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Iatrogenic prostatic urethral strictures: classification and endoscopic treatment
ADULT UROLOGY
IATROGENIC PROSTATIC URETHRAL STRICTURES: CLASSIFICATION AND ENDOSCOPIC TREATMENT VITO PANSADORO
AND
PAOLO EMILIOZZI
ABSTRACT Objectives. The treatment of posterior urethral strictures is a controversial subject. For proper treatment, it is important to differentiate between iatrogenic prostatic urethral strictures and post-traumatic membranous urethral strictures. Methods. Iatrogenic strictures of the prostatic urethra have been classified according to location and etiology into three categories: type I, located exclusively at the bladder neck; type II, located in the midportion of the prostatic fossa; and type III, when the whole prostatic fossa is replaced by stricture. From 1970 to 1996, 163 patients with postoperative strictures of the prostatic urethra were treated endoscopically. Results. The results obtained in 122 patients are reported; 41 patients are not evaluable. The median follow-up was 63 months (range 12 to 239). Seven patients required a second endoscopic procedure to attain cure. Good results were achieved in 54 (91%) of 59 patients with type I strictures, in 45 (98%) of 46 patients with type II strictures, and in 13 (76%) of 17 patients with type III strictures. The overall success rate was 92% (112 of 122). Complications occurred in 21 patients (17%), including postoperative urinary tract infection (11%), incontinence (4%), stress incontinence (1%), and severe bleeding (1%). Conclusions. Postoperative strictures of the prostatic urethra must be recognized and can be easily treated with endoscopic therapy. UROLOGY 53: 784–789, 1999. © 1999, Elsevier Science Inc. All rights reserved.
S
trictures of the prostatic urethra in adults are iatrogenic and their exact incidence after transurethral or open prostatectomy for benign prostatic hyperplasia is still unknown. In 1977, our original classification of iatrogenic prostatic urethral strictures according to extension and site of scar tissue in the prostatic fossa was reported1: type I strictures, located exclusively at the bladder neck; type II strictures, located in the midportion of the prostatic fossa; and type III strictures, when the whole prostatic fossa is replaced by stricture. Within each category of stricture, distinctive characteristics by ultrasound and radiographic imaging can be obtained. Type I. Fibrous tissue involves the bladder neck only. This is best known as bladder neck contracture. Type I strictures (Fig. 1) often occur after prostatectomy for a small-size adenoma when the From the Urology Department, San Giovanni Hospital; and Urology Department, San Raffaele Hospital, Rome, Italy Reprint requests: Paolo Emiliozzi, M.D., Urology Department, San Giovanni Hospital, via Amba Aradam, Rome 00100, Italy Submitted: September 2, 1998, accepted (with revisions): October 30, 1998
784
© 1999, ELSEVIER SCIENCE INC. ALL RIGHTS RESERVED
hypertrophic fibers of the bladder neck are not completely sectioned. On digital rectal examination (DRE), the prostate is regular. Transrectal ultrasound (TRUS) and urethrogram reveal stricture limited to the bladder neck (Fig. 2 and 3). The prostatic fossa is wide, and the verumontanum is present at urethroscopy. Type II. The stricture is localized to the median part of the prostatic fossa (Fig. 4). The bladder neck is usually wide, and the verumontanum is present. This type of stricture may occur after open transvesical adenomectomy performed on an improper cleavage plane. The cranial portion of the peripheral prostate is removed together with the adenoma, with subsequent development of granulation tissue, which causes a secondary scar. Also, after transurethral resection of the prostate (TURP), infection can delay epithelialization of the prostatic fossa, with overgrowth of fibrous tissue. On DRE, the prostate may be normal or irregular because of prior surgery. Ultrasound and radiologic evidence of this kind of stricture are shown in Figures 5 and 6. On endoscopic examination, the verumontanum is present, and the external 0090-4295/99/$20.00 PII S0090-4295(98)00620-7
FIGURE 1. Anatomic characteristics of type I stricture.
FIGURE 3. Urethrocystogram of type I stricture.
