Twenty-four patients with internal urinary diversion following total bladder ablation underwent colonoscopic control of the uretero-enteric anastomoses. The techniques performed were: rectal bladder with colostomy according to Mauclaire (11 patients); rectal bladder with abdomino-perineal pull-through according to Heitz-Boyer/Hovelacque (6); ureterosigmoidostomy (7). The uretero-enteric anastomoses were divided into 3 categories according to the colonoscopic appearance: "nipple-like", nearly flat and flat anastomosis. Urographic examinations were carried out in all patients and the results demonstrated that the "nipple-like" anastomosis was the most successful for the preservation of upper urinary tract integrity.