[Computerized tomography follow-up after percutaneous renal lithotripsy].

Even though extracorporeal shock wave lithotripsy (ESWL) is nowadays considered the treatment of choice for the majority of upper urinary tract calculi, percutaneous stone removal will continue to be an alternative treatment method in selected cases. Therefore, percutaneous techniques must not be forgotten by the interventional radiologist. In order to assess the effects and the potential damage caused by this interventional procedure to kidney and perirenal tissues, CT was performed on 20 patients before and after percutaneous nephrolithotripsy. In the cases where no complications occurred during the maneuver, post-nephrolithotripsy scans demonstrated low incidence of significant renal abnormalities. Thickening of pararenal fascia (8 patients) and irregular renal outline (10 patients) were our most frequent findings. In 5 patients we found edema of the pyelo-ureteral junction, in 3 thickening of the bridging perinephric septa and retained stone fragments, in 2 perirenal hematomas, in one a subcapsular fluid collection. Urinoma with pelvic laceration was demonstrated in the only patient in whom the maneuver presented marked technical problems. On the basis of this series of pre- and post-nephrolithotripsy CT scans of treated kidneys, the authors conclude that this percutaneous technique is quite atraumatic.