FIGURE 4. Anatomic characteristics of type II stricture. FIGURE 2. TRUS of type I stricture. The stricture is limited to the bladder neck, with a wide prostatic fossa.
sphincter is intact. A block of scar tissue is located at the median part of the prostatic fossa. Voiding often occurs through a small orifice. Type III. The stricture involves the whole prostatic urethra (Fig. 7). The stricture may occur after open suprapubic prostatectomy, when the procedure is performed on an improper periprostatic cleavage plane. Often the whole gland is removed. Bleeding after the operation is usually severe and prolonged. The gland is absent on DRE and is substituted by a block of scar tissue, connecting the bladder neck to the membranous urethra. The verumontanum is completely missing. Scar tissue may involve the proximal membranous urethra, and the external UROLOGY 53 (4), 1999
sphincter is often damaged. Patients are often incontinent after surgery. However, within a few months, urinary flow usually decreases sharply, until complete urinary retention occurs. A block of fibrous tissue involves the bladder neck, extending to the membranous urethra. Images of type III stricture are shown in Figures 8 and 9. MATERIAL AND METHODS From 1972 to 1996, 163 patients with postoperative stricture of the prostatic urethra were treated endoscopically. Eighty-three patients had type I strictures, 57 had type II strictures, and 23 had type III strictures. Inclusion criteria were a minimum follow-up of 1 year and preoperative peak flow below 15 mL/s. A postoperative stricture was diagnosed in 83% of cases within 12 months, in 11% between 12 and 24 months, and in 6% more than 24 months after prostatectomy. One hundred twenty-two patients were 785
FIGURE 7. Anatomic characteristics of type III stricture.
FIGURE 5. TRUS of type II stricture. The bladder neck is opened, and the stricture involves the median part of the prostatic fossa only.
FIGURE 8. TRUS of type III stricture. Prostate is partially replaced by hyperechogenic scar tissue, with a thin lumen inside.
FIGURE 6. Urethrocystogram of type II stricture. evaluable, with a median follow-up of 63 months (range 12 to 239). The median age was 69 years (range 48 to 91). The etiology of the stricture was TURP in 57 cases (47%) and open prostatectomy in 65 cases (53%). TURP was the cause in 30 (51%), 27 (59%), and no patients; open prostatectomy was the cause in 29 (49%), 19 (41%), and 17 (100%) patients with type I, type II, and type III strictures, respectively. All patients underwent preoperative evaluation of the stricture, including DRE, urine culture, and urethrocystogram. 786
TRUS was used after 1981. Preoperative urinary infection was found in 24 patients (19%). The median operating time was 30 minutes (range 10 to 70). Hospitalization ranged from 2 to 8 days (median 3.5). Pathologic analysis of resected tissue always revealed fibrotic reaction and extensive scar, without residual benign prostatic hyperplasia. Postoperative uroflowmetry was routinely performed. TRUS or urethrocystogram were performed when peak flow was less than 15 mL/s. Endoscopic therapy was performed according to two surgical principles. First, the block of scar must be completely incised and split into two halves, with a deep section that reaches healthy tissue (Fig. 10). Second, a bridge of intact mucosa must be preserved between the distal and cranial ends of the resection. The epithelial strip will induce early and multidirectional reepithelialization of the prostatic fossa, inhibiting growth of fibrous tissue (Fig. 11). The procedure begins with cold knife section at the 3- and 9-o’clock positions, preserving intact mucosa at the 6- and 12-o’clock positions. Once the thickness of the scar tissue block is evaluated, the operation continues with a Collings knife.2
TYPE I STRICTURES The first incision at the 3- and 9-o’clock positions is deepened with a Collings knife, until a wide opening of the bladder neck is obtained and healthy tissue is reached. UROLOGY 53 (4), 1999
86% (105 of 122) after a single procedure and 92% (112 of 122) after a second procedure. Recurrent strictures always presented within 1 year after the operation at a median interval of 5 months (range 1 to 12). TYPE I STRICTURES Of 83 patients, 59 were evaluable. The mean age was 69 years (range 48 to 91). Median follow-up was 72 months (range 12 to 215). Good results were obtained in 51 (86%) of 59 patients. Furthermore, 3 patients underwent a successful second endoscopic procedure, for a final success rate of 91% (54 of 59). Postoperative urinary tract infection occurred in 6 patients (10%).
FIGURE 9. Urethrocystogram of type III stricture.
TYPE II STRICTURES The incision at the 3- and 9-o’clock positions is deepened with a Collings knife until the block of scar tissue is completely divided into two halves. The incision should be extended to healthy periprostatic fatty tissue. The upper half of the scar is held upward by its attachments to the pubic bone (puboprostatic ligaments). The lower half remains firmly attached to perirectal tissue and Denonvilliers’ fascia. At the end of the procedure, the prostatic urethra should assume an oval shape. Obstructing excess scar tissue is resected, leaving two strips of healthy mucosa at the 6- and 12-o’clock positions.
TYPE II STRICTURES Of 57 patients, 46 were evaluable. The mean age was 67 years (range 50 to 81). Median follow-up was 51 months (range 12 to 177). Good results were obtained in 43 (93%) of 46 patients. Furthermore, 2 patients underwent a successful second endoscopic procedure, for a final success rate of 98% (45 of 46). Postoperative complications included urinary tract infections in 5 patients (11%) and mild stress incontinence in 1 patient (2%).
