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PENILE DISASSEMBLY TECHNIQUE FOR EPISPADIAS REPAIR: VARIANTS OF TECHNIQUE
0022-5347/99/1623-1181/0
Vol. 162. 1181-1184. September 1999 Printed in U.S.A.
TflE JOlTR;\AL OF UROLOGY
Copyright 0 1999 by ANEKICAN UROLOGICAL ASSOCIATION, INC
PENILE DISASSEMBLY TECHNIQUE FOR EPISPADIAS REPAIR: VARIANTS OF TECHNIQUE SAVA V. PEROVIC, VOJKAN VUKADINOVIC, MIROSLAV LJ.DJORDJEVIC AND NENAD G. DJAKOVIC From the Department of Urology, University Children's Hospital, Belgrade, Yugoslavia
ABSTRACT
Purpose: We present 2 variants of the penile disassembly technique for epispadias repair that refine some details of the Mitchell technique. In some cases the urethral plate retracts and shortens, and there may be poor vascularization at the most distal portion. In addition, when the neurovascular bundles of the separated hemicorporeal glanular bodies are intact, i t is difficult to achieve excellent correction of dorsal chordee. Materials and Methods: Between 1995 and 1998 we performed the modified Mitchell technique in 11boys 2 to 14 years old using 1of 2 variants. For variant 1the hemiglans and urethral plate remain connected by a small tissue bridge to avoid shortening the urethral plate and ensure a better blood supply. For variant 2 each corporeal body is dissected from the glans cap and neurovascular bundle to achieve complete mobility. This procedure enables ideal mobility of the corporeal bodies as well as curvature repair. When corporeal rotation was unsuccessll, we corrected persistent dorsal chordee using the Ransley corporotomy with corporostomy in 2 patients and with dermal g r a f h g in 1. Results: Mean followup was 17 months (range 6 to 30). Dorsal curvature was corrected in all cases. Cosmetic appearance was good. Complications included meatal stenosis and urethral fistula in 1case each. Conclusions: Our variants of epispadias repair may be good alternatives to t h e Ransley and Mitchell complete penile disassembly techniques. KEY WORDS: penis, epispadias, abnormalities, urethra Epispadias repair remains a challenge. A great advance was achieved in the last decade by developing a radical approach. Ransley et a1 introduced a technique based on incomplete penile disassembly.' Mitchell and Bagli extended this technique into complete penile disassembly, which significantly changes the outcome of this procedure.2However, in some cases retraction and shortening of the urethral plate persist, and so it is difficult to bring the urethra to the top of the glans without tension. Also, the most distal portion of the urethral plate may be poorly vascularized. In addition, the intact neurovascular bundles of separated hemicorporeal glanular bodies make it difficult to achieve excellent correction of dorsal chordee. We present variants of the Mitchell technique to refine these details. MATERIALS A N D METHODS
From October 1995 to March 1998 we performed the modified Mitchell technique in 11 boys 2 to 14 years old, including 8 with epispadias and bladder exstrophy in whom exstrophy closure was performed previously and 3 with isolated epispadias. Two patients had undergone previously unsuccessful epispadias repair. In the modified technique the skin incision starts from the epispadiac meatus. The incision around the urethral plate is made more lateral, so that the urethral plate is wide enough to be tubularized later. Thus, injury to the neurovascular bundles close to the urethral plate is avoided. The incision continues to the border of the inner and outer layers of the prepuce. The inner preputial layer remains attached t o the glans to be subsequently used for reconstructing the subglanular portion of the penile skin, providing a better esthetic appearance of the penis. The urethral plate is separated from each corporeal body using the ventral and dorsal approach. The urethral plate
