Full text of DOI:10.1016/S0022-5347(05)67673-2

0022-5347/00/1635-1536/0
®
THE JOURNAL OF UROLOGY
Vol. 163, 1536–1539, May 2000
Copyright © 2000 by AMERICAN UROLOGICAL ASSOCIATION, INC.®
Printed in U.S.A.
Y-TO-I WRAP: USE OF THE DISTAL SPONGIOSUM FOR HYPOSPADIAS
REPAIR
ELIZABETH B. YERKES, MARK C. ADAMS, DAVID A. MILLER, JOHN C. POPE, IV,
RICHARD C. RINK AND JOHN W. BROCK, III
From the Vanderbilt Children’s Hospital, Vanderbilt University Medical Center, Nashville, Tennessee, and James Whitcomb Riley
Children’s Hospital, Indiana University Medical Center, Indianapolis, Indiana
ABSTRACT
Purpose: Rather than resecting the distal spongiosum lateral to the open urethra for hypos-
padias, we mobilized this tissue with the urethral plate away from the corpora cavernosa,
subsequently wrapping it around various types of urethroplasty to prevent fistula formation.
Materials and Methods: The distal spongiosum was preserved and used for coverage in 25
hypospadias repairs in 1 year. We initially applied it in this manner when the distal spongiosum
persisted as a pillar of healthy erectile tissue but later when the distal tissue appeared more
fibrous in nature. The wrap was used to cover various types of urethroplasty, including advance-
ment in 6 cases, tubularization in 10, flip-flap repair in 6 and an island onlay pedicle graft in 3.
Results: All patients have at least 1 year of followup. There has been no fistula formation or
residual chordee. In 1 patient minor meatal retraction did not require a secondary procedure.
Cosmetic results have been good.
Conclusions: A distal wrap of corpus spongiosum may be used to avoid fistula formation
without causing residual or recurrent curvature. It re-creates a nearly normal urethra in some
cases.
KEY WORDS: urethra, hypospadias, abnormalities
The current goals of hypospadias repair necessary for an The thin urethra is not deficient of spongiosum, but rather
excellent cosmetic and functional result include a straight this spongiosum erectile tissue is displaced laterally. In other
phallus, glanular meatus and good cosmetic skin coverage. cases the lateral spongiosum appears more fibrous. It is often
These various factors must be considered together through- more distinct proximally and fans out distally into or beneath
out repair, so that when the surgeon addresses a problem, the glans on each side. To correct chordee in the past this
such as chordee or the urethral defect, another part of recon- distal spongiosum was typically resected no matter what its
struction is not compromised. Several factors may contribute nature. We describe preservation of this tissue with mobili-
to chordee in patients with hypospadias. In mild curvature zation to cover various types of 1-stage urethroplasty for
the etiology may be a shortage of ventral penile skin or hypospadias repair. The spongiosum is initially in a Y con-
abnormal subcutaneous dartos tissue.1 Each problem is eas- figuration but as this lateral tissue is brought back together
ily identified and addressed after phallic degloving. Chordee over the urethra it appears as an I.
may also result from a short urethral plate, distal spongio-
sum tissue and corporeal disproportion.1
There is no question that there has been an evolution of
thought about the various contributions of these factors. Not
long ago a short urethral plate was believed to contribute to
chordee in many cases and, therefore, it was often divided.
With aggressive resection of distal spongiosum tissue and
mobilization of the urethral plate it has become clear that a
short urethral plate is often not the cause of curvature. Thus,
the urethral plate may be preserved and it is used in many
current repairs.2–4 Preservation has enabled the application
of flip-flap, incised plate and island onlay pedicle graft ure-
throplasty in many cases that were previously treated with
full tube pedicle grafts. In such a setting it is apparent in
many patients that the urethral plate may not be diseased,
although abnormal attachments from the urethral plate to
the underlying corpora may contribute to curvature. Curva-
ture secondary to corporeal disproportion generally requires
dorsal plication or ventral grafting for correction.