In type III strictures, the same endoscopic technique as for type II strictures is performed. All scar tissue must be extensively resected, preserving two strips of healthy mucosa. However, in type III strictures, the prostate is substituted by a block of scar tissue. Particular care must be taken in preserving, as much as possible, residual functioning components of the external sphincter to maintain continence. It is difficult to achieve a complete resection of the scar, which is particularly abundant in these cases, because of complete removal of the prostate gland. An 18 to 20F Foley catheter is left in place for 36 to 48 hours for continuous bladder irrigation. Hydraulic self-dilation3 is started 2 to 4 days postoperatively and is continued for 6 months. This maneuver keeps the prostatic urethra open, preventing healing of the urethra to a narrow caliber.
TYPE III STRICTURES Of 23 patients, 17 were evaluable. The mean age was 71 years (range 58 to 81). Median follow-up was 87 months (range 12 to 239). Good results were obtained in 11 (65%) of 17 patients. Furthermore, 2 patients underwent a successful second endoscopic procedure, for a final success rate of 76% (13 of 17). In 2 patients, a second and a third operation, respectively, failed to relieve the obstruction. Postoperative complications included urinary tract infection in 3 patients (18%), bleeding requiring transfusion in 1 patient (6%), and incontinence in 5 patients (29%). Of the 5 incontinent patients, 4 had been incontinent after prostatectomy and had gradually developed urinary retention before our procedure. Four patients had a recurrent stricture: 2 are fully incontinent, and the urethra, although stenotic, is not completely obstructed. The remaining 2 patients are 76 and 81 years old, and refuse to undergo additional open surgery. They have been treated with an indwelling catheter.
RESULTS
COMMENT
Results were classified as good when peak flow values were higher than 15 mL/s and poor when peak flow values were lower than 15 mL/s and a recurrent stricture was detected. At a median follow-up of 63 months (range 12 to 239), 122 patients were evaluable. The overall success rate was
The posterior urethra is divided into the prostatic and membranous uretha. The endoscopic or surgical treatment of strictures of the membranous urethra has been extensively reported.4,5 Strictures of the prostatic urethra are less common. In children, when the prostate is still soft and can be more
TYPE III STRICTURES
UROLOGY 53 (4), 1999
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FIGURE 11. A strip of preserved mucosa (A) fastens re-epithelialization (B), preventing the growth of scar tissue.
FIGURE 10. Operative technique. The stricture must be completely sectioned into two halves to obtain a good result.
easily injured, they may occur after trauma to the pelvis.6 In adults, the prostate is more firm, and disruption after trauma will occur at the membranous urethra, which is the weakest point. Prostatic urethral strictures can occur after prostatectomy for benign prostatic hyperplasia, performed either by the endoscopic route or transvesical or retropubic approach.7 Type III strictures occur rarely and only after suprapubic prostatectomy. This kind of complication does not occur during retropubic or perineal prostatectomy, when the prostate is under direct visual control. Our classification of prostatic urethral strictures was first published in 1977, and it provides the basis for a clear understanding and proper endoscopic management of this challenging pathologic finding.1 The overall incidence of postoperative strictures of the prostatic urethra is not completely assessed, ranging from 0.86% to 14%.7–9 Some pre788
disposing factors have been suggested in the pathogenesis of type I strictures after surgery of the prostate, including low average weight of the adenoma (12 g) compared with an overall median of 28 g, and the adenoma is usually subcervical, with minimal residual urine.10 Studies based on anatomic specimens show that a large intravesical adenoma often dislodges the fibers of the vesical neck laterally,11 such that these fibers do not play a role in obstruction. Conversely, when the prostate is small with a hypertrophic bladder neck, these fibers are very important. If not completely sectioned, they will produce recurrent obstruction. Robinson and Greene12 have shown in experimental animals that vesical neck contracture can be provoked by extensive electrocoagulation. Perioperative infection, bleeding, and indwelling catheter time are not risk factors for developing a postoperative prostatic urethral stricture. Of note, histologic examination reveals infective changes in 47% of resected strictures.7 In type I strictures, endoscopic treatment is safe and easy to perform. In type II strictures, endoscopy is the preferred option, since open surgery for posterior urethral strictures can be complicated by UROLOGY 53 (4), 1999