must be lifted with Bucks fascia to ensure the blood supply to the urethral plate and avoid injury to the spongiosal tissue. It is important to define the appropriate plane between the whole urethral plate with its blood supply and the corpora cavernosa with the hemiglans, which is best and most safely achieved by starting urethral plate dissection in the mid portion of the corpora cavernosa. The corporeal body is dissected proximal up to the attachments to the pubic bones. Further dissection is unnecessary and dangerous. There are 2 variants of distal dissection of the corpora cavernosa. For variant 1 the corpora cavernosa with the hemiglans and urethral plate remain connected by a small tissue bridge to avoid shortening the urethral plate and ensure a better blood supply. This technique does not affect the mobility or complete dorsal placement of the corporeal bodies. For variant 2 each corporeal body is dissected from the hemiglans with the neurovascular bundle and urethral plate, completely mobilizing the separated corpora cavernosa. This procedure is performed when excellent curvature repair may be achieved only after mobilization of the neurovascular bundles. For each variant it is essential to avoid injury to the neurovascular bundles, which run lateroventral into the hemiglans. Urethroplasty is performed by tubularizing the urethral plate. When the epispadiac urethral plate is short, it must be divided. Vascularized island preputial or penile skin flaps, or free grafts are interposed between the proximal and distal portions of the divided urethral plate. In some cases complete urethroplasty cannot be done in 1 stage. Therefore, it is advisable to create a hypospadiac meatus, which is repaired at stage 2. The corpora cavernosa are rotated and joined above the urethra. When corporeal rotation is unsuccessful, persistent dorsal chordee may be corrected by the Ransley corporotomy with corporostomy or dermal grafting. The ventralized urethra is fixed to the corpora cavernosa to prevent retraction. The
1181
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PENILE DISASSEMBLY TECHNIQUE FOR EPISPADWS REPAIR
FIG. 1. A, in variant 1corpora cavernosa with hemiglans and urethral plate remain connected by small tissue bridge to avoid shortening urethral plate and ensure better blood supply. This maneuver does not affect corporeal body mobility or complete dorsal placement. B , in variant 2 each corporeal body is dissected from hemiglans with neurovascular bundle and urethral plate to achieve complete mobility of separated corpora.
FIG. 2. A, when epispadiac urethral plate is short, it is divided in mid portion. B, vascularized island preputial skin flap is interposed between proximal and distal portions of divided urethral plate.
glanular portion of the neourethra is positioned at the ventral third of the glans to ensure an orthotopic meatus. Glanuloplasty usually involves reshaping the glans tissue to achieve a conical appearance. Reconstructing the penile skin is also difficult due to the common lack of available penile skin. The subglanular portion is reconstructed using the inner preputial layer and the penile shaft is usually covered with rotated pedicle skin flaps. This technique is performed during permanent erection induced by prostaglandin E 1. Permanent erection enables easier dissection of the penile entities and the precise correction of curvature by continuous evaluation before, during and after repair. The tips of the corpora cavernosa, which are incorporated into the glans cap, provide turgidity to the glans during erection. After dissecting the cavernous bodies from the glans cap, the cap becomes flaccid while the corpora remain erect (figs. 1 to 5).3 RESULTS
Mean followup was 27 months (range 6 months to 3 years). We performed variant 1 of the Mitchell technique in 8 pa-
tients and variant 2 in 3. Dorsal curvature was corrected in all cases without recurrence. There was no injury to the neurovascular bundles. Erection was preserved in all patients and evaluated by intracavernous injection of prostaglandin E l in each of the 2 corpora cavernosa. Cosmesis was satisfactory. Complications included meatal stenosis requiring corrective meatoplasty in 1case and penopubic fistula corrected surgically in 1. Patients with bladder exstrophy who were incontinent preoperatively remained incontinent after epispadias repair. However, the urinary stream, which was absent before surgery, appeared postoperatively due to outlet resistance. DISCUSSI 0N
Nearly a century ago Cantwell described the surgical repair of male epispadias.* Since then, our knowledge o f the anatomy of this anomaly as well as its surgical treatment has ev01ved.~The modifications of Ransley dramatically improved the results of epispadias repair by derotating the corpora cavernosa, securing with cavernocavernosostomy,
PENILE DISASSEMBLY TECHNIQUE FOR EPISPADIAS REPAIR
1183
FIG.3. A, corporeal bodies are completely separated from glans cap with urethra and neurovascular bundles. B , corporeal bodies are rejoined and dorsal chordee is repaired by rotating corpora cavernosa.
