Table IV. Conspicuous MRI/CT findings in patients suspected of having AD. (See list of abbreviations at the beginning of this article) .

Findings	Consider alternative diagnoses
No hippocampal atrophy	Normal aging; MCI, FTD, PSP, CBD
Unilateral hippocampal atrophy	SD
Extreme hippocampal atrophy	SD; argyrophilic grain disease
Abundant small-vessel disease	VaD; CAA; amyloid angiopathy
Unilateral cerebral atrophy	CBD
No abnormalities	Normal aging; early stage AD
Striking asymmetry temporal region	SD, PA