Do Volume of Injection and Learning Curve Influence the Results of Endoscopic Correction of Vesicoureteric Reflux Using Dextranomer/Hyaluronic Acid? A Single Surgeon Experience.

Background: Available reports regarding the technical factors for successful endoscopic treatment (ET) of vesicoureteric reflux (VUR) using dextranomer/hyaluronic acid copolymer are inconclusive. We studied single-surgeon data to evaluate the association of injected volume and surgeon experience with success after ET for VUR. Materials and Methods: Fifty-eight children (87 ureters) with grades 2-4 primary VUR were included. Success was defined as complete resolution of reflux on follow-up imaging. Volume of injection between success and failed groups was analyzed; volume of injection was further studied using receiver operating characteristic curve (ROC) analysis. Patients were then divided into two groups: group 1 (early experience) and group 2 (later experience). Both groups were compared for age, grade of reflux, volume of injection, and success. Results: Overall success of one injection was 76%. The mean volume of injection was significantly larger in successful ureters than failed ureters ( P  = .008). On ROC analysis, the volume of 0.75 mL (area under curve 0.747, 95% confidence interval 0.60-0.89) had a good discriminative ability to predict success of the injection procedure. Furthermore, a volume cutoff of 0.8 mL demonstrated significant influence on success (success 14/25 ureters for <0.8 mL and 36/42 ureters for 0.8 mL or more volume of injection, P  = .0097), whereas no difference in success was observed with a cutoff volume of 0.9 mL ( P  = .2480). When the patients were divided into two groups based on surgeon experience, group 2 demonstrated better success than group 1 (84% versus 65%, P  = .04). Both groups were comparable for age ( P  = .09), grade of reflux (0.46) and the median volume of injection was similar (0.8 mL) in both the groups. Conclusions: We found that a minimal volume of 0.75 mL dextranomer/hyaluronic acid injection may be required to achieve success of ET in moderate grade primary VUR. Success also improved with increasing surgeon experience.