Prospective study using a new bulking agent for the treatment of vesicoureteral reflux: polyacrylamide hydrogel.

Abstract

Vesicoureteral reflux is frequently diagnosed in the pediatric population. Endoscopic treatment has become a popular form of first-line therapy. Available products offer good short-term success rates. However, the cost of these injected implants is an issue. We evaluated the success of endoscopic treatment for vesicoureteral reflux using polyacrylamide hydrogel. We performed a single center, single surgeon, prospective, off-label study using polyacrylamide hydrogel to treat vesicoureteral reflux. All patients underwent endoscopic subureteral double hydrodistention implantation technique injection followed by renal ultrasound and voiding cystourethrogram at 3 months postoperatively to confirm the absence of de novo hydronephrosis and correction of vesicoureteral reflux (grade 0). A total of 40 patients (69 refluxing ureters) underwent polyacrylamide hydrogel injection. Median age at surgery was 50 months. Bilateral reflux was identified in 29 patients (73%). Nine patients had duplex systems, 2 with reflux into both moieties. Reflux was graded using the International Reflux Study in Children grading system, with grade I seen in 9 ureters, II in 17, III in 20, IV in 18 and V in 5. Mean volume injected was 1.1 ml. Success rate for grade I to III vesicoureteral reflux at 3 months after a single treatment was 87%, and the overall success for all grades was 81.2%. Off-label use of polyacrylamide hydrogel injection therapy for primarily low grade vesicoureteral reflux demonstrates that the technique and short-term success rates are comparable to the most popular bulking agent, dextranomer/hyaluronic acid. These results suggest that further trials comparing polyacrylamide hydrogel and dextranomer/hyaluronic acid would be worthwhile.