METHODS
The Y-to-I spongiosum wrap was used in 25 hypospadias
repairs in males 4 months to 23 years old. The technique was
applied in various forms of 1-stage urethroplasty, including
meatal advancement in 6 cases, tubularization of the ure-
thral plate with or without incision in 10, flip-flap repair in 6
and an onlay island pedicle graft in 3. Nine patients had
persistent penile curvature after degloving. In each case a
straight penis was achieved and documented by artifical
erection after preserving and mobilizing the urethral plate
and spongiosum. Two patients required a midline dorsal
plication suture for glanular tilt but none needed a dermal
graft.
In each case the distal spongiosum lateral to the urethral
plate was aggressively mobilized after the phallus was de-
gloved of skin and the remaining dartos tissue was resected
from the ventral corpora. We started dissection on the penile
shaft just lateral to the margin of the corpus spongiosum and
well proximal to the hypospadiac meatus (fig. 2). The spon-
giosum was easily dissected off of the underlying corpora
cavernosa lateral to medial. Mobilization was carried well
beneath the true urethral plate on either side but we did not
completely mobilize the midline spongiosum and urethral
plate from the corpora (fig. 2).
The distal corpus spongiosum on either side of the urethral
plate usually persists to some degree in patients with hypo-
spadias. In some cases it may be present as distinct pillars of
healthy erectile tissue. Such columns may even be apparent
through the penile skin before repair. This tissue is virtually
always associated with a thin distal native urethra (fig. 1).
Accepted for publication December 3, 1999.
1536

Y-TO-I WRAP FOR HYPOSPADIAS REPAIR
1537
FIG. 2. Spongiosum is mobilized with urethral plate. Dissection is
begun well proximal to meatus and spongiosum is incised trans-
FIG. 1. Thick pillars of spongiosum are nearly always lateral to
thin urethra, through which sound is passed. Spongiosum in forceps versely at end of urethral plate to avoid any longitudinal tension.
continues out next to urethral plate.
Mobilization is continued well behind urethral plate from either side
if not completely across corpora.
Recently we have completely elevated the urethral plate
and spongiosum without difficulty from the corpora across
the midline. Typically the spongiosum pillars spread beneath
the glans wings on each side. Care must be taken when
creating and mobilizing the glans wings to preserve the spon-
giosum distal with the urethral plate. Rather than a perpen-
dicular incision along the edges of the urethral plate within
the glans, which may remove the distal spongiosum with the
glans, we make an oblique incision at about 45 degrees,
which leaves healthy, thick glans wings yet intact spongio-
sum when done correctly. The proper plane is more easily
developed proximal to distal. It is initially defined on the
penile shaft, carried beneath the ventral coronal collar and
then from below into the glans. When established proximally,
the proper angle of dissection is generally obvious in this
manner, and leaves an adequate wrap and good glans wings
for closure. No glanular loss was noted in our cases.
FIG. 3. Lateral suture lines of flip-flap urethroplasty are com-
pletely covered with Y-to-I wrap. End appearance of neourethra is
virtually normal.
Failure to preserve the spongiosum wrap in continuity
distally leaves the urethra devoid of coverage at the level of
the coronal collar, where skin coverage may be more tenuous.
Spongiosum mobilization is continued distal to the end of the
urethral plate. In each case we incised the spongiosum trans-
versely at the end for complete spongiosum mobilization and
glans release (fig. 2). A tourniquet on the penis was not
needed when mobilizing the spongiosum. In fact, we occa-
sionally noted more bleeding when resecting healthy spon-
giosum tissue lateral to the urethral plate than when pre-
serving it. An artifical erection was then created in each
patient to ensure no residual curvature.
