be fused. Pygopagus twins represent about 17% of
conjoined twins.12
In the ischiopagus type, the junction is at the pelvic level
with sharing of the genitourinary structures, rectum, and liver
(see Fig. 42.5; Cases 5 and 7, below). These twins may each
have a single normal leg and a common fused leg, referred to
as a tripus, or four legs may be present. The tripus, when
present, usually has dual neural and vascular supply and
preoperative determination of perfusion is important in plan­
ning separation. Often, the tripus is sacrificed and the soft
tissue used for closure of each twin, leaving each with a single
Thoracopagus
A
Omphalopagus
B
Pygopagus
C
Fig. 42.4  Clinical classification of conjoined twins: (A) thoracopagus, (B) omphalopagus, (C) pygopagus, (D) ischiopagus tetrapus, (E) ischiopagus tripus, and
(F) craniopagus.
Ischiopagus tetrapus
Ischiopagus tripus
Craniopagus
D
E
F

929
Basic science/disease process
abdominal viscera or the umbilicus. Ventral unions are further
subdivided into rostral, caudal, or lateral. These eight types
with their definitions and restrictions are listed below.26
Ventral
Rostral
1. Cephalopagus: fused from the top of the head to the
umbilicus.
2. Thoracopagus: united from the upper thorax to the
umbilicus and always involving the heart.
3. Omphalopagus: joined primarily in the area of the
umbilicus and never including the heart.
Caudal
4. Ischiopagus: united from the umbilicus through the
pelvis and sharing external genitalia and anus.
Lateral
5. Parapagus: sharing a conjoined pelvis with one
symphysis pubis and one or two sacrums (see Fig. 42.7E).
Dorsal
6. Craniopagus: united on any portion on the skull except
the face or foramen magnum, and the trunks are never
united.
common phenotypic variations described in case reports in
the literature are illustrated in Fig. 42.6.
An alternative classification system was proposed by
Spencer, based on the analysis of embryologic data and the
teratology of over 1200 cases. She divided conjoined twins
into dorsal and ventral forms of union, joined in one of eight
anatomic sites (Fig. 42.7). This classification system specifi­
cally defines and restricts the anatomy of fusion between the
different types of conjoined twinning, thus attempting to
standardize the nomenclature for purposes of predicting sepa­
rability, surgical planning, and outcomes after surgery, as well
as for consistent documentation for research purposes.26 In
Spencer’s embryologic classification system, ventral unions
are oriented ventrally or ventrolaterally, and the union always
includes the umbilicus, whereas dorsal unions are united
dorsally or dorsolaterally and do not include the thoracic or
Thoracopagus
Shared pericardium
A
Fig. 42.5  Within each type of union, the anatomy of conjoined twins can be quite
variable. The anatomic features on the left of the illustration describe the anatomy
of the twins depicted on the right. These are examples of two common types,
amenable to surgical separation. (A) Thoracopagus twins with separate hearts but a
shared pericardium. (B) Tetrapus ischiopagus twins with shared intestine from distal
ileum and single colon, rectum, and anus.
Ischiopagus
Shared distal ileum,
colon and rectum
B
Fig. 42.6  The more common phenotypic variation of craniopagus conjoined twins.
Frontal
Parietal
Temporoparietal
Occipital
Type I
Type II
O’Connell’s classification of vertical craniopagus
Type III
A
B
C
E
F
G
D

930
SECTION III
CHAPTER 42 • Conjoined twins
Cephalopagus
A
Thoracopagus
B
Omphalopagus
C
Ischiopagus
D
Parapagus, one sacrum
E
Parapagus, two sacrums
F
Cranioopagus
G
Pygopagus
H
Rachipagus
I
Fig. 42.7  (A–I) The eight types of conjoined twins, as classified by Rowena Spencer26 based on the theoretical site of union and divided into ventral and dorsal forms of
junction.

931
Diagnosis/patient presentation
conjoined twins united dorsally “float” in a shared amniotic
cavity, and those united ventrally “float” on the sphere of a
shared yolk sac. In both cases, they can be oriented from
rostral to caudal, depending on the relative temporal–spatial
relationship of the embryonic discs during fusion (Fig. 42.8).28
Diagnosis/patient presentation
Prenatal evaluation
The diagnosis of conjoined twins can be made as early as the
12th week of gestation on prenatal ultrasound. First-trimester
or early second-trimester ultrasound findings suggestive of
conjoined twins include a fixed position of the twin bodies on
serial examinations; lack of a separating membrane between
the twins; and inability to separate the fetal bodies and skin
contours.29,30 Once the diagnosis is suspected, evaluation
should continue with serial ultrasound, magnetic resonance
imaging (MRI), and echocardiography to define better the
extent of the union and the anatomy of the shared organs, to
determine the presence of any associated abnormalities, and
to monitor the pregnancy for complications (Fig. 42.9).14
Careful cardiac evaluation is essential, given the high
incidence of thoracopagus types. Both ultrafast fetal MRI with
3D reconstruction and echocardiography are useful in deter­
mining the cardiac structure and function. Prenatal echocar­
diography may be superior to postnatal scans because the
amniotic fluid provides a good buffer for scanning, and
positioning of the transducer may be difficult postnatally
against the small pericardial window. Delineation of the
conjoined cardiac anatomy has been achieved as early as the
20th week of gestation, although third-trimester studies are
most reliable; even those may underestimate the severity of
disease when compared with autopsy studies.12,14,29 Echocar­
diography can also be utilized while on placental support
during the EXIT procedure, as was reported by Mackenzie
et al. at the Children’s Hospital of Philadelphia and proved
critical in delineating the relationship of the great vessels in
preparation for immediate separation.14
The presence of other anomalies, even in organ systems not
related to the conjoining, may affect survival, and need also
to be ascertained prenatally. Observed anomalies include
congenital diaphragmatic hernia, abdominal wall defects,
neural tube defects, club foot, imperforate anus, esophageal
atresia, and cystic hygroma.14 Serial scans are also necessary
to monitor the pregnancy for the unique complications that
are known to occur in multifetal gestations such as twin–twin
transfusion syndrome, co-twin demise, and oligohydramnios-
polyhydramnios sequence, as well as for the effects of cross-
circulation on the pregnancy such as polyhydramnios and
hydrops. Polyhydramnios is noted in 50% of cases of con­
joined twin gestations and may require treatment during
pregnancy to prevent complications such as preterm labor.12,31
Ethical, religious, and moral issues surrounding conjoined
twin pregnancies and separation are complex. Accurate pre­
natal diagnosis and early determination of the extent and
severity of the twin union enable determination of the feasi­
bility of separation and prediction of postnatal outcomes. This
is critical in early counseling of families, so that the options
of termination versus near-term cesarean delivery can be
discussed. Elective termination is recommended in cases
7. Pygopagus: sharing sacrococcygeal and perineal regions,
and sometimes the spinal cord.
8. Rachiopagus: fused dorsally above the sacrum, and
exceedingly rare.
Asymmetrical forms of conjoined twinning often occur,
resulting in a smaller and larger twin; these are termed “para­
sitic” followed by their closest classification. When one twin
is significantly smaller and less well developed, it is often
malnourished and has other physiologic problems which
can complicate potential separation. On some occasions, the
smaller twin may die and much of the deceased twin may be
absorbed. Conjoined twins whose union and anatomy are
intermediate between different types are termed “atypical
conjoined twins”.26
Etiology
Two theories have been proposed to explain the embryology
resulting in conjoined twins. The classic theory of incomplete
fission, described by Zimmerman,27 proposes that there is
incomplete separation of the embryonic discs of twins arising
from a uniovular gestation between 13 and 16 days after fer­
tilization. More recently, Spencer28 proposed an alternative
theory of secondary fusion of two originally separate mon­
ovular embryonic discs. This theory postulates that, during
the 3rd or 4th week of development, previously separate
embryonic discs reunite either dorsally or ventrally at specific
sites where the surface ectoderm is either absent or normally
programmed to fuse or break down. These sites include the
anlage of the heart, the diaphragm, the oropharyngeal and
cloacal membranes, the neural tube, and the periphery of the
embryonic discs, each site corresponding to specific types of
conjoined twinning. The unions are always homologous,
meaning the fusion occurs head to head, tail to tail, front to
front, back to back, or side by side – but never head to tail or
front to back. Spencer’s “spherical theory” proposes that
J
(J) Parapagus conjoined twins with a single pelvis.
Fig. 42.7, cont’d

932
SECTION III
CHAPTER 42 • Conjoined twins
Primitive
streak
Amniotic sac
Yolk sac
Embryonic
disc
Embryonic disc
A
Thoracopagus
Rostral
B
Parapagus
Caudolateral
C
Ischiopagus
Caudal
D
Rostral
Yolk sac
Shared
amniotic sac
Yolk sac
Cranioopagus
E
Fig. 42.8  Spencer’s “spherical theory” of union of two embryonic discs. (A) Normal
trilaminar embryo at 3–4 weeks. Embryonic discs united ventrally, “floating” on the
sphere of a shared yolk sac oriented (B) rostrally (thoracopagus), (C) caudolaterally
(parapagus), and (D) caudally (ischiopagus). Embryonic discs united dorsally,
“floating” in a shared amniotic cavity oriented (E) rostrally (craniopagus),
(F) mid-dorsally (rachipagus), and (G) caudally (pygopagus).
Caudolateral
Rachipagus
F
Caudal
Pygopagus
G

