MORPHOLOGICAL CHANGE IN THE UROTHELIUM AFTER ELECTROHYDRAULIC VERSUS PULSED DYE-LASER LITHOTRIPSY

Objective To observe morphological changes in the urothelium after exp osure to laser beam and electrohydraulic spark. Materials and methods The pulse dye laser lithotripter (MDL-2, Candela Corporation, Boston, USA) and the electrohydraulic lithotripter (AEH-2, Circon ACMI Corpora tion Stamford, USA) were used directly on the bladder mucosa in six pi gs. Immediately after treatment, the bladder mucosa was prepared for l ight microscopic and scanning electron microscopic examination. Result s Both electrohydraulic spark and laser beam caused mucosal denudation , submucosal swelling and haemorrhage, There was a positive correlatio n between the degree of urothelial damage and the power and pulse numb ers applied. Conclusion Direct contact of the urothelium in patients t reated with laser beam or electrohydraulic spark should be avoided.