To evaluate whether the polymer microsphere diameter affects the success rate in the endoscopic treatment of vesicoureteral reflux.

In our consecutive series, 56 patients underwent subureteral injection with Dexell and 60 patients were treated with Deflux. Patients were evaluated with pediatric lower urinary tract scoring system, uroflowmetry, and a residual urine volume and voiding diary at the time of injection and control. Patients with grade V reflux, duplex systems, paraureteral diverticula, or refractory lower urinary tract symptoms were excluded. The numbers of renal units with grade II-III vesicoureteral reflux were 78 and 73 in the first (Deflux) and second (Dexell) groups, respectively. The numbers of renal units with grade IV reflux were 24 and 17 in the first and second groups, respectively. The resolution rate was determined by voiding cystourethrogram at the third postoperative month. Postoperative febrile urinary tract infections and de novo scars in dimercaptosuccinic acid were noted. Groups were compared by the χ² test.

Mean follow-up time and mean age of the children were not significantly different. The number of nondilating and dilating renal units was not significantly different. Resolution rates were similar between the groups (79.5 and 78%, respectively). There was no significant difference in terms of resolution rates when dilating and nondilating urinary systems were separately analyzed. The average volumes used per renal unit were 0.9 and 1.6 mL in the first and second groups, respectively (P < .005). Postoperative febrile urinary tract infection and de novo scar formation rates were similar.

The diameter of dextranomer microsphere does not affect the short-term success rate in endoscopic treatment of vesicoureteral reflux. Multicentric, randomized and prospective studies are required for long-term clinical results.