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dissection; this will decrease urine leaking via the fistula tract and improve visualization during repair. Urethral catheter is also placed, if possible, to allow palpation of the urethra during the perineal dissection.

The incision is made in the shape of an inverted U, with the apex just above the level of the anal sphincter and extending to a location just inside the ischial tuberosities bilaterally (Fig. 15-3). A midline vertical incision may be added for increased exposure, in the case of excess soft tissue, or for further access to the anterior urethra in cases where posterior urethroplasty is necessary.

FIGURE 15-3 Male perineum with inverted-U incision (dotted line) extending

between the ischial tuberosities.

Initial Dissection

After deepening the incision, enter the ischiorectal fossa bilaterally and develop these spaces using blunt dissection. Carefully proceed to dissect the plane between the rectum posteriorly and the urethra, prostate, and bladder anteriorly. This is started through the area of the central tendon between the bulbospongiosus muscle and the anal sphincter. Once beyond the anal sphincter, the dissection is carried onto the anterior rectal wall and the perirectal fat laterally.

Follow the anterior surface of the rectum until encountering the fistula tract. Identification of the plane may be difficult due to prior surgical scarring or exposure to radiation and other ablative energy sources, so periodic rectal examinations may be required to proceed to confirm the site of the fistula and avoid entering the rectum too soon. A handheld retractor with fiberoptic lighting may be needed for improved visualization. An assistant can stand at the patient’s side (behind one leg) to hold the retractor, which will also provide anterior traction. Posterior countertraction can be provided with a handheld malleable retractor on the rectum. After entering the fistula tract, circumferentially transect the fistula and continue to dissect the plane further proximally. Once through the fistula, the dissection is oriented a little more inferiorly to follow the natural course of the rectum and avoid inadvertent entry into the bladder. Perirectal and perivesical fat is usually encountered, and this is a safe plane to dissect within as one proceeds more proximally (Fig. 15-4). The dissection should be continued, and the rectum mobilized to allow tensionfree closure with adequate space for the gracilis flap to completely cover the repair.

FIGURE 15-4 A. Dissection between the rectum and the urinary tract. A handheld

retractor is held anteriorly to provide both countertraction and additional light. The fistula tract has been transected circumferentially, and perirectal fat is seen beyond the fistula tract. Defects in the prostatic urethra and the rectum can be seen. B. An Allis clamp can be used to provide traction for the remaining proximal rectal mobilization and dissection and to demonstrate approximation for transverse rectal closure.

Rectal Closure

Once the space between the urinary tract and the rectum has been developed, proceed with closure of the rectum and primary closure of the urethral defect if possible. Rectal closure should be performed in two layers and done in a transverse manner if the anatomy allows. The first layer can be done with fullthickness bites utilizing interrupted 3-0 absorbable suture such as Vicryl or polydioxanone (PDS). A second interrupted layer with 3-0 suture should then be performed with a braided polyester suture such as Ethibond, imbricating tissue over the first layer of closure.

Urethral Closure

If the urethral defect can be closed primarily, do so with interrupted absorbable suture such as 3-0 PDS. If needed, flexible cystoscopy may be performed to confirm fistula location and to make sure closure of the defect has not resulted in narrowing of the urethral lumen. If the urethral defect is too large or fixed for primary closure, a buccal mucosa graft may be required for closure. Once the buccal mucosa graft has been harvested, thin the graft by carefully removing attached tissue to optimize graft take. With the mucosal surface of the graft facing the urethral lumen, patch the urethral defect using absorbable monofilament suture, preferably 4-0 PDS (Fig. 15-5A).

FIGURE 15-5 Anastomotic urethroplasty for coexisting posterior urethral stricture. A.

Anastomotic sutures placed into distal prostatic urethra following excision of the fistula and associated fibrotic stricture. B. Bulbar urethra brought to level of anastomosis without tension. C. Completed anastomosis. The rectal closure sutures are seen posteriorly. The space between the rectal closure and urethral anastomosis will be filled with a gracilis muscle interposition.

If there is an associated moderate stricture of the membranous urethra, urethrotomy incision can be made from the fistula through the strictured segment, with a longer buccal mucosa graft then used to close the urethral defect and augment the stricture.

To check for a water-tight closure, gently fill the urethra in retrograde manner with normal saline. Repair any large leaks with interrupted sutures as needed. Once the urethral repair is completed, replace a 16Fr or 18Fr soft silicone Foley catheter.

Posterior Urethroplasty

For cases with coexisting posterior urethral stricture or obliteration, posterior urethroplasty with primary anastomosis can be performed in select cases. Presence of the stricture will be known preoperatively following imaging and examination under anesthesia, so at the time of incision, a vertical midline incision may be added to the inverted-U incision. Carry the midline incision down to the bulbospongiosus muscle with electrocautery, then divide the bulbospongiosus muscle and mobilize the urethra circumferentially with Metzenbaum scissors. The urethra can be mobilized distally to the level of the penile suspensory ligament. Using a catheter or Bougie to identify the distal extent of the stricture, transect the urethra and make a dorsal urethrotomy extending approximately 1 cm into healthy urethra. Dissect the scarred membranous or prostatic urethra until encountering a sufficient lumen for urethral anastomosis. This will require excision of a segment of the urethra and possibly a portion of the prostate until reaching tissue sufficiently healthy to hold a suture. In cases of complete obliteration, use of a curved metal sound or flexible cystoscope passed into the bladder neck and posterior urethra via the suprapubic catheter tract provides a palpable target for this dissection. Calibrate both the proximal urethra or bladder neck and the transected urethra to achieve a goal lumen of 26-30Fr. To allow for a tension-free anastomosis, adjunct maneuvers may be required to gain urethral length. The corpora cavernosa may be separated by sharply dissecting between the two erectile bodies, starting with a scalpel and continuing with tenotomy scissors. Separate the corpora cavernosa until the pubic symphysis is palpable. If further urethral length is required for anastomosis, suture ligate the

dorsal vein and perform an inferior pubectomy. Perform an anastomotic urethroplasty with a series of interrupted 3-0 PDS sutures, leaving the knots outside the lumen. Between six and eight sutures are generally sufficient (Fig. 15-5).