933
Treatment/surgical technique
The obvious advantages of delayed separation include dimin­
ished risks of anesthesia, ability to confirm the anatomy and
evaluate for other congenital anatomies, and the ability to
ensure adequate wound coverage with preseparation tissue
expansion.12,14,15,32
Preoperative planning
Elective separation may take place as early as 2–4 months
after delivery. Maintenance in an intensive care setting during
this time allows for close monitoring and stabilization of the
infants, and nutritional supplementation as necessary to
optimize growth and development preoperatively. Detailed
postnatal investigations continue to confirm the conjoined
anatomy and other possible congenital anomalies. Computed
tomography scanning in addition to MRI may provide useful
information about shared organs as well as skeletal anatomy,
while MRI is preferred for delineating vascular anatomy;
gastrointestinal contrast studies and angiography also may be
utilized but have been less helpful.3,10
Assembly of a multidisciplinary team of various surgical
subspecialists, neonatologists, anesthesiologists, and nurses,
as well as the development of a comprehensive surgical and
perioperative management plan, is critical to the success of
twin separation. Two distinct anesthesia and surgery teams
should be assembled, and the anesthetic management plan
and operative steps in separation should be predetermined
and reviewed. Both schematic diagrams as well as 3D models
may be useful in planning separation.3,33 Logistic details,
including patient positioning, placement of lines and moni­
tors, and operative room set-up and instrumentation, should
not be overlooked.
Essential preoperative planning also includes proposed
management of the soft tissues at the time of separation. If the
shared anatomy allows for separation and survival of both
twins, then wound closure becomes a critical issue. Assess­
ment of the anticipated soft-tissue deficiency will determine
the need for preseparation tissue expansion to accomplish
stable wound closure. Without adequate skin coverage, the
child is at risk for exposure of important viscera, frank evis­
ceration, and sepsis. If the closure is too tight, embarrassment
of cardiac and pulmonary function can occur, which can be
fatal. Additional support materials may be necessary when
large defects of the body walls, particularly the chest,
abdomen, and pelvic floor, are created after separation. The
plastic surgeon, therefore, is an essential member of the surgi­
cal team attempting twin separation.
Delineation of the vascular skin territories is important in
planning the line of separation between co-twins, especially
in cases of ischiopagus tripus where the common leg is to be
sacrificed and the soft tissue divided for reconstruction and
closure of both twins. Although magnetic resonance angiog­
raphy and angiographic studies can illustrate large-vessel
anatomy and extremity perfusion, they are inadequate at
assessing the precise vascular territories of the skin at the level
of the pelvis and along the extremity. Fluorescein previously
has been used to evaluate perfusion and viability of skin flaps,
ischemic extremities, injured bowel, and burn wounds.34–38
The traditional fluorescein test uses qualitative visual assess­
ment of tissue fluorescein delivery by inspection under
ultraviolet light. A quantitative technique of intravenous fluo­
rescein mapping employing a fiberoptic perfusion fluorometer
where there is cerebral or cardiac fusion, and parents may also
elect termination when the anticipated severity of deformity
and quality of life following separation is unacceptable.12
Early assessment also provides time for parental adjustment
and predelivery planning; the involvement of psychologists,
social workers, and ethicists may be beneficial in this decision-
making and counseling process.
Treatment/surgical technique
Obstetric management
Near-term cesarean delivery at 36–38 weeks’ gestation after
confirming lung maturity and delivery at or near a pediatric
surgical center is the recommended obstetric management.
Although a number of vaginal deliveries have been reported
in the literature, cesarean section is preferred for the safest
management of the fetuses and the mother. Cesarean section
also provides the opportunity for utilizing the EXIT procedure
for the management of twins expected to have rapid cardiac
deterioration.
Twins who survive delivery fall into three groups, deter­
mined predominantly by their cardiac anatomy: those who
die shortly after birth, those who survive to planned separa­
tion, and those who require emergent separation after birth.
Those who do not require emergent separation have a survival
rate of 80–90% in most series. Emergent separation is required
when one twin is dead or dying and threatening the survival
of the other twin, or when a life-threatening and correctable
congenital anomaly is present in one or both twins such
as intestinal atresia, malrotation, ruptured omphalocele, or
anorectal agenesis. Survival in this situation falls to 30–50%.
Fig. 42.9  Prenatal magnetic resonance imaging of ischiopagus twins with
conjoined livers and colon and a cloacal malformation (Case 7).

934
SECTION III
CHAPTER 42 • Conjoined twins
to cover deficient areas of skin and also to reconstruct fascial
defects.42–44 As in traditional abdominal wall and chest wall
reconstruction, both synthetic and biologic materials can be
utilized, although biologics are much preferred in the pediat­
ric population and where soft-tissue coverage may be precari­
ous. Dermal replacement materials and other biologic meshes
are favorable because they are quickly revascularized and
promote ingrowth of new tissue; thus they are compatible
with growth and are easily managed if exposure occurs.45–47
Random-pattern or arterialized flaps of skin or skin and
muscle can be used for coverage of small defects. Few case
reports from the literature describe their use for coverage
other than utilization of the third leg with fillet and sacrifice
of the tripus. Indeed, many of the successful ischiopagus
tripus separations have used the third leg for soft-tissue
coverage.
Pneumoperitoneum has been reported by several surgical
groups in the past. Mestel et al. utilized pneumoperitoneum
in an ischiopagus tripus twin pair. They injected 500–1500 cc
of air every 3 days and were able to increase the abdominal
circumference by 12 cm. At separation, there was insufficient
skin and the tripus was sacrificed to achieve a successful
closure.48 Yokomori et al. used pneumoperitoneum in conjunc­
tion with tissue expanders in an ischiopagus tripus twin pair,
but again the tripus was sacrificed for successful coverage at
the time of separation.49 Wen-Sung Hung and co-workers also
utilized pneumoperitoneum in an ischiopagus tripus with
twice-weekly injection of 500–1500 cc of air. The circumference
was reported by Ross et al.39 as helpful in defining the vascular
territories and the line of separation between a pair of com­
plicated ischiopagus twins at the Children’s Hospital of Phila­
delphia in 1984 (Fig. 42.10).39,40
Role of the plastic surgeon
The separation of conjoined twins challenges the plastic
surgeon to provide sufficient soft tissue to cover a significant
area of intrinsic deficiency. Twin separation is analogous to
separation of a simple or complex syndactyly, a congenital
anomaly well known to plastic surgeons. As in the separation
of syndactyly, insufficient tissue is present for resurfacing the
conjoined interface so that skin grafts are generally needed,
except in the simplest types. Similarly, the soft-tissue deficit
in conjoined twins is twice the surface area of the canal joining
the twins.41 A variety of methods for providing soft-tissue
coverage have been reported in the literature and include the
use of skin grafts and skin substitute products, local skin
flaps, pneumoperitoneum, and tissue expansion.
Skin grafting represents the least useful primary method of
coverage in these patients. Skin grafting can be used only in
the smallest of defects and requires an intact body wall for a
bed. Only under the most extreme circumstances would a skin
graft primarily be applied to abdominal viscera, although skin
grafting is often used secondarily to treat wound-healing
complications, not uncommon after twin separation. Today,
various skin substitute products are available and can be used
Fig. 42.10  (A–C) Technique of dermofluorometry demonstrating differential skin
perfusion of the pelvis and lower extremities in a case of ischiopagus tripus twins.
(Reproduced from Ross AJ 3rd, O’Neill JA, Jr., Silverman DG, et al. A new technique for
evaluating cutaneous vascularity in complicated conjoined twins. J Pediatr Surg.
1985;20:743–746.)
50
25
o
oo
o o
o
55
37
Twin B
Twin A
A
86
81
200
110
61
33
26
31
37 30
37
27
75
90
Twin B
Twin A
B
Twin B
Twin A
C

935
Treatment/surgical technique
Fig. 42.11  Thoracopagus and ischiopagus twins prior to separation. Tissue
expanders were used for the first time at the Children’s Hospital of Philadelphia in
1980 to generate additional skin prior to separation.
was increased by 19 cm, but again, the third leg was sacrificed
for closure.50 Although infection was felt to be a potential
risk of pneumoperitoneum, it was not encountered by any of
the investigators. In all three cases, however, an insufficient
amount of soft tissue was generated to achieve successful
closure without sacrifice of the third shared leg.
Tissue expansion represents a great advance in the ability
to provide adequate soft-tissue coverage for the separation of
conjoined twins. Although Neumann first introduced the
concept in 1957, it was not until 1976 that tissue expansion
became popular, with the introduction of the Radovan
expander.51,52 Since then, tissue expansion has been used
widely by plastic surgeons for a variety of conditions where
additional skin is needed. The first report of the successful use
of tissue expansion for the separation of conjoined twins was
by Zuker and his co-workers in 1986 for the successful separa­
tion of an ischiopagus conjoined twin pair. Five subcutaneous
and two intraperitoneal expanders were used. One twin was
closed successfully, but in the second, Marlex mesh reinforce­
ment of the abdominal wall and split-thickness skin grafting
were needed to complete the closure.53 Numerous reports
have followed, utilizing tissue expansion in both the intra­
peritoneal and subcutaneous positions.41,53–55
We advocate subcutaneous tissue expansion with place­
ment of the maximum number of tissue expanders possible
in all areas surrounding the canal separating the infants. They
should be placed on the extremities in tripus cases as well, to
facilitate harvest of adequate skin and subcutaneous tissue
flaps without sacrifice of the lower extremities. Smooth-walled
over-textured tissue expanders should be used for two
reasons. In infants, the subcutaneous tissue layer is thin.
Tissue expanders with a hard backing produce sharp edges,
which can gradually erode through the skin at the margin of
the expander. In addition, capsule formation is reduced with
a textured implant surface, and thus prevent further thinning
of the skin. Distant ports rather than integral ports are also
preferred for the same reason. The thin skin overlying the
tissue expander is subject to breakdown from repeated injec­
tions during the expansion process, thus increasing the risk
of expander exposure with integral ports.
Clinical experience
The following 10 cases review the authors’ experience with
the separation of conjoined twins at the Children’s Hospital
of Philadelphia between 1980 and 2012. These examples
highlight the lessons learned and present principles in surgi­
cal technique and patient management that may be helpful to
future teams attempting conjoined twin separation.
Case 1  Thoracopagus and ischiopagus twins (1980)
Separation of this male thoracopagus and ischiopagus twin
pair (Fig. 42.11) was performed at 2.3 years of age and
represented the first use (1980) of tissue expanders in this
series. One large circular 1000 cc Radovan expander was
inserted beneath their shared abdominal skin through an
incision in the xiphoid region and the umbilicus was
released from its attachment to the abdominal wall. Despite
the extra skin generated, it was inadequate and resulted in a
tight closure on the smaller twin, resulting in
cardiopulmonary insufficiency and death. His skin was
harvested and was frozen for eventual use for coverage of
open wounds on the surviving twin. The skin grafts were
frozen in liquid nitrogen after sequential passage through
increasing concentrations of glycerol in saline, as described
by Lehr and co-workers.56 Closure of the surviving twin was
achieved using the capsule along with the expanded skin.
Granulation tissue developed on the capsular surface over
the ensuing days and was successfully grafted with skin that
had been harvested from the deceased twin.
Case 2  Ischiopagus twins (1984)
This ischiopagus tripus conjoined twin pair were joined
from the sternum to the pelvis with a shared liver, terminal
ileum, and colon. Each twin had a separate normal lower
extremity and a shared extremity. Fluorescein studies were
used in this case and proved quite helpful in assessing the
territories of skin perfusion and determining the lines of
separation. Preoperative studies demonstrated a clear line of
separation along the pelvis and extremity with the blood
supply to the extremity predominantly coming from twin A.
The twins were separated along this line and the extremity
was given to twin A. A pedicled flap from the shared thigh
based on the lower abdomen of twin B was used to complete
the cutaneous closure of twin B. Injection of fluorescein was
performed again intraoperatively to assess the viability of
this pedicled flap prior to closure and any non-viable tissue
was trimmed. Because the knee joint of the shared extremity
was not stable, the knee was disarticulated and the distal
flap of skin and muscle used to complete the closure of twin
A (see Fig. 42.10).

