Ueno Hiroki, Naka Hiromitsu, Ohshita Tomohiko, Wakabayashi Shinichi, Matsumoto Masayasu
Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical Sciences, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
Hiroshima J Med Sci. 2010 Dec;59(4):77-81.
The etiology of transient global amnesia (TGA) is not well understood. MR studies, including studies using diffusion-weighted imaging (DWI), have been used to investigate the pathophysiology of TGA, and focal hippocampal lesions have been detected in some studies. The aim of this study was to investigate serial changes in MR images from the patients with TGA. In seven TGA patients, serial MRI scans (from the same day of the onset to several days after the onset of symptoms) using a 1.5-T MR unit were prospectively evaluated. In four patients, the duration of TGA was over 12 hr. Three of those patients showed small punctate hippocampal hypersensitivity with decreased ADC values on DW images. These lesions were detected in the postacute phase (a time window of 24 - 48 hr after the onset of symptoms). In follow-up studies performed several days after the onset of symptoms, DWI lesions had disappeared in the subacute phase (7-10 days after the TGA episode). The delayed hippocampal lesion on DW images with 1.5-T MRI in patients with TGA appears to be associated with longer duration of symptoms, to persist for several days and to disappear in the chronic phase.
短暂性全面性遗忘症（TGA）的病因尚不完全清楚。包括使用扩散加权成像（DWI）的研究在内的磁共振成像（MR）研究已被用于探究TGA的病理生理学，并且在一些研究中检测到了海马局灶性病变。本研究的目的是调查TGA患者MR图像的系列变化。对7例TGA患者使用1.5-T磁共振设备进行了前瞻性评估，从发病当天至症状发作后数天进行系列MRI扫描。在4例患者中，TGA持续时间超过12小时。其中3例患者在DWI图像上显示海马区有小的点状高信号，表观扩散系数（ADC）值降低。这些病变在急性后期（症状发作后24 - 48小时的时间窗）被检测到。在症状发作数天后进行的随访研究中，DWI病变在亚急性期（TGA发作后7 - 10天）消失。TGA患者使用1.5-T MRI时，DW图像上延迟出现的海马病变似乎与症状持续时间较长有关，持续数天并在慢性期消失。
