Is there a role for magnetic resonance imaging in renal trauma?

BACKGROUND: Computed tomography (CT) has been the most informative imaging method in renal trauma. Despite the good sensitivity of magnetic resonance imaging (MRI) to the presence of hematoma, edema and ischemia, MRI has not been widely studied in patients with renal trauma. The present study was initiated to evaluate the role of MRI in patients with renal trauma.

METHODS: Between June 1998 and September 1999, CT and MRI were prospectively performed on 12 patients who suffered from renal trauma and the results reviewed.

RESULTS: The presence and size of perirenal hematoma could be detected by both CT and MRI. Magnetic resonance imaging could differentiate intrarenal hematoma from perirenal hematoma more accurately, and provided additional information about the hematoma as T1- and T2-weighted MRI were able to determine recent bleeding in the hematoma by regional differences in signal intensity. Magnetic resonance imaging clearly revealed renal fracture with non-viable fragment and detected focal renal laceration that was not detected on CT due to perirenal hematoma associated with renal infarction. However, although MRI had many advantages over CT, it had also major drawbacks, which were that it required longer imaging time and increased the cost.

CONCLUSIONS: Magnetic resonance imaging may be useful in renal trauma. However, it is suggested that MRI should be limited to carefully selected patients, such as those with severe renal injury or equivocal findings on CT.