936
SECTION III
CHAPTER 42 • Conjoined twins
Fig. 42.13  (A) Thoracopagus and omphalopagus twins.
A
Fig. 42.12  Ischiopagus tripus twins – the abnormal tripus extremity is clearly
demonstrated.
Case 3  Omphalopagus and ischiopagus twins (1988)
This omphalopagus and ischiopagus twin pair had a less
complex connection between the infants from xiphoid to
pelvis. They were treated with a single 1000 cc Radovan
expander beneath the shared abdominal skin. The expander
was introduced through a single incision in the xiphoid
region with release of the umbilicus. Expansion was initiated
in the hospital but was completed on an outpatient basis. A
successful surgical separation with complete skin coverage
was achieved without difficulty at 14.5 months of age,
without the need for skin grafts.
Case 4  Ischiopagus twins (1992)
In this ischiopagus twin pair, additional expanders were
used because of the soft-tissue inadequacy experienced in
the first twin pair separation. At 3 months of age, a 700 cc
round Radovan expander was used to expand the conjoined
abdominal region and two smaller 250 cc rectangular
expanders were used on the back, all with remote ports. At 4
days postoperatively, some skin necrosis was evident in the
upper abdomen and the twins were taken back to the
operating room. The area of necrosis was excised and the
single abdominal tissue expander was replaced with two
smaller 250 cc expanders. The patients were initially treated
on a regular bed mattress with frequent, regular rotation
from the abdomen to the back. Despite this, chronic pressure
on their backs caused a threatened exposure of the posterior
expanders. Transfer to a Clinitron bed improved the
situation to some degree but the skin continued to thin over
the posterior expanders. This prompted earlier surgical
separation, which was performed at 5 months of age. The
expanded abdominal skin was converted into bipedicled
flaps to achieve closure and the remaining defects were
grafted with autogenous split-thickness skin grafts. Once
again, despite the use of additional expanders, there was
insufficient soft tissue for complete wound coverage with the
expanded skin. Further expansion would have been desirable.
Case 5  Ischiopagus tripus twins (1993)
This ischiopagus tripus twin pair were treated at 3.5 years of
age using multiple rectangular tissue expanders. Two
expanders were placed on the shared lower extremity, one
on the anterior aspect and the other on the posterior aspect
of the upper thigh; another was inserted on the back; and
two more were placed in the abdominal region (Fig. 42.12).
They were expanded over a period of 3 months with a total
of 6 L of saline. During the expansion process, there was
threatened erosion of the skin from the firm backing on the
rectangular abdominal expander, and it was replaced with a
smooth-walled expander. The twins were treated in a
Clinitron bed for the entire expansion period, thus
eliminating the problems with skin breakdown on the back.
However, continuous movement of the legs caused chronic
abrasion of the expanded skin overlying the tissue expander
in the tripus against the expanded abdominal skin, and
therefore, the legs were immobilized in a cast. Separation
was successful with sufficient soft tissue to cover both twins
without sacrifice of the tripus.
Case 6  Thoracopagus and omphalopagus twins (1999)
This thoracopagus and omphalopagus twin pair were
separated at 6 months of age. They were joined from the
level of the manubrium to the umbilicus with a shared liver,
diaphragm, and chest cavity, although their hearts were not
joined (Fig. 42.13). At 3 months of age, three rectangular-
shaped 500 cc remote port tissue expanders were placed, one
superior to the area of union in the thoracic area, and the
other two at the inferior lateral aspect of the junction in the
lower abdomen. These were filled over the next 3 months
and produced ample expanded skin. At the time of
separation, Gore-Tex patches were used by the general
surgeons to close the chest cavities in both twins; there was
sufficient soft tissue for uneventful and stable closure over
these prostheses.

937
Treatment/surgical technique
Fig. 42.14  (A) Ischiopagus twins with shared liver and colon, with tissue
expanders in place. The shared colostomy is visible. (B) Twin A with complete skin
closure of abdominal wall.
A
B
B
(B) A 3D computed tomography scan was helpful in
demonstrating shared skeletal structures.
Fig. 42.13, cont’d
Case 7  Ischiopagus twins (2001)
This ischiopagus twin pair were separated at 7 months of
age. They had joined livers, a shared colon, and both had a
cloacal malformation requiring a shared colostomy shortly
after birth. Four expanders originally were placed in the
thoracic and abdominal regions at 3 months of age (Fig.
42.14A). The patients were taken back to the operating room
twice during the expansion process because of expander
complications. The thoracic expander was removed due to
some overlying skin necrosis and one of the lateral
abdominal expanders was removed due to threatened
exposure and a seroma. One month later, two additional
expanders were placed in the thoracic and abdominal
regions since a greater soft-tissue requirement was
anticipated. Expansion was resumed uneventfully, and
separation was performed 3 months later. Vicryl mesh was
used in closure of the abdominal wall due to contamination
from the colostomy during the procedure with a plan for
more definitive abdominal wall reconstruction in the future.
Local advancement and rotation flaps of the expanded
thoracic and abdominal skin were used and complete
coverage of the abdominal defect was obtained in one twin.
In the second twin, a small lateral defect remained after
rotation of the abdominal skin flap; vacuum-assisted closure
therapy hastened wound healing, and the defect was
eventually covered with an autologous skin graft (Fig. 42.14B).
Case 8  Omphalopagus twins (2007)
This pair shared a portion of liver and duodenum. Four
expanders were placed in subcutaneous pockets, but one
developed a leak during the expansion process. Acellular
dermal matrix was used to compensate for insufficient skin
coverage over the central abdomen (Fig. 42.15).

