Kamiya Kouhei, Hanashiro Sayori, Kano Osamu, Uchida Wataru, Kamagata Koji, Aoki Shigeki, Hori Masaaki
Department of Radiology, Faculty of Medicine, Toho University, Tokyo, Japan.
Department of Radiology, Faculty of Medicine, Juntendo University, Tokyo, Japan.
Magn Reson Med Sci. 2025 Jan 1;24(1):122-132. doi: 10.2463/mrms.mp.2023-0138. Epub 2024 May 29.
Here, we aimed to characterize the cortical and subcortical microstructural alterations in the brains of patients with amyotrophic lateral sclerosis (ALS). In particular, we compared these features between bulbar-onset ALS (b-ALS) and limb-onset ALS (l-ALS).
Diffusion MRI data (b = 0, 700, 2000 ms/mm, 1.7-mm isotropic voxel) from 28 patients with ALS (9 b-ALS and 19 l-ALS) and 17 healthy control subjects (HCs) were analyzed. Diffusional kurtosis imaging (DKI) metrics were sampled at the mid-cortical and subcortical surfaces. We used permutation testing with a nonparametric combination of mean diffusivity (MD), fractional anisotropy (FA), and mean kurtosis (MK) to assess intergroup differences over the cerebrum. We also carried out an atlas-based analysis focusing on Brodmann Area 4 and 6 (primary motor and premotor areas) and investigated the correlation between MRI metrics and clinical parameters.
At both the mid-cortical and subcortical surfaces, b-ALS was associated with significantly greater MD, smaller FA, and smaller MK in the motor and premotor areas than HC. In contrast, the patients with l-ALS showed relatively moderate differences relative to HCs. The ALS Functional Rating Scale-Revised bulbar subscore was significantly correlated with the diffusion metrics in Brodmann Area 4.
The distribution of abnormalities over the cerebral hemispheres and the more severe microstructural alteration in b-ALS compared to l-ALS were in good agreement with findings from postmortem histology. Our results suggest the feasibility of surface-based DKI analyses for exploring brain microstructural pathologies in ALS. The observed differences between b-ALS and l-ALS and their correlations with functional bulbar impairment support the clinical relevance of DKI measurement in the cortical and juxtacortical regions of patients with ALS.
在此，我们旨在描述肌萎缩侧索硬化症（ALS）患者大脑皮质和皮质下微观结构的改变。特别是，我们比较了延髓起病型ALS（b-ALS）和肢体起病型ALS（l-ALS）之间的这些特征。
分析了28例ALS患者（9例b-ALS和19例l-ALS）以及17名健康对照者（HCs）的扩散MRI数据（b = 0、700、2000 ms/mm，各向同性体素为1.7 mm）。在皮质中部和皮质下表面采集扩散峰度成像（DKI）指标。我们使用排列检验以及平均扩散率（MD）、分数各向异性（FA）和平均峰度（MK）的非参数组合来评估大脑半球间的组间差异。我们还进行了基于图谱的分析，重点关注布罗德曼4区和6区（初级运动区和运动前区），并研究了MRI指标与临床参数之间的相关性。
在皮质中部和皮质下表面，b-ALS患者运动区和运动前区的MD显著更高，FA和MK显著更小，相比之下HCs则无此情况。相比之下，l-ALS患者与HCs相比差异相对较小。ALS功能评定量表修订版的延髓亚评分与布罗德曼4区的扩散指标显著相关。
大脑半球异常的分布以及与l-ALS相比b-ALS中更严重的微观结构改变与尸检组织学结果高度一致。我们的结果表明基于表面的DKI分析对于探索ALS患者脑微观结构病变具有可行性。观察到的b-ALS和l-ALS之间的差异及其与延髓功能损害的相关性支持了DKI测量在ALS患者皮质和皮质下区域的临床相关性。
