The etiology of Transient Global Amnesia (TGA) is still obscure. Diffusion-Weighted-Imaging (DWI) provides conflicting evidence
concerning a possible vascular ischemic cause in mesiotemporal structures including the hippocampal region. The question remains
open whether conflicting observations resulted from different observation times. DWI was performed at a time interval with
known sensitivity for detection of ischemia. Ten patients (5 male, 5 female; mean age of 63 ± 9, range 41–71 years) with typical
TGA were investigated at an average delay of 18 hours (range 6 to 44 hours) between onset of symptoms and magnetic resonance
imaging (transversal DW-, T1W- and T2W-MRI). Five patients received apparent-diffusion-coefficient (ADC)-mapping. Cerebrovascular
studies (ECG, TTE and extra/transcranial dopplersonographic and duplexultrasonic investigation) and EEG were normal in all
patients. DW-MRI-sequences and ADC-maps, if performed, were normal in all patients. Conventional T2W-MRI in 3 out of 10 patients
showed microangiopathic subcortical changes and lacunar strokes of older origin. We conclude that TGA does not result from
a vascular ischemic etiology in the majority of cases.
Key words transient global amnesia - ischemia - diffusion weighted MRI - etiology
Received: 13 February 2002, Received in revised form: 14 May 2002, Accepted: 22 May 2002
Correspondence to Dr. Matthias W. Riepe