938
SECTION III
CHAPTER 42 • Conjoined twins
Case 9  Thoracopagus and omphalopagus twins (2011)
This complex pair were fused from chest to abdomen
including conjoined pericardium, diaphragm,
communicating cardiac structure, long segment jejunum,
and biliary tree. One of the twins required cardiac surgical
intervention through a right thoracotomy at 2 months of age
due to a hypoplastic right ventricle and pulmonary stenosis.
Four expanders were placed at 3.5 months and separation
occurred at 8 months of age. Thoracoplasty was performed
in one twin to reposition the ribs and partial manubrium,
then Gore-Tex patches were used in both twins to complete
chest closure. After complex hepatobiliary and intestinal
reconstruction, the large abdominal defects in both twins
were closed with absorbable Vicryl mesh followed by Strattice
porcine dermal matrix. Despite aggressive mobilization of
the skin flap, defects remained which were treated with
vacuum-assisted sponge devices. In one twin, the area was
granulated and re-epithelialized without the need for skin
grafting. The second twin with the hypoplastic right heart
suffered a complicated postoperative cardiac and respiratory
course, with eventual demise 8 months post-separation.
Case 10  Thoracopagus and omphalopagus twins (2012)
This pair shared pericardium, diaphragm, and liver. At 3
months of age, four tissue expanders were placed on the
lateral chest and abdominal walls adjacent to the central
conjoined area, with care taken to avoid trauma to the breast
bud, and 5 months later, the twins were separated
successfully. Large chest and abdominal wall defects with
exposed heart and areas of the liver, diaphragm, and
intestines in both twins were reconstructed with Vicryl
Postoperative care
Supportive care in an intensive care unit setting with meticu­
lous monitoring is essential for postoperative stabilization of
the separated infants. Elective paralysis and ventilation for
24–48 h are preferable during the immediate postoperative
period for fluid and electrolyte replacement and cardiac sta­
bilization. Perioperative antibiotics and strict infectious pre­
cautions are also recommended to avoid sepsis.
Perioperative pressure reduction strategies are critical for
successful management of the soft tissues. A Clinitron bed is
recommended during tissue expansion to optimize soft-tissue
viability and prevent pressure-related ulcerations in depen­
dent areas or over the expanders. This should be continued
during the early postoperative period of immobilization to
augment postoperative wound healing, especially when flaps
and grafts have been utilized in closure. Adjunctive techniques
such as frequent turning, supportive gel padding, and immo­
bilization of the extremities when necessary to prevent trau­
matic ulcerations, should also be employed.
Continued nutritional support is equally critical. More
often than not, one of the infants is smaller and less well
nourished. The stress of prolonged treatment and repeated
operations compounds this problem, placing the infants at
greater risk for wound-healing and infectious complications.
In this situation, the use of supplemental parenteral or enteral
feedings is beneficial, and should be considered in most cases.
Outcomes, prognosis,
and complications
Wound-healing complications are common postoperatively.
Postoperative vacuum-assisted closure therapy can be useful
in managing wound dehiscence or flap losses, and secondary
skin grafting and surgical revision are frequently necessary to
manage soft-tissue wounds and unacceptable scarring.
The overall success of conjoined twin separation depends
on the experience and preparedness of the treating team and
the resources available at the pediatric specialty center. Recent
advances in imaging techniques for prenatal diagnosis, pre-
and postoperative critical care management, and anesthetic
care have improved outcomes and survival rates in general.
Comprehensive long-term care by a multispecialty team is
critical in the management of these patients from prenatal
diagnosis to postoperative follow-up to address their complex
issues. Follow-up at the same institution is recommended due
to the anatomic complexity of these patients, and it also allows
for determination of long-term outcomes.
Fig. 42.15  Omphalopagus twins with newly placed expanders. The injection ports
are dorsally located. Two additional expanders were placed on the contralateral side.
absorbable mesh covered by Strattice porcine dermal matrix
and expanded skin. One twin developed a partial wound
dehiscence with exposed Strattice. After slow secondary
healing, this site developed a ventral hernia, which was
successfully repaired at age 2 years with permanent mesh.

939
Outcomes, prognosis, and complications
1. Bates AW. Conjoined twins in the 16th century. Twin Res. 2002;5:
521–528.
3. Redett R, Zucker RM. Conjoined twins. In: Bentz M, Bauer BS,
Zucker RM, eds. Principles and Practice of Pediatric Plastic Surgery. St.
Louis: Quality Medical Publishing; 2008:185–212. A well-rounded
account of perioperative and operative considerations relating to the
separation of conjoined twins is presented.
5. Spitz L. Surgery for conjoined twins. Ann R Coll Surg Engl.
2003;85:230–235.
6. Spitz L, Kiely EM. Conjoined twins. JAMA. 2003;289:1307–1310. The
authors begin with an account of conjoined twin reports in history. A
review of classification, diagnosis, and management follows.
10. Spitz L. Conjoined twins. Br J Surg. 1996;83:1028–1030. This brief
reports offers the author’s perspective from an experience of 10 sets of
conjoined twins over a decade. Special mention is made of the potential for
heavy intraoperative blood loss and the fragility of these patients after
separation.
12. O’Neill JA Jr. Conjoined twins. In: Grosfeld JL, O’Neill JA Jr,
Fonkalsrud EW, et al., eds. Pediatric Surgery. Philadelphia: Mosby;
2006 This chapter is a review of topics ranging from prenatal diagnosis to
ethical considerations related to conjoined twins. Particularly useful is the
authors’ systems-based approach to surgical technique.
14. Mackenzie TC, Crombleholme TM, Johnson MP, et al. The natural
history of prenatally diagnosed conjoined twins. J Pediatr Surg.
2002;37:303–309.
21. Walker M, Browd SR. Craniopagus twins: embryology,
classification, surgical anatomy, and separation. Childs Nerv Syst.
2004;20:554–566.
28. Spencer R. Theoretical and analytical embryology of conjoined
twins: part I: embryogenesis. Clin Anat. 2000;13:36–53. This review
spans over 1200 cases of conjoined twins. Observations drawn from these
cases form the basis for a discussion of the embryology leading to this
pathology.
41. Zubowicz VN, Ricketts R. Use of skin expansion in separation of
conjoined twins. Ann Plast Surg. 1988;20:272–276.
Access the complete reference list online at

939.e1
References
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account of perioperative and operative considerations relating to the
separation of conjoined twins is presented.
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authors begin with an account of conjoined twin reports in history. A
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tissue fluorescein delivery and prediction of flap viability with the
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41. Zubowicz VN, Ricketts R. Use of skin expansion in separation of
conjoined twins. Ann Plast Surg. 1988;20:272–276.
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45. Dasgupta R, Wales PW, Zuker RM, et al. The use of Surgisis for
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46. Burns NK, Jaffari MV, Rios CN, et al. Noncross-linked porcine
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47. Gupta A, Zahriya K, Mullens PL, et al. Ventral herniorrhaphy:
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CHAPTER 42 • Conjoined twins
particular reference to quality of life. J Pediatr Surg. 1993;28:
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preserved skin autografts. Surgery. 1964;56:742–746.

SECTION III • Pediatrics
43 
Reconstruction of urogenital
defects: Congenital
Mohan S. Gundeti, Michael C. Large, and William R. Boysen
SYNOPSIS
■ Hypospadias is common, perhaps increasing in incidence, and may be
managed through multiple surgical approaches. Penoscrotal
transposition and chordee commonly accompany hypospadias and
may be treated concomitantly.
■ Reconstruction of cloacal or urogenital sinus abnormalities is complex,
often requiring multiple surgical disciplines and stages to obtain
optimal functional outcomes. Timing of reconstruction for ambiguous
genitalia remains controversial, but advancement in knowledge of the
neuroanatomic innervation has allowed for reconstruction with good
preservation of function.
■ Technique for repair of bladder and cloacal exstrophy continues to
evolve, with debate over single versus staged repair.
Introduction
The reconstructive techniques for congenital urogenital defects
are broad ranging, and the indications for intervention vary
from emergent to elective. Herein the authors will discuss
the normal development of the urogenital tract, followed by
a discussion of some common female and male disorders and
their surgical repairs. The spectrum of hypospadias disorders
will be addressed first, followed by cloacal and urogenital
sinus disorders, and a brief discussion of variant presentations
that may include clitoromegaly, exstrophy, and/or epispadias.
For each condition, attention will be given to diagnosis and
evaluation, representative surgical techniques, potential com­
plications, and expected short-term and long-term outcomes.
In general, reconstructive techniques for urologic disorders
have satisfactory outcomes, but the importance of proper
surgical timing and patient selection may not be understated.
Normal development
The cloaca appears during the 2nd gestational week, with the
urorectal septum forming during week 4 (Fig. 43.1). The
urorectal septum fuses with the cloacal membrane by week 7.
Defects of the cloacal membrane may result in bladder or
cloacal exstrophy and epispadias. The Mullerian ducts fuse to
become the uterovaginal canal. Distally, the urogenital sinus
forms the vestibule and the intervening sinovaginal bulbs
canalize to form the distal vaginal canal. Paramesonephric
abnormalities are frequently associated with ipsilateral renal
anomalies, partly based upon their proximity during develop­
ment. Anomalies of agenesis and fusion may occur. When the
urogenital sinus fails to develop into the distal vagina, atresia
results; agenesis occurs when the proximal third of the vagina
fails to develop in a 46XX phenotypic female. Transverse septa
arise from failure of fusion or canalization of the urogenital
sinus and Mullerian ducts. Mayer–Rokitansky–Kuster–Hauser
syndrome consists of Mullerian aplasia, often accompanied
by renal and cervicothoracic dysplasias.
Differentiation of the external genitalia begins around 7–8
weeks’ gestation. The male gonads differentiate secondary to
the transcription of the SRY gene, thereby producing testos­
terone. The distance between anus and genitalia increases, the
phallus elongates, the genital folds fuse, the preputial folds
form and fuse dorsally, and during the 11th gestational week,
the urethral folds fuse ventrally. If the genital folds fail to fuse,
as in hypospadias, the preputial folds also fail to fuse ventrally,
resulting in excessive dorsal preputial tissue. By week 16, the
glandular urethra forms. The glandular portion of the urethra
is lined by squamous epithelium, which likely also arises from
urogenital sinus origin, but then undergoes differentiation.1
Histologically, the hypospadiac urethral plate contains sinu­
soids of urethral spongiosum and no scar tissue. The innerva­
tion of the hypospadiac penis is like that of the normal penis:
the pudendal nerve gives off the dorsal nerve, which travels
as two bundles on either side of 12 o’clock.
In females, the folds of the urogenital sinus remain open
and become the labia majora, the labioscrotal folds form the
labia minora, the genital tubercle becomes the clitoris, and the
urogenital sinus becomes the lower vagina and urethra. An
excess or absence of intrauterine androgens at 9–14 weeks can
alter this process, leading to ambiguous external genitalia.
Access video content for this chapter online at expertconsult.com

941
Normal development
Fig. 43.1  Development of the urogenital tract. (Modified from Larsen WJ. Human Embryology. New York: Churchill Livingstone; 1997.)
Genital ridge
development
Genital tubercle
Cloacal fold
Urogenital fold
Labioscrotal fold
Anus
8th week
12th week
12th week
7th-9th month
Testicular descent
into the scrotum
20th week
Testis
Ovary
Cloacal membrane
Paramesonephric
duct
Paramesonephric
duct
Sinovaginal bulb
Process
vaginalis
Testis
Gubernaculum
Uterus
Vagina
Hymen
Paramesonephric
(Mullerian) duct
Mesonephric
(Wolffian) duct
Prostate
Bulbourethral
gland
Seminal
vesicle
Formation
of sex cords
38
28
20
12
7
6
5
4
3
Weeks
Migration of primordial germ cells
Gonadal differentiation
10th-12th weeks
10th-12th weeks
Development of
external genitalia