severe blood loss of up to 5000 mL.13,14 When our endoscopic treatment is compared with the surgical approach, the mean operating time (30 versus 120 minutes)15 and hospitalization (3.5 versus 25 days)14 are remarkably shorter. The strip of preserved healthy mucosa can spread epithelialization of the resected area, inhibiting early growth of fibrous tissue, which is blocked when covered by epithelium.16 In type III strictures, endoscopy is the best option. In fact, the scar tissue block involves the bladder, the rectal wall, and the membranous urethra, making a retropubic or transpubic approach difficult, with a high morbidity rate expected. The incidence of urinary incontinence is high after treatment of type III strictures because of the impairment of sphinteric fibers at the level of the urogenital diaphragm. In these patients, damage of the external sphincter is due to open prostatectomy on an improper cleavage plane. Incontinence occurs immediately after prostatectomy, but after 2 or 3 months, urinary retention develops because of the growth of reactive tissue. Excision of fibrous tissue restores the status quo of incontinence. With any surgical or endoscopic treatment, it is impossible to recover continence in patients in whom both internal and external sphincters have been damaged by a surgical procedure. In patients with severely damaged sphincters, once the results of the operation is stable (at least 1 year follow-up), implantation of an incontinence prosthesis may be proposed. In patients with type III strictures, open surgery is extremely difficult. The scar extensively involves the bladder neck, the retropubic space, and the membranous urethra. A combined retropubic and perineal approach can provide good exposure. However, even if tubularization of the bladder can be performed, after both urinary sphincters are impaired and with the entire prostatomembranous urethra missing, continence cannot be restored. CONCLUSIONS Posterior urethral strictures are a complex entity, for which the etiology, site, and characteristics play a very important role in deciding the appropriate treatment. Within the limits of a retrospective study, our data support the feasibility and longterm good results of endoscopic treatment for iatrogenic strictures of the prostatic urethra. Urologists must be aware of this uncommon stricture,
UROLOGY 53 (4), 1999
which should not be misdiagnosed as a stricture of the membranous urethra. The long-term results of endoscopic treatment for iatrogenic prostatic urethral strictures are good. The technique is safe and easy to learn for types I and II, but requires a rather long learning curve for type III strictures. The last group is a challenge to the surgeon, with a 30% incontinence rate and a 24% reoperation rate. The alternative treatment is an indwelling catheter or an open procedure with increased morbidity. REFERENCES 1. Pansadoro V: Endoskopische Behandlung von Stenosen der hinteren Harnrohre. Akt Urol 8: 305–309, 1977. 2. Pansadoro V, Scarpone P, and Emiliozzi P: The endoscopic treatment of posterior urethral strictures. 11th World Congress on Endourology and ESWL. J Endourol 7(suppl 1): 111, 1992. 3. Marshall S, Lyon RP, and Olson S: Internal urethrotomy with hydraulic urethral dilatation. J Urol 106: 553–556, 1971. 4. Koraitim MM: The lessons of 145 posttraumatic posterior urethral strictures treated in 17 years. J Urol 153: 63– 66, 1995. 5. Webster GD, and Sihelnik S: The management of strictures of the membranous urethra. J Urol 134: 469 – 471, 1985. 6. Burbige KA: Transpubic-perineal urethral reconstruction in boys using a substitution graft. J Urol 148: 1235–1238, 1992. 7. Flamm J: Zur Diagnostik und Therapie der postoperativen. Verengung der hinteren Harnro¨hre. Z Urol Nephrol 75: 145–149, 1982. 8. Sikafi Z, Butler MR, Lane V, et al: Bladder neck contracture following prostatectomy. Br J Urol 57: 308 –310, 1985. 9. Woodhouse E, Barnes R, Hadley H, et al: Fibrous contracture of bladder neck. Urology 13: 393–394, 1979. 10. Greene LF: Postoperative contracture of vesical neck. AUA Update Series 2: 1–7, 1993. 11. Robinson HP, and Greene LF: Postoperative contracture of vesical neck. I. Review of cases and proposed theory of etiology. J Urol 87: 601– 609, 1962. 12. Robinson HP, and Greene LF: Postoperative contracture of vesical neck. II. Experimental production of contracture in dogs. J Urol 87: 610 – 616, 1962. 13. Lieberman SF, and Barry JM: Retreat from transpubic urethroplasty for obliterated membranous urethral strictures. J Urol 128: 379 –381, 1982. 14. Waterhouse K, Laungani G, and Patil U: The surgical repair of membranous urethral strictures: experience with 105 consecutive cases. J Urol 123: 500 –503, 1980. 15. Chiou RK, Gonzalez R, Ortlip S, et al: Endoscopic treatment of posterior urethral obliteration: long-term followup and comparison with transpubic urethroplasty. J Urol 140: 508 –511, 1988. 16. Weaver RJ: Clinical aspects of urethral regeneration. J Urol 93: 247–249, 1965.
