- Email: [email protected]
Paraexstrophy Skin Flaps for the Primary Closure of Exstrophy in Boys: Outmoded or Updated?
Paraexstrophy Skin Flaps for the Primary Closure of Exstrophy in Boys: Outmoded or Updated? J. Todd Purves and John P. Gearhart* From the Jeffs Division of Pediatric Urology, Department of Urology, The Johns Hopkins University School of Medicine, Baltimore, Maryland
Purpose: We evaluated the current application of Duckett paraexstrophy skin flaps for bladder exstrophy reconstruction. Materials and Methods: We reviewed the records of cases of classic exstrophy treated at our institution between September 1993 and March 2007. A total of 21 patients were identified in whom modified Duckett paraexstrophy skin flaps were used in bladder closure at our institution. Another 12 patients were referred during the same time after closure with complications with flap use. Results: Of the 21 patients who underwent closure at our institution with our modified version of the Duckett flaps 1 (4%) had a complication, that is urethral stricture. This responded to internal urethrotomy and daily intermittent catheterization for 4 months, and the stricture stabilized. Four of the 12 referred patients responded to multiple urethral dilations, 3 underwent open repair with a buccal graft, 2 received a full-thickness skin graft and 3 underwent internal urethrotomy with daily intermittent catheterization for 4 months. Of our 21 patients with internal treatment 14 underwent bladder neck repair, 5 underwent epispadias repair and 2 were awaiting further reconstruction. Six of the 12 referred patients underwent bladder neck repair, 4 underwent epispadias repair and 2 were awaiting further reconstruction. Conclusions: By modifying our version of the Duckett paraexstrophy skin flaps we have lowered our complication rate significantly. While overall use of these flaps has continued to decrease, when they are required, these modifications help avoid complicating strictures and their sequelae in the bladder and upper urinary tract. Key Words: bladder, anomalies, exstrophy, surgical flaps, complications
major goal during primary exstrophy closure in the male patient is to adequately position the bladder and prostate sufficiently deep within the pelvis to configure a more normal anatomical position.1,2 However, in some boys the urethral plate is prohibitively short to accomplish this while leaving enough anterior urethra for subsequent penile reconstruction. Duckett overcame this difficulty by transecting the urethral plate distal to the verumontanum and then creating skin flaps from the shiny skin at the lower lateral margins of the exstrophic bladder.3 These paraexstrophy skin flaps were then rotated medial and used to bridge the gap between the transected edges of the urethra. The popularity of paraexstrophy skin flaps decreased after several investigators reported complications related to their use, most commonly strictures that required further interventions and untoward effects on bladder and renal function.4 – 6 Gearhart et al reported a complication rate of 40% in a series of 78 patients who underwent this technique.7 In the following editorial comment Duckett suggested that the source of obstructive complications may be that many surgeons anastomosed the skin flaps to the transected edge of the proximal urethral plate. He advocated that instead the flaps should extend to the bladder neck and along the lateral border of the prostatic urethra, thereby
A
Study received institutional review board approval. * Correspondence: Division of Pediatric Urology, The Johns Hopkins Hospital, 149 Marburg, 600 North Wolfe St., Baltimore, Maryland 21287 (telephone: 410-955-5358; e-mail: [email protected]).
0022-5347/08/1804-1675/0 THE JOURNAL OF UROLOGY® Copyright © 2008 by AMERICAN UROLOGICAL ASSOCIATION
effectively widening the strip of tissue before tubularization. When performing this modified Duckett paraexstrophy flap in 29 patients, he noted that stricture developed postoperatively in only 1 patient. We describe male patients who have since undergone exstrophy closure using the modified technique for paraexstrophy skin flaps, as proposed by Duckett.3
METHODS Between September 1993 and March 2007, 91 male patients underwent primary bladder exstrophy closure. Of those patients 21 required the creation of modified Duckett paraexstrophy skin flaps. With traction placed cephalad on the bladder and distal on the penis the paraexstrophy flaps are created from the shiny skin lateral to the inferior border of the bladder (fig. 1). The full-thickness flaps are mobilized and the urethra is divided with a V incision approximately 1 cm distal to the verumontanum (fig. 2). Division of the suspensory ligaments frees each corporeal body from the pubic bone (fig 3). The urogenital fibers are then transected (fig 4). The prostate is freed by carrying dissection cephalad and posterior to the prostate and inferior aspect of the bladder (fig 5). This allows placement of the vesicourethral unit deep in the pelvis. The paraexstrophy flaps are then brought medial to the midline and sutured to the lateral aspect of the prostatic urethra (fig. 6). According to the suggestion of Duckett the flaps are extended all the way to the bladder neck, which effectively
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Vol. 180, 1675-1679, October 2008 Printed in U.S.A. DOI:10.1016/j.juro.2008.03.088
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PARAEXSTROPHY SKIN FLAPS FOR PRIMARY EXSTROPHY CLOSURE
FIG. 1. With traction applied cephalad and caudal glabrous paraexstrophy skin at inferolateral borders of bladder template are outlined and incised.