After completion of the urethroplasty the mobilized pillars
of distal spongiosum were wrapped to cover the neourethra
using fine absorbable suture. In most cases the spongiosum
was brought together in the midline. This maneuver is par-
ticularly effective for covering lateral urethroplasty suture
lines, as after a flip-flap repair (fig. 3). In these repairs the
was a pedicle flap of subcutaneous dartos tissue used over the
wrap of corpus spongiosum.
RESULTS
All 25 patients had at least 1 year of followup postopera-
tively (mean 28 months) and there was no fistula formation.
One boy had minor meatal retraction due to distal dehiscence
of the tubularized urethral plate. The meatus was only
slightly longer than normal and did not require surgical
revision. Cosmetic results were excellent and no residual or
recurrent chordee was noted.
DISCUSSION
In patients with hypospadias the open distal urethra and
urethra often appears normal after the spongiosum wrap. spongiosum may have abnormal attachments to the under-
Urethroplasty involving midline suture lines may be covered lying corpora that contribute to curvature. Historically the
by overlapping the spongiosum in a pants-over-vest fashion, urethral plate was often divided to straighten the phallus.
as in 6 of our patients. Also, 1 spongiosum flap may be Recent experience shows that the urethral plate is often
brought across the midline proximally and the other more adequate and may be preserved when adequately mobilized
distally as a modified Z-plasty. In most of our cases in this from the corpora. Likewise the distal spongiosum on either
series and in later cases the spongiosum wrap was closed side of the urethral plate was usually resected to correct
simply in the midline even for midline urethroplasty. Despite chordee. In its native position this tissue obviously may con-
concerns we have overlapped sutures with good results be- tribute to curvature due to its underlying attachments. How-
cause of the thick nature of the covering tissue. The thickness ever, like the urethral plate, this tissue may not inherently
of the spongiosum may even allow approximation in several be a problem. This richly vascularized tissue may be pre-
layers. We have carefully approximated the wrap to the back served if it is mobilized and placed back in the appropriate
of onlay flaps just proximal to the vascular pedicle, which position. We do not believe that such aggressive mobilization
covers the lateral suture lines of the urethroplasty well with- detracts from the vascularity and healing ability of the ure-
out compromising the blood supply. In none of our 25 cases thral plate. In fact, we think that it is much more supportive

1538
Y-TO-I WRAP FOR HYPOSPADIAS REPAIR
of the urethral plate to preserve this tissue than resect it. matic tissue handling, fine suture, meticulous performance of
One of the 2 maneuvers must generally be done when cur- urethroplasty with multilayer closure when possible, and
vature persists after phallic degloving.
interposition of subcutaneous and other tissue between the
In some patients the distal spongiosum may persist as urethroplasty and skin. Adherence to such principles is par-
healthy, well formed pillars of erectile tissue on each side of the ticularly critical at the proximal anastomosis and corona,
urethral plate. We initially recognized the potential of this where skin coverage may be more tenuous. The Y-to-I spon-
setting and began to preserve this tissue. Such columns are giosum wrap places erectile tissue back in its proper position
sometimes obvious even before phallic degloving and are virtu- and provides thick, healthy tissue for covering the urethro-
ally always present when there is an intact but thin urethra plasty and preventing fistula. Our small series does not de-
devoid of spongiosum in the midline. In other cases the distal finitively prove that the fistula rate is lower when spongio-
spongiosum may appear more fibrous in nature but it is on each sum is used in such a manner. Also, many urethroplasties
side of the urethral plate and often adequate for use.
were relatively minor or distal and, thus, they are associated
To preserve distal spongiosum for use in a Y-to-I wrap we with a low rate of fistula formation with or without this
aggressively mobilize the tissue with the urethral plate (fig. technique. It is our impression that with more experience,
4). Any abnormal attachment of erectile tissue to the under- particularly with more cases of proximal urethroplasty, pres-
lying corpora cavernosa must be released. Therefore, we start ervation and mobilization of spongiosum in this manner will
dissection on the spongiosum well proximal to the hypospa- decrease the chance of fistulization. We believe that it will do
diac meatus. The spongiosum is mobilized out to the end of so more effectively than dartos tissue because of the much
the urethral plate and incised transversely to prevent any thicker, vascular nature of erectile tissue.
