Objective   To investigate the urodynamic features and the relative high risk factors of upper urinary tract deterioration for W-shape orthotopic ileal neobladder.    Methods   One hundred and five patients (90 men and 15 women; mean age

54±10) which had follow-up data of W-shape orthotopic ileal neobladder (mean time 20±6 months

ileal neobladder group)

and 20 patients (15 men and 5 women; mean age

56±10

control group) with upper urinary tract diseases who had normal lower urinary tract function were included in this retrospective study. All patients were evaluated by urodynamic examinations

cystourethrography

B-ultrasound

renal function test and voiding feature. The related parameters from both groups were analyzed comparatively. Meanwhile patients who were evaluated by cystourethrography in orthotopic ileal neobladder group were divided into 2 groups

reflux group and non-reflux group according to they having vesicoureteral reflux or not. The related parameters from both groups were analyzed comparatively.    Results   Urine flow curve was interrupted or plateau shape in ileal neobladder group

but it was bell shape in control group. Maximum flow rate was 12±4 ml/s

significantly lower than it in control group (21±5 ml/s). However

postvoid residual urine volume (PVR) and maximum cystometric capacity (MCC) were 47±22 and 533±166 ml respectively in orthotopic ileal neobladder group

significantly higher than those in control group (8±7 and 412±57 ml

P0.05). In contrast to the normal bladder

ileal neobladder had markedly decreased sensation

good stability

and not significantly desire to void. There were merely 9 patients having observed peristaltic wave

which having lower amplitudes in a certain rule and the frequency was gradually increased then reduced with augmented priming volume. In 3 months’ postoperative followed-up

there were 90 patients having no vesicoureteral reflux observed by cystourethrography

but 11 patients had vesicoureteral reflux with extension of follow-up. Compared with non-reflux group

PVR

MCC

maximum voiding pressure(MVP) and the rate of lower opening function for bladder neck were found significantly higher in reflex group.    Conclusion   W-shape orthotopic ileal neobladder has special urodynamic features

which are different from normal bladder. Increased PVR

MCC and MVP and lower opening function for bladder neck are the high risk factors of upper urinary tract deterioration.