RENAL DAMAGE AFTER EXTRACORPOREAL SHOCK-WAVE LITHOTRIPSY DETECTED BY MAGNETIC RESONANCE IMAGING

The acute effects of extracorporeal Shock-wave lithotripsy (ESWL) on morphology of the renal parenchyma were evaluated by Magnetic Resonance Imaging (MRI) in 15 kidneys, before and immediately after (within 24 hours) ESWL in 11 cases. The renal parenchymal damages were observed by MRI as the changes of signal intensity of renal cortex and medulla, perirenal fluid, loss of corticomedullar differentiation, and other renal traumas. Loss of corticomedullar differentiation was seen in 9/11 cases and peripheral fluid of the kidney was seen in 4/11 cases. Irregular and edematous changes of renal capsula were seen in 5/11 cases. Obvious abnormal findings indicated renal trauma were not observed in this study. Several MRI findings may transient and reversible changes and the morpholigic changes detected by MRI may attributed to renal parenchymal obstruction and edema and decreasing of renal capillary flow, such as in renal contusion. It is concluded that MRI is very sensitive and the best technique to detect the effects and clinical trouble of ESWL.