LASERLITHOTRIPSY USING A PULSED DYE-LASER WITH AUTOMATIC SHUNT-OFF AFTER TISSUE CONTACT - A NEW ASPECT FOR DIFFERENTIAL THERAPY OF URETERALSTONES

The development of laser induced shockwave lithotripsy via small glass fibres introduced a new generation of miniaturized ureteroscopes lead ing to a further use of ureteroscopy. Between June 1991 and December 1 992 124 patients with 33 upper, 52 middle and 48 distal ureteral calcu li were treated at the Department of Urology at the Katharinenhospital in Stuttgart using a flashlight pumped tunable dye laser. The dye use d was Rhodamine, emitting light of a wave length of 594 nm with an ene rgy at the distal tip of the fibre between 30 and 150 mJ. The fibres' diameter were 250 and 300 mum. By spectral analysis of the reflected l ight, immediate shut off of the laser is performed after tissue contac t. Laser-lithotripsy was only indicated when in situ ESWL had been uns uccessful or impossible, and retrograde mobilisation or extraction fai led. On the average, 1589 impulses at a mean energy of 86.8 mJ were ap plied. In 75 cases (60.5 %) complete disintegration was achieved. In 4 7 patients (38.0 %) partial disintegration was noted leading to retrog rade mobilisation of fragments followed by ESWL in 39 patients. Ureter oscopic extraction of fragments was performed in 8 cases. In two patie nts lasertripsy failed, one stone could be extracted secondarily, one patient was treated with ureterolithotomy. All patients were rendered stone free after six weeks. Due to ureteroscopic manipulation mucosal lesions were found in 7 patients (5.4 %). No laser dependent trauma wa s seen. In 88 patients (70.9 %) a double J stent was inserted after th e procedure. In conclusion, laserlithotripsy using a pulsed dye laser with automatic stone recognition represents a safe and effective appro ach for ureteral calculi and will play an increasing role in modern ur ology in the near future.