Extracorporeal Shock Wave Lithotripsy Experience with Large Renal Calculi*

Abstract

Among the first 1000 cases in a single extracorporeal Shockwave lithotripsy (ESWL) unit, there were 41 renal units (36 patients) with pretreatment stone burdens greater than 3.0 cm. These calculi were managed by initial percutaneous nephrolithotomy (PCN) followed by ESWL of residual fragments (Group I), primary ESWL with pretreatment ureteral stenting (Group II), or primary ESWL without stenting (Group III). The most common complication of PCN was sepsis, which occurred in 4 of the 12 cases. Results were analyzed at 3 months: greater than 95% stone removal was achieved in 10/12 (83%) in Group I,15/21 (71%) in Group II, and 7/8 (88%) in Group III. Retained ureteral stone fragments was the most common complication, occurring in 1 (8%) Group I, 7 (33%) Group II, and 5 (62%) Group III. Six of the seven patients in Group II had had their stents removed before the development of retained ureteral stone fragments, so the risk of this complication in the presence of a ureteral stent was actually 1 in 15 (6.6%). Of the nine cases with a residual stone burden exceeding 5% of the original, the fragments were located in the lower pole calices in 4 (44%). Our results indicate a similar stone clearance rate for stones greater than 3 cm by using either a PCN and ESWL combination or primary ESWL but a significantly higher incidence of Steinstrasse in cases treated by primary ESWL without ureteral stenting. Lower caliceal components of large stones are poorly cleared by ESWL monotherapy and hence better managed by PCN.