THE CASE FOR PRIMARY ENDOSCOPIC MANAGEMENT OF UPPER URINARY-TRACT CALCULI .1. A CRITICAL-REVIEW OF 121 EXTRACORPOREAL SHOCK-WAVE LITHOTRIPSY FAILURES

Objectives To define those patients with upper urinary tract calculi w ho are more likely to have an unsuccessful outcome from extracorporeal shock-wave lithotripsy (ESWL). Methods. A critical prospective analys is of 121 patients, referred to two university centers after ESWL had been exhausted as a treatment modality for upper urinary tract calculi , was performed. Patients were subdivided into the following groups: f ailure to clear fragments, failure to fragment, difficulty in calculus localization, and failure due to inherent upper urinary tract obstruc tion. Other important variables include the type of extracorporeal lit hotriptor used, number of treatment sittings before referral, calculus location, calculus composition, patient body habitus, and the imaging leading to and associated with extracorporeal therapy. Results. Large renal calculi (mean, 22.2 mm) and those within dependent or obstructe d portions of the collecting system were frequently referred for endos copic management after failed ESWL. Steinstrasse can be an extremely m orbid complication from ESWL and in this series was associated with ir reversible loss of venal function and ureteral stricture disease. Extr acorporeal lithotripsy of infectious calculi can be associated with se vere septic complication. inadequate preoperative and intraoperative i maging and morbid obesity were also associated with failure. Second- a nd third-generation lithotriptors were represented in greater numbers than the Dornier HM-3 in this group of ESWL failures. Conclusions. ESW L remains the treatment of choice for moderately sized, uncomplicated renal calculi. Large calculi, those within obstructed or dependent por tions of the collecting system, and those composed of calcium oxalate monohydrate, frequently fail ESWL. Training in the more technically ch allenging aspects of endoscopic lithotripsy must be encouraged.