[Accuracy of VSRAD Analysis Using Scout Images: Comparison with Conventional 3D-T₁WI]

The voxel-based specific regional analysis system for Alzheimer's disease (VSRAD), which targets volume loss in medial temporal lobe, was developed as a sensitive diagnostic tool to detect early stages of Alzheimer's disease. However, conventional three-dimensional T₁ -weighted image (3D-T₁WI) for VSRAD analysis acquires relatively long acquisition time. Recently, it became possible to acquire Scout images (Scout) for positioning as a 3D image in a short time. The aim of this study was to determine whether Scout was reliable in VSRAD. We measured voxel-based analysis of gray matter volume using VBM and Z-score of medial temporal lobe atrophy using VSRAD advance 2 from conventional 3D-T₁WI and Scout. It showed significantly different gray mass between conventional 3D-T₁WI and Scout. However, there was no significant difference in Z-score (p=0.41). The Z-scores measured from Scout and conventional 3D-T₁WI were significantly correlated (r=0.96, p<0.05). There is a possibility that Scout can be used to detect brain morphometry abnormalities instead of conventional 3D-T₁WI in the VSRAD analysis.