Experimental Study On The Effectiveness Of An Anti-reflux Ureteral Stent

Objective To investigate the drainage potency and anti-reflux properties of a new anti-reflux ureteral stent in animal models,with the aim to increase feasibility of clinical application.Methods Bilateral ureters of 6 pigs were randomly divided into group A and group B.Ordinary ureteral stents were placed in ureters of animals in group A,whereas novel anti-reflux ureteral stents were placed in ureters of animals in group B.Prior to this point,ureters without a stent placement were placed into group C.Drainage potency and anti-reflux properties of the animals in the three groups were examined,and the data was compared and analyzed.Results For the detection of drainage potency and anti-reflux property animals underwent surgery,and saline was injected into the pelvis fistula under pressure of30 cm H2 O and 50 cm H2 O.The difference in drainage potency of stents in animals in group A and group B was not statistically significant(P>0.05),however it was superior to that of animals in group C(P<0.05).No stent that was placed in animals in group A showed anti-reflux properties at the time of urination(0%,0/6),whereas all stents placed in animals in group B displayed anti-reflux property(100%,6/6).The average ureteropelvic pressures in groups A,B,and C were 16.67±1.63 mm Hg,8.17±0.75 mm Hg,and 7.08±0.90 mm Hg,respectively,and differences between groups were statistically significant(P<0.05).Conclusion We found that the anti-reflux ureteral stent displays better anti-reflux properties compared to a traditional ureteral stent.In addition,the drainage potency between anti-reflux ureteral stents and ordinary ureteral stents was similar.However,the anti-reflux stent has certain limitations,which should be improved through clinical studies.To reduce post-placement complications in patients,all product properties should be perfected before application in the clinic.The anti-reflux device of the ureteral stent is designed to target internal reflux.We believe that the vesicoureteral reflux that occurs after stent placement is mainly caused by internal reflux.