transferring the urethra ventrally and covering the dorsal aspect of the penis with a preputial flap.'z3 The penis dangles in the flaccid state and becomes straight in the erect state. The Mitchell technique extends the Cantwell-Ransley repair into a complete penile disassembly procedure that involves completely separating the urethral plate, and splitting the glans and corporeal bodies into separate halves with the blood supply on the 2 separated neurovascular bund l e ~ .The ~ , blood ~ supply to the urethral plate relies on the spongiosal tissue. Dorsal chordee is corrected using internal rotation of the 2 hemicorporeal glanular bodies, whereas the
FIG.4. Appearance at completion of surgery
neurovascular bundles mostly remain intact. Recently Grady and Mitchell reported a complete penile disassembly technique for epispadias repair simultaneously with exstrophy closure in newborns.' The completely free urethral plate enables movement of the bladder neck and urethra posteriorly in the pelvis in a more normal anatomical position. Movement of the bladder and urethra posteriorly in the pelvis as a unit optimizes the chance of early and consequently normal bladder development. Thus, urinary continence may be achieved. Reported results regarding urinary continence are encouraging and promising. The Cantwell-Ransley procedure is excellent for epispadias repair, especially compared to other standard methods. However, this technique has weaknesses. The most distal portion of the corpora cavernosa is not dissected and mobilized as well as the urethral plate. Thus, the glanular portion of the urethra is not covered with the corpora cavernosa, which may result in fistula formation at the subcoronal level. Limited mobility of the corpora cavernosa also prevents ideal urethral ventralization. A urethral plate that is not completely dissected represents a limiting factor in the successful use of this method for simultaneous exstrophy closure and epispadias repair in newborns. The Mitchell technique is the latest and in our opinion the best procedure for epispadias repair. However, some details of the technique have disadvantages in select cases. Retraction and shortening of the urethral plate are possible after complete penile disassembly. Therefore, it is difficult to bring the urethra up to the top of the glans without tension. In addition, the most distal portion of the urethral plate is poorly vascularized. The main blood supply to the urethral plate comes through the corpus spongiosum from proximally located arteries. The glans represents an extension of the corpus spongiosum and obtains the main blood supply from the neurovascular bundles. Thus, the glanular portion of the urethral plate is largely vascularized from the glans. The slight attachment of the urethral plate to the glans results in better vascularization of the most distal portion of the urethral plate. The suture line of the tubularized urethral plate lies dorsal at the glanular level and is completely covered with the joined tips of the corpora cavernosa, minimizing the risk of fistula formation. Dorsal chordee repair sometimes requires mobilizing the neurovascular bundles for ideal correction. That the neurovascular bundles remain intact and undisturbed is the great advantage of the Mitchell technique but it is no longer an advantage if the neurovascular bundles must be lifted from the corpora cavernosa to repair curvature. Lifting the neurovascular bundles is not necessary in newborns and infants, although it may be necessary in older children, especially adolescents. In some of our cases dorsal curvature was caused by fibrous chordee as well as by marked longitu-
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PENILE DISASSEMBLY TECHNIQUE FOR EPISPADIAS REPAIR
FIG. 5. A, marked dorsal curvature with corpora cavernosa free and erect, lying on anterior abdominal wall. B , curvature is repaired by incisional grafting technique. Erection shows completely straightened corpora cavernosa.
CONCLUSIONS
dinal prominence of the thickened duplicated tunica albuginea. Corporotomies with grafting were necessary to repair these cases without penile shortening. This correction may only be performed in completely free cavernous bodies. There is a risk of damage to the neurovascular bundles during lifting. However, the Cantwell-Ransley technique, which includes dissection of the neurovascular bundles, has proved successful with time. This risk inspired us to introduce 2 variants of the Mitchell technique. In variant 1 the hemiglans and urethral plate are connected by a small tissue bridge to avoid shortening the urethral plate and ensure a better blood supply. This maneuver does not affect mobility of the tips of the corporeal bodies or their complete dorsal placement. In variant 2 each corporeal body is dissected from the glans cap and neurovascular bundle to achieve complete mobility. Our penile disassembly technique enables preservation of the blood supply to the most distal portion of the urethral plate as well as great mobility and an excellent approach to repairing the completely free corpora cavernosa. Our variants of the Mitchell technique have some disadvantages. They cannot be used in newborns, especially for simultaneous exstrophy closure and epispadias repair. These variants are also not recommended for inexperienced surgeons who are unfamiliar with dissecting the penis. Overall this is not a routine procedure.
