MEASUREMENT OF CEREBRAL BLOOD-VOLUME WITH SUBTRACTION 3-DIMENSIONAL FUNCTIONAL CT

PURPOSE: To implement a three-dimensional subtraction functional CT te chnique to permit rapid quantitative mapping of regional cerebral bloo d volume (CBV). METHODS: The 3-D functional CT technique was implement ed in a rabbit model using normal and ischemic animals, Two spiral dat a acquisitions were performed, one before and one during biphasic admi nistration of contrast material. CBV maps were then produced on a voxe l-by-voxel basis through the whole brain. RESULTS: The average normal CBV was 3.3+/-0.4 mL/100 g (n=7), and the regional values were 4.5+/-0 .6 mL/100 g for cortical gray matter, 2.5+/-0.6 mL/100 g for white mat ter, and 3.7+/-0.4 mL/100 g for the basal ganglia. The CBVs in ischemi c regions were 1.5+/-0.4 mL/100 g, 0.7+/-0.7 mL/100 g, and 1.8+/-0.9 m L/100 g, respectively. CONCLUSION: Subtraction 3-D functional CT is a fast, potentially cost-effective method with which to assess whole-bra in CBV. Because the data collected in 3-D functional CT imaging also c an be used to produce large-vessel angiograms, its use in a clinical s etting can provide a multiparametric study of cerebrovascular abnormal ities that encompasses both large and small vessel circulations for pa tients being examined for stroke.