longitudinal tension that may contribute to curvature. The
In our series it was not necessary to cover the spongiosum
spongiosum lateral to the urethral plate is completely mobi- wrap with a pedicle flap of dartos tissue or de-epithelialized
lized from the corpora with dissection carried well behind the skin, although such an added layer may easily be combined
urethral plate and more normal spongiosum or completely with this technique. We have subsequently done so on rare
across the midline. Typically there is a clear distinction when occasions. Park et al used a similar technique of urethral
this dissection reaches the true urethral plate because the advancement in patients with no penile chordee.5 When mo-
back side of the mobilized tissue is usually a different color. bilization is aggressive, we have noted that this technique is
Artifical erection should always be created to ensure ade- applicable in cases of curvature or severe urethral defects
quate mobilization and no persistent curvature.
and, therefore, for virtually any type of urethroplasty. When
We were careful not to carry dissection all the way to the the urethral plate is preserved, the adjacent spongiosum may
midline from each side of the urethral plate, particularly usually be preserved as well.
when we planned to incise the urethral plate longitudinally.
More recently, we have completely mobilized all of the spon-
CONCLUSIONS
giosum and urethral plate from the corpora to aid in chordee
Much like the urethral plate, the distal spongiosum in
correction. In many cases we proceeded with incised plate
most cases of hypospadias is not inherently diseased tissue
urethroplasty and a Y-to-I wrap despite complete mobiliza-
that causes chordee. Instead abnormal attachments of tissue
tion. In our most severe cases of hypospadias and chordee we
contribute to curvature. Thus, the distal spongiosum may be
still occasionally transect the urethral plate at its most distal
mobilized aggressively off of the underlying corpora caver-
end. We then place the previously elevated urethral plate
nosa in continuity with the urethral plate. It may then be
with spongiosum back on the underlying corpora after cor-
placed back into its normal anatomical position with a Y-to-I
recting curvature with or without a dermal graft. When doing
wrap and used to cover numerous types of urethroplasty. In
so, we take care not to advance the urethral plate too far and
that position it should inhibit fistula formation without caus-
re-create tethering. In some patients the mobilized urethra
ing residual curvature.
extends back out to the glans and in others it does not. In
either situation the spongiosum with the urethral plate has
REFERENCES
been thick enough in several cases to perform easily incised
1. Mouriquand, P. D., Persad, R. and Sharm, S.: Hypospadias re-
pair: current principles and procedures. Br J Urol, suppl., 76:
9, 1995
2. Elder, J. S., Duckett, J. W. and Snyder, H. M.: Onlay island flap
in the repair of mid and distal penile hypospadias without
chordee. J Urol, 138: 376, 1987
plate urethroplasty on the entire length of mobilized tissue
without any complication. This maneuver has resulted in a
much shorter remaining urethral defect.
In the evolution of hypospadias repair numerous elements
contribute to minimize fistula formation, including atrau-
3. Mollard, P., Mouriquand, P. D. and Felfela, T.: Application of the
onlay island flap urethroplasty to penile hypospadias with
severe chordee. Br J Urol, 68: 317, 1991
4. Baskin, L. S., Duckett, J. W., Ueoka, K. et al.: Changing concepts
of hypospadias curvature lead to more onlay island flap pro-
cedures. J Urol, 151: 191, 1994
5. Park, J. M., Faerber, G. J. and Bloom, D. A.: Long-term outcome
evaluation of patients undergoing the meatal advancement
and glanuloplasty procedure. J Urol, 153: 1655, 1995
EDITORIAL COMMENT
These authors detail a novel approach to neourethral reinforce-
ment. While certainly the spongiosum wrap would provide good
anatomical coverage as described, the opportunity to apply this tech-
nique would be rare in my experience. I concur with the authors that
the spongiosum pillars are frequently present in patients with a thin
or hypoplastic urethra. However, in the majority of patients I treat
who have distal hypospadias there is little if any usable spongiosum
tissue to incorporate into the repair.