942
SECTION III
CHAPTER 43 • Reconstruction of urogenital defects: Congenital
43.3). The more severe the hypospadias, the more likely it is
accompanied by chordee and penoscrotal transposition (Figs.
43.4 & 43.5).
The incidence of hypospadias is roughly 1 : 300 male births,
an increase from 2 : 1000 male births in 1970. There is nearly a
nine-fold increase in hypospadias in monozygotic twins. A
polygenic, multifactorial etiology is most likely. Some cases
may be caused by testosterone, dihydrotestosterone, or andro­
gen receptor deficiencies, but these are found in only 5% of
cases. There are also hypotheses that maternal environmental
exposures such as phthalate in some plastics and estrogens in
food, cosmetics, and pesticides can increase the risk of hypo­
spadias, though there is not definitive evidence to support
this. Theories of chordee include incomplete development of
the urethral plate, abnormal urethral meatal mesenchyme,
and disproportional corporal growth.
Hypospadias is frequently diagnosed at birth on physical
examination, although later diagnoses are not uncommon.
Patients with bilateral impalpable gonads and hypospadias
have a disorder of sexual differentiation until proven other­
wise, and karyotype is indicated.
Patient selection is most pertinent to hypospadias repair.
The meatal location, glans volume, penile length, presence of
penoscrotal transposition and/or chordee, and width and
depth of the urethral plate all weigh in the surgeon’s selection
of technique. In general, distal hypospadias with favorable
features may be treated by tubularized incised plate (TIP)
procedure with meatoplasty and glanuloplasty (MAGPI)
techniques, while proximal hypospadias are frequently
treated by two-staged graft or onlay island flap repairs.
The optimal timing for hypospadias repair is 6 months of
age in a full-term male, allowing the glans and phallus to
grow during the testosterone surge that occurs naturally
between 4 and 6 months of age. Some 92% of pediatric urolo­
gists perform a TIP procedure for distal hypospadias.2 Proxi­
mal hypospadias without curvature is repaired by TIP or
onlay island flap by equal proportions of urologists, while
proximal hypospadias with severe chordee is most often
repaired by a staged repair.3 Intramuscular testosterone injec­
tions of 25 mg/dose or 2 mg/kg per dose may be administered
up to three times prior to repair, in an attempt to improve
penile vascularity and tissue robustness, thereby facilitating
subsequent surgery. However, studies assessing the effect of
The clitoral innervation travels along the dorsal surface of the
clitoris before entering the corporal tissue, and care must be
taken not to dissect or mobilize this area during reconstruc­
tion to preserve innervation and future sexual function.
Hypospadias
Background, diagnosis, and patient selection
Hypospadias occurs when the development of the urethral
spongiosum and prepuce halts, resulting in a meatal location
proximal to that of the distal glans. A hypospadiac meatus
is often accompanied by penile chordee as the normal
embryologic correction of curvature is arrested. The severity
of hypospadias is dictated by associated chordee, urethral
plate width, glans volume, phallus size, and meatal loca­
tion, which can range from perineal to glanular (Figs. 43.2 &
Fig. 43.2  Spectrum of hypospadias. (Reproduced from Wein AJ, et al. Campbell-
Walsh Urology, 9th edn. Philadelphia: Saunders; 2007.)
Glanular
Coronal
Anterior
Middle
Posterior
Subcoronal
Distal
penile
Proximal
penile
Penoscrotal
Scrotal
Perineal
Anus
Midshaft
Fig. 43.3  (A) Glanular, (B) coronal, (C) penoscrotal, and (D) perineal hypospadias.
A
B
C
D

943
Hypospadias
Meatoplasty and glanuloplasty
The MAGPI repair is best suited for the individual with a
distal or anterior hypospadias. Often, these patients are able
to void with a straight stream, but the repair is requested for
social, cultural, or parental concerns. The initial incision is
circumferential, 5 mm proximal to the glans, and degloving
is performed, allowing for orthoplasty (Fig. 43.7). Any bridge
within the urethral plate is incised and then repaired in
Heineke–Mikulicz fashion so that the distal glanular groove
and the more proximal hypospadiac meatus are in continuity.
A stay stitch allows for distal advancement of the meatus, and
the glans edges are subsequently trimmed and approximated
in two-layer fashion.
Tubularized incised plate repair
For all distal variants of hypospadias, it is recommended that
surgeons choose a single technique that allows for reproduc­
ible outcomes with 95% success rates. Easily reproducible, the
TIP repair is the authors’ initial choice for patients with distal
hypospadias. The urethral plate is measured in width, and
diluted epinephrine may be injected prior to incision (though
this is not the authors’ practice). A vertical incision is made
alongside each edge of the urethral plate, and a crossing incision
connects the two at the proximal extent of the meatus. The depth
of the lateral incisions is based upon the glans volume and plate
size; the crossing incision should be exceptionally thin, serving
simply to disconnect the ventral penile skin from the underlying
urethra, while avoiding entrance into the urethral lumen (Fig.
43.8). Similar to the MAGPI repair, a circumferential incision
extends each side from the crossing incision, approximately
5 mm from the coronal margin. The penis is degloved, chordee
is assessed, and orthoplasty is performed if indicated. The
midline of the plate is then incised utilizing an ultrafine-tipped
preoperative testosterone on postoperative complication rate
have yielded mixed results, leaving the role of preoperative
hormone stimulation unclear.4 In the authors’ experience,
there is a role for preoperative testosterone in patients with
unfavorable preoperative factors such as small glans size and
narrow urethral plate. Outcomes for these patients will likely
be impacted by many factors in addition to preoperative
testosterone, including surgical technique.
Treatment/surgical technique
The goal of hypospadias repair is to allow for standing uri­
nation and normal ejaculatory function, while providing a
slit-like terminal meatus. The technique should be simplistic
with readily reproducible results. The prepuce may or may
not be reconstructed depending upon cultural and patient
expectations. Scrotoplasty may be performed for significant
penoscrotal transposition (Fig. 43.6). Baskin and Ebbers
delineate five steps apparent in all hypospadias repairs: ortho­
plasty (straightening of the penis), urethroplasty, meato- and
glanuloplasty, scrotoplasty, and epithelial coverage.5 Herein
the authors will highlight some of the more common repair
techniques.
Fig. 43.4  Intraoperative depiction of chordee.
Fig. 43.5  (A,B) Penoscrotal transposition.
A
B
Fig. 43.6  Penoscrotal transposition correction. (Reproduced from Wein AJ, et al.
Campbell-Walsh Urology, 9th edn. Philadelphia: Saunders. 2007.)
Release of
scrotum
Approximation
of scrotum
Dorsal hooded
foreskin

944
SECTION III
CHAPTER 43 • Reconstruction of urogenital defects: Congenital
harvested and rotated to the ventrum along its pedicle. A
second layer of vascularized inner preputial tissue may be
utilized for coverage before glans approximation and closure.
The authors have rarely used this technique, as they prefer
either the TIP or two-stage repair when TIP is not feasible.
ophthalmologic knife, and the plate is tubularized around a
5 or 8 French feeding tube, which serves as a urethral stent.
Glans flaps are created laterally, making sure the tissue is
thick enough to provide food coverage and a tension free
closure. A second layer of dartos tissue or spongiosal tissue
is rotated to cover the urethral suture line. The glans is reap­
proximated in two layers, and the shaft is closed at midline
to complete the repair. In the case of a very shallow urethral
groove or small glans, a free graft may be interposed between
the posterior TIP defect, thereby allowing for larger ultimate
circumference.6
Onlay island flap repair
Onlay island flap repair is commonly employed for midshaft
hypospadias defects, although distal applications also exist.7
Two stay stitches are placed at corners of the prepuce (Fig.
43.9). Similar to a TIP repair, U-shaped and circumferential
subcoronal incisions are performed. Degloving and ortho­
plasty follow, after which the distance from meatus to distal
glans tip is measured. A rectangular preputial onlay graft is
Fig. 43.7  (A–F) Meatoplasty and glanuloplasty (MAGPI) for distal hypospadias defects. (Reprinted from Duckett JW. Hypospadias. In: Walsh PC, Retik AB, Vaughan ED Jr,
Wein AJ (eds). Campbell’s Urology, 7th edn. Philadelphia, WB Saunders; 1998.)
Urethral
meatus
A
Urethral
pit
B
C
D
E
Neomeatus
F
Hints and tips
• A glans traction suture helps with intraoperative
manipulation of the penis
• Placement of a penile tourniquet aids in visualization and
can be safely used for 45 min without compromising
outcomes (in the authors’ experience)
• Minimization of tissue handling and creation of tension-free
anastomoses optimize tissue health
• Bipolar electrocautery forceps are preferable to monopolar
forceps for hemostasis
• A 2.5× or greater loupes or the surgical microscope may
improve tissue manipulation

945
Hypospadias
Fig. 43.8  (A–G) Tubularized incised plate (TIP) repair for hypospadias defects. (Reprinted from Retik AB, Borer JG. Primary and reoperative hypospadias repair with the
Snodgrass technique. World J Urol. 1998;16:186.)
Urethral
meatus
A
Urethral
plate
B
C
Mobilization of urethral plate
Incision of
urethral plate
D
E
New urethra formation
F
Second layer Dartos flap
G
Completed repair

