Appendicovesicostomy (and variations) in bladder reconstruction.

Bladder reconstruction using bowel segments was advanced when intermittent catheterization proved so acceptable. Access to the reservoir by way of the urethra is often not possible in children, especially boys. Implantation of the isolated appendix into the bladder remnant or colon segment similar to a ureteral reimplant provides a continence mechanism with ready catheter access (the Mitrofanoff principle). Since 1982 we have applied this principle in 41 pediatric cases of bladder reconstruction (64% boys). Primary diagnoses included bladder exstrophy (46%) and myelomeningocele (34%). Extending the concept of a flap valve continence channel with a narrow tube into the reservoir, segments of tapered ileum and ureters were also used (appendix 61%, ileum 12%, ureter 27%). Results of continence (100%) and uncomplicated catheterization (93%) have been satisfactory. Unfortunately, the longer the experience (average 3.2 years of followup), the more stone formation we experienced (32%), which is due to mucus production and bacteriuria as the stone nidus. There were 2 deaths, including 1 from a renal stone obstructing the ureter with sepsis and 1 a likely suicide. Reoperation was required for 3 stomal revisions, 2 bowel obstructions and 7 stone removals in 3 of the 6 cases in which the bladder neck was closed. Unique aspects of these reconstructions are presented, such as our current preference to bury the stoma in the umbilicus (7 cases), placement of the ureteral segment into the perineum as a neourethra and an unusual conjoined twin reconstruction.