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IATROGENIC PROSTATIC URETHRAL STRICTURES: CLASSIFICATION AND ENDOSCOPIC TREATMENT VITO PANSADORO
AND
PAOLO EMILIOZZI
ABSTRACT Objectives. The treatment of posterior urethral strictures is a controversial subject. For proper treatment, it is important to differentiate between iatrogenic prostatic urethral strictures and post-traumatic membranous urethral strictures. Methods. Iatrogenic strictures of the prostatic urethra have been classified according to location and etiology into three categories: type I, located exclusively at the bladder neck; type II, located in the midportion of the prostatic fossa; and type III, when the whole prostatic fossa is replaced by stricture. From 1970 to 1996, 163 patients with postoperative strictures of the prostatic urethra were treated endoscopically. Results. The results obtained in 122 patients are reported; 41 patients are not evaluable. The median follow-up was 63 months (range 12 to 239). Seven patients required a second endoscopic procedure to attain cure. Good results were achieved in 54 (91%) of 59 patients with type I strictures, in 45 (98%) of 46 patients with type II strictures, and in 13 (76%) of 17 patients with type III strictures. The overall success rate was 92% (112 of 122). Complications occurred in 21 patients (17%), including postoperative urinary tract infection (11%), incontinence (4%), stress incontinence (1%), and severe bleeding (1%). Conclusions. Postoperative strictures of the prostatic urethra must be recognized and can be easily treated with endoscopic therapy. UROLOGY 53: 784–789, 1999. © 1999, Elsevier Science Inc. All rights reserved.
S
trictures of the prostatic urethra in adults are iatrogenic and their exact incidence after transurethral or open prostatectomy for benign prostatic hyperplasia is still unknown. In 1977, our original classification of iatrogenic prostatic urethral strictures according to extension and site of scar tissue in the prostatic fossa was reported1: type I strictures, located exclusively at the bladder neck; type II strictures, located in the midportion of the prostatic fossa; and type III strictures, when the whole prostatic fossa is replaced by stricture. Within each category of stricture, distinctive characteristics by ultrasound and radiographic imaging can be obtained. Type I. Fibrous tissue involves the bladder neck only. This is best known as bladder neck contracture. Type I strictures (Fig. 1) often occur after prostatectomy for a small-size adenoma when the From the Urology Department, San Giovanni Hospital; and Urology Department, San Raffaele Hospital, Rome, Italy Reprint requests: Paolo Emiliozzi, M.D., Urology Department, San Giovanni Hospital, via Amba Aradam, Rome 00100, Italy Submitted: September 2, 1998, accepted (with revisions): October 30, 1998
784
© 1999, ELSEVIER SCIENCE INC. ALL RIGHTS RESERVED
hypertrophic fibers of the bladder neck are not completely sectioned. On digital rectal examination (DRE), the prostate is regular. Transrectal ultrasound (TRUS) and urethrogram reveal stricture limited to the bladder neck (Fig. 2 and 3). The prostatic fossa is wide, and the verumontanum is present at urethroscopy. Type II. The stricture is localized to the median part of the prostatic fossa (Fig. 4). The bladder neck is usually wide, and the verumontanum is present. This type of stricture may occur after open transvesical adenomectomy performed on an improper cleavage plane. The cranial portion of the peripheral prostate is removed together with the adenoma, with subsequent development of granulation tissue, which causes a secondary scar. Also, after transurethral resection of the prostate (TURP), infection can delay epithelialization of the prostatic fossa, with overgrowth of fibrous tissue. On DRE, the prostate may be normal or irregular because of prior surgery. Ultrasound and radiologic evidence of this kind of stricture are shown in Figures 5 and 6. On endoscopic examination, the verumontanum is present, and the external 0090-4295/99/$20.00 PII S0090-4295(98)00620-7
FIGURE 1. Anatomic characteristics of type I stricture.
FIGURE 3. Urethrocystogram of type I stricture.