946
SECTION III
CHAPTER 43 • Reconstruction of urogenital defects: Congenital
Urethral meatus
A
Preputial
skin
B
C
D
E
Glans
approximation
F
Fig. 43.9  (A–H) Onlay island flap repair for hypospadias defects. (Reprinted from Atala A, Retik AB. Hypospadias. In: Libertino JA (ed.). Reconstructive Urologic Surgery,
3rd edn. St. Louis: Mosby–Year Book; 1998.)
G
H

947
Ambiguous genitalia, persistent cloaca, and urogenital sinus disorders
Two-stage repair
For proximal hypospadias, a two-stage repair often affords
the greatest chance for long-term success, albeit with the limi­
tation of multiple surgeries separated by 6 months or more.
A subcoronal circumferential incision is made, as well as a
longitudinal incision from glans tip to hypospadiac meatus
(Figs. 43.10–43.12). Once the healthy urethral plate is identi­
fied, the remaining distal plate is excised. The glans is split
longitudinally, and the resulting urethral defect measured.
If of sufficient size, the prepuce may be utilized as either a
pedicled flap or free graft (Video 43.1
). If insufficient, a free
graft of buccal mucosa is performed with a 1 : 1 ratio of graft to
site sizing. The buccal tissue has an extensively vascularized
lamina propria, so long-term shrinkage is minimal. Second-
stage repair is performed by tubularization of the graft with
second-layer coverage before final epithelial approximation
(see Fig. 43.11 and Video 43.2
).
Orthoplasty
While discussion of chordee repair is contained elsewhere
(Vol. 4, Chapter 13), a brief description of the authors’ chosen
approach to orthoplasty will follow. After complete degloving
of the penis, <10% of patients with hypospadias require penile
straightening.8 A Gittes test is performed, during which a
penile tourniquet is tightened, and a small-gauge butterfly
needle is placed through the glans directly into one of the
corpora cavernosa. Sterile saline is slowly injected into the
corpus until an erection is achieved, and any chordee is elu­
cidated. As anatomic studies have shown, a paucity or absence
of neural structures at the 12 o’clock position of the penile
shaft, the authors repair all instances of chordee by simple
midline dorsal plication (Fig. 43.13) and no longer perform
historical, more elaborate techniques.5 The authors prefer
to avoid Nesbit corporal plication or corporal grafts due
to concerns for neuronal damage, erectile dysfunction, and
venous leak. However, long-term data on outcomes for these
techniques are lacking.
Postoperative care
Hypospadias repair is primarily an outpatient procedure.
Pain control is ameliorated by a preoperative caudal nerve
block. A soft 5 or 8 French feeding tube is utilized to stent the
urethra. A dressing consisting of three supportive DuoDerm
strips followed by a Tegaderm wrap serves to keep the penis
elevated, thereby minimizing swelling.
Hints and tips
• Glans-to-glans approximation is critical in preventing meatal
regression after meatoplasty and glanuloplasty (MAGPI)
repair
• After degloving and orthoplasty of the penis, an initially
distal hypospadias may now appear proximal and require a
more extensive repair. Similarly, in a patient with poor distal
urethral tissue, proximal dissection to healthy spongiosum
may convert a distal hypospadiac meatus to a proximal
defect
• Urinary diversion with catheter for 5–7 days is crucial for
optimizing outcomes
Complications and outcomes
The mantra of “the first chance being the best chance” is
certainly true for hypospadias repair. While successful out­
comes are the norm, those who have poor surgical outcomes
are at risk for scarring and abnormal-appearing genitalia,
difficulty in urinating, and long-term sexual and relationship
difficulties. Bleeding and catheter dislodgement are the most
common issues encountered immediately postoperatively.
A second layer of coverage is the single best measure for
preventing urethrocutaneous fistula formation. Less common
complications include meatal stenosis, infection, urethral
diverticula and stricture, and balanitis xerotica obliterans
(BXO). Diverticula, strictures, and BXO are more common
with two-stage repairs or those with replacement urethro­
plasty with buccal mucosal graft.
With regard to the MAGPI repair, Duckett and Snyder have
described 1000 patients with fistulae in 0.5%, meatal retraction
in 0.06%, and chordee in 0.1% at mean follow-up of 2 months.9
These results have failed to be reproduced, with other groups
noting that at 2 years nearly 15% had complete meatal regres­
sion.10 Data for the TIP repair are evolving. A multicenter
review of over 2000 patients suggested a complication rate of
9%.11 Fistulae occur in 5%, meatal stenosis in 2%, and glans
dehiscence in 5%.12
A large series of onlay island flap repairs shows a 6%
urethrocutaneous fistula and 9% reoperation rate.13 In a review
of 600 patients with two-stage repair, the majority preputial,
a first-stage revision was required in 4%, and second-stage
fistulae occurred in 6%, although the use of a dartos flap for
second-layer closure may serve to limit this rate further.14
Secondary procedures for hypospadias are sometimes
required in the event of primary failure. Distal or midshaft
hypospadias repairs should be single-staged and definitive.
When complications such as urethrocutaneous fistulae do
occur, primary repair, while attempted by some, is cautioned.
Our experience has echoed that of Bracka, where two-stage
buccal mucosa repair has yielded good results for those with
previous failed hypospadias repair.14
Data regarding long-term cosmesis, urinary function, and
sexual function remain quite limited, though this is an area of
ongoing study. Numerous validated outcome assessment
scales have been developed including the Penile Perception
Score15 and the Hypospadias Objective Penile Evaluation
(HOPE) score,16 which will hopefully facilitate future studies
assessing these outcomes among men who have undergone
hypospadias repair. Regardless of the assessment scale used,
the data on long-term outcomes are limited and mixed, with
some series reporting higher rates of sexual dysfunction
among men who have undergone hypospadias repair and
others showing no difference compared with matched con­
trols.17 As expected, severity of hypospadias prior to surgery
correlates with the degree of sexual dysfunction and dissatis­
faction with cosmetic result.18
Ambiguous genitalia, persistent cloaca,
and urogenital sinus disorders
Background, diagnosis, and work-up
Urogenital sinus abnormalities may be isolated or associated
with congenital adrenal hyperplasia (CAH), most often due

948
SECTION III
CHAPTER 43 • Reconstruction of urogenital defects: Congenital
A
B
C
D
E
Preputial flap
F
G
H
Fig. 43.10  (A–F) First stage of two-stage hypospadias
repair with preputial flap – vascularized. (G,H) The
authors’ technique for free preputial/buccal graft for
first-stage hypospadias repair.

949
Hypospadias
Quilting incisions
Buccal graft
I
J
K
L
M
(I–M) Second-stage
hypospadias repair of two-stage repair.
(Reprinted from Retik AB, Borer JG. Primary and
reoperative hypospadias repair with the
Snodgrass technique. World J Urol.
1998;16:186.)
Fig. 43.10, cont’d

950
SECTION III
CHAPTER 43 • Reconstruction of urogenital defects: Congenital
Fig. 43.11  (A,B) Harvesting the buccal mucosal graft. (C) Buccal mucosal onlay graft with catheter overlying.
A
B
C
to 21-hydroxylase deficiency. These conditions are rare, with
incidence of CAH approximately 1 : 5000–15 000, UG sinus
abnormality 0.6 : 10 000, and persistent cloaca 1 : 20 000.
The work-up of a newborn with ambiguous genitalia
should involve multidisciplinary teams and critical associa­
tions such as CAH should be ruled out. Fluid and electrolyte
balance and blood pressure control should be maintained.
Examination should note any suprapubic mass or ascites,
sacral dimples, genitalia curvature and size, palpability of
gonads, location of anus and perineal orifices, and pigmenta­
tion. Karyotype and adrenal biochemical studies should be
undertaken, with prompt replacement of cortisol and fludro­
cortisone in cases of congenital adrenal hyperplasia. In utero
exposure to androgenic substances should be investigated,
as should a family history of infantile death. Radiographic
and endoscopic evaluations of the genitalia and urinary tract
are indicated, including abdominal X-ray and ultrasound,
genitography, echocardiography, lumbar magnetic resonance
imaging (for patients with isolated cloacal malformation due
to association with VACTERL malformations), and cystoscopy
with vaginoscopy for planning approach to surgical repair.
The Prader classification system has classically been used
to describe urogenital sinus abnormalities, which can range
widely in severity and degree of feminine or masculine
appearance.19 An updated classification system has been
described to further delineate the spectrum of disorders that
exist, with attention paid to the phallic length/width and true
vaginal location in addition to the external appearance
described by Prader.20 The clinical utility of this updated clas­
sification system remains unclear.
Treatment/surgical technique
The optimal timing of surgical repair remains controversial,
and consideration must be made to the child’s long-term
psychosexual development and gender satisfaction.21 Consul­
tation with an experienced multidisciplinary team is recom­
mended prior to surgery. In particular, a pediatric surgeon
with experience in gastrointestinal surgery is needed for the
anorectoplasty component of cloacal repair.
Abnormalities of the urogenital sinus may be divided into
low or high confluence defects. A confluence of the urogenital
sinus distal to the urinary sphincter is considered low; those
proximal are high. Common channel length of 3 cm is also
used to differentiate low and high confluence defects. Goals
of feminizing genitoplasty should include creation of normal
appearing external female genitalia, creation of an unob­
structed urinary tract free of incontinence and recurrent
infection, and allowance of normal adult reproductive and
sexual function.22 Repair may involve nerve sparing reduction
clitoroplasty, development of labial folds, and construction of
a capacious vagina. The perineal approach is commonly
preferred except in high variant cases, where prone position­
ing is preferred initially.
Lower confluences may be repaired by cut-back vagino­
plasty for simple labial adhesions, flap vaginoplasty, or
vaginal pull-through. In a flap vaginoplasty, a posterior peri­
neal flap is fashioned anterior to the rectum (Fig. 43.14). The
posterior urogenital sinus wall is incised and subsequently
sutured to either side of the interposing posterior skin flap.
The anterior vaginal wall remains intact.

