Sigma-rectum pouch (Mainz Pouch II) operation, which is a detubularized modification of the well-known ureterosigmoidostomy is becoming a popular alternative of urinary diversion in selected patients. 12 male patients underwent this operation due to locally invasive bladder tumours or incurable urethral strictures and fistulas. The pouch was tailored using 12 cm of sigmoid colon and rectum and performing a side to side anastomosis of the detubularized bowel in an inverted U shape. The new formed pouch was fixed onto the posterior peritoneum so that traction affecting the pouch was minimized. Postoperative radiological analysis revealed no obstruction or ureteral reflux. Urodynamic studies revealed low pressure, high volume reservoirs. Only 1 patient had reservoir wall contractions of low amplitude during filling. Although early postoperative blood chemistry did not reveal any metabolic abnormality, at long-term follow-up some patients showed important electrolyte and acid-base disorders.
