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212 Hypospadias
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Figure 16.3 Causes of penile curvature associ-
ated with hypospadias.
from the abnormal meatus to the glans. Finally,
chordee may be due to an intrinsic exion deformity of the corpora cavernosa (Figure 16.3).
Correction of penile chordee should be addressed
in the following order:
1. Degloving the penis by fully mobilizing the
overlying skin. In most patients (80%), this
will correct the chordee.
2. Excision of the atretic and brous corpora
spongiosum proximally and distally to the
abnormal meatus.
3. Dissection of the urethral plate, which is
carefully elevated o the corpora cavernosa.
(Not all surgeons perform this step, opting
instead to go straight to a dorsal plication.)
In some patients ventral curvature of the penis
persists despite these steps, in which case it is necessary to plicate the dorsal aspect of the tunica
albuginea (Fig ure 16.4). Unfortunately, despite
dorsal plication there is a tendency for ventral
curvature to recur at puberty. If dorsal plication
is insucient to correct the degree of ventral curvature or where the surgeon’s preference dictates,
a more extensive corporal procedure (corporoplasty) may be indicated.
Urethroplasty
Reconstruction of the urethra can be performed
in a single stage or in a two-stage procedure.
Figure 16.4 Correction of intrinsic chordee by
plication on the dorsal aspect of the corpora,
following mobilization of the overlying neurovascular bundles.
Generally, a single-stage repair is appropriate
for distal, mid sha, and proximal hypospadias
without signicant chordee. A two-stage repair is
generally reserved for severe proximal or perineal
hypospadias with chordee and for “hypospadias
cripples.” Most surgeons now perform tubularization of the urethral plate as their preferred
one-stage method.
Tubularizing the urethral plate
(Figure 16.5)
e most widely used single-stage repair is a
Duplay-type tubularization incorporating a vertical incision in the urethral plate, as described
by Snodgrass. is allows the urethral plate to be
tubularized without tension. In addition, it has
been asserted that epithelialization of the urethral plate incision may contribute to the circumference of the neourethra.
In this procedure, the urethral plate is marked
and then deeply incised (Figu re 16.5a, b); its
width is then assessed. e urethral plate is
incised and then rolled into a tube (Figure 16.5d).
Some surgeons favor a modication in which a
free gra of preputial skin is inlaid into the incision in the urethral plate in the hope of reducing
the risk of contraction and stenosis of the neourethra (Figure 16.5b, c). If the urethral plate is
wide and suciently supple to be tubularized
Specic surgical principles / Urethroplasty 213
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Figure 16.5 (a) –(f) Key steps in tubularized incised plate (Snodgrass) repair (see text for
explanation).
over an 8 Fr catheter, it can be rolled into a tube
without the need for a urethral plate incision
(Duplay procedure) (Once the neourethra is
formed, a vascularized de-epithelialized pedicle
of tissue is placed over the anastomosis to reduce
stula formation (Figure 16.5d, e). e glanuloplasty is performed by reapproximating the glans
wings in two layers. e skin is then recongured, ensuring that there is adequate coverage on
the ventral surface so that penile chordee does
not recur (Fig ure 16. 5f). A dripping stent can be
le draining for 7 days. e authors have found
that a stent is rarely needed in children under 12
months of age.
Two-stage repair
(Figures 16.6 and 16.7)
e type of severe hypospadias for which a two
stage repair is most appropriate is illustrated in
Figu re 16.6.
e rst stage of the operation involves
correcting the chordee as described above
(Figu re16.7a, b) followed by preparing the glans
and harvesting the free ap (Figure 16.7c). Once
the chordee has been corrected, a midline ventral
incision is made from the most dorsal part of the
new meatus on the glans to the current meatus.
Glans wings are created so that the glans opens
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Figure 16.6 Severe proximal hypospadias –
unsuited to single-stage repair.
involves tubularization of the gra into the
neourethra (Figure 16.7f, g) and then placing a
second vascularized layer over the anastomosis (Figure 16.7h). Once this is completed the
glans is reconstructed and the penile skin closed
(Figu re 16.7i).
