[Mainz pouch using the appendix as the efferent limb].
Mainz pouch procedure requires intussuscepted ileum only at the efferent limb because ureters are tunneled into the colon wall in stead of the intussuscepted ileum as done in the Kock pouch procedure. We modified the Mainz pouch procedure using the tunneled appendix as the efferent limb in which intussuscepted ileum was no longer required. Four patients, three with bladder cancer and one with prostatic cancer, underwent this procedure. After total cystectomy and pelvic lymph-adenectomy the pedicled ileocecal segment was isolated. The appendix with the intact vascular supply was separated from the ileocecal segment. After the pouch was constructed, both the ureters and the appendix were tunneled into it. The pouch was then drained by a 24 Fr nephrostomy catheter. The ureters were splinted. The pouch was closed in one layer with locked running sutures. Three patients had ureteral strictures, 2 of which were corrected by percutaneous dilatation. The third one required persistent nephrostomy drainage. The appendix of all 4 cases functioned well as the efferent limb, preventing urinary leakage and allowing easy catheterization. Three of the 4 patients satisfied with this type of urinary diversion. The modified Mainz pouch procedure may be very useful because it does not require any staples to fix the intussuscepted ileum nor a long intestinal segment. Patients whose appendix can not be utilized may be candidates for the original Mainz pouch procedure.