Dynamics of neurogenic bladder with vesicoureteral reflux

Objective To explore the dynamic differences of neurogenic bladder (NB) with ureteral reflux with or without detrusor overactivity so as to provide therapetic rationales. Methods A total of 68 children were diagnosed as NB vesicoureteral reflux by videourodynamics from 2003 to 2005. There were 30 boys and 38 girls with a mean age of 7.5 (4-12) years. Based upon the presence or absence of detrusor overactivity (DO), they were divided into DO group (n=20) and non-DO group (n=48). During vesicoureteral reflux, bladder capacity and detrusor pressure were recorded and bladder compliance was calculated. And the maximal levels of cystometry capacity and detrusor pressure were recorded and bladder compliance was calculated at the end of filling in two groups. According to the level of reflux flow, they were divided into mild reflux (Ⅰ-Ⅱdegrees), severe reflux (Ⅲ-Ⅴdegrees). Reflux side and severity were compared for two groups. Results During vesicoureteral reflux, bladder capacity and compliance were 98.7±16.1 ml and 5.2±1.9 ml/cmH2O in DO group versus 127.3±36.3 ml and 7.1±2.1 ml/cmH2O in non-DO group. The differences had statistical significance. The detrusor pressures of two groups were 21.6±9.2 and 19.2±7.4 cmH2O respectively. There was no significant statistical difference. At the end of filling, bladder capacity and compliance were 182.7±31.2 ml and 5.4±1.7 ml/cmH2O in DO group versus 230.6±34.6 ml and 6.5±1.1 ml/cmH2O in non-DO group. The differences had statistical significance. In DO group, reflux was unilateral (n=12, 60%) and bilateral (n=8, 40%); in non-DO group, unilateral (n=16, 33%) and bilateral (n=32, 67%). All refluxes of two groups were severe. Conclusions Small bladder capacity and poor bladder compliance are two major dynamic characteristic of NB children with ureteral reflux during DO. Key words: Bladder, neurogenic; Vesico-ureteral reflux; Urodynamics