Other techniques which are still in current
usage are described below.
Urethral repositioning
e MAGPI procedure (Fig ure 16.8) is an acronym of “meatal advancement and glanuloplasty
incorporated”. It is only suitable for cases in
which the urethra is mobile – which can be conrmed if simple traction can move the meatus to
the tip of the glans. A vertical incision between
the tip of the glans and the meatus is created
(Figu re 16.8a, b) and then closed transversely,
thereby advancing the meatus. A circumferential
incision is made in the skin below the corona and
the meatus. e glanuloplasty is then performed
in two layers (Figure 16.8c, d), and nally the
penis is circumcised and the skin closed.
widely (“like a book”). e ideal material for the
ap should be easy to harvest, without leaving a
long-standing cosmetic defect. It should be supple
and non-hair bearing. e most commonly used
gra material is inner preputial skin. However,
postauricular Wolfe skin gras can also be used
for primary repair. Buccal mucosa and bladder
mucosa are less frequently used for standard twostage repairs but do have a role in “salvage” hypospadias repairs.
When the donor gra has been taken, the fat
and subepithelial tissue are removed to enhance
gra revascularization (Figure 16.7c). e gra
is then placed into the glans and tacked with
absorbable sutures; “windows” are made in the
gra to allow hematomas to escape and a few
midline quilting sutures are placed to anchor
the gra to on its base (Figure 16.7d, e). A rm
dressing is applied, with a catheter, which holds
the gra in place and minimizes hematoma formation. Aer 1 week the dressing and catheter
are removed. e second stage of the repair is
usually performed aer 6 months. is step
Pedicle aps
Two types of pedicle ap are commonly used,
the meatal-based ap and the preputial ap.
Both procedures utilize skin aps which remain
attached at some point to the urethral plate.
Meatal-based ap
(Mathieu procedure) (Figure 16.9)
e urethral plate is incised (Fig ure 16.9a) and
the glans aps developed. A vascularized ap of
proximal penile skin is created using the meatus
as the base (Fig ure 16.9b). e ap is then placed
on to the urethral plate and both lateral edges
are sutured to it. Adjacent subcutaneous tissue
is used to cover (“waterproof ”) the suture line
(Figu re 16.9c). Once the neourethra is created,
the glanuloplasty is performed (Figure 16.9d). As
a rule, the maximum length of this ap should be
no more than three times the width of the base
and in practice, this technique is unsuited for a
urethroplasty exceeding 1.5 cm.
Specic surgical principles / Urethroplasty 215
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Figure 16.7 (a)–(d) Key steps in the two-stage repair (see text for explanation).
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Figure 16.7 (Continued) (e)–(h) Key steps in the two-stage repair (see text for explanation).
Specic surgical principles / Common Variants of Hypospadias 217
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Figure 16.7 (Continued) (i) Key steps in the
two-stage repair (see text for explanation).
Preputial ap (onlay island ap
procedure) (Figure 16.10)
e urethral plate is incised vertically using two
parallel incisions. e penis is then degloved
back to its base using a circumferential subcoronal incision. e glans aps are then created
and the proximal thin urethra is cut back until
normal urethral tissue is found. A pedicle ap is
then created out of the inner prepuce, as shown
in Figure 16.10a. e preputial ap is brought
around the side of the penis to its ventral surface
and sutured to the urethral plate (Figu re 16.10b,
c). Once the neourethra has been created, the
subcutaneous pedicle is anchored to the tunica
albuginea lateral to the urethral anastomosis
(Figu re 16.10d). Occasionally, it is necessary to
divide the urethral plate in order to correct the
chordee. In these rare cases, the preputial ap can
be tubularized, thereby creating the neourethra
alone. e lateral glans wings are then approximated in two layers to recreate the glans, and the
skin is closed (Figure 16.10e).
e Koyanagi procedure and its variants are
alternative procedures for severe proximal hypospadias. It aims at using the urethral plate and the
neighboring strip of ventral tissues along with
the inner aspect of the preputial hood, which is
transferred ventrally with its pedicle. is large
and well-vascularized material is freed from the
ventral aspect of the corpus spongiosum down
to the base of the penis. is allows the penis to
straighten and to build an extended plate, which
is subsequently tubularized.