FIGURE 4. Anatomic characteristics of type II stricture. FIGURE 2. TRUS of type I stricture. The stricture is limited to the bladder neck, with a wide prostatic fossa.
sphincter is intact. A block of scar tissue is located at the median part of the prostatic fossa. Voiding often occurs through a small orifice. Type III. The stricture involves the whole prostatic urethra (Fig. 7). The stricture may occur after open suprapubic prostatectomy, when the procedure is performed on an improper periprostatic cleavage plane. Often the whole gland is removed. Bleeding after the operation is usually severe and prolonged. The gland is absent on DRE and is substituted by a block of scar tissue, connecting the bladder neck to the membranous urethra. The verumontanum is completely missing. Scar tissue may involve the proximal membranous urethra, and the external UROLOGY 53 (4), 1999
sphincter is often damaged. Patients are often incontinent after surgery. However, within a few months, urinary flow usually decreases sharply, until complete urinary retention occurs. A block of fibrous tissue involves the bladder neck, extending to the membranous urethra. Images of type III stricture are shown in Figures 8 and 9. MATERIAL AND METHODS From 1972 to 1996, 163 patients with postoperative stricture of the prostatic urethra were treated endoscopically. Eighty-three patients had type I strictures, 57 had type II strictures, and 23 had type III strictures. Inclusion criteria were a minimum follow-up of 1 year and preoperative peak flow below 15 mL/s. A postoperative stricture was diagnosed in 83% of cases within 12 months, in 11% between 12 and 24 months, and in 6% more than 24 months after prostatectomy. One hundred twenty-two patients were 785
FIGURE 7. Anatomic characteristics of type III stricture.
FIGURE 5. TRUS of type II stricture. The bladder neck is opened, and the stricture involves the median part of the prostatic fossa only.
FIGURE 8. TRUS of type III stricture. Prostate is partially replaced by hyperechogenic scar tissue, with a thin lumen inside.
FIGURE 6. Urethrocystogram of type II stricture. evaluable, with a median follow-up of 63 months (range 12 to 239). The median age was 69 years (range 48 to 91). The etiology of the stricture was TURP in 57 cases (47%) and open prostatectomy in 65 cases (53%). TURP was the cause in 30 (51%), 27 (59%), and no patients; open prostatectomy was the cause in 29 (49%), 19 (41%), and 17 (100%) patients with type I, type II, and type III strictures, respectively. All patients underwent preoperative evaluation of the stricture, including DRE, urine culture, and urethrocystogram. 786
TRUS was used after 1981. Preoperative urinary infection was found in 24 patients (19%). The median operating time was 30 minutes (range 10 to 70). Hospitalization ranged from 2 to 8 days (median 3.5). Pathologic analysis of resected tissue always revealed fibrotic reaction and extensive scar, without residual benign prostatic hyperplasia. Postoperative uroflowmetry was routinely performed. TRUS or urethrocystogram were performed when peak flow was less than 15 mL/s. Endoscopic therapy was performed according to two surgical principles. First, the block of scar must be completely incised and split into two halves, with a deep section that reaches healthy tissue (Fig. 10). Second, a bridge of intact mucosa must be preserved between the distal and cranial ends of the resection. The epithelial strip will induce early and multidirectional reepithelialization of the prostatic fossa, inhibiting growth of fibrous tissue (Fig. 11). The procedure begins with cold knife section at the 3- and 9-o’clock positions, preserving intact mucosa at the 6- and 12-o’clock positions. Once the thickness of the scar tissue block is evaluated, the operation continues with a Collings knife.2
TYPE I STRICTURES The first incision at the 3- and 9-o’clock positions is deepened with a Collings knife, until a wide opening of the bladder neck is obtained and healthy tissue is reached. UROLOGY 53 (4), 1999
86% (105 of 122) after a single procedure and 92% (112 of 122) after a second procedure. Recurrent strictures always presented within 1 year after the operation at a median interval of 5 months (range 1 to 12). TYPE I STRICTURES Of 83 patients, 59 were evaluable. The mean age was 69 years (range 48 to 91). Median follow-up was 72 months (range 12 to 215). Good results were obtained in 51 (86%) of 59 patients. Furthermore, 3 patients underwent a successful second endoscopic procedure, for a final success rate of 91% (54 of 59). Postoperative urinary tract infection occurred in 6 patients (10%).
FIGURE 9. Urethrocystogram of type III stricture.
TYPE II STRICTURES The incision at the 3- and 9-o’clock positions is deepened with a Collings knife until the block of scar tissue is completely divided into two halves. The incision should be extended to healthy periprostatic fatty tissue. The upper half of the scar is held upward by its attachments to the pubic bone (puboprostatic ligaments). The lower half remains firmly attached to perirectal tissue and Denonvilliers’ fascia. At the end of the procedure, the prostatic urethra should assume an oval shape. Obstructing excess scar tissue is resected, leaving two strips of healthy mucosa at the 6- and 12-o’clock positions.
TYPE II STRICTURES Of 57 patients, 46 were evaluable. The mean age was 67 years (range 50 to 81). Median follow-up was 51 months (range 12 to 177). Good results were obtained in 43 (93%) of 46 patients. Furthermore, 2 patients underwent a successful second endoscopic procedure, for a final success rate of 98% (45 of 46). Postoperative complications included urinary tract infections in 5 patients (11%) and mild stress incontinence in 1 patient (2%).
