URODYNAMIC INVESTIGATIONS IN REVERSED ILEAL SEROMUSCULAR ENTEROCYSTOPLASTY - AN EXPERIMENTAL-STUDY IN A RABBIT MODEL

Objective To investigate the efficacy of the reversed ileal seromuscul ar enterocystoplasty (RISMEC) technique and assess the urodynamic find ings. Materials and method A large bladder defect was created in 12 Ne w Zealand White rabbits; in six the bladder was closed primarily (cont rol group) and in the remaining six the bladder was augmented using th e RISMEC technique combined with omentoplasty. The results were assess ed using intravenous pyelography (IVP), voiding cysto-urethrography (V CUG), histopathological investigations and urodynamic studies after 4 and 12 weeks. Results The IVP and VCUG revealed an apparently normal u rinary system and voiding pattern in both groups. Histopathologically, in all rabbits undergoing RISMEC, the serosal surface of the reversed ileum was lined with transitional urinary epithelium; there was no ev idence of severe fibrosis, inflammation, stone or mucus production, Ur odynamic studies showed a significant decrease in the mean bladder cap acity in the controls, but no significant change in the RISMEC group. The mean bladder compliance decreased from 5.85 to 1.36 mL/cmH(2)O in the controls (P<0.02) but there was no significant decrease in complia nce in the RISMEC group. Conclusion The results suggest that in this r abbit model, the RISMEC technique combined with omentoplasty increases bladder capacity with minimal graft shrinkage; the peritoneal surface is rapidly covered with transitional epithelium and the integrity of the kidneys preserved, Urodynamic investigations showed neobladders wi th adequate storage capacity, low intravesical pressures and improved compliance rates.