Analysis of the Results of Percutaneous Nephrolithotomy for Staghorn Calculi: Based on Stone Surface Area

Hwang, Tae Kon; Cho, Su Yeon

Abstract

Though high stone free rates were reported with ESWL monotherapy or anatrophic nephrolithotomy, percutaneous nephrolithotomy with or without ESWL appears to be the procedure of choice for most staghorn calculi. A total of 41 patients with staghorn calculi underwent percutaneous nephrolithotomy(PNL) alone or primary percutaneous debulking followed by extracorporeal shock wave lithotripsy(ESWL) of residual stone fragments. For the objective analysis of the results of PNL stone removal rate was calculated with stone surface area which was determined by computer analyzer. For staghorn calculi smaller than 2000 mm2(38/41), a mean stone removal rate of about 90% was achieved in the PNL. When stone surface area exceeded 2000 mm2(3,41), the mean stone removal rate was 78.8%. The stone removal rates stratified by stone surface area were not significantly different. The stone free rate was 31.7% in the PNL only but 75.6% in the PNL with or without ESWL. The higher mean stone removal rate and stone free rate was achieved in the kidneys with non-dilated collecting system than those with hydronephrosis, but it was not statistically significant.