The authors state that resection or mobilization of the spongiosum
pillars with urethral mobilization is necessary if curvature of the
phallus persists after penile degloving. While there is no argument
FIG. 4. If aggressively mobilized as shown, spongiosum may be
preserved with urethral plate and used to cover any urethroplasty.

Y-TO-I WRAP FOR HYPOSPADIAS REPAIR
1539
that this maneuver may improve chordee, one should not forget the to find or preserve adequate erectile tissue to wrap but in our
simpler and effective dorsal plication techniques for milder forms of experience this has been much more of the exception rather than the
persistent chordee. As it turned out, the authors still needed to resort rule. Surgeon perspective in looking for the tissue is important as
to dorsal plication in 2 cases of persistent glanular tilt.
one may not be able to find adequate spongiosum on distal repairs if
any tissue is resected lateral to the urethral plate or vertical inci-
sions are made next to the plate in the glans.
Another area of concern is why the authors would bother to perform
a spongiosum wrap for a meatal advancement procedure not requiring
tubularization of the urethra. This technique seems a bit over aggres-
sive surgically. They state that the spongiosum wrap is more effective
than the dartos tissue most commonly used today for covering the
neourethra because spongiosum tissue is thicker and more vascular. I
would direct the authors to examine more closely the outstanding
results in the literature achieved with a de-epithelialized subcutaneous
pedicle flap. My experience with the Belman flap1 in the last 10 years
has markedly decreased fistula formation to a rare event and has stood
the test of time. This thin but well vascularized pedicle stretches all the
way to the tip of the glans, giving complete neourethral coverage in
contrast to the spongiosum wrap. Hence, in these 25 cases further
experience is necessary to determine whether the spongiosum wrap
may successfully claim equality or even superiority to a time proved
coverage such as the Belman flap.
Zaontz suggests that dorsal plication of the corpora may be pref-
erable to mobilization or resection of spongiosum, and we disagree.
One might make an argument that the benefits of such plication may
be significant to preserve the urethral plate and avoid full tube
urethroplasty. We do not think that there is a significant benefit to
plication just to avoid any resection or mobilization of the sponge. It
is usually a simple matter to use 1 technique or the other, correct all
chordee and still preserve the urethral plate. Although we perform
some dorsal plications, the long-term reliability of newer and safer
plication techniques has not been established in boys going through
puberty. Therefore, we do not leave the spongiosum as is in boys with
curvature.
We also have used de-epithelialized subcutaneous pedicle flaps for
coverage of urethroplasty for years. We agree that for distal repairs
use of such coverage results in a low fistula rate. Like distal repairs,
this is also the case with the sponge wrap and would likely be true
with modern techniques if no coverage were used at all. With prox-
imal repairs when large areas must be covered, we have unfortu-
nately not found flaps of subcutaneous tissue to be universally ap-
plicable or effective. If one wants to compare the effectiveness of
tissue coverage, we expect any difference to be noted for proximal
and not distal repairs. The more experience that we have had with
this wrap, the more convinced we are that it provides effective
coverage of urethroplasty when preserved and mobilized appropri-
ately. We only suggest that readers try it and establish their own
Mark R. Zaontz
Department of Surgery
Cooper Hospital University Medical Center
Camden, New Jersey
1. Belman, A. B.: De-epithelialized skin flap coverage in hypospa-
dias repair. J Urol, 140: 1273, 1988
REPLY BY AUTHORS
We have now used this wrap of spongiosum for almost 150 hypo-
spadias repairs. During that time we have occasionally not been able bias about its application.