Bladder diverticula are the result of herniation of the bladder mucosa through the detrusor wall. Because of the lack of muscularis tissue around the diverticula, they usually empty poorly or incompletely. Urinary stasis, inflammation, and resultant infection can occur. A fibrous pseudocapsule often encases the bladder diverticulum. Inflammation also creates an environment at risk for malignancy. Bladder cancer within any diverticulum has a poorer prognosis because of the lack of muscularis, which can result in early tumor infiltration.
Many diverticula are often asymptomatic, and most are never diagnosed. Typical presenting symptoms include hematuria, infection, and lower urinary tract symptoms. Bladder diverticula are either congenital or acquired and can occur at any age but are usually detected in middle or older age. Men are more commonly affected than women.
Congenital diverticula are commonly a consequence of an inherent detrusor weakness. They are typically solitary, lateral, and posterior to the ureteral orifice and occur without evidence of outflow obstruction. They can enlarge and encroach upon the ureteral orifice and cause either ureteral obstruction or reflux. Surgical intervention may be required in cases of recurrent infections, vesicoureteral reflux, ureteral obstruction, or bladder neck obstruction.
Acquired diverticula commonly occur in patients with bladder outlet obstruction, neurogenic voiding dysfunction, or impaired bladder compliance. Significant bladder trabeculations and hypertrophied detrusor muscles increase the propensity for diverticula to occur. The increased intravesical pressure causes mucosa to protrude between hypertrophied muscle bundles.
Asymptomatic patients may be followed conservatively with urine cultures, urine cytology, and endoscopic surveillance. Symptomatic patients may require surgical intervention. Complications of bladder diverticula include persistent infection, stone formation, ureteral obstruction, and urinary retention. Traditionally surgical repairs have been done with open procedures. In recent years, laparoscopic and robotic diverticulectomy repairs have become more common.
A voiding cystourethrogram is recommended to assess the number, size, location, concurrent reflux, and emptying of the diverticulum with voiding. Cystourethroscopy is also advisable to determine location of the ureteral orifices in association with the diverticulum and to assess for mucosal abnormalities. If the ureteral orifices are involved, ureteral reimplantation at the time of diverticulectomy may be needed. Upper tract imaging with intravenous pyelography, ultrasonography, or computed tomography urography should be performed assessing for hydronephrosis or ureteral obstruction.
The underlying abnormality causing the diverticula should be addressed either before or during surgical treatment of the diverticula. In some cases, treatment of the underlying urologic abnormality will result in symptom resolution, and no further treatment is needed for the diverticula. Urodynamics should be considered to aid in identification of any underlying functional abnormality.
Patient should have a clean urinalysis and urine culture before any surgical procedure or placed on appropriate antibiotics preoperatively. Preoperative medical clearance for surgery is performed to minimize surgical risk.
Combined Intravesical and Extravesical Approach
The combined approach is ideal for patients with a larger diverticulum or fibrosis or inflammation surrounding the diverticula.
Place the patient in the supine position with the pelvis over the kidney rest and in slight extension. Prep and drape the penis and urethra into the field. Insert a 22-Fr Foley catheter and partially fill the bladder. Cover the penis and urethra and catheter with a towel.
Make a lower midline extraperitoneal incision ( Fig. 52.1, A )
Incise the linea alba. Enter the abdomen between the recti and separate them. Divide the transversalis fascia with scissors and move laterally. Push the peritoneal fold upward, revealing the perivesical fact. Place a self-retaining retractor, such as a Bookwalter retractor, for optimal exposure. Through the Foley catheter, fill the bladder to capacity with sterile water. Develop the retropubic space ( Fig. 52.1, B ).
Place two stay sutures in the detrusor wall well above the pubic symphysis. Ensure that there is adequate suction in hand. Incise the detrusor muscle in a vertical fashion between the stay sutures using electrocautery. Use the suction to remove the excess irrigation.
Adjust the retractors as necessary to reveal the diverticulum and ureteral orifices. Place ureteral catheters to aid in avoiding ureteral injury if necessary.
Locate and incise the mucosa at the diverticula neck circumferentially with electrocautery. Place a finger in the diverticulum ( Fig. 52.2, A ). Using a finger for traction, bring the diverticula neck outside the bladder so the diverticulum can be palpated anteriorly through the wound. Dissect the overlying tissue to expose the anterior portion the diverticula neck. Dissect the perivesical tissue away from the bladder wall down to the palpable fingertip ( Fig. 52.2, B ). Incise the anterior portion of the diverticular neck around the finger ( Fig. 52.3 ).
Use fine Allis clamps to grasp the urothelium edges and progressively dissect the neck of the diverticulum circumferentially from the bladder ( Fig. 52.4 ).
After the diverticular neck has been freed from the mucosa, mobilize and dissect the walls of the diverticulum from the capsule until it can be completely removed ( Fig. 52.5 ). These steps are carried out carefully to make identification of the mucosa and detrusor layers easier at the time of closure of the bladder defect. When the diverticulum is densely adherent to the capsule, portions may be left in situ. There is no need to leave a drain in the diverticular cavity.
Close the bladder wall at the diverticular mouth in two layers, ensuring closure of the muscularis serosal layer to prevent recurrent diverticulum ( Fig. 52.6 ).
If needed, place a suprapubic catheter or a large Foley catheter in the bladder with a cystotomy in through the abdominal wall. Suture in place with the bladder with an absorbable purse-string suture secured to the skin ( Fig. 52.7 ).