FIG. 3. Corporeal bodies are freed from pubic bone by incising suspensory ligaments.
widens the proximal urethral plate.7 Note that the corpora cavernosa are not approximated at the midline since this will be performed at Cantwell-Ransley epispadias repair. The bladder and posterior urethra are then closed down to the level of the proximal penile shaft, resulting in proximal epispadias with a 12Fr opening and the expectation that the patient will be incontinent until further reconstruction
(fig. 7). Urethral stenting must be avoided to prevent trauma and edema, which can result in stricture formation. In year 1 following surgery renal and bladder ultrasound is done every 4 months and urine culture is obtained every 2 months. Following year 1 these tests are performed as needed. In addition to the 21 patients who underwent closure at our institution, another 12 were referred to us due to com-
FIG. 2. V incision is made transversely through urethral plate 1 cm distal to verumontanum. Full-thickness paraexstrophy skin flaps are mobilized.
FIG. 4. Complete and radical transection of urogenital fibers is critical step to allow placement of vesicourethral unit deep into pelvis.
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FIG. 5. Dissection is carried cephalad and medial behind prostate and lower aspect of bladder.
FIG. 7. Bladder and urethra are closed at midline down to proximal urethra, where aperture is calibrated to 12Fr.
plications associated with this type of flap. Data on all patients were extracted from the records in our institutionally approved exstrophy database.
had a complication, that is a 1 cm urethral stricture just distal to the prostatic urethra. This patient underwent internal urethrotomy by performing a single incision through the scar tissue at the 12 o’clock position. A Foley catheter was left in place for 2 weeks and daily intermittent catheterization was then performed for 4 months. This resulted in stricture resolution and no evidence of urinary obstruction when examined cystoscopically after 1 year. A total of 14 patients have undergone bladder neck repair, in 5 epispadias repair has been completed and the remaining 2 are awaiting further reconstruction. We have not noted any episodes of urinary tract infection or postoperative hydronephrosis. Four of the 12 patients referred for postoperative strictures had good results with multiple urethral dilations, 3 underwent open repair with a buccal graft, 2 underwent full-thickness skin grafting and 3 responded to internal urethrotomy with 4 months of daily intermittent catheterization. In 6 of these patients bladder neck repair has been completed, 4 have undergone epispadias repair and 2 are awaiting further reconstruction.
RESULTS Only 1 of the 21 patients (4%) who underwent closure at our institution with modified Duckett paraexstrophy skin flaps
DISCUSSION
FIG. 6. Paraexstrophy skin flaps are sewn to lateral aspect of prostatic urethra. They extend to inferior border of bladder to effectively widen plate used for tubularization.
In the 1993 study from our institution a 40% complication rate was noted in the entire population of 78 patients who underwent primary closure with the creation of paraexstrophy skin flaps.7 However, only 12 cases in this group were closed primarily at our institution and subsequently only 2 (17%) showed outlet obstruction. Since then, we have modified our technique to extend the flaps lateral to the prostatic urethra up the level of the bladder neck. The result was that our complication rate decreased to 1/21 patients (4%). The 1 child who experienced urethral stenosis responded well to conservative therapy with internal urethrotomy and 4 months of daily intermittent catheterization.
