OUTCOME OF EXTRACORPOREAL SHOCKWAVE LITHOTRIPSY MONOTHERAPY FOR LARGERENAL CALCULI - EFFECT OF STONE AND COLLECTING SYSTEM SURFACE-AREAS AND COST-EFFECTIVENESS OF TREATMENT

The treatment options for large renal calculi are controversial. We re port on our experience with 65 treatments of renal calculi >3 cm using extracorporeal shockwave lithotripsy (SWL) monotherapy. We stratified our results according to stone and collecting system surface areas (m easured by computer image analyses), stone location, and stone type. T he overall success rate of SWL monotherapy was 27% at 3 months. The be st stone-free rate (60%) was obtained for stones <500 mm(2) and locate d primarily within the renal pelvis. The stone-free rate for stones wi th surface areas >1000 mm(2) was only 8%. None of the cystine stones w as treated successfully, whereas 80% of patients with uric acid stones became stone free. We estimated an average cost of $67,048 to render a patient with a large renal calculus stone free using SWL monotherapy . We recommend that other treatment options, such as percutaneous neph rolithotomy, be considered as first-line therapy for large renal calcu li.