FUNCTIONAL MR IN THE EVALUATION OF DEMENTIA - CORRELATION OF ABNORMALDYNAMIC CEREBRAL BLOOD-VOLUME MEASUREMENTS WITH CHANGES IN CEREBRAL METABOLISM ON POSITRON EMISSION TOMOGRAPHY WITH FLUDEOXYGLUCOSE F-18

PURPOSE: To determine whether magnetic susceptibility functional MR im aging of cerebral blood volumes provides information similar to fludeo xyglucose F 18 positron emission tomography (PET) brain images in pati ents undergoing evaluation for dementia. METHODS: Ten subjects were st udied with both PET and functional MR. Clinical diagnoses included pro bable Alzheimer disease (n = 5), possible Alzheimer disease (n = 1), P ick disease (n = 2), and primary progressive aphasia (n = 2). The stud ies were quantitatively evaluated by coregistration of PET and functio nal MR images followed by regression analyses of corresponding regions of interest. Qualitatively, each brain was categorized into eight reg ions, and each was classified as normal or abnormal by visual inspecti on. RESULTS: Correlation coefficients between registered functional MR and PET images were excellent (mean, r = 0.58) in most of the cerebru m. Significant correlations were observed in 72 of 74 brain sections. Qualitatively, 16 brain regions were judged to be abnormal by both MR imaging and PET; 46 regions were normal by both; 10 regions were abnor mal by PET only; and 8 regions were abnormal only by functional MR. Th e concordance between functional MR and PET was 78%, which was highly significant. CONCLUSION: Cerebral blood volumes images derived from ma gnetic susceptibility (functional MR) provide information similar to f ludeoxyglucose F 18 PET images in demented patients undergoing evaluat ion for dementia.