Bladder calculi account for 5% of all urinary calculi. Stone composition is influenced by the pH and the concentration of the urine, and most calculi are of mixed composition. Nutritional deficiencies, dehydration, diarrhea, and infection increase the incidence of bladder stone formation in Africa and the Middle East. Uric acid and urate stones predominate in Europe, and calcium oxalate is the most prevalent composition in the United States.
Although most bladder stones are asymptomatic, symptoms when present include hematuria, recurrent urinary tract infections (UTIs), painful voiding, and irritative lower urinary tract symptoms. Rarely, the calculi can be large enough to cause obstruction with subsequent bilateral hydroureteronephrosis.
Bladder stones are typically the result of a primary underlying etiology, and workup and treatment are essential to avoid recurrent calculi. In adults, causes include bladder outlet obstruction, urethral stricture, pelvic organ prolapse, neurogenic voiding dysfunction, infection, and foreign bodies (particularly in women, including sutures, synthetic tapes, or mesh). Use of intestine in the urinary tract for augmentation or neobladder is associated with increased mucus production, urinary stasis, and recurrent UTIs, which predispose to bladder calculi. In children, predisposing factors include anatomic abnormalities such as posterior urethral valves, voiding dysfunction, and vesicoureteral reflux.
Bladder stones can be identified with radiography, ultrasonography, computed tomography, or cystoscopy. However, approximately 50% of stones can be missed on plain films. Cystoscopy is considered the gold standard and has the additional benefit of helping with surgical planning to identify prostatic hypertrophy, bladder diverticula, urethral strictures, and other anatomic abnormalities.
Urodynamics to assess for the underlying etiology are indicated for all patients with lower urinary tract symptoms, incontinence, or neurologic disease. This aids with surgical planning to address both the stones and the predisposing factors. Findings may change the surgical approach in the case of benign prostatic hyperplasia, diverticula, urethral stricture, or foreign body.
For smaller stones, treatment with transurethral cystolitholapaxy or percutaneous endoscopic cystolitholapaxy is typically indicated. For larger stones or stone burden greater than 4 to 6 cm, hard stones; failure of an endoscopic approach; or the need for concomitant open surgery including open simple prostatectomy or diverticulectomy, open suprapubic cystolithotomy is recommended.
Preoperative workup includes cystoscopy, urodynamics if indicated, and urinalysis with urine culture. It is important that any UTI is treated with culture-specific antibiotics before the surgical procedure.
Patients are placed in the supine position. The penis and urethra are prepped in the operative field, and a large Foley catheter is placed. A midline lower abdominal or Pfannenstiel incision is made ( Fig. 53.1, A ). The muscles are split in the midline, the fascia divided, and the space of Retzius entered and developed with care to avoid entering the abdomen ( Fig. 53.1, B ). A retractor can be placed at this time if desired.