951
Ambiguous genitalia, persistent cloaca, and urogenital sinus disorders
A
B
C
D
Fig. 43.12  Two-stage hypospadias repair with chordee correction. (A) Perineal hypospadias; (B) chordee; (C) corrected chordee; (D) completed first-stage repair 6 months
postoperatively;
Continued

952
SECTION III
CHAPTER 43 • Reconstruction of urogenital defects: Congenital
For some low and all high confluence sinuses, total
urogenital mobilization may be indicated with subsequent
pull-through vaginoplasty. Partial urogenital mobilization has
also been described and can be considered in cases where
adequate mobilization is achieved without dissection under
the pubic bone and up to the bladder neck. To perform
urogenital mobilization, the authors prefer the technique
described by Rink and Cain.23 With the child in the lithotomy
position, cystoscopy and vaginoscopy is performed to
assess the common channel. A Fogarty catheter is placed in
the vagina and a Foley catheter in the bladder to facilitate
manipulation as needed. The child is then returned to the
supine position and a traction suture is placed through the
clitoris. Clitoroplasty, described below, can be performed at
this time if desired. To begin total urogenital mobilization,
the sinus is dissected circumferentially. The dissection is
carried to the pubourethral ligament anteriorly behind the
pubic bone and posterior to the vagina, to allow mobilization
of the entire urogenital complex down to the perineum. In
partial urogenital mobilization, the dissection is stopped
at the pubourethral ligament. The urogenital sinus is then
dissected from the corporal bodies. Traction sutures can be
placed around the sinus meatus to aid in exposure. An omega
flap is then raised posteriorly to expose the posterior aspect
of the UG sinus. The posterior dissection can be challenging,
and care must be taken to avoid injury to the rectum or entry
into the UG sinus. Next, the posterior wall of the vagina is
opened over the Fogarty catheter between stay sutures. If a
tension-free anastomosis to the perineum cannot be achieved
without further mobilization, then total urogenital mobiliza­
tion must be performed with additional dissection anteriorly
behind the pubic bone followed by pull-through vaginoplasty.
Interrupted absorbable sutures are used to approximate the
vagina to the perineal skin flap or to the distal redundant sinus
membrane rotated to bridge any gap between vaginal ostium
and skin.
F
G
E
(E–G) second-stage
hypospadias repair depicting free preputial
and delayed tubularization. (H) The final
appearance 1 year after the second-stage
repair.
Fig. 43.12, cont’d
H

953
Exstrophy–epispadias complex
unobstructed urinary tract free of incontinence and recurrent
infection, and allowance of normal adult reproductive and
sexual function/sensation. One series reviewed outcomes of
22 girls undergoing total urogenital mobilization for cloaca
repair, with complications including urethral stenosis (9%),
urethrovaginal fistula (4.5%), residual common channel
requiring urethral revision (4.5%), and a need to re-do poste­
rior sagittal anorectoplasty for complete vaginal and anal
closure (4.5%).27 Another small series of seven patients under­
going total urogenital mobilization demonstrated a postop­
erative continence rate of 86%, with half of those patients
voiding spontaneously and the other half requiring clean
intermittent catheterization. In this same small study of seven
patients, urodynamic studies showed detrusor underactivity
or acontractility, with normal compliance in 86% of patients
and poor compliance in the remaining 14%.28 With respect to
urinary continence, another series has demonstrated that
there is no significant difference in rates of continence between
children undergoing total urogenital mobilization versus
partial urogenital mobilization. They report an overall conti­
nence rate of 95.5% by 3 years of age, regardless of surgical
approach. Continence rates are slightly lower in children
undergoing urogenital mobilization for persistent cloaca
(87.5% at 3 years of age) compared with those with persistent
urogenital sinus (96.4% continent at age 3 years).29
Genetic, social, hormonal, and psychological factors all
impact sexual outcomes. Long-term data on sexual outcomes
are limited but preliminary studies do suggest that, despite
efforts to preserve the neurovascular bundles during surgery,
sensation is markedly impaired in woman having undergone
feminizing genitoplasty relative to controls. One series identi­
fied 37 women with ambiguous genitalia, of which 24 had
undergone feminizing genitoplasty and 13 had not undergone
surgery. Rates of anorgasmia were higher among women who
had undergone surgery (26% vs 0%), but sexual function
scores based on a standardized questionnaire were not differ­
ent between the groups. Sexual function scores were signifi­
cantly lower among all women with ambiguous genitalia
regardless of surgical history relative to the overall popula­
tion, suggesting that the disease process itself may play a role
in the diminished sexual function and not surgery alone.30
Numerous other studies have examined this issue, but are
limited by small numbers and lack of standardized assess­
ment tools. Despite these limitations, it is clear that children
born with ambiguous genitalia tend to have diminished
sexual satisfaction and desire, though dyspareunia is rare.31
Exstrophy–epispadias complex
Background and diagnosis
Bladder exstrophy tends to occur in nulliparous, young
females’ offspring, with a recurrence risk of 1 : 275 and a risk
of 1 : 70 in progeny. Incidence is approximately 1 : 30 000 with
a male-to-female ratio of 3 : 1. Patients have a low-set umbili­
cus and wide pubic diastasis. The pubic bone is shortened by
30%, with external rotation of the posterior pelvis. The clitoris
or penis is short and bifid due to separation of the pubis, and
the urinary sphincter mechanism is underdeveloped. Nearly
all patients have radiographic evidence of vesicoureteral
reflux, and the incidence of inguinal hernias is increased. In
With regard to clitoroplasty, the glans clitoris, the tunics,
and the neurovascular bundles are preserved, while excess
erectile tissue may be left intact or debulked laterally.24 Salle
et al. advocate for corporal body preservation, while Poppas
et al. have demonstrated that debulking can be performed
without damaging the dorsal nerves or impacting clitoral
sensation.25,26 To begin, a U-flap is created anterior from
the perineum to each lateral ventral aspect of the phallus
(Fig. 43.15). A single incision connects the two flaps along
the perineal raphe. The phallus is then degloved, leaving the
ventral strip intact. Buck’s fascia is incised, and the caver­
nosa are separated from the tunics and suture-ligated. The
glans is then approximated to the ends of the foreshortened
cavernosa.
Fig. 43.13  Approach to chordee correction, showing suture placement at 12
o’clock to avoid neurovascular structures. (Reproduced from Baskin LS.
Hypospadias: anatomy, embryology, and reconstructive techniques. Braz J Urol.
2000;26:621.)
Hints and tips
• Endoscopic elucidation of the confluence is critical in
planning urogenital sinus repair (Fig. 43.16)
• Identification and preservation of the neurovascular bundles
are critical for successful clitoroplasty
• Total or partial urogenital mobilization without separation of
vagina from urethra allows for optimal outcomes
Complications and outcomes
As previously mentioned, the goals of surgery for persistent
urogenital sinus and persistent cloaca include creation of
normal appearing external female genitalia, creation of an

954
SECTION III
CHAPTER 43 • Reconstruction of urogenital defects: Congenital
Fig. 43.14  (A–C) Urogenital sinus repair. (Reproduced from Rink RC, Cain MP. Urogenital mobilization for urogenital sinus repair. Br J Urol Int. 2008;102:1182–1197.)
A
B
C

955
Exstrophy–epispadias complex
females, epispadias ranges in severity from simply a patulous
meatus to a complete dorsal separation of urethra and urinary
sphincter (Fig. 43.17). The clitoris may be bifid, the mons
shallow, and the labia minora underdeveloped. Repair often
involves tapering of the urethra with excision of dorsal redun­
dancy and subsequent genitoplasty (Fig. 43.18). The urethra
is reconstructed over a catheter, and the mons tissue is utilized
as a second layer for closure. In the Ransley–Gundeti modifi­
cation, the dorsal redundant tissue is excised, the posterior
urethral plate tubularized, and the anterior urogenital dia­
phragm reconstructed; however, additional sutures are placed
to anchor the distal urethra to the reconstructed urogenital
diaphragm (see Fig. 43.18). This modification is thought to
recreate more readily the physiologic anterior angulation of
the distal female urethra.
Treatment/surgical technique
Patients presenting with the exstrophy–epispadias complex
are managed with a staged procedure.32 Plastic cling film
or Tegaderm is utilized to keep the bladder mucosa moist
between birth and repair. In the neonatal period, bladder and
abdominal closure is performed similar to that for second-
stage cloacal exstrophy repair and is combined with bilateral
osteotomies (Fig. 43.19). Epispadias repair occurs 6–12
Fig. 43.15  (A–D) Corresponding
intraoperative sequence of urogenital sinus
repair with feminizing genitoplasty.
A
B
C
D
Fig. 43.16  Endoscopic view within common channel of urogenital sinus
demonstrating urethral (ventral) and vaginal (dorsal) orifices.

