Department of Radiology, Juntendo University Graduate School of Medicine, Tokyo, Japan.
Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, Japan.
J Neurosci Res. 2020 May;98(5):936-949. doi: 10.1002/jnr.24584. Epub 2020 Feb 5.
Neurocognitive and psychiatric disorders have significant consequences for quality of life in patients with Parkinson's disease (PD). In the current study, we evaluated microstructural white matter (WM) alterations associated with neurocognitive and psychiatric disorders in PD using neurite orientation dispersion and density imaging (NODDI) and linked independent component analysis (LICA). The indices of NODDI were compared between 20 and 19 patients with PD with and without neurocognitive and psychiatric disorders, respectively, and 25 healthy controls using tract-based spatial statistics and tract-of-interest analyses. LICA was applied to model inter-subject variability across measures. A widespread reduction in axonal density (indexed by intracellular volume fraction [ICVF]) was demonstrated in PD patients with and without neurocognitive and psychiatric disorders, as compared with healthy controls. Compared with patients without neurocognitive and psychiatric disorders, patients with neurocognitive and psychiatric disorders exhibited more extensive (posterior predominant) decreases in axonal density. Using LICA, ICVF demonstrated the highest contribution (59% weight) to the main effects of diagnosis that reflected widespread decreases in axonal density. These findings suggest that axonal loss is a major factor underlying WM pathology related to neurocognitive and psychiatric disorders in PD, whereas patients with neurocognitive and psychiatric disorders had broader axonal pathology, as compared with those without. LICA suggested that the ICVF can be used as a useful biomarker of microstructural changes in the WM related to neurocognitive and psychiatric disorders in PD.
神经认知和精神障碍对帕金森病 (PD) 患者的生活质量有重大影响。在本研究中，我们使用神经丝取向分散和密度成像 (NODDI) 和连接独立成分分析 (LICA) 评估了与 PD 患者神经认知和精神障碍相关的微观结构白质 (WM) 改变。使用基于束的空间统计学和感兴趣束分析，将 NODDI 的指标分别与 20 名和 19 名分别患有和不患有神经认知和精神障碍的 PD 患者以及 25 名健康对照者进行了比较。LICA 被用于对跨测量的个体间变异性进行建模。与健康对照组相比，患有和不患有神经认知和精神障碍的 PD 患者表现出广泛的轴突密度降低（由细胞内体积分数 [ICVF] 表示）。与没有神经认知和精神障碍的患者相比，患有神经认知和精神障碍的患者表现出更广泛的（后部为主）轴突密度降低。使用 LICA，ICVF 对反映广泛轴突密度降低的诊断主要效应具有最高的贡献（59%权重）。这些发现表明，轴突丢失是与 PD 中神经认知和精神障碍相关的 WM 病理的主要因素，而与没有神经认知和精神障碍的患者相比，患有神经认知和精神障碍的患者具有更广泛的轴突病理学。LICA 表明，ICVF 可以用作与 PD 中神经认知和精神障碍相关的 WM 微观结构变化的有用生物标志物。