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Several groups have brought attention to the risks of paraexstrophy skin flaps and questioned their routine use. Borzi and Thomas found that the urethral reconstruction was compromised at the level of the paraexstrophy flaps, leading to the formation of strictures and fistulas.5 They also contended that penile length and continence were not enhanced by flaps and ideally the urethra should be left intact. We agree that penile length is not enhanced because the technique cannot compensate for the innately shorter penis in the patients with exstrophy. It is obviously impossible to compare penile length in patients who have and have not undergone a paraexstrophy skin flap procedure since the former group is selected for having a short urethral plate that may be at risk for penile shortening during closure. With regard to stricture and fistula formation we observed 1 case of the former and none of the latter. It is important to note that the skin flaps are created proximal to where the corporeal bodies meet and, therefore, they should not affect epispadias repair. In a population based study from Toronto Capolicchio et al found that urethral stenosis caused by paraexstrophy flaps worsened the continence rate in male patients.6 They suggested that gender inequality in overall continence rates with girls generally faring better than boys may be due to the greater number of bladder neck reconstructions performed in males, including the use of paraexstrophy skin flaps. In addition, they noted that groups at most exstrophy centers have abandoned the technique, which has partially resulted in the decrease in complications related to catheterizing a tortuous urethra. Even with current modifications paraexstrophy skin flaps carry an inherent risk of urethral stenosis and they probably do not confer significant benefit in most patients with exstrophy. Therefore, their routine use does not seem warranted at primary closure, as evidenced by the fact that it was only necessary in 21 of the 91 male patients (21%) with exstrophy closure. However, most exstrophy surgeons currently emphasize the positioning of the vesicourethral unit deep in the pelvis, which may be impossible in male patients with a particularly short urethral plate. Proper anatomical reconstruction in these patients would result in unacceptable shortening of the penis if the urethra were left intact. We believe that these patients benefit from urethral plate lengthening by transection and reconstruction with paraexstrophy skin flaps. In no cases have we used paraexstrophy skin flaps in females because the length of the urethral plate has not been found to limit the depth at which the bladder can be positioned. Obviously there are no concerns about shortening the external genitalia in girls, which is a main reason for using this technique in males. It should also be noted that our ability to use skin flaps is in part based on our choice of epispadias repair, specifically the modified Cantwell-Ransley technique. Surgeons who prefer complete penile disassembly repair should never use Duckett flaps since the distal and proximal blood supply would be compromised. CONCLUSIONS As illustrated in this article, modification of the Duckett paraexstrophy skin flap technique resulted in an improvement in complication rates by widening the prostatic ure-
thra. Due to the minority of patients with bladder exstrophy who would benefit from urethral transection this method should remain in the armamentarium of the exstrophy surgeon. ACKNOWLEDGMENTS Dedicated to Dr. John Warner Duckett, 1962 graduate of The Johns Hopkins University School of Medicine, role model, mentor and friend. REFERENCES 1.
Mathews R and Gearhart J: Modern staged reconstruction of bladder exstrophy—still the gold standard. Urology 2005; 65: 2. 2. Grady R and Mitchell M: Newborn exstrophy closure and epispadias repair. World J Urol 1998; 16: 200. 3. Duckett J: Use of paraexstrophy skin pedicle grafts for correction of exstrophy and epispadias repair. Birth Defects 1977; 13: 175. 4. Baker L, Jeffs R and Gearhart J: Urethral obstruction after primary exstrophy closure: what is the fate of the genitourinary tract? J Urol 1999; 161: 618. 5. Borzi P and Thomas D: Cantwell-Ransley epispadias repair in male epispadias and bladder exstrophy. J Urol 1994; 151: 457. 6. Capolicchio G, McLorie G, Farhart W, Merguerian P, Bagli D and Khoury A: A population based analysis of continence outcomes and bladder exstrophy. J Urol 2001; 165: 2418. 7. Gearhart J, Peppas D and Jeffs R: Complications of paraexstrophy skin flaps in the reconstruction of classical bladder exstrophy. J Urol 1993; 150: 627.
