Preoperative evaluation of living renal donors: value of contrast-enhanced 3D magnetic resonance angiography and comparison of three rendering algorithms
OBJECTIVE The purpose of this study is to clarify the most useful technique of MR imaging in demonstrating the collateral venous pathways due to portal hypertension. SUBJECTS Twenty-eight cirrhotic patients with collateral venous pathways due to portal hypertension and three patients without them were studied. We evaluated the detectability of collateral vessels of flow-enhanced transverse MR images by time of flight effect, projection MR angiography using the maximum intensity projection technique and three-dimensional (3D) computer graphic images, by using the arterial portography as the standard. RESULTS Flow-enhanced transverse MR images showed 98% of the collateral vessels detected by angiography, however, the connection of each vessel was obscure. Fully 81% of the collateral vessels were seen by projection MR angiography, and 98% of them by the 3D computer graphic images. CONCLUSION The detectability of collateral vessels of 3D computer graphic imaging was better than that of the projection MR angiography and was as accurate as that of transverse MR imaging. 3D Computer graphic images provided complex anatomical information in a more easily understood fashion than either transverse MR images or projection MR angiography.