Transient Global Amnesia. Evidence against vascular ischemic etiology from diffusion weighted imaging.
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.
Huber
R
R
Department of Neurology, University of Ulm, Steinhövelstr. 1, 89075 Ulm, Germany.
Aschoff
A J
AJ
Ludolph
A C
AC
Riepe
M W
MW
D000328:Adult; D000368:Aged; D020236:Amnesia, Transient Global / Q000209:etiology* / Q000473:pathology* / Q000503:physiopathology; D002545:Brain Ischemia / Q000473:pathology* / Q000503:physiopathology; D002536:Cerebral Arteries / Q000473:pathology* / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000502:physiology; D005260:Female; D006624:Hippocampus / Q000098:blood supply* / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D008279:Magnetic Resonance Imaging / Q000592:standards; D008297:Male; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D012189:Retrospective Studies; D012307:Risk Factors