Urodynamic characteristics of the modified orthotopic ileal neobladder.

Background/aim: Radical cystectomy is the method of choice in management of muscle invasive, organ-confined tumors of the bladder (T2-T4, N0-Nx). The most frequent continent orthotopic urinary diversion after radical cystectomy is the ileal neobladder. A modified technique consists of using a shorter segment of the terminal ileum than the standard technique, around 30 cm. The aim of this study was to determine the urodynamic characteristics of the orthotopic ileal neobladder created by a modified technique.

Methods: In this prospective clinical study we analyzed the urodynamic parameters of 24 patients who had underwent radical cystectomy with orthotopic urinary diversion by ileal neobladder created using a modified technique. In all the patients we performed invasive and noninvasive urodynamic investigations 12 months after the operation. The urethral pressure profile parameters analyzed were maximal urethral pressure, maximal urethral closure pressure and the functional urethral profile length.

Results: The average age of the patients was 63 (49-73) years, 90% were males and 10% were females. The median length of the shorter segment of the terminal ileum was 28 (range 22-35) cm. Prior to enterocystometry and uroflowmetry postvoid residual (PVR) urine was measured by a urethral catheter. The median PVR was 16.7 (0-140) mL. The median enterocystometric capacity was 396 (range 372-532) mL. The median end filling pouch pressure was 27.6 (range 20-70) cmH2O. The median maximal flow of urine was 22.1 (range 9.7-39.5) mL/s and the average flow of urine was 9.61 (range 3.6-17.6) mL/s. Flow time in the analyzed group was 47.5 (range 22-119) s. The median maximal urethral pressure was 54 (range 12-101) cmH2O, maximal urethral closure pressure 36.6 (range 6-91) cmH2O. Functional urethral profile length was 14.9 (range 4-37) mm.

Conclusion: An ileal orthotopic pouch created by a modified technique using a shorter segment of the terminal ileum after 12 months presents with urodynamic characteristics similar to the native bladder.