LASERTRIPSY OF URETERAL CALCULI USING PULSED-DYE LASER WITH AUTOMATIC SHUTOFF AFTER TISSUE CONTACT

Since June 1991, 54 patients with ureteral calculi (13 upper, 18 middle, and 23 distal) have been treated in our department using a flashlamp-pumped tunable-dye (rhodamine 6G) laser with a wavelength of 594 nm with an energy at the distal fiber tip between 30 and 120 mJ. The fiber core diameters were 200 and 300 mum. By spectral analysis of the reflected light, immediate shut-off of the laser was obtained after tissue contact. In average, 1599 impulses at a mean energy of 76.4 mJ were applied. In 32 cases (59%), complete disintegration was achieved. In 22 cases (41%), partial disintegration was noted, leading to retrograde mobilization, of the fragments followed by SWL in 16 patients. Ureteroscopic extraction of fragments was performed in six patients. All patients were rendered stone free after 6 weeks. Because of the ureteroscopic manipulation, mucosal lesions were found in five patients, but no trauma attributable to the action of the laser was seen. In 42 patients, a double-J stent was placed after the procedure. Lasertripsy using a pulsed-dye laser with automatic shut-off after tissue contact is a safe and effective approach that offers a new aspect in the noninvasive treatment of recalcitrant ureteral calculi in our department.