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Decrease in cortical benzodiazepine receptors in symptomatic patients with leukoaraiosis: a positron emission tomography study.

M Ihara·H Tomimoto·K Ishizu·T Mukai·H Yoshida·N Sawamoto·M Inoue·T Doi·K Hashikawa·J Konishi·H Shibasaki·H Fukuyama
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Abstract

BACKGROUND AND PURPOSE: [11C]flumazenil (FMZ), a ligand that selectively binds to the central benzodiazepine receptor in the neuronal membrane, is useful for evaluating neuronal viability in a positron emission tomography (PET) scan. Using this ligand, we investigated whether there was a correlation between neuronal integrity in various brain structures and dementia in patients with leukoaraiosis. METHODS: Twelve patients with extensive leukoaraiosis on magnetic resonance imaging were divided into groups of patients with or without dementia. Based on a 2-compartment, 2-parameter model that included metabolite-corrected arterial input and PET-measured cerebral radioactivity, the distribution volume of FMZ (FMZ-V(d)) was calculated in various regions of interest by nonlinear curve fitting. Additionally, tracer kinetic analysis was applied for voxel-by-voxel quantification of FMZ-V(d), and data analysis was performed by statistical parametric mapping. RESULTS: The presence of dementia was associated with a reduced FMZ-V(d) in widespread areas of the cerebral cortex, including the bilateral frontopolar and frontal/insular areas, the left temporo-occipital border areas, and the left marginal cortical areas. CONCLUSIONS: Differences in neuronal integrity in the cerebral cortex might determine whether patients with leukoaraiosis become symptomatic or not.

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AgedCerebral CortexCerebrovascular CirculationDementia, VascularFemaleFlumazenilHumansLigandsMagnetic Resonance ImagingMaleOxygen ConsumptionRadioactive TracersReceptors, GABA-ATomography, Emission-ComputedJournal ArticleResearch Support, Non-U.S. Gov't

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M Ihara, H Tomimoto, K Ishizu, T Mukai, H Yoshida, N Sawamoto, M Inoue, T Doi, K Hashikawa, J Konishi, H Shibasaki, H Fukuyama. 2004-03-04. Decrease in cortical benzodiazepine receptors in symptomatic patients with leukoaraiosis: a positron emission tomography study.. https://doi.org/10.1161/01.str.0000122624.32167.e0

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