Gracilis Muscle Interposition

Following closure of the urethral and rectal defects, interposition of wellvascularized tissue is the final key component of complex fistula repair. Lower the legs into a standard lithotomy position. Cut back the drape along the selected thigh and secure to the skin with a stapler (Fig. 15-6A).

FIGURE 15-6 Gracilis muscle interposition. A. Harvest of left gracilis muscle with

incision just below the level of the mid-thigh. After transecting the gracilis tendon, the muscle will be passed through a subcutaneous tunnel to the perineum. B. Vascular pedicles of the gracilis muscle. The primary pedicle is located approximately 9 cm from the pubic tubercle; all remaining secondary pedicles should be ligated to mobilize the muscle

after ensuring a good arterial wave of the primary pedicle with Doppler ultrasound. C. Gracilis muscle passed into the perineal wound through a large subcutaneous tunnel over the ipsilateral ischiopubic ramus. D. Schematic illustration of gracilis muscle secured beyond the level of both rectal and urethral closures. Note that the muscle reaches a level posterior to the bladder and proximal to both the urethral and rectal repairs. E. Completed rectal and urethral closures with interposed gracilis muscle. The muscle provides good bulk to fill the space created by the dissection and separate the closures.

Make an incision over the inner thigh along the course of the gracilis muscle. The distal tendon of the muscle can generally be palpated at the knee as a thick cord, and the incision can end a few centimeters proximal to the tendon. Deepen the incision with electrocautery and identify the muscle. Dissect the fascia off the muscle distally to identify the tendon and, therefore, positively identify the gracilis, then continue the dissection proximally. Preserve the vascular pedicles to the muscle during dissection (Fig. 156B). The primary pedicle is located approximately 9 cm from the pubic tubercle. Use a Doppler ultrasound probe to ensure adequate arterial flow at the primary pedicle before ligating any secondary pedicles to complete the muscle mobilization. Free the fascial tissue off the muscle to the level of the primary pedicle to maximize its ability to rotate into position. Divide the distal tendon with electrocautery. With a combination of blunt and sharp dissection, create a wide subcutaneous tunnel over the ischiopubic ramus between the perineal and thigh incisions. Rotate the gracilis on the primary pedicle and pass the muscle into the perineum (Fig. 15-6C). Place a series of interrupted 3-0 PDS sutures at the distal extent of the perineal dissection, in order to anchor the muscle flap beyond the repaired rectal and urethral defects. Pass these sutures through the appropriate side of the muscle and tie them down to secure the muscle in place proximally (Fig. 15-6D). The result should be bulky muscle filling the perineal dissection (Fig. 15-6E), which can then be further secured into position with interrupted 3-0 Vicryl sutures to the perineal musculature and fat laterally. Before closing the thigh wound, place a closed suction drain exiting distally, and leave the drain in the bed of the gracilis muscle. Loosely reapproximate muscular fascia with a series of interrupted 3-0 Vicryl sutures.

Close the subcutaneous tissue with interrupted 3-0 Vicryl sutures with knots buried before closing the skin with a stapler.

Wound Closure

Leave a Penrose drain in the perineal wound exiting one corner of the inverted-U incision. Following copious irrigation of the wound, use absorbable suture to close dead space with perineal fat. Close the bulbospongiosus muscle with interrupted 3-0 Vicryl if it was opened to mobilize the urethra. Use running 3-0 Vicryl to close Colles fascia and approximate all wound edges. Close skin with running 4-0 Vicryl.

PEARLS AND PITFALLS

Be sure to extend the initial dissection beyond the fistula to a level under the bladder. This allows for sufficient mobility of the rectum for tension-free closure and provides space for anchoring the gracilis muscle. This ensures that healthy well-vascularized tissue will completely separate the urethral and rectal closures. After dissecting through the fistula tract, it is critical to orient further proximal dissection a little posteriorly, using the perirectal fat as a guide, as further dissection straight in through the perineal tissues may lead to injury of the posterior bladder. Transverse closure of the rectal defect is preferred to longitudinal closure, so as to avoid narrowing of the rectal lumen. However, longitudinal closure may be required in some cases based on patient anatomy. When creating the tunnel for the gracilis muscle, aim for a width of four fingerbreadths. This allows for postoperative swelling of the muscle without compromising its blood supply.

Postoperative Care

Following a gracilis muscle interposition, keep the patient on postoperative bed rest for a period of 48-72 hours. Use appropriate pharmacologic deep vein thrombosis prophylaxis. When ready for hospital discharge, urinary drainage can be achieved with either a urethral catheter or suprapubic catheter with the urethral catheter plugged. Voiding cystourethrogram is obtained 5-6 weeks following surgery, and urinary catheters are removed if well healed. If there is significant extravasation of contrast, suprapubic catheter drainage is continued, and the patient is restudied a few weeks later. Gastrografin enema is obtained 5-6 months postoperatively to document healing, followed by stoma reversal shortly thereafter.