956
SECTION III
CHAPTER 43 • Reconstruction of urogenital defects: Congenital
normal social integration.34,35 These children require close
follow-up and may need additional surgery in the future
including bladder augmentation or revision of repair.
Vaginal agenesis
Background and diagnosis
Vaginal agenesis occurs in 1 : 5000 female births and is associ­
ated with Mayer–Rokitansky–Kuster–Hauser syndrome,
wherein the proximal two-thirds of the vagina is absent. A
mesonephric duct abnormality has been proposed as the
etiology, with diagnosis often occurring in the work-up of
primary amenorrhea.
For the patient with vaginal agenesis, the techniques and
timing of surgery remain controversial. It is apparent that the
majority of patients undergoing vaginoplasty as infants
require additional vaginal surgery. When vaginal defects are
associated with clitoromegaly, as in congenital adrenal hyper­
plasia, the surgeon has two fundamental options: perform an
uncomplicated clitoroplasty with deferred vaginoplasty or a
complex clitorovaginoplasty with deferred minor introitus
repair in postpuberty.
months later, and bladder neck reconstruction with ureteral
reimplantation and possible bladder augmentation in another
4–5 years if indicated. Complete primary repair of bladder
exstrophy has been described in recent years, but the authors
favor the staged approach. (For a more complete description,
please see Vol. 4, Chapter 13.)
Complications and outcomes
Important goals in managing exstrophy are urinary conti­
nence, sexual function, and aesthetic appearance, which often
require multiple procedures to achieve. Compared with the
staged repair, the one-stage repair has a high incidence of loss
of the glans or corpora, though the exact incidence of this
complication is unknown. One series of 48 patients undergo­
ing staged repair for bladder exstrophy demonstrated a con­
tinence rate of 90%, though 70% of patients did require
bladder augmentation to achieve continence. Only a third of
patients achieved continence with bladder neck reconstruc­
tion alone.33 Data on long-term outcomes are lacking, but
small series suggest men who undergo repair of bladder
exstrophy assess their own genital appearance as good or fair
in 71% of cases, have a normal sperm count in 63% of cases,
are able to achieve orgasm in 75% of cases, and tend to have
Fig. 43.17  (A) Ransley–Gundeti technique of female epispadias repair. (B) Female epispadias: triangulated area of excess diamond-shaped skin. (C) Urethral plate
mobilization. (D) Neourethra formation. (E) Pelvic floor tissue approximation over the neourethra. (F) Completed female epispadias urethral reconstruction, showing the
urethral angulation technique.
A
B
C
D
E
F

957
Vaginal agenesis
Fig. 43.18  Schematic of female epispadias repair. (Reproduced from Wein AJ, et al. Campbell-Walsh Urology, 9th edn. Philadelphia: Saunders; 2007.)
Hemiclitoris
Hemiclitoris
Labia minora
Labia minora
Vagina
Redundant tissue
is removed
Medial aspect of
labia minora and
hemiclitoris denuded
1st layer closure
Neourethra
sutured
Urethral mucosa
Bladder neck
Approximation
of clitoral hood
Approximation
of hemiclitoris
and labia minora
2nd layer
of closure
Subcuticular
skin closure
A
B
C
D
E
F
G
H
I
J
K

958
SECTION III
CHAPTER 43 • Reconstruction of urogenital defects: Congenital
Within bowel constructs, stenosis occurs more often with
the ileum than with the colon.42 The type of bowel utilized
depends upon surgeon preference and patient anatomy (e.g.,
cloacal exstrophy will require ileal vaginoplasty). Some advo­
cate the usage of sigmoid colon as the proximity of its mes­
entery allows for free passage into the low pelvis.43 Vaginal
reconstruction is cautioned in patients with cervical agenesis,
as severe ascending bacterial infections can result.
The neovaginal walls can also be formed by partial-
thickness skin grafts harvested from the hip and buttock,
though this is not as commonly performed in current practice.
Vulvobulbocavernosus, gracilis, or rectus myocutaneous flaps
are frequently utilized for vaginal reconstruction in the adult
population following radical pelvic surgery.
Non-operative management with serial dilation can also be
considered. Ideal candidates are highly motivated and compli­
ant, with a shallow vaginal dimple. Most patients treated with
dilation have good functional outcomes, as defined by ability
to satisfactorily achieve intercourse or accommodate largest
dilator without pain. Reported disadvantages include insuf­
ficient vaginal lubrication, decreased frequency of orgasm,
and rarely dyspareunia.44
Treatment/surgical technique
Reconstruction may involve grafts of the skin, intestine, or
buccal mucosa. Buccal mucosal vaginoplasty has been
reported with good success and durability.36,37 The buccal
mucosa grafts may be quilted, and after development of the
neovaginal space, single or multiple grafts are utilized to line
the cavity. A stent or mold is placed following suturing of the
graft to the vaginal bed. Others advocate usage of minced
0.5 mm2 micromucosal grafts derived mechanically from
bilateral buccal grafts.38 These micromucosal grafts are spread
onto five gelatin strips, each 2.5 × 6 cm2, to line the anterior,
posterior, apical, and lateral walls with a 5 mm interpatch
distance. Similarly, a silicone vaginal stent with drainage
holes and luminal packing is placed to maintain counterpres­
sure. Regardless of technique, the surgeon must place tanta­
mount importance on patient compliance as disuse or failure
to dilate may result in atrophy. It is the authors’ practice that
vaginoplasty is best performed once the patient is considering
sexual activity or of appropriate age for performing periodic
manual dilations.
The use of bowel results in mucus production, which may
require daily douching and result in odor or ulcerations.39
While bowel preparation has historically been advised, the
authors have found it to be unnecessary.40,41 A Pfannenstiel
incision is appropriate, although a midline incision may also
be employed. A 10 cm segment of mobile sigmoid or ileum
may be taken out of continuity and anastomosed directly to
the skin dimple (Fig. 43.20). While some surgeons detubular­
ize and subsequently fold the bowel to form the neovagina,
the authors find this unnecessary and perform a simple
proximal-limb closure with 2-0 absorbable suture. The distal
aspect of the bowel limb is anastomosed in recessed fashion
to skin flaps or the rudimentary vagina is cases of proximal
atresia. The bowel anastomosis may be hand-sewn or stapled.
With recent adoption of minimally invasive surgery among
pediatric patients, this can be undertaken with robotic assisted
laparoscopic approach.
Fig. 43.19  (A,B) Female bladder exstrophy repair. (C) Final late appearance.
A
B
C
Hints and tips
• The proximal extent of the bowel vaginoplasty limb may be
sutured to the sacrum or paraspinous ligaments to
minimize potential prolapse43
• For buccal mucosal repairs, each cheek may yield a graft
of approximately 3 × 7 cm. The graft should be harvested
from inside the vermillion border extending posterior, inferior
to Stensen’s duct
Complications and outcomes
Potential problems after vaginoplasty may include graft
foreshortening, injury to adjacent urinary structures, and

959
Vaginal agenesis
Fig. 43.20  (A,B) Myocutaneous flap vaginoplasty. Schematic depiction of bowel vaginoplasty: (C) colovaginoplasty and (D) ileovaginoplasty.
A
B
Neovaginal introitus
Myocutaneous flap
Vascular pedicle
C
Neovaginal introitus
Colovagina
Colon
Vascular pedicle
D
Colon
Neovaginal introitus
Vascular pedicle
Ileovagina

960
SECTION III
CHAPTER 43 • Reconstruction of urogenital defects: Congenital
problems secondary to prolonged postoperative immobiliza­
tion. Long-term studies on outcomes and complications are
limited by the rarity of conditions requiring vaginoplasty.
Stenosis or stricture of the intestinal segment can occur, and
is typically managed by dilation. Delaying vaginoplasty until
after puberty is associated with a lower overall complication
rate (56.8% pre-pubertal vs 14.8% post-pubertal), though
pre-pubertal vaginoplasty may be performed in children
undergoing other genital surgery or children experiencing
symptoms such as recurrent urinary tract infections or post-
void dribbling.45 A review of 57 patients who underwent
bowel replacement vaginoplasty demonstrated reasonable
sexual function, with 78% reporting sexual desire, 33%
reporting sexual arousal, 33% reporting sexual confidence,
and 78% reporting sexual satisfaction. Only 5% reported
dyspareunia.46
Conclusion
Congenital anomalies of the urogenital tract vary widely in
severity and incidence but generally result from failure of key
steps in normal embryogenesis. When any reconstructive
procedure is being considered, careful thought should be
given to the timing of surgery and the potential need for a
multidisciplinary approach. Outcomes tend to be quite good
overall, although long-term data are lacking due to the rarity
of these conditions.
4. Snodgrass W, Bush N. Recent advances in understanding/
management of hypospadias. F1000Prime Rep. 2014;6:101.
5. Baskin LS, Ebbers MB. Hypospadias: anatomy, etiology, and
technique. J Pediatr Surg. 2006;41:463–472. A comprehensive
review of hypospadias, highlighting recent advancements in surgical
technique.
9. Duckett J, Snyder H. Meatal advancement and glanuloplasty
hypospadias repair after 1000 cases: avoidance of meatal stenosis
and regression. J Urol. 1992;147:665–669.
12. Snodgrass W, Koyle M, Manzoni G, et al. Tubularized incised plate
hypospadias repair: results of a multicenter experience. J Urol.
1996;156:839–841. Results of 148 patients undergoing TIP repair at six
centers are reported.
14. Bracka A. Hypospadias repair: the two stage alternative. Br J Urol.
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hypospadias repairs.
23. Rink RC, Cain MP. Urogenital mobilization for urogenital sinus
repair. BJU Int. 2008;102:1182–1197. This article provides an excellent
overview of the technical aspects of urogenital mobilization for
management of urogenital sinus.
27. Leclair MD, Gundeti M, Kiely EM, et al. The surgical outcome of
total urogenital mobilization for cloacal repair. J Urol. 2007;177:1492–
1495.
29. Palmer BW, Trojan B, Griffin K, et al. Total and partial urogenital
mobilization: focus on urinary continence. J Urol. 2012;187:1422–1426.
30. Creighton SM. Long-term outcomes of feminizing surgery: the
London experience. BJU Int. 2004;93:44–46.
41. Rajimwale A, Furness PD 3rd, Brant WO, et al. Vaginal construction
using sigmoid colon in children and young adults. Br J Urol Int.
2004;94:115–119. A large retrospective review of the surgeons’ experience
with sigmoid vaginoplasty, comparing pre- and postpubertal patient
outcomes.
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960.e1
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