EDITORIAL COMMENT The use of paraexstrophy flaps has been abandoned by many surgeons because of concerns about postoperative urethral stricture or urethral devascularization in the setting of combined or complete exstrophy repair. These authors have taken advantage of their extensive experience with exstrophy to review the use of paraexstrophy flaps in the postmodification era. Considering the criticisms of the original technique, they subsequently modified it and have noted that paraexstrophy flaps can be safely used to reconstruct the urethra when applied judiciously. Longer term concerns surrounding the use of paraexstrophy flaps, including the potential of introducing hair bearing skin into the urinary tract, remain to be reported. A shortage of urethral tissue also often occurs with complete primary repair for exstrophy. In this situation I now favor a buccal graft to reconstruct the urethra since it is histologically similar to urethral epithelium. If regenerative medicine applications become more accessible, they will offer yet another and possibly a better solution to those that we currently have at hand. In the meantime the authors have reevaluated their post-modification results using paraexstrophy flaps. Richard Grady Division of Pediatric Urology University of Washington School of Medicine Children’s Hospital and Regional Medical Center Seattle, Washington
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DISCUSSION Dr. Michael Mitchell. I would like to comment about the Hopkins paper on the proximal repair using the Duckett urethral lengthening technique. I am not so sure we want to revisit this because in my limited experience with epispadias, although we call it the urethral plate, it is not a plate. It is the opened urethra and it has a corpus spongiosum posteriorly that comes down as a triangle of vascularized tissue, which is useful in reconstruction. It gets most of its blood supply from the bladder neck and proximal urethra, and not distally. That is what is unique about the exstrophy case and why we can take the penis totally apart. So if you want to lengthen, I do agree with the concept of needing to lengthen the urethra proximally. However, I think you can do that by just shaving out the tissue that has already transformed and its metaplastic tissue. It will not go back to a transitional epithelium. So you can just cut that tissue out and tubularize proximally for the primary closure. If the urethra is too short, just take the penis apart and bring it out proximally. Then at a later date you can do a distal urethroplasty, which we know how to do because it is just like a hypospadias repair. Dr. Todd Purves. That is a good point and obviously it would be good to point out that the use of paraexstrophy skin flaps when doing penile disassembly would be disastrous because you would not have the distal blood supply or the proximal supply. When using the modified Cantwell-Ransley technique we found that the distal blood supply has been absolutely sufficient. We have not seen any ischemic damage to the urethra or to the penis in any of our cases. Doctor Mitchell. You will not see ischemia of the penis because the blood supply for the penis comes from the central artery and dorsal complex. However, what you do see is ischemia of the urethra and that is why there is the potential for stricture. Doctor Purves. Correct, and we have not seen ischemic damage to the urethra when we have had to use these flaps, which I am not advocating should be used at all times. However, it is important for proper anatomic positioning of the vascular urethra unit and critical to avoid shortening an already short penis. In the infrequent circumstance when the modified Cantwell-Ransley procedure is used for epispadias repair these flaps can be part of the armamentarium.
Purpose: We evaluated the current application of Duckett paraexstrophy skin flaps for bladder exstrophy reconstruction. Materials and Methods: We reviewed the records of cases of classic exstrophy treated at our institution between September 1993 and March 2007. A total of 21 patients were identified in whom modified Duckett paraexstrophy skin flaps were used in bladder closure at our institution. Another 12 patients were referred during the same time after closure with complications with flap use. Results: Of the 21 patients who underwent closure at our institution with our modified version of the Duckett flaps 1 (4%) had a complication, that is urethral stricture. This responded to internal urethrotomy and daily intermittent catheterization for 4 months, and the stricture stabilized. Four of the 12 referred patients responded to multiple urethral dilations, 3 underwent open repair with a buccal graft, 2 received a full-thickness skin graft and 3 underwent internal urethrotomy with daily intermittent catheterization for 4 months. Of our 21 patients with internal treatment 14 underwent bladder neck repair, 5 underwent epispadias repair and 2 were awaiting further reconstruction. Six of the 12 referred patients underwent bladder neck repair, 4 underwent epispadias repair and 2 were awaiting further reconstruction. Conclusions: By modifying our version of the Duckett paraexstrophy skin flaps we have lowered our complication rate significantly. While overall use of these flaps has continued to decrease, when they are required, these modifications help avoid complicating strictures and their sequelae in the bladder and upper urinary tract. Key Words: bladder, anomalies, exstrophy, surgical flaps, complications
major goal during primary exstrophy closure in the male patient is to adequately position the bladder and prostate sufficiently deep within the pelvis to configure a more normal anatomical position.1,2 However, in some boys the urethral plate is prohibitively short to accomplish this while leaving enough anterior urethra for subsequent penile reconstruction. Duckett overcame this difficulty by transecting the urethral plate distal to the verumontanum and then creating skin flaps from the shiny skin at the lower lateral margins of the exstrophic bladder.3 These paraexstrophy skin flaps were then rotated medial and used to bridge the gap between the transected edges of the urethra. The popularity of paraexstrophy skin flaps decreased after several investigators reported complications related to their use, most commonly strictures that required further interventions and untoward effects on bladder and renal function.4 – 6 Gearhart et al reported a complication rate of 40% in a series of 78 patients who underwent this technique.7 In the following editorial comment Duckett suggested that the source of obstructive complications may be that many surgeons anastomosed the skin flaps to the transected edge of the proximal urethral plate. He advocated that instead the flaps should extend to the bladder neck and along the lateral border of the prostatic urethra, thereby
A
Study received institutional review board approval. * Correspondence: Division of Pediatric Urology, The Johns Hopkins Hospital, 149 Marburg, 600 North Wolfe St., Baltimore, Maryland 21287 (telephone: 410-955-5358; e-mail: [email protected]).
