Computed Tomographic Appearance of Orthotopic Neobladder: Correlation with Voiding Pattern

Lee, Ji Youl; Kim, Sae Woong; Park, Wang Jin; Chung, Kee Uk; Lee, Seung Ju; Jung, Seung Eun; Cho, Yong Hyun; Yoon, Moon Soo

Abstract

PURPOSE: To define computed tomographic (CT) appearance according to voiding patterns and to evaluate the significance of CT in patients with voiding dysfunction after orthotopic bladder substitution following radical cystectomy.
MATERIALS AND METHODS
We evaluated a total of 50 male patients in whom 25 had undergone an ileocolic and 25 had undergone an ileal neobladder. We performed uroflowmetry, postoperative voiding cystourethrography (VCUG) and CT for evaluation of configuration of neobladder according to voiding pattern. We defined a good voider (n=37) as the patients with maximum flow rate greater than 15 ml/sec and postvoid residual urine amount less than 200ml and a poor voider (n=13) as those with less than 15 ml/sec or greater than 200ml.
RESULTS
Voiding cystourethrography revealed that the neobladder outlet was well funneled and wide open at the most dependent portion of the neobladder in good voider group. However, in poor voider group, the neobladder outlet was not funneled or deviated from its caudal location. CT revealed that the neobladder was symmetric in 28 cases (75.7%) and had soft tissue density in the neobladder base in 9 cases (24.3%) of good voider group. However, neobladder was asymmetric in 8 cases (61.5%) and had soft tissue density in the neobladder base in 8 cases (61.5%) of poor voider group.
CONCLUSIONS
The asymmetry of neobladder and soft tissue density around base of neobladder on CT may be associated with the deviated neobladder outlet. This CT finding might be useful to presume the cause of voiding pattern.