Colovesical fistulas.

Colovesical fistulas were identified in 42 patients. Diverticulitis was the underlying cause in 40 per cent of the patients. Carcinoma of the colon or cervix caused 33 per cent of the fistulas. Cystoscopy was the most effective procedure in diagnosing the fistulas. Surgical therapy had to be individualized to the patient's condition. Fistulas secondary to radiation were associated with a high complication rate.