Department of Clinical Neurosciences, National Institute of Mental Health & Neurosciences, Bangalore, India.
Department of Neurology, National Institute of Mental Health & Neurosciences, Bangalore, India.
Acta Neurol Scand. 2021 Apr;143(4):430-440. doi: 10.1111/ane.13372. Epub 2020 Nov 22.
Progressive supranuclear palsy-Richardson syndrome (PSP-RS) is characterized by symmetrical parkinsonism with postural instability and frontal dysfunction. This study aims to use the whole brain structural connectome (SC) to gain insights into the underlying disconnectivity which may be implicated in the clinical features of PSP-RS.
Sixteen patients of PSP-RS and 12 healthy controls were recruited. Disease severity was quantified using PSP rating scale (PSPRS), and mini-mental scale was applied to evaluate cognition. Thirty-two direction diffusion MRIs were acquired and used to compute the structural connectome of the whole brain using deterministic fiber tracking. Group analyses were performed at the edge-wise, nodal, and global levels. Age and gender were used as nuisance covariates for all the subsequent analyses, and FDR correction was applied.
Network-based statistics revealed a 34-edge network with significantly abnormal edge-wise connectivity in the patient group. Of these, 25 edges were cortical connections, of which 68% were frontal connections. Abnormal deep gray matter connections were predominantly comprised of connections between structures of the basal ganglia. The characteristic path length of the SC was lower in PSP-RS, and nodal analysis revealed abnormal degree, strength, local efficiency, betweenness centrality, and participation coefficient in several nodes.
Significant alterations in the structural connectivity of the whole brain connectome were observed in PSP-RS. The higher degree of abnormality observed in nodes belonging to the frontal lobe and basal ganglia substantiates the predominant frontal dysfunction and parkinsonism observed in PSP-RS. The findings of this study support the concept that PSP-RS may be a network-based disorder.
进行性核上性麻痹 - 理查森综合征（PSP-RS）的特征是对称帕金森病伴有姿势不稳和额功能障碍。本研究旨在使用全脑结构连接组（SC）深入了解潜在的连接中断，这可能与 PSP-RS 的临床特征有关。
招募了 16 名 PSP-RS 患者和 12 名健康对照者。使用 PSP 评分量表（PSPRS）量化疾病严重程度，使用迷你精神状态量表评估认知。获得 32 个方向扩散 MRI 并用于使用确定性纤维跟踪计算全脑结构连接组。在边缘、节点和全局水平进行组分析。在所有后续分析中，将年龄和性别用作混杂协变量，并应用 FDR 校正。
网络基础统计分析显示，患者组存在 34 个边缘网络，边缘连接存在明显异常。其中，25 个边缘是皮质连接，其中 68%是额连接。异常的深部灰质连接主要由基底节结构之间的连接组成。SC 的特征路径长度在 PSP-RS 中较低，节点分析显示几个节点的异常程度、强度、局部效率、介数中心性和参与系数。
在 PSP-RS 中观察到整个脑连接组的结构连接发生了显著变化。属于额叶和基底节的节点异常程度较高，证实了 PSP-RS 中观察到的主要额功能障碍和帕金森病。本研究的结果支持 PSP-RS 可能是一种基于网络的疾病的概念。
