The reliability of VCUG performed within 24 hours after injection of dextranomer/hyaluronic acid in patients with vesico-ureteral reflux

Objective To assess the reliability and negative predictive value of voiding cystourethrogram (VCUG) performed within 24 hours postoperatively. Methods Forty patients (56 ureters) who underwent first injection of dextranomer/hyaluronic acid (Dx/HA) because of vesicoureteral reflux (VUR) were enrolled. Patients with previous reflux operation or neurogenic disorders were excluded. All patients underwent the hydrodistention implantation technique (HIT). Patients underwent VCUG within 24 hours postoperatively and after 6 months. Grade 0 and grade 1 were considered to be cured. Negative predictive values of VCUG performed within 24 hours postoperatively were assessed. Results The mean age of the patient was 98 ± 45.8 months. Twenty-seven patients were male and 13 patients were female. The number of refluxing ureters was 4, 12, 14, 12, and 14 in ascending order of VUR grade. Overall success rate of single injection therapy was 66.07%. Only 2 ureters with grade IV and 1 patient with grade V VUR showed failure on 24-hour VCUG. The success rates on 6 months VCUG were 100%, 83.3%, 78.57%, 50%, and 42.85% according to ascending order of VUR grade.The negative predictive value of 24-hour VCUG were 100%, 83.3%, 78.57%, 60.0%, and 46.15% according to ascending order of VUR grade. VUR grade was the only factor associated with the discrepancy. Positive but weak correlation was noted between the preoperative grade of VUR and the rate of discrepancy on Spearman correlation analysis (Spearman correlation coefficient = 0.303, P value =.018). Conclusion Twenty-four hour VCUG cannot replace follow-up VCUG usually performed beyond 3 months postoperatively. Further studies are needed for confirmation of cure.