Voiding Patterns of the Orthotopic Neobladder: Clinical, Urodynamic and Radiographic Analysis

Lee, Ji Youl; Lee, Seung Ju; Cho, Young Lae; Kim, Sae Woong; Cho, Yong Hyun; Yoon, Moon Soo

Abstract

PURPOSE: We evaluated voiding patterns and voiding dysfunction after orthotopic bladder substitution in patients with bladder cancer.
MATERIALS AND METHODS
We examined a total of 40 male patients of whom 25 had undergone an ileocolic and 15 had undergone an ileal neobladder. We interviewed the patients and obtained 3-day voiding diary in all patients and performed urodynamic study and voiding cystourethrography.
RESULTS
When a good voider is defined as the patient with maximum flow rate of 15ml/sec or more and a poor voider is less than 15ml/sec, mean maximum flow rate in good voiders was 20.4+/-4.2ml/sec compared with 8.2+/-3.1ml/sec in poor voiders. Maximum bladder capacity, vesical opening pressure, and vesical pressure at the maximum flow rate were not different significantly between the two groups. All patients voided by abdominal straining and relaxing the pelvic floor musculature in pressure-flow study. However, voiding patterns revealed differences between good and poor voiders. In good voiders, a single long-lasting abdominal straining achieved a smooth voiding, while in poor voiders, short-lasting frequent abdominal strainings resulted in interrupted and obstructive urine flow. Good continence during day and night was achieved in 90.6% and 81.3% of the good voiders and 87.5% and 87.5% of the poor voiders. The maximum urethral closure pressure and the functional urethral length decreased in incontinent patients. Voiding cystourethrography revealed that the reservoir was symmetric and its outlet was well funnelled and wide open at the most dependent portion of the reservoir in good voiders. However, in poor voiders, the reservoir revealed asymmetric configuration and its outlet did not funnel or deviated from its caudal location.
CONCLUSIONS
Neobladder patients void by abdominal straining in coordination with the relaxation of pelvic floor musculature. Correct location of the neobladder outlet, minimum injury to the urethral anastomosis, and maximum preservation of the proximal urethra are required to the neobladder patients to obtain good voiding and continence.