Covering the Penis
When the urethra has been reconstructed, it
is necessary to recreate the meatus, glans, and
occasionally the foreskin. Glanuloplasty is performed by bringing the two wings of the glans
around to cover the urethra; the glans is then
closed in two layers. e distal end of the neourethra is sutured to the new meatus, thereby
creating a slit-like opening. e residual inner
preputial skin adjacent to the coronal sulcus is
brought around the ventral side of the penis to
create a circumferential mucosal “cu ” or “collar” surrounding the glans. If parental preference is for preservation of the foreskin, a
prepucioplasty may also be performed to construct a foreskin. Skin coverage is provided by
moving the excess skin from the dorsal side to
the ventral side. ere are no signicant dierences in complication or revision rates when
comparing hypospadias repair with circumcision or prepucioplasty.
Common Variants of Hypospadias
Chordee without hypospadias
(Figure 16.11)
In most cases this is a misnomer since they do in
fact represent a form of hypospadias in which the
distal penile uret hra is imsy, despite the presence
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Figure 16.8 Urethral repositioning, key steps in the MAGPI repair (see text for explanation).
of a glanular meatus and circumferential prepuce.
It may be possible to achieve good correction by
degloving the sha and excising chordee tissue
while preserving an intact urethra. However, this
may not be possible if the urethra is imsy and
cannot be preserved intact. In such cases it is necessary to excise the abnormal urethral tissue back
to healthy spongiosum-supported urethra and
proceed to perform a urethroplasty as if it were
the corresponding degree of true hypospadias.
Megameatus intact prepuce
(Figure 16.12)
Because there is no external clue to the presence
of this variant it sometimes comes to light for
the rst time in a boy who is about to undergo
circumcision for cultural or medical reasons.
In this situation a planned cultural circumcision should be completed. If the circumcision
is being performed for medical reasons the
Specic surgical principles / Common Variants of Hypospadias 219
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Figure 16.9 Key steps in the perimeatal-based ap (Mathieu) repair (see text for explanation).
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Figure 16.10 Key steps in pedicle ap repair (see text for explanation).
surgeon should ideally explain the ndings to
the parents and seek their guidance before proceeding. If the parents opt for surgical correction of the glanular defect, referral to a specialist
is advisable.
“Salvage” or “redo” surgery oen calls for ingenuity and familiarity with a number of dierent
techniques. Where the neourethra is largely intact
and the surrounding skin is healthy, a procedure
using locally available skin may suce, but where
there is extensive scarring and, particularly in the
presence of residual chordee, it is usually preferable to abandon the unhealthy existing neourethra and perform a substitution procedure with
an onlay or tubularized free gra. Postauricular
skin is suitable, but buccal mucosa, harvested
from the lower lip (Figure 16.13) or cheek, is more
widely used for this purpose.
General surgical principles / Hormone Administration 221
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Figure 16.11 Chordee without hypospadias.
GENERAL SURGICAL
PRINCIPLES
Magnication
Most surgeons now use standard operating
loupes, which are easy to use and provide magnication in the range 2.5–4.5×.
Figure 16.13 Buccal mucosa graft – site on buc-
cal aspect of the lower lip marked out prior to
harvesting of the buccal skin graft for salvage
repair.
Hormone Administration
Anatomic factors such as glans width and development of the urethral plate have been shown
to correlate with surgical outcomes with a glans
width ≤14 mm being associated with an increased
risk of complications. Some surgeons administer
Figure 16.12 Megameatus intact prepuce variant (a) normal external appearances before the
prepuce is retracted, (b) glanular anomaly revealed by retraction of the prepuce, deep glans
groove with “sh mouth” megameatus.
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