0022-5347/08/1804-1675/0 THE JOURNAL OF UROLOGY® Copyright © 2008 by AMERICAN UROLOGICAL ASSOCIATION
effectively widening the strip of tissue before tubularization. When performing this modified Duckett paraexstrophy flap in 29 patients, he noted that stricture developed postoperatively in only 1 patient. We describe male patients who have since undergone exstrophy closure using the modified technique for paraexstrophy skin flaps, as proposed by Duckett.3
METHODS Between September 1993 and March 2007, 91 male patients underwent primary bladder exstrophy closure. Of those patients 21 required the creation of modified Duckett paraexstrophy skin flaps. With traction placed cephalad on the bladder and distal on the penis the paraexstrophy flaps are created from the shiny skin lateral to the inferior border of the bladder (fig. 1). The full-thickness flaps are mobilized and the urethra is divided with a V incision approximately 1 cm distal to the verumontanum (fig. 2). Division of the suspensory ligaments frees each corporeal body from the pubic bone (fig 3). The urogenital fibers are then transected (fig 4). The prostate is freed by carrying dissection cephalad and posterior to the prostate and inferior aspect of the bladder (fig 5). This allows placement of the vesicourethral unit deep in the pelvis. The paraexstrophy flaps are then brought medial to the midline and sutured to the lateral aspect of the prostatic urethra (fig. 6). According to the suggestion of Duckett the flaps are extended all the way to the bladder neck, which effectively
1675
Vol. 180, 1675-1679, October 2008 Printed in U.S.A. DOI:10.1016/j.juro.2008.03.088
1676
PARAEXSTROPHY SKIN FLAPS FOR PRIMARY EXSTROPHY CLOSURE
FIG. 1. With traction applied cephalad and caudal glabrous paraexstrophy skin at inferolateral borders of bladder template are outlined and incised.
FIG. 3. Corporeal bodies are freed from pubic bone by incising suspensory ligaments.
widens the proximal urethral plate.7 Note that the corpora cavernosa are not approximated at the midline since this will be performed at Cantwell-Ransley epispadias repair. The bladder and posterior urethra are then closed down to the level of the proximal penile shaft, resulting in proximal epispadias with a 12Fr opening and the expectation that the patient will be incontinent until further reconstruction
(fig. 7). Urethral stenting must be avoided to prevent trauma and edema, which can result in stricture formation. In year 1 following surgery renal and bladder ultrasound is done every 4 months and urine culture is obtained every 2 months. Following year 1 these tests are performed as needed. In addition to the 21 patients who underwent closure at our institution, another 12 were referred to us due to com-
FIG. 2. V incision is made transversely through urethral plate 1 cm distal to verumontanum. Full-thickness paraexstrophy skin flaps are mobilized.
FIG. 4. Complete and radical transection of urogenital fibers is critical step to allow placement of vesicourethral unit deep into pelvis.
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FIG. 5. Dissection is carried cephalad and medial behind prostate and lower aspect of bladder.
