Can distal ureteral diameter predict reflux resolution after endoscopic injection?

OBJECTIVE: To test the predictive value of distal ureteral diameter (UD) on reflux resolution after endoscopic injection in children with primary vesicoureteral reflux (VUR).

MATERIALS AND METHODS: This was a retrospective review of patients diagnosed with primary VUR between 2009 and 2012 who were managed by endoscopic injection. Seventy preoperative and postoperative voiding cystourethrograms were reviewed. The largest UD within the false pelvis was measured. The UD was divided by the L1-L3 vertebral body distance to get the UD ratio (UDR). One radiologist interpreted the findings of voiding cystourethrography in all patients. Clinical outcome was defined as reflux resolution.

RESULTS: Seventy patients were enrolled in this series (17 boys and 53 girls). Mean age was 5.9 years (1.2-13 years). Grade III presented in 37 patients (53%), and 33 patients (47%) were of grade IV. Mean distal UD was 5.5 mm (2.5-13 mm). Mean UDR was 37.8% (18%-70%). Macroplastique injection was performed in all. Subureteric injection was performed in 60 patients (86%), whereas intraureteric injection was performed in 10 patients. No postoperative complications were detected. The effect of grade, UD, and UDR on success after endoscopic injection was tested. UD and UDR were significant predictors of reflux resolution on logistic regression analysis (P <.007 and .001, respectively).

CONCLUSION: UDR provides an objective measurement of VUR and appears as a predictive tool of success after endoscopic injection.