Rectodynamic and radiological assessment in modified mainz pouch II cases

To evaluate the radiologic findings and to measure the pressure changes in a modified sigmoidorectal pouch (Mainz pouch II procedure).

A total of 26 patients who had a radical cystectomy because of muscle-invasive bladder tumor underwent a Mainz pouch II procedure between 1993 and 1998. The differences from the original definition was a reverse ureteral anastomosis and a detubularized segment at least 30 cm in length. In all cases, sigmoidoscopy was done and sigmoidal pressure and capacity were measured preoperatively and at the 3rd and 6th months postoperatively besides the colon X-rays. The 24-hour pouch pressure changes called 'natural pouch pressure' was measured using a handmade system with a central venous pressure (CVP) manometer at the 3rd month postoperatively.

Preoperative colon X-rays showed a passage of opaque substance through the descending colon at an average volume of 150 ml (average sigma capacity), whereas postoperative anteroposterior and oblique pouch X-rays showed no passage up to an average volume of 520 ml (270-650) though the descending colon. The sigmoidal colon pressure that was on average 20 cm H(2)O at the preoperative evaluation was measured as 6 cm H(2)O at the 3rd month and 6.5 cm H(2)O at the 6th months during the postoperative period. 24 hour natural pouch pressure was found to be 8.7 cm H(2)O on average while the pressure was found to be 13.8 cm H(2)O on average when the patient felt abdominal discomfort, in other words the desire to defecat (miction).

A modified sigmoidorectal pouch procedure not only provides a reservoir with a higher capacity and lower pressure without a reflux to the upper urinary tract and descending colon with lower metabolic acidosis problem, but it is also a good alternative diversion procedure that whould be preferable especially in Muslim countries as it does not cause any difficulties in terms of Islamic worship.