Gatto R G, Mustafi S M, Amin M Y, Mareci T H, Wu Yu-Chien, Magin R L
Funct Neurol. 2018 Jul/Sept;33(3):155-163.
Neurite orientation dispersion and density imaging (NODDI), a MRI multi-shell diffusion technique, has offered new insights for the study of microstructural changes in neurodegenerative diseases. Mainly, the present study aimed to determine the connection between NODDI-derived parameters and changes in white matter (WM) abnormalities at early stages of amyotrophic lateral sclerosis (ALS). Spinal cords from ALS mice (G93A-SOD1 mice) were scanned in a Bruker Avance III HD 17.6T magnet. Fluorescent axonal-tagged mice (YFP, G93A-SOD1 mice) were used for quantitative histological analysis. NODDI showed a decrease in intra-cellular volume fraction (-24%) and increases in orientation dispersion index (+35%) and isotropic volume fraction (+33%). In addition, histoathological results demonstrated a reductions in axonal area (-11%) and myelin content (-29%). A histological decrease in WM intra-axonal space (-71%) and an increase in the extra-axonal compartment (+22%) were also detected. Our studies demonstrate that NODDI may be a suitable technique for detecting presymptomatic spinal cord WM microstructural degeneration in ALS.
神经突方向离散与密度成像（NODDI）是一种磁共振成像多壳层扩散技术，为神经退行性疾病微观结构变化的研究提供了新的见解。主要而言，本研究旨在确定肌萎缩侧索硬化症（ALS）早期阶段NODDI衍生参数与白质（WM）异常变化之间的联系。对ALS小鼠（G93A-SOD1小鼠）的脊髓在布鲁克Avance III HD 17.6T磁体中进行扫描。使用荧光轴突标记小鼠（YFP，G93A-SOD1小鼠）进行定量组织学分析。NODDI显示细胞内体积分数降低（-24%），方向离散指数增加（+35%），各向同性体积分数增加（+33%）。此外，组织病理学结果显示轴突面积减少（-11%）和髓鞘含量减少（-29%）。还检测到WM轴突内空间的组织学减少（-71%）和轴突外间隙的增加（+22%）。我们的研究表明，NODDI可能是检测ALS症状前脊髓WM微观结构退化的合适技术。
