Computed tomography after percutaneous renal stone extraction.

Eighty patients were examined with computed tomography (CT) of the kidney and the retroperitoneal space after percutaneous stone extraction. Most examinations were done within a week after the operation. The morphologic changes were usually small or none. In 7 patients minor renal or perirenal fluid collections were found. Their operations had been complicated by bleeding or leakage. In 66 patients CT was compared with conventional radiographs. Residual stones were more often detected by CT. They were usually small. Percutaneous renal stone extraction is considered a safe and efficient method.