The Mitchell technique is a great advance in the evolution of epispadias repair. Our variants of this procedure may be good alternatives only in select cases and in the hands of experienced surgeons who are highly familiar with dissecting the penis. More patients and long-term followup are needed t o confirm how our variants of the Mitchell technique fit in the surgical armamentarium of epispadias repair. REFERENCES
1. Ransley, P. G., Duffy, P. G. and Wollin, M.: Bladder exstrophy closure and epispadias repair. In: Rob and Smith's Operative Surgery. Paediatric Surgery, 4th ed. Edited by L. Spitz and H. H. Nixon. Boston: Buttenvorths, pp. 620-622, 1988. 2. Mitchell, M. E. and Bagli, D. J.: Complete penile disassembly for epispadias repair: Mitchell technique. J. Urol., 155 300, 1996. 3. Perovic, S., Djordjevic, M. and Djakovic, N.: Natural erection induced by prostaglandin-El in the diagnosis and treatment of congenital penile anomalies. Brit. J. Urol., 7 9 43, 1997. 4. Cantwell, F. V.: Operative treatment of epispadias by transplantation of the urethra. Ann. Surg., 2 2 689, 1895. 5. Gearhart, J. P.: Editorial: evolution of epispadias repairtiming, techniques and results. J. Urol., 160 177, 1998. 6. Mollard, P., Basset, T. and Mure, P. Y.: Male epispadias: experience with 45 cases. J. Urol., 160 55, 1998. 7. Zaontz, M. R., Steckler, R. E., Dairiki Shortliffe, L. M., Kogan, B. A. and Tekgul, S.: Multicenter experience with the Mitchell technique for epispadias repair. J. Urol., 160 172, 1998. 8. Grady, R. W. and Mitchell, M. E.: Newborn exstrophy and epispadias repair. World J. Urol., 1 6 200, 1998.
DISCUSSION
Dr. Howard M. Snyder. I am impressed with the experience with the Mitchell dissection. If you start dissection in the mid shaft, the dissection plane is established. By doing that you may preseme the full length of the urethral plate. That combined with increased exposure proximally by taking the corporeal bodies completely apart gives much better exposure. Dr. Sava V.Perovic. My preference in this type of surgery is to find the correct plane, which you may fmd if you approach the mid part of the corpora cavernosa first ventrally and then dorsally, and then go farther proximal and strictly distal to the glans to avoid injury.In this disassembly technique you must be familiar with dissection. I think that there are good conditions of epispadias anatomically for dissecting the penis without a problem. Dr. Michael E. Mitchell. I agree that the initial approach is on the underside of the penis in the mid urethra, where the corpora start to separate. Remember that this is a triangle of tissue. Just follow the corpora around and then go dorsal. Start in the mid portion of the plate on the lateral aspects and follow the tunica albuginea around. Sooner or later you come together.
Vol. 162. 1181-1184. September 1999 Printed in U.S.A.
TflE JOlTR;\AL OF UROLOGY
Copyright 0 1999 by ANEKICAN UROLOGICAL ASSOCIATION, INC
PENILE DISASSEMBLY TECHNIQUE FOR EPISPADIAS REPAIR: VARIANTS OF TECHNIQUE SAVA V. PEROVIC, VOJKAN VUKADINOVIC, MIROSLAV LJ.DJORDJEVIC AND NENAD G. DJAKOVIC From the Department of Urology, University Children's Hospital, Belgrade, Yugoslavia
ABSTRACT
Purpose: We present 2 variants of the penile disassembly technique for epispadias repair that refine some details of the Mitchell technique. In some cases the urethral plate retracts and shortens, and there may be poor vascularization at the most distal portion. In addition, when the neurovascular bundles of the separated hemicorporeal glanular bodies are intact, i t is difficult to achieve excellent correction of dorsal chordee. Materials and Methods: Between 1995 and 1998 we performed the modified Mitchell technique in 11boys 2 to 14 years old using 1of 2 variants. For variant 1the hemiglans and urethral plate remain connected by a small tissue bridge to avoid shortening the urethral plate and ensure a better blood supply. For variant 2 each corporeal body is dissected from the glans cap and neurovascular bundle to achieve complete mobility. This procedure enables ideal mobility of the corporeal bodies as well as curvature repair. When corporeal rotation was unsuccessll, we corrected persistent dorsal chordee using the Ransley corporotomy with corporostomy in 2 patients and with dermal g r a f h g in 1. Results: Mean followup was 17 months (range 6 to 30). Dorsal curvature was corrected in all cases. Cosmetic appearance was good. Complications included meatal stenosis and urethral fistula in 1case each. Conclusions: Our variants of epispadias repair may be good alternatives to t h e Ransley and Mitchell complete penile disassembly