LIMITATIONS OF ROUTINE SPIRAL COMPUTERIZED-TOMOGRAPHY IN THE EVALUATION OF BLUNT RENAL TRAUMA

Purpose: We have observed that injury to the renal collecting system m ay be missed during routine abdominal spiral computerized tomography ( CT) for trauma. A definitive protocol for spiral CT has been establish ed to identify all cases of renal collecting system injury. Materials and Methods: A retrospective review of 35 consecutive cases of blunt r enal trauma evaluated with spiral CT between 1994 and 1997 at our Leve l I trauma center was performed. Each patient received 100 cc intraven ous contrast at 2 cc per second. There was a 60-second delay after the start of contrast infusion before scanning was initiated. Results: Of the 35 cases 3 (8.6%) injuries to the renal collecting system were de tected on delayed scans obtained after the initial CT failed to demons trate contrast extravasation. Therefore, at our institution we have mo dified the protocol for spiral CT for abdominal trauma by repeating sc ans of the kidneys after the initial scans are completed. Conclusions: Injury to the renal collecting system may be missed during routine sp iral CT, thereby incorrectly under staging renal trauma. In all cases of suspected blunt renal trauma evaluated with spiral CT repeat scans of the kidneys should be performed.