Early outcome following diathermy versus cold knife ablation of posterior urethral valves

ObjectiveTo compare early outcomes following diathermy versus cold knife ablation of posterior urethral valves (PUV).MethodsAll neonates and children who underwent primary ablation of PUV between January 2004 and March 2011 were included. Primary ablation was performed using an 8.5 resectoscope, with either diathermy hook (Group I) or sickle-shaped cold knife (Group II). A uniform management protocol was used and voiding cystourethrogram was repeated in all patients at 3 months follow-up. All patients with poor anterior urethral stream and persistent dilatation of posterior urethra on follow-up underwent repeat cystoscopy. Early outcomes were compared between Groups I and II using Fisher's exact test.ResultsDuring the study period, a total of 83 cases underwent primary PUV ablation. Group I included 42 patients (mean age 6.2 months; 10 days to 9 years) while Group II included 41 (mean age 3.4 months; 12 days to 5 years). Overall 12/83 (14.4%) required repeat procedure for persistent obstruction: stricture 9 (10.8%); residual valve 3 (3.6%). Group I had a significantly higher stricture rate (9/42; 21.4%) than Group II (0/41) (p = 0.02). There was no significant difference in terms of residual valves, haematuria, retention or extravasation between groups.ConclusionCold knife ablation is superior to diathermy in relieving PUV obstruction in a single attempt.