FIG. 7. Bladder and urethra are closed at midline down to proximal urethra, where aperture is calibrated to 12Fr.
plications associated with this type of flap. Data on all patients were extracted from the records in our institutionally approved exstrophy database.
had a complication, that is a 1 cm urethral stricture just distal to the prostatic urethra. This patient underwent internal urethrotomy by performing a single incision through the scar tissue at the 12 o’clock position. A Foley catheter was left in place for 2 weeks and daily intermittent catheterization was then performed for 4 months. This resulted in stricture resolution and no evidence of urinary obstruction when examined cystoscopically after 1 year. A total of 14 patients have undergone bladder neck repair, in 5 epispadias repair has been completed and the remaining 2 are awaiting further reconstruction. We have not noted any episodes of urinary tract infection or postoperative hydronephrosis. Four of the 12 patients referred for postoperative strictures had good results with multiple urethral dilations, 3 underwent open repair with a buccal graft, 2 underwent full-thickness skin grafting and 3 responded to internal urethrotomy with 4 months of daily intermittent catheterization. In 6 of these patients bladder neck repair has been completed, 4 have undergone epispadias repair and 2 are awaiting further reconstruction.
RESULTS Only 1 of the 21 patients (4%) who underwent closure at our institution with modified Duckett paraexstrophy skin flaps
DISCUSSION
FIG. 6. Paraexstrophy skin flaps are sewn to lateral aspect of prostatic urethra. They extend to inferior border of bladder to effectively widen plate used for tubularization.
In the 1993 study from our institution a 40% complication rate was noted in the entire population of 78 patients who underwent primary closure with the creation of paraexstrophy skin flaps.7 However, only 12 cases in this group were closed primarily at our institution and subsequently only 2 (17%) showed outlet obstruction. Since then, we have modified our technique to extend the flaps lateral to the prostatic urethra up the level of the bladder neck. The result was that our complication rate decreased to 1/21 patients (4%). The 1 child who experienced urethral stenosis responded well to conservative therapy with internal urethrotomy and 4 months of daily intermittent catheterization.
1678
PARAEXSTROPHY SKIN FLAPS FOR PRIMARY EXSTROPHY CLOSURE
Several groups have brought attention to the risks of paraexstrophy skin flaps and questioned their routine use. Borzi and Thomas found that the urethral reconstruction was compromised at the level of the paraexstrophy flaps, leading to the formation of strictures and fistulas.5 They also contended that penile length and continence were not enhanced by flaps and ideally the urethra should be left intact. We agree that penile length is not enhanced because the technique cannot compensate for the innately shorter penis in the patients with exstrophy. It is obviously impossible to compare penile length in patients who have and have not undergone a paraexstrophy skin flap procedure since the former group is selected for having a short urethral plate that may be at risk for penile shortening during closure. With regard to stricture and fistula formation we observed 1 case of the former and none of the latter. It is important to note that the skin flaps are created proximal to where the corporeal bodies meet and, therefore, they should not affect epispadias repair. In a population based study from Toronto Capolicchio et al found that urethral stenosis caused by paraexstrophy flaps worsened the continence rate in male patients.6 They suggested that gender inequality in overall continence rates with girls generally faring better than boys may be due to the greater number of bladder neck reconstructions performed in males, including the use of paraexstrophy skin flaps. In addition, they noted that groups at most exstrophy centers have abandoned the technique, which has partially resulted in the decrease in complications related to catheterizing a tortuous urethra. Even with current modifications paraexstrophy skin flaps carry an inherent risk of urethral stenosis and they probably do not confer significant benefit in most patients with exstrophy. Therefore, their routine use does not seem warranted at primary closure, as evidenced by the fact that it was only necessary in 21 of the 91 male patients (21%) with exstrophy closure. However, most exstrophy surgeons currently emphasize the positioning of the vesicourethral unit deep in the pelvis, which may be impossible in male patients with a particularly short urethral plate. Proper anatomical reconstruction in these patients would result in unacceptable shortening of the penis if the urethra were left intact. We believe that these patients benefit from urethral plate lengthening by transection and reconstruction with paraexstrophy skin flaps. In no cases have we used paraexstrophy skin flaps in females because the length of the urethral plate has not been found to limit the depth at which the bladder can be positioned. Obviously there are no concerns about shortening the external genitalia in girls, which is a main reason for using this technique in males. It should also be noted that our ability to use skin flaps is in part based on our choice of epispadias repair, specifically the modified Cantwell-Ransley technique. Surgeons who prefer complete penile disassembly repair should never use Duckett flaps since the distal and proximal blood supply would be compromised. CONCLUSIONS As illustrated in this article, modification of the Duckett paraexstrophy skin flap technique resulted in an improvement in complication rates by widening the prostatic ure-
thra. Due to the minority of patients with bladder exstrophy who would benefit from urethral transection this method should remain in the armamentarium of the exstrophy surgeon. ACKNOWLEDGMENTS Dedicated to Dr. John Warner Duckett, 1962 graduate of The Johns Hopkins University School of Medicine, role model, mentor and friend. REFERENCES 1.
