Detection of regional pulmonary perfusion deficit of the occluded lung using arterial spin labeling in magnetic resonance imaging

Detection of regional perfusion deficit in the lung has been demonstrated u sing an arterial spin labeling technique called now-sensitive alternating i nversion recovery with an extra radiofrequency pulse (FAIRER). A pulmonary artery was occluded using a nondetachable balloon catheter to simulate an a cute pulmonary embolism in 3 of 10 rabbits. Inflating the balloon occludes the artery, and deflating the balloon allows for reperfusion. Perfusion ima ging was performed pre-occlusion, during occlusion, and after reperfusion, Signal enhancement due to perfusion of the pulmonary parenchyma was observe d in the perfusion images with negligible artifacts. The perfusion deficit of the pulmonary parenchyma was detected distal to the site of occlusion in all three rabbits. Return of the pulmonary parenchymal perfusion was obser ved after reperfusion. Magnetic resonance imaging using FAIRER can detect s ignal loss due to absence of perfusion caused by pulmonary embolism. (C) 20 00 Wiley-Liss, Inc.