In type III strictures, the same endoscopic technique as for type II strictures is performed. All scar tissue must be extensively resected, preserving two strips of healthy mucosa. However, in type III strictures, the prostate is substituted by a block of scar tissue. Particular care must be taken in preserving, as much as possible, residual functioning components of the external sphincter to maintain continence. It is difficult to achieve a complete resection of the scar, which is particularly abundant in these cases, because of complete removal of the prostate gland. An 18 to 20F Foley catheter is left in place for 36 to 48 hours for continuous bladder irrigation. Hydraulic self-dilation3 is started 2 to 4 days postoperatively and is continued for 6 months. This maneuver keeps the prostatic urethra open, preventing healing of the urethra to a narrow caliber.
TYPE III STRICTURES Of 23 patients, 17 were evaluable. The mean age was 71 years (range 58 to 81). Median follow-up was 87 months (range 12 to 239). Good results were obtained in 11 (65%) of 17 patients. Furthermore, 2 patients underwent a successful second endoscopic procedure, for a final success rate of 76% (13 of 17). In 2 patients, a second and a third operation, respectively, failed to relieve the obstruction. Postoperative complications included urinary tract infection in 3 patients (18%), bleeding requiring transfusion in 1 patient (6%), and incontinence in 5 patients (29%). Of the 5 incontinent patients, 4 had been incontinent after prostatectomy and had gradually developed urinary retention before our procedure. Four patients had a recurrent stricture: 2 are fully incontinent, and the urethra, although stenotic, is not completely obstructed. The remaining 2 patients are 76 and 81 years old, and refuse to undergo additional open surgery. They have been treated with an indwelling catheter.
RESULTS
COMMENT
Results were classified as good when peak flow values were higher than 15 mL/s and poor when peak flow values were lower than 15 mL/s and a recurrent stricture was detected. At a median follow-up of 63 months (range 12 to 239), 122 patients were evaluable. The overall success rate was
The posterior urethra is divided into the prostatic and membranous uretha. The endoscopic or surgical treatment of strictures of the membranous urethra has been extensively reported.4,5 Strictures of the prostatic urethra are less common. In children, when the prostate is still soft and can be more
TYPE III STRICTURES
UROLOGY 53 (4), 1999
787
FIGURE 11. A strip of preserved mucosa (A) fastens re-epithelialization (B), preventing the growth of scar tissue.
FIGURE 10. Operative technique. The stricture must be completely sectioned into two halves to obtain a good result.
easily injured, they may occur after trauma to the pelvis.6 In adults, the prostate is more firm, and disruption after trauma will occur at the membranous urethra, which is the weakest point. Prostatic urethral strictures can occur after prostatectomy for benign prostatic hyperplasia, performed either by the endoscopic route or transvesical or retropubic approach.7 Type III strictures occur rarely and only after suprapubic prostatectomy. This kind of complication does not occur during retropubic or perineal prostatectomy, when the prostate is under direct visual control. Our classification of prostatic urethral strictures was first published in 1977, and it provides the basis for a clear understanding and proper endoscopic management of this challenging pathologic finding.1 The overall incidence of postoperative strictures of the prostatic urethra is not completely assessed, ranging from 0.86% to 14%.7–9 Some pre788
disposing factors have been suggested in the pathogenesis of type I strictures after surgery of the prostate, including low average weight of the adenoma (12 g) compared with an overall median of 28 g, and the adenoma is usually subcervical, with minimal residual urine.10 Studies based on anatomic specimens show that a large intravesical adenoma often dislodges the fibers of the vesical neck laterally,11 such that these fibers do not play a role in obstruction. Conversely, when the prostate is small with a hypertrophic bladder neck, these fibers are very important. If not completely sectioned, they will produce recurrent obstruction. Robinson and Greene12 have shown in experimental animals that vesical neck contracture can be provoked by extensive electrocoagulation. Perioperative infection, bleeding, and indwelling catheter time are not risk factors for developing a postoperative prostatic urethral stricture. Of note, histologic examination reveals infective changes in 47% of resected strictures.7 In type I strictures, endoscopic treatment is safe and easy to perform. In type II strictures, endoscopy is the preferred option, since open surgery for posterior urethral strictures can be complicated by UROLOGY 53 (4), 1999