techniques. KEY WORDS: penis, epispadias, abnormalities, urethra Epispadias repair remains a challenge. A great advance was achieved in the last decade by developing a radical approach. Ransley et a1 introduced a technique based on incomplete penile disassembly.' Mitchell and Bagli extended this technique into complete penile disassembly, which significantly changes the outcome of this procedure.2However, in some cases retraction and shortening of the urethral plate persist, and so it is difficult to bring the urethra to the top of the glans without tension. Also, the most distal portion of the urethral plate may be poorly vascularized. In addition, the intact neurovascular bundles of separated hemicorporeal glanular bodies make it difficult to achieve excellent correction of dorsal chordee. We present variants of the Mitchell technique to refine these details. MATERIALS A N D METHODS
From October 1995 to March 1998 we performed the modified Mitchell technique in 11 boys 2 to 14 years old, including 8 with epispadias and bladder exstrophy in whom exstrophy closure was performed previously and 3 with isolated epispadias. Two patients had undergone previously unsuccessful epispadias repair. In the modified technique the skin incision starts from the epispadiac meatus. The incision around the urethral plate is made more lateral, so that the urethral plate is wide enough to be tubularized later. Thus, injury to the neurovascular bundles close to the urethral plate is avoided. The incision continues to the border of the inner and outer layers of the prepuce. The inner preputial layer remains attached t o the glans to be subsequently used for reconstructing the subglanular portion of the penile skin, providing a better esthetic appearance of the penis. The urethral plate is separated from each corporeal body using the ventral and dorsal approach. The urethral plate
must be lifted with Bucks fascia to ensure the blood supply to the urethral plate and avoid injury to the spongiosal tissue. It is important to define the appropriate plane between the whole urethral plate with its blood supply and the corpora cavernosa with the hemiglans, which is best and most safely achieved by starting urethral plate dissection in the mid portion of the corpora cavernosa. The corporeal body is dissected proximal up to the attachments to the pubic bones. Further dissection is unnecessary and dangerous. There are 2 variants of distal dissection of the corpora cavernosa. For variant 1 the corpora cavernosa with the hemiglans and urethral plate remain connected by a small tissue bridge to avoid shortening the urethral plate and ensure a better blood supply. This technique does not affect the mobility or complete dorsal placement of the corporeal bodies. For variant 2 each corporeal body is dissected from the hemiglans with the neurovascular bundle and urethral plate, completely mobilizing the separated corpora cavernosa. This procedure is performed when excellent curvature repair may be achieved only after mobilization of the neurovascular bundles. For each variant it is essential to avoid injury to the neurovascular bundles, which run lateroventral into the hemiglans. Urethroplasty is performed by tubularizing the urethral plate. When the epispadiac urethral plate is short, it must be divided. Vascularized island preputial or penile skin flaps, or free grafts are interposed between the proximal and distal portions of the divided urethral plate. In some cases complete urethroplasty cannot be done in 1 stage. Therefore, it is advisable to create a hypospadiac meatus, which is repaired at stage 2. The corpora cavernosa are rotated and joined above the urethra. When corporeal rotation is unsuccessful, persistent dorsal chordee may be corrected by the Ransley corporotomy with corporostomy or dermal grafting. The ventralized urethra is fixed to the corpora cavernosa to prevent retraction. The
1181
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PENILE DISASSEMBLY TECHNIQUE FOR EPISPADWS REPAIR
FIG. 1. A, in variant 1corpora cavernosa with hemiglans and urethral plate remain connected by small tissue bridge to avoid shortening urethral plate and ensure better blood supply. This maneuver does not affect corporeal body mobility or complete dorsal placement. B , in variant 2 each corporeal body is dissected from hemiglans with neurovascular bundle and urethral plate to achieve complete mobility of separated corpora.
FIG. 2. A, when epispadiac urethral plate is short, it is divided in mid portion. B, vascularized island preputial skin flap is interposed between proximal and distal portions of divided urethral plate.
