Fulguration of posterior urethral valves using the Nd:YAG laser.

Abstract

Endoscopic management is the accepted form of treatment for posterior urethral valves (PUV). The Nd:YAG laser has been in clinical use for many decades, but has been used only sporadically for ablating PUV. In this study, PUV were diagnosed by micturating cystourethrogram (MCU). In the 9-month period beginning March 1997, 23 boys 3 months to 9 years of age underwent endoscopic Nd:YAG laser surgery for PUV using a 600 quartz bare fibre through the catheter channel of an 8.5 F cystoscope. The laser power and total energy delivered ranged from 20 to 50 W and 50-1085 J, respectively. Type I PUV were present in 20 boys; 1 had type III, and in 1 boy each there were residual valves and a urethral stricture from a previous electrocautery ablation. All operations were done with the patient under general anaesthesia supplemented by caudal morphine. Routine postoperative cystoscopy was done in the first 5 cases only. All patients had a good stream of urine without bleeding or any other complication after valve ablation. Mucosal tags seen on follow-up cystoscopy in 5 patients were fulgurated by laser. In 4 other patients recystoscopy was required for deterioration of the urinary stream and persistent posterior urethral dilatation on MCU; residual valves were refulgurated by laser. An indwelling catheter was left in only 4 patients, 2 of whom were primarily operated and 2 following refulguration. All except the first 2 were treated as out-patients. Application of the Nd:YAG laser has added a new dimension for treating PUV. The initial experience has been very encouraging: the destruction of valves is precise, there are no complications, and it can be practised on a day-care basis without indwelling catheterisation. The bare fibre can be used repeatedly, thus reducing the cost of treatment.