Mathews R and Gearhart J: Modern staged reconstruction of bladder exstrophy—still the gold standard. Urology 2005; 65: 2. 2. Grady R and Mitchell M: Newborn exstrophy closure and epispadias repair. World J Urol 1998; 16: 200. 3. Duckett J: Use of paraexstrophy skin pedicle grafts for correction of exstrophy and epispadias repair. Birth Defects 1977; 13: 175. 4. Baker L, Jeffs R and Gearhart J: Urethral obstruction after primary exstrophy closure: what is the fate of the genitourinary tract? J Urol 1999; 161: 618. 5. Borzi P and Thomas D: Cantwell-Ransley epispadias repair in male epispadias and bladder exstrophy. J Urol 1994; 151: 457. 6. Capolicchio G, McLorie G, Farhart W, Merguerian P, Bagli D and Khoury A: A population based analysis of continence outcomes and bladder exstrophy. J Urol 2001; 165: 2418. 7. Gearhart J, Peppas D and Jeffs R: Complications of paraexstrophy skin flaps in the reconstruction of classical bladder exstrophy. J Urol 1993; 150: 627.
EDITORIAL COMMENT The use of paraexstrophy flaps has been abandoned by many surgeons because of concerns about postoperative urethral stricture or urethral devascularization in the setting of combined or complete exstrophy repair. These authors have taken advantage of their extensive experience with exstrophy to review the use of paraexstrophy flaps in the postmodification era. Considering the criticisms of the original technique, they subsequently modified it and have noted that paraexstrophy flaps can be safely used to reconstruct the urethra when applied judiciously. Longer term concerns surrounding the use of paraexstrophy flaps, including the potential of introducing hair bearing skin into the urinary tract, remain to be reported. A shortage of urethral tissue also often occurs with complete primary repair for exstrophy. In this situation I now favor a buccal graft to reconstruct the urethra since it is histologically similar to urethral epithelium. If regenerative medicine applications become more accessible, they will offer yet another and possibly a better solution to those that we currently have at hand. In the meantime the authors have reevaluated their post-modification results using paraexstrophy flaps. Richard Grady Division of Pediatric Urology University of Washington School of Medicine Children’s Hospital and Regional Medical Center Seattle, Washington
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DISCUSSION Dr. Michael Mitchell. I would like to comment about the Hopkins paper on the proximal repair using the Duckett urethral lengthening technique. I am not so sure we want to revisit this because in my limited experience with epispadias, although we call it the urethral plate, it is not a plate. It is the opened urethra and it has a corpus spongiosum posteriorly that comes down as a triangle of vascularized tissue, which is useful in reconstruction. It gets most of its blood supply from the bladder neck and proximal urethra, and not distally. That is what is unique about the exstrophy case and why we can take the penis totally apart. So if you want to lengthen, I do agree with the concept of needing to lengthen the urethra proximally. However, I think you can do that by just shaving out the tissue that has already transformed and its metaplastic tissue. It will not go back to a transitional epithelium. So you can just cut that tissue out and tubularize proximally for the primary closure. If the urethra is too short, just take the penis apart and bring it out proximally. Then at a later date you can do a distal urethroplasty, which we know how to do because it is just like a hypospadias repair. Dr. Todd Purves. That is a good point and obviously it would be good to point out that the use of paraexstrophy skin flaps when doing penile disassembly would be disastrous because you would not have the distal blood supply or the proximal supply. When using the modified Cantwell-Ransley technique we found that the distal blood supply has been absolutely sufficient. We have not seen any ischemic damage to the urethra or to the penis in any of our cases. Doctor Mitchell. You will not see ischemia of the penis because the blood supply for the penis comes from the central artery and dorsal complex. However, what you do see is ischemia of the urethra and that is why there is the potential for stricture. Doctor Purves. Correct, and we have not seen ischemic damage to the urethra when we have had to use these flaps, which I am not advocating should be used at all times. However, it is important for proper anatomic positioning of the vascular urethra unit and critical to avoid shortening an already short penis. In the infrequent circumstance when the modified Cantwell-Ransley procedure is used for epispadias repair these flaps can be part of the armamentarium.