Experience with a New Multifunctional Lithotripter, the Dornier MFL 5000: Results of 415 Treatments

Abstract

The Dornier MFL 5000 is a new multifunctional work station for urologic diagnosis, endourology, and extracorporeal shock wave lithotripsy (ESWL). Features of this bathfree device include a tiltable U-arm with an under-table x-ray tube for stone localization, a low-pressure generator with twin-pulse technique, a modified semiellipsoid reflector, and an ultrasound unit for stone localization and monitoring. From April 1988 until January 31, 1989, 415 ESWL treatments were performed on this machine. The stones were 45.6% (189) caliceal, 25% (108) renal pelvic, 26% (108) ureteral, and 2.4% (10) branched. The majority of stones had a diameter between 8 and 20 mm. Stone disintegration required a mean of 2450 impulses. Mean treatment time was 33 minutes. Mean final generator voltage was 20 kV (range 17 to 24 kV). Post-ESWL ancillary procedures proved to be necessary in 24 patients (5.8%). The retreatment rate was 19.5% (81) including 4.8% (20) with planned multiple treatments. In 86.6% (359) of patients, a noninvasive oral analgesia technique was used successfully. Follow-up at 3 months could be obtained in 59.5% (247). The overall stone-free rate was 77.5% (191). ESWL was unsuccessful in 2.4% (10). The results of this study are comparable to those achieved with the modified Dornier HM3. The MFL 5000 has advantages, especially in the treatment of lumbar ureteral stones in situ, less radiopaque stones, and in obese patients. The under-table x-ray tube considerably reduces radiation exposure to room personnel and the treating urologist. Excellent imaging qualities are provided by the 14-inch image intensifier. The MFL 5000 proved to be satisfactory for a variety of endourologic procedures.