Parkinson’s disease (PD), a chronic neurodegenerative disease, is characterized by sensorimotor and cognitive deficits. Previous diffusion tensor imaging (DTI) studies found abnormal DTI metrics in white matter bundles, such as the corpus callosum, cingulate, and frontal-parietal bundles, in PD patients. These studies mainly focused on alterations in microstructural features of long-range bundles within the deep white matter (DWM) that connects pairs of distant cortical regions. However, less is known about the DTI metrics of the superficial white matter (SWM) that connects local cortical regions in PD patients. To determine whether the DTI metrics of the SWM were different between the PD patients and the healthy controls, we recruited DTI data from 34 PD patients and 29 gender- and age-matched healthy controls. Using a probabilistic tractographic approach, we first defined a population-based SWM mask across all the subjects. Using a tract-based spatial statistical (TBSS) analytic approach, we then identified the SWM bundles showing abnormal DTI metrics in the PD patients. We found that the PD patients showed significantly lower DTI metrics in the SWM bundles connecting the sensorimotor cortex, cingulate cortex, posterior parietal cortex (PPC), and parieto-occipital cortex than the healthy controls. We also found that the clinical measures in the PD patients was significantly negatively correlated with the fractional anisotropy in the SWM (FA_SWM) that connects core regions in the default mode network (DMN). The FA_SWM in the bundles that connected the PPC was significantly positively correlated with cognitive performance in the PD patients. Our findings suggest that SWM may serve as the brain structural basis underlying the sensorimotor deficits and cognitive degeneration in PD patients.

帕金森病 (PD) 是一种慢性神经退行性疾病，以感觉运动和认知缺陷为特征。先前的扩散张量成像 (DTI) 研究发现 PD 患者的白质束（例如胼胝体、扣带回和额顶束）中的 DTI 指标异常。这些研究主要集中在连接成对的远距离皮层区域的深部白质 (DWM) 内远程束的微观结构特征的改变。然而，对于连接 PD 患者局部皮质区域的浅表白质 (SWM) 的 DTI 指标知之甚少。为了确定 PD 患者和健康对照之间 SWM 的 DTI 指标是否不同，我们从 34 名 PD 患者和 29 名性别和年龄匹配的健康对照中招募了 DTI 数据。使用概率牵引图方法，我们首先在所有受试者中定义了基于人群的 SWM 掩码。使用基于区域的空间统计 (TBSS) 分析方法，我们随后确定了 SWM 束，显示 PD 患者的 DTI 指标异常。我们发现 PD 患者在连接感觉运动皮层、扣带皮层、后顶叶皮层 (PPC) 和顶枕皮层的 SWM 束中的 DTI 指标显着低于健康对照组。我们还发现 PD 患者的临床测量值与 SWM 中的分数各向异性显着负相关（然后，我们确定了在 PD 患者中显示异常 DTI 指标的 SWM 包。我们发现 PD 患者在连接感觉运动皮层、扣带皮层、后顶叶皮层 (PPC) 和顶枕皮层的 SWM 束中的 DTI 指标显着低于健康对照组。我们还发现 PD 患者的临床测量值与 SWM 中的分数各向异性显着负相关（然后，我们确定了在 PD 患者中显示异常 DTI 指标的 SWM 包。我们发现 PD 患者在连接感觉运动皮层、扣带皮层、后顶叶皮层 (PPC) 和顶枕皮层的 SWM 束中的 DTI 指标显着低于健康对照组。我们还发现 PD 患者的临床测量值与 SWM 中的分数各向异性显着负相关（FA _SWM ) 连接默认模式网络 (DMN) 中的核心区域。连接 PPC 的束中的FA _SWM与 PD 患者的认知表现显着正相关。我们的研究结果表明，SWM 可能是 PD 患者感觉运动缺陷和认知退化的大脑结构基础。