Relations between VSRAD-based parahippocampal atrophy and results of neuropsychological tests in patients with Alzheimer's disease and in those with mild cognitive impairment

The objective of this study was to clarify the utility of VSRAD (Voxel-based Specific Regional analysis system for Alzheimer's Disease) for the diagnosis of Alzheimer's Disease (AD) or AD-related studies, correlations between VSRAD-based parahippocampal atrophy and results of neuropsychological tests were investigated. Subjects comprised 18 and 12 patients with probable AD and those with mild cognitive impairment (MCI) due to a cerebral degeneration near AD, respectively. Neuropsychological tests consisted of Alzheimer's Disease Assessment Scale (ADAS)-J cog., Hasegawa Dementia Scale-Revised (HDS-R), Wechsler Adult Intelligent Scale-Revised or -IIIrd (WAIS-R/-III) and Wechsler Memory Scale-Revised (WMS-R). Subjects received these tests within one month before or after cranial MRI scans, and correlations between Z-scores of VSRAD reflecting the parahippocampal atrophy and results of these neuropsychological tests were statistically examined. The Z-scores had a significant positive correlation with scores of ADAS (p=.0129) and an inverse correlation with scores of ''Information'' as a subtest of WAIS-R/-III (p=.0294). Further, the Z-scores showed a tendency to weak, inverse correlations with the scores of HDS-R, ''Similarity'' as a subtest of WAIS-R/-III and ''Visual Reproduction II'' as a subtest of WMS-R (p=.0532, .0635, and .0609, respectively). Usefulness of VSRAD for the diagnosis of AD was indicated by the significant correlations hoted with ADAS and HDS-R, and it was further suggested that parahippocampal atrophy was related to semantic and visual memory impairments of AD, judging from the correlations with subtests of WAIS-R/-III and WMS-R. (author)