glanular portion of the neourethra is positioned at the ventral third of the glans to ensure an orthotopic meatus. Glanuloplasty usually involves reshaping the glans tissue to achieve a conical appearance. Reconstructing the penile skin is also difficult due to the common lack of available penile skin. The subglanular portion is reconstructed using the inner preputial layer and the penile shaft is usually covered with rotated pedicle skin flaps. This technique is performed during permanent erection induced by prostaglandin E 1. Permanent erection enables easier dissection of the penile entities and the precise correction of curvature by continuous evaluation before, during and after repair. The tips of the corpora cavernosa, which are incorporated into the glans cap, provide turgidity to the glans during erection. After dissecting the cavernous bodies from the glans cap, the cap becomes flaccid while the corpora remain erect (figs. 1 to 5).3 RESULTS
Mean followup was 27 months (range 6 months to 3 years). We performed variant 1 of the Mitchell technique in 8 pa-
tients and variant 2 in 3. Dorsal curvature was corrected in all cases without recurrence. There was no injury to the neurovascular bundles. Erection was preserved in all patients and evaluated by intracavernous injection of prostaglandin E l in each of the 2 corpora cavernosa. Cosmesis was satisfactory. Complications included meatal stenosis requiring corrective meatoplasty in 1case and penopubic fistula corrected surgically in 1. Patients with bladder exstrophy who were incontinent preoperatively remained incontinent after epispadias repair. However, the urinary stream, which was absent before surgery, appeared postoperatively due to outlet resistance. DISCUSSI 0N
Nearly a century ago Cantwell described the surgical repair of male epispadias.* Since then, our knowledge o f the anatomy of this anomaly as well as its surgical treatment has ev01ved.~The modifications of Ransley dramatically improved the results of epispadias repair by derotating the corpora cavernosa, securing with cavernocavernosostomy,
PENILE DISASSEMBLY TECHNIQUE FOR EPISPADIAS REPAIR
1183
FIG.3. A, corporeal bodies are completely separated from glans cap with urethra and neurovascular bundles. B , corporeal bodies are rejoined and dorsal chordee is repaired by rotating corpora cavernosa.
transferring the urethra ventrally and covering the dorsal aspect of the penis with a preputial flap.'z3 The penis dangles in the flaccid state and becomes straight in the erect state. The Mitchell technique extends the Cantwell-Ransley repair into a complete penile disassembly procedure that involves completely separating the urethral plate, and splitting the glans and corporeal bodies into separate halves with the blood supply on the 2 separated neurovascular bund l e ~ .The ~ , blood ~ supply to the urethral plate relies on the spongiosal tissue. Dorsal chordee is corrected using internal rotation of the 2 hemicorporeal glanular bodies, whereas the
FIG.4. Appearance at completion of surgery
neurovascular bundles mostly remain intact. Recently Grady and Mitchell reported a complete penile disassembly technique for epispadias repair simultaneously with exstrophy closure in newborns.' The completely free urethral plate enables movement of the bladder neck and urethra posteriorly in the pelvis in a more normal anatomical position. Movement of the bladder and urethra posteriorly in the pelvis as a unit optimizes the chance of early and consequently normal bladder development. Thus, urinary continence may be achieved. Reported results regarding urinary continence are encouraging and promising. The Cantwell-Ransley procedure is excellent for epispadias repair, especially compared to other standard methods. However, this technique has weaknesses. The most distal portion of the corpora cavernosa is not dissected and mobilized as well as the urethral plate. Thus, the glanular portion of the urethra is not covered with the corpora cavernosa, which may result in fistula formation at the subcoronal level. Limited mobility of the corpora cavernosa also prevents ideal urethral ventralization. A urethral plate that is not completely dissected represents a limiting factor in the successful use of this method for simultaneous exstrophy closure and epispadias repair in newborns. The Mitchell technique is the latest and in our opinion the best procedure for epispadias repair. However, some details of the technique have disadvantages in select cases. Retraction and shortening of the urethral plate are possible after complete penile disassembly. Therefore, it is difficult to bring the urethra up to the top of the glans without tension. In addition, the most distal portion of the urethral plate is poorly vascularized. The main blood supply to the urethral plate comes through the corpus spongiosum from proximally located arteries. The glans represents an extension of the corpus spongiosum and obtains the main blood supply from the neurovascular bundles. Thus, the glanular portion of the urethral plate is largely vascularized from the glans. The slight attachment of the urethral plate to the glans results in better vascularization of the most distal portion of the urethral plate. The suture line of the tubularized urethral plate lies dorsal at the glanular level and is completely covered with the joined tips of the corpora cavernosa, minimizing the risk of fistula formation. Dorsal chordee repair sometimes requires mobilizing the neurovascular bundles for ideal correction. That the neurovascular bundles remain intact and undisturbed is the great advantage of the Mitchell technique but it is no longer an advantage if the neurovascular bundles must be lifted from the corpora cavernosa to repair curvature. Lifting the neurovascular bundles is not necessary in newborns and infants, although it may be necessary in older children, especially adolescents. In some of our cases dorsal curvature was caused by fibrous chordee as well as by marked longitu-
1184
PENILE DISASSEMBLY TECHNIQUE FOR EPISPADIAS REPAIR
FIG. 5. A, marked dorsal curvature with corpora cavernosa free and erect, lying on anterior abdominal wall. B , curvature is repaired by incisional grafting technique. Erection shows completely straightened corpora cavernosa.
