The effect of the ureterovesical junction on urinary peristaltic flow

摘要

Vesicoureteral reflux (VUR), or the reversed flow of urine from the bladder into the ureter, is an anatomic and functional disease that can result in serious misery, both from intense infection and from sequelae of reflux nephropathy. Therefore a valve mechanism is created to defend the flow from retrograding. The objective of this study was to inspect the response of the ureteric flow to the closure of ureterovesical junction (UVJ) with the aim of explicating the valve mechanism of UVJ anti reflux. In this study the navier-stokes equations were used for the fluid domain. Also the peristaltic motion was constructed using a moving obstruction on the wall which was assumed to be rigid. This model was solved by varying the minimum lumen cross-section (orifice opening) area, the pressure difference between the bladder and the renal pelvis, and the average velocity of the peristaltic wave. The results corresponding to the anti-relflux ureteral valve mechanism exhibited that its existence was essential, and therefore the pelvis was secured of the reflux. Also the results demonstrated that the ureteropelvic reflux decreased as the bolus became larger.