severe blood loss of up to 5000 mL.13,14 When our endoscopic treatment is compared with the surgical approach, the mean operating time (30 versus 120 minutes)15 and hospitalization (3.5 versus 25 days)14 are remarkably shorter. The strip of preserved healthy mucosa can spread epithelialization of the resected area, inhibiting early growth of fibrous tissue, which is blocked when covered by epithelium.16 In type III strictures, endoscopy is the best option. In fact, the scar tissue block involves the bladder, the rectal wall, and the membranous urethra, making a retropubic or transpubic approach difficult, with a high morbidity rate expected. The incidence of urinary incontinence is high after treatment of type III strictures because of the impairment of sphinteric fibers at the level of the urogenital diaphragm. In these patients, damage of the external sphincter is due to open prostatectomy on an improper cleavage plane. Incontinence occurs immediately after prostatectomy, but after 2 or 3 months, urinary retention develops because of the growth of reactive tissue. Excision of fibrous tissue restores the status quo of incontinence. With any surgical or endoscopic treatment, it is impossible to recover continence in patients in whom both internal and external sphincters have been damaged by a surgical procedure. In patients with severely damaged sphincters, once the results of the operation is stable (at least 1 year follow-up), implantation of an incontinence prosthesis may be proposed. In patients with type III strictures, open surgery is extremely difficult. The scar extensively involves the bladder neck, the retropubic space, and the membranous urethra. A combined retropubic and perineal approach can provide good exposure. However, even if tubularization of the bladder can be performed, after both urinary sphincters are impaired and with the entire prostatomembranous urethra missing, continence cannot be restored. CONCLUSIONS Posterior urethral strictures are a complex entity, for which the etiology, site, and characteristics play a very important role in deciding the appropriate treatment. Within the limits of a retrospective study, our data support the feasibility and longterm good results of endoscopic treatment for iatrogenic strictures of the prostatic urethra. Urologists must be aware of this uncommon stricture,
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which should not be misdiagnosed as a stricture of the membranous urethra. The long-term results of endoscopic treatment for iatrogenic prostatic urethral strictures are good. The technique is safe and easy to learn for types I and II, but requires a rather long learning curve for type III strictures. The last group is a challenge to the surgeon, with a 30% incontinence rate and a 24% reoperation rate. The alternative treatment is an indwelling catheter or an open procedure with increased morbidity. REFERENCES 1. Pansadoro V: Endoskopische Behandlung von Stenosen der hinteren Harnrohre. Akt Urol 8: 305–309, 1977. 2. Pansadoro V, Scarpone P, and Emiliozzi P: The endoscopic treatment of posterior urethral strictures. 11th World Congress on Endourology and ESWL. J Endourol 7(suppl 1): 111, 1992. 3. Marshall S, Lyon RP, and Olson S: Internal urethrotomy with hydraulic urethral dilatation. J Urol 106: 553–556, 1971. 4. Koraitim MM: The lessons of 145 posttraumatic posterior urethral strictures treated in 17 years. J Urol 153: 63– 66, 1995. 5. Webster GD, and Sihelnik S: The management of strictures of the membranous urethra. J Urol 134: 469 – 471, 1985. 6. Burbige KA: Transpubic-perineal urethral reconstruction in boys using a substitution graft. J Urol 148: 1235–1238, 1992. 7. Flamm J: Zur Diagnostik und Therapie der postoperativen. Verengung der hinteren Harnro¨hre. Z Urol Nephrol 75: 145–149, 1982. 8. Sikafi Z, Butler MR, Lane V, et al: Bladder neck contracture following prostatectomy. Br J Urol 57: 308 –310, 1985. 9. Woodhouse E, Barnes R, Hadley H, et al: Fibrous contracture of bladder neck. Urology 13: 393–394, 1979. 10. Greene LF: Postoperative contracture of vesical neck. AUA Update Series 2: 1–7, 1993. 11. Robinson HP, and Greene LF: Postoperative contracture of vesical neck. I. Review of cases and proposed theory of etiology. J Urol 87: 601– 609, 1962. 12. Robinson HP, and Greene LF: Postoperative contracture of vesical neck. II. Experimental production of contracture in dogs. J Urol 87: 610 – 616, 1962. 13. Lieberman SF, and Barry JM: Retreat from transpubic urethroplasty for obliterated membranous urethral strictures. J Urol 128: 379 –381, 1982. 14. Waterhouse K, Laungani G, and Patil U: The surgical repair of membranous urethral strictures: experience with 105 consecutive cases. J Urol 123: 500 –503, 1980. 15. Chiou RK, Gonzalez R, Ortlip S, et al: Endoscopic treatment of posterior urethral obliteration: long-term followup and comparison with transpubic urethroplasty. J Urol 140: 508 –511, 1988. 16. Weaver RJ: Clinical aspects of urethral regeneration. J Urol 93: 247–249, 1965.
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