CONCLUSIONS
dinal prominence of the thickened duplicated tunica albuginea. Corporotomies with grafting were necessary to repair these cases without penile shortening. This correction may only be performed in completely free cavernous bodies. There is a risk of damage to the neurovascular bundles during lifting. However, the Cantwell-Ransley technique, which includes dissection of the neurovascular bundles, has proved successful with time. This risk inspired us to introduce 2 variants of the Mitchell technique. In variant 1 the hemiglans and urethral plate are connected by a small tissue bridge to avoid shortening the urethral plate and ensure a better blood supply. This maneuver does not affect mobility of the tips of the corporeal bodies or their complete dorsal placement. In variant 2 each corporeal body is dissected from the glans cap and neurovascular bundle to achieve complete mobility. Our penile disassembly technique enables preservation of the blood supply to the most distal portion of the urethral plate as well as great mobility and an excellent approach to repairing the completely free corpora cavernosa. Our variants of the Mitchell technique have some disadvantages. They cannot be used in newborns, especially for simultaneous exstrophy closure and epispadias repair. These variants are also not recommended for inexperienced surgeons who are unfamiliar with dissecting the penis. Overall this is not a routine procedure.
The Mitchell technique is a great advance in the evolution of epispadias repair. Our variants of this procedure may be good alternatives only in select cases and in the hands of experienced surgeons who are highly familiar with dissecting the penis. More patients and long-term followup are needed t o confirm how our variants of the Mitchell technique fit in the surgical armamentarium of epispadias repair. REFERENCES
1. Ransley, P. G., Duffy, P. G. and Wollin, M.: Bladder exstrophy closure and epispadias repair. In: Rob and Smith's Operative Surgery. Paediatric Surgery, 4th ed. Edited by L. Spitz and H. H. Nixon. Boston: Buttenvorths, pp. 620-622, 1988. 2. Mitchell, M. E. and Bagli, D. J.: Complete penile disassembly for epispadias repair: Mitchell technique. J. Urol., 155 300, 1996. 3. Perovic, S., Djordjevic, M. and Djakovic, N.: Natural erection induced by prostaglandin-El in the diagnosis and treatment of congenital penile anomalies. Brit. J. Urol., 7 9 43, 1997. 4. Cantwell, F. V.: Operative treatment of epispadias by transplantation of the urethra. Ann. Surg., 2 2 689, 1895. 5. Gearhart, J. P.: Editorial: evolution of epispadias repairtiming, techniques and results. J. Urol., 160 177, 1998. 6. Mollard, P., Basset, T. and Mure, P. Y.: Male epispadias: experience with 45 cases. J. Urol., 160 55, 1998. 7. Zaontz, M. R., Steckler, R. E., Dairiki Shortliffe, L. M., Kogan, B. A. and Tekgul, S.: Multicenter experience with the Mitchell technique for epispadias repair. J. Urol., 160 172, 1998. 8. Grady, R. W. and Mitchell, M. E.: Newborn exstrophy and epispadias repair. World J. Urol., 1 6 200, 1998.
DISCUSSION
Dr. Howard M. Snyder. I am impressed with the experience with the Mitchell dissection. If you start dissection in the mid shaft, the dissection plane is established. By doing that you may preseme the full length of the urethral plate. That combined with increased exposure proximally by taking the corporeal bodies completely apart gives much better exposure. Dr. Sava V.Perovic. My preference in this type of surgery is to find the correct plane, which you may fmd if you approach the mid part of the corpora cavernosa first ventrally and then dorsally, and then go farther proximal and strictly distal to the glans to avoid injury.In this disassembly technique you must be familiar with dissection. I think that there are good conditions of epispadias anatomically for dissecting the penis without a problem. Dr. Michael E. Mitchell. I agree that the initial approach is on the underside of the penis in the mid urethra, where the corpora start to separate. Remember that this is a triangle of tissue. Just follow the corpora around and then go dorsal. Start in the mid portion of the plate on the lateral aspects and follow the tunica albuginea around. Sooner or later you come together.