Bilateral hippocampal abnormalities on diffusion-weighted MRI in transient global amnesia: report of a case.

The pathophysiology of transient global amnesia (TGA) is still speculative. Recently, diffusion-weighted image (DWI) of magnetic resonance imaging (MRI) documented tiny lesions in the hippocampus of patients with TGA in the acute stage. Most studies reported unilateral lesions on MRI. We present one patient of TGA with high signal-intensity lesions in bilateral hippocampus on DWI at the acute stage. The serial findings of brain MRI support the ischemic nature of TGA. Related mechanism about TGA is discussed.