الفهرس 
EmbryologyOnly 14 pages are availabe for public view
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Abstract
SUMMARY
Hypospadias is an association of three anatomical
anomalies of the penis: an abnormal ventral opening of the
urethral meatus which can be located anywhere on the
ventral aspect of the penis, an abnormal ventral curvature
of the penis (chordee) and an abnormal distribution of the
foreskin around the glans with the ventrally deficient
hooded foreskin. The chordee is a common finding but not
a constant one.
Hypospadias appears at the crossroads of genetic and
environmental mechanisms. However the occurrence of
hypospadias remains unexplained in most cases. A
multifactorial explanation and the implication of unknown
genes or unidentified environmental factors remain
possible.
Hypospadias is the most common congenital anomaly of
the penis, affecting 0.4–8.2 of 1000 live male babies (10-
15% of which are proximal hypospadias.
Hypospadias is classified according to the meatal position,
as anterior or distal (glanular, coronal, subcoronal), middle
(midpenile), or posterior or proximal (posterior penile,
penoscrotal, scrotal, perineal). The level of division of the
corpus spongiosum may provide a more accurate mean of
classification.
The GMS hypospadias score is a standardized qualitative
method for scoring the severity of the hypospadias
complex.
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Karyotype, radiologic evaluation, laboratory investigations
and diagnostic surgical intervention help in diagnosis of
syndromic hypospadias when there are other nongenital
anomalies. It may also detect (DSD) especially when
proximal hypospadias is associated with cryptorchidism.
The most suitable age for operation of hypospadias is
between 6 and 18 months. The goals in management of
hypospadias repair are creating a straight penis, creating a
urethra of adequate length and uniform caliber,
reconstructing slit-like meatus at the tip of glans penis,
symmetry in appearance of glans and penile shaft and
projectile stream, these goals can be achieved by
orthoplasty, urethroplasty, meatoplasty, glanuloplasty,
scrotoplasty and skin covering.
Orthoplasty includes any procedure which aims to correct
the ventral curvature of the penis. Half of patients with
proximal hypospadias either had no ventral curvature after
the penis was degloved or had minor bending readily
correctable with single dorsal plication. The management
options of persistent severe curvature (greater than 30
degree) after degloving include multiple dorsal plications,
urethral plate division or urethral plate elevation. Ventral
penile lengthening procedure could be combined with these
procedures to correct residual severe curvature and to
prevent excessive penile shortening.
Urethroplasty means Reconstruction of neourethra. It can
be performed in a single stage or in a two-stage procedure.
After the penis has been straightened the decision of how to
reconstruct the neourethra strictly depends on whether the
urethral plate has been sectioned for straightening, and the
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characteristics of the plate. If the urethral plate has been
preserved, the 2 most popular alternatives for urethroplasty
are (TIP) and onlay preputial flap repair. If the urethral
plate has been transected, one-stage urethroplasty can be
accomplished by tubularized preputial flaps, Vertical
preputial island flap, the Koyanagi flap or the Lateral based
flap.
Several modifications were developed to improve the
results of Duckett tubularized preputial flaps such as the
two-layer closure of the neourethra, wrapping corpus
spongiosum tissue at the site of anastomosis, the use one
side of the island flap to recreate a urethral plate before
tubularization of preputial flap, re-fixation of dissected
urethral plate and dysplastic spongiosum to the corporal
body, fixation of the new urethra to the tunica albuginea at
the anastomosis line and additional fixation of the TPIF to
the midline of the corporal body and meatoplasty with Vincision
suture.
Several modifications were developed to improve the
results of OIF such as the double onlay preputial flap and
modified double face onlay island preputial skin flap with
augmented glanuloplasty.
Different types of modifications that make it possible to use
onlay flap after transection of the urethral plate include the
onlay-tube-onlay technique, the inlay-onlay flap,
lengthening the urethral plate with a double flap technique,
rebuilding the transected urethral plate using buccal
mucosal graft and inner preputial skin graft and onlay on
albuginea.
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Urethral plate elevation and urethral mobilization as a
technique for orthoplasty expands the spectrum of the TIP
application.
The high complication and reoperation rates after the
original Koyanagi’s operation were explained by the
inadequacy of blood supply to the neourethral flaps so
subsequent modifications of the Koyanagi repair aimed to
preserve a wide vascular pedicle for the distal skin flaps.
The lateral based flap enjoys double blood supply from
base of the meatus (as in the Mathieu flap) and from the
preputial vascular pedicle (as in Duckett island flap).
The lateral-based onlay flap technique is a reliable
technique for patients with proximal hypospadias in the
absence of a deep chordee. It has particular value in
patients with small or flat glans.
The staged technique is most frequently used for proximal
hypospadias with severe chordee (which require urethral
plate transection to achieve an adequate straightening), in
reoperative cases (where there is limited local skin and
blood supply is compromised) or in a few cases, injury to
the vascular pedicle of the preputial onlay or tube island
flap during harvest requires that the repair be staged.
‘Inverted U’ staged buccal mucosa graft (bracka) is a
modification was shown to avoid significant contracture of
the graft giving a more predictable size of the neourethra
for the second stage.
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Split dorsal dartos flap transposed ventrally as a bed for
preputial skin graft in primary staged hypospadias repair is
a modification offers some attractive advantages include
graft take is excellent, it provides the plentiful amount of
healthy and versatile dartos tissue so makes it easy to
performe a 4-layer urethroplasty (urethra, first dartos layer,
second dartos layer, skin closure) in the second stage and
unlike the original description by Bracka, there is no need
for degloving or extensive skin mobilization for harvesting
dartos fascia in the second stage.
An ideal follow-up will be at 1, 3, 6 months and then yearly
up to 2 years and long term follow-up at puberty and midteens
by which time genital maturity is at or near
completion and patient can express his social and sexual
problems following genital surgery. Assessment of
outcome includes: cosmetic appearance of the penis,
micturition, sexuality and psychosexual life and
complication.
Urethrocutaneous fistula is the most common complication
after hypospadias urethroplasty. However there are other
complications such as meatal stricture, urethral stricture,
balanitis xerotica obliterans, urethral diverticulum and
wound dehiscence.