title: The prediction of rapid conversion to Alzheimer's disease in mild cognitive impairment using regional cerebral blood flow SPECT.
abstract: Mild cognitive impairment (MCI) comprises a heterogeneous group with a variety of clinical outcomes and they are at risk for developing Alzheimer's disease (AD). The prediction of conversion from MCI to AD using the initial neuroimaging studies is an important research topic. We investigated the initial regional cerebral blood flow (rCBF) measurements using single photon emission computed tomography (SPECT) in individuals with 76 amnesic MCI (52 subjects converted to AD and 24 subjects did not convert to AD at 3-year follow-up) and 57 age- and gender-matched controls. We sought functional profiles associated with conversion to AD, then evaluated the predictive value of the initial rCBF SPECT. As compared with controls, AD converters demonstrated reduced blood flow in the bilateral parahippocampal gyri, precunei, posterior cingulate cortices, bilateral parietal association areas, and the right middle temporal gyrus. Non-converters also demonstrated significant reduction of rCBF in the posterior cingulated cortices and the right caudate nucleus when compared to controls. As compared with non-converters, converters showed reductions of rCBF in the bilateral temporo-parietal areas and the precunei. The logistic regression model revealed that reduced rCBF in the inferior parietal lobule, angular gyrus, and precunei has high predictive value and discriminative ability. Although a cross-validation study is needed to conclude the usefulness of rCBF SPECT for the prediction of AD conversion in individuals with MCI, our data suggest that the initial rCBF SPECT studies of individuals with MCI may be useful in predicting who will convert to AD in the near future.
authors.affiliation: Department of Radiology, National Center Hospital of Mental, Nervous, and Muscular Disorders, National Center of Neurology and Psychiatry, Tokyo, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Hirao
authors.forename: Takashi
authors.initials: T
authors.lastname: Ohnishi
authors.forename: Yoko
authors.initials: Y
authors.lastname: Hirata
authors.forename: Fumio
authors.initials: F
authors.lastname: Yamashita
authors.forename: Takeyuki
authors.initials: T
authors.lastname: Mori
authors.forename: Yoshiya
authors.initials: Y
authors.lastname: Moriguchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Matsuda
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Nemoto
authors.forename: Etsuko
authors.initials: E
authors.lastname: Imabayashi
authors.forename: Minoru
authors.initials: M
authors.lastname: Yamada
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Iwamoto
authors.forename: Kunimasa
authors.initials: K
authors.lastname: Arima
authors.forename: Takashi
authors.initials: T
authors.lastname: Asada
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D000544:Alzheimer Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000523:psychology; D000647:Amnesia / Q000503:physiopathology / Q000523:psychology; D001931:Brain Mapping; D002560:Cerebrovascular Circulation / Q000502:physiology*; D003072:Cognition Disorders / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000523:psychology; D015331:Cohort Studies; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000503:physiopathology / Q000523:psychology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D020534:Parahippocampal Gyrus / Q000098:blood supply; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D015899:Tomography, Emission-Computed, Single-Photon