Extracorporeal shock wave lithotripsy for staghorn calculi

Abstract

Forty eight patients with large renal staghorn calculi of more than 35mm in maximum length on plain X ray were treated by extracorporeal shock wave lithotripsy (ESWL) monotherapy during a period of 2 years. Thirty of these patients, with a follow up of more than 6 months after the last treatment, were included in this study. The surface area of the calculi was 12.9 cm2 on average. According to plain X rays, 9 patients (30%) became free of calculi while 12 patients (40%) retained a small amount of tiny residual fragments (less than 1 cm2 in area). Adding these cases to those in which all the residual calculi had been eliminated produces a total of 21 cases (70%) leading us to correlate that ESWL was effective for the treatment of staghorn calculi. The remaining 9 cases (30%) retained a considerable amount of larger residual fragments (more than 1 cm2 in area). The present study on ESWL for large staghorn calculi revealed no clear relationship between the surface area of the stones and evacuation of the fragments. The amount of residual fragments was significantly small when either the renal collecting system was less than 20 cm2 in area (p<0.05), or when the ureteropelvic junction (UPJ) was equal to or greater than 5 mm in diameter (p<0.02), according to intravenous pyelography performed prior to treatment. The complications associated with this treatment were minimal, with a high fever in only 3 cases, and these complications could be treated easily by antibiotic therapy. ESWL monotherapy thus appears to be effective for the treatment of staghorn calculi, causing a few complications. We conclude that, cases showing a collecting system of less than 20 cm2 in area and cases showing a UPJ diameter equal to or greater than 5 mm on IVP prior to treatment, are probably all good candidates for ESWL monotherapy.