Yoshida Tomokatsu, Yasuda Rei, Mizuta Ikuko, Nakagawa Masanori, Mizuno Toshiki
Department of Neurology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Eur Neurol. 2017;77(5-6):296-302. doi: 10.1159/000475661. Epub 2017 Apr 28.
Brain MRI in adult patients with Alexander disease (AxD) mainly shows atrophy in the medulla oblongata. However, currently there is no quantitative standard for assessing this atrophy. In this study, we quantitatively evaluated the brain stem of AxD patients with glial fibrillary acidic protein (GFAP) mutation using conventional MRI to evaluate its usefulness as an aid to diagnosing AxD in daily clinical practice. Nineteen AxD patients with GFAP mutation were compared with 14 patients negative for GFAP mutation in whom AxD was suspected due to "atrophy of the medulla oblongata." In the GFAP mutation-positive group, the sagittal diameter of the medulla oblongata, the ratio of the diameter of the medulla oblongata to that of the midbrain (MO/MB), and the ratio of the sagittal diameter of the medulla oblongata to that of the pons (MO/Po) were significantly smaller compared to those of the GFAP mutation-negative group (p < 0.01). The sensitivity and specificity of each parameter were 87.5 and 92.3%, 91.7 and 81.3%, and 88.2 and 100% with a sagittal diameter of the medulla oblongata <9.0 mm, MO/MB <0.60, and sagittal MO/Po <0.46, respectively. These parameters can provide very useful information to differentially diagnose AxD from other disorders associated with brain stem atrophy in adult patients.
成年亚历山大病（AxD）患者的脑部磁共振成像（MRI）主要显示延髓萎缩。然而，目前尚无评估这种萎缩的定量标准。在本研究中，我们使用传统MRI对胶质纤维酸性蛋白（GFAP）突变的AxD患者的脑干进行了定量评估，以评估其在日常临床实践中辅助诊断AxD的效用。将19例GFAP突变的AxD患者与14例因“延髓萎缩”而疑似AxD但GFAP突变阴性的患者进行比较。在GFAP突变阳性组中，延髓矢状径、延髓直径与中脑直径之比（MO/MB）以及延髓矢状径与脑桥矢状径之比（MO/Po）均显著小于GFAP突变阴性组（p < 0.01）。延髓矢状径<9.0 mm、MO/MB <0.60和矢状MO/Po <0.46时，各参数的敏感性和特异性分别为87.5%和92.3%、91.7%和81.3%、88.2%和100%。这些参数可为成年患者鉴别诊断AxD与其他伴有脑干萎缩的疾病提供非常有用的信息。
