DIFFUSION-WEIGHTED MRI CHARACTERIZES THE ISCHEMIC LESION IN TRANSIENTGLOBAL AMNESIA

We present a patient with transient global amnesia (TGA) whose diffusi on-weighted MRI (DWI) showed increased signal in the splenium of the c orpus callosum and in the left parahippocampal gyrus. The absence of h igh signal on the corresponding apparent diffusion coefficient (ADC) i mages supports the diagnosis of an acute infarction. This finding prov ides a temporal relation between cerebral ischemia and infarction in t he territory of posterior cerebral artery and in certain cases of TGA. An early means of detecting ischemia in TGA by DWI may influence clin ical decisions made in patient evaluation and management.