Yonsei Med J.  2009 Apr;50(2):211-214.

Higher Lesion Detection by 3.0T MRI in Patient with Transient Global Amnesia

• Lee SY
• Kim WJ
• Suh SH
• Oh SH
• Lee KY

Abstract

PURPOSE
Transient global amnesia (TGA) patients were retrospectively reviewed to determine the usefulness of high-field strength MRI in detecting probable ischemic lesions in TGA. MATERIALS AND METHODS: We investigated the lesion detection rate in patients with TGA using 1.5T and 3.0T MRI. Acute probable ischemic lesions were defined as regions of high-signal intensity in diffusion weighted image with corresponding low-signal intensity in apparent diffusion coefficient map. RESULTS: 3.0T MRI showed 11 out of 32 patients with probable ischemic lesions in the hippocampus with mean lesion size of 2.8 +/- 0.6 mm, whereas 1.5T MRI detected no lesion in any of 11 patients. There were no significant differences in clinical characteristics between the groups of 1.5 and 3.0T MRI. CONCLUSION: High-field strength MRI has a higher detection rate of probable ischemic lesions than low-field strength MRI in patients with TGA.

Keyword

Transient global amnesia; ischemia; MRI

MeSH Terms

Adult
Aged
Aged, 80 and over
Amnesia, Transient Global/*diagnosis/pathology
Female
Humans
Magnetic Resonance Imaging
Male
Middle Aged
Retrospective Studies
Young Adult

Figure

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  Fig. 1 Representative 3.0T MRI of 2 TGA patients shows small high-signal intensity lesions in the hippocampus on DWI (arrow) and corresponding low-signal intensity lesions on ADC map (arrow head). TGA, transient global amnesia; DWI, diffusion weighted imaging; ADC, apparent diffusion coefficient.

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