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

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.

Lesion detectability on diffusion-weighted imaging in transient global amnesia: the influence of imaging timing and magnetic field strength

“…There was only one study evaluating the potential influence of the magnetic field strength on the lesion detectability of DWI in TGA [30]. However, the precise comparison of the influence of the magnetic field strength was difficult to assess in their study because the imaging parameters including the matrix, field of view, section thickness, and resulting voxel size were different between 1.5-and 3-T examinations.…”

Diagnostic Yield of Diffusion-Weighted Brain Magnetic Resonance Imaging in Patients with Transient Global Amnesia: A Systematic Review and Meta-Analysis

“…The full-text review further excluded 6 more articles: 3 that did not include DWI, 1 that was not written in English, 1 that included fewer than 5 patients, and 1 that included incomplete information. Finally, 22 eligible articles (1732 patients) were included in this meta-analysis [2,[6][7][8][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34]. Figure 1 shows the detailed study selection process.…”

Transient Global Amnesia: A Brief Review and Update

“…Other investigators have found frontal lobe abnormalities by diffusionweighted MRI [38] or PET imaging [39]. Several reports have described diffusion-weighted imaging (DWI) lesions in a high proportion of TGA cases, especially hippocampal abnormalities [39][40][41][42]. The last article cited reported a higher detection rate, 11/32 compared with 0/32 with 3 T MRI, compared with 1.5 T. The experience in our hospital has been less positive, in that most patients have had negative DWI MRI scans.…”