School of Biomedical Engineering, University of British Columbia, Vancouver, Canada.
Medical Undergraduate Program, University of British Columbia, Vancouver, Canada.
J Magn Reson Imaging. 2019 Jul;50(1):164-174. doi: 10.1002/jmri.26543. Epub 2018 Nov 15.
White matter (WM) microstructural integrity is important for effective brain functioning and alterations have been shown in many neurodegenerative diseases.
To investigate WM myelin profiles and their relation to clinical features of Parkinson's disease (PD).
Retrospective cross-sectional.
In all, 29 PD subjects and 15 healthy controls.
FIELD STRENGTH/SEQUENCE: Multiecho GRASE with 10 msec echo spacing and echo planar imaging (EPI) diffusion-weighted (b-value = 700 with 32 gradient directions) on a 3T scanner.
Myelin water fraction (MWF) and fractional anisotropy (FA) across 20 WM regions of interest (ROIs) were compared between groups. Partial least squares (PLS) was used to associate MWF and FA with clinical and behavioral measures.
Group comparisons were done using two-sample t-tests. PLS was assessed with permutation tests. Bootstrapping was used to investigate the robustness of imaging features.
No group differences in myelin content could be detected with univariate tests. A three-component PLS model linked MWF profiles to clinical phenotypes but no FA profiles. The three components appeared to follow along broad motor/nonmotor subtypes of "akinetic-rigid," "tremor-predominant," and "depression/apathy" subtypes, respectively. The first component showed associations between overall motor scores (r = -0.43, P = 0.0196) and cognitive performance (r = 0.44, P = 0.0171) with interhemispheric and long-range association fibers. A second component linked overall motor scores (r = -0.58, P = 0.0009) and tremor scores (r = -0.48, P = 0.0091) to predominantly projection fibers. The last component related depression (r = -0.60, P = 0.0006) and apathy scores (r = -0.66, P = 0.0001 and r = -49, P = 0.0072) to a mixture of association and projection fibers.
MWF was robustly linked to distinct clinical subtypes of PD and may serve as an additional tool to characterize the disease.
4 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;50:164-174.
白质（WM）的微观结构完整性对大脑的有效功能至关重要，许多神经退行性疾病都存在 WM 改变。
探讨帕金森病（PD）患者 WM 髓鞘的特点及其与临床特征的关系。
回顾性横断面研究。
共 29 例 PD 患者和 15 例健康对照者。
场强/序列：3T 扫描仪上采用多回波 GRASE 序列（回波间隔 10ms，EPI 扩散加权序列（b 值=700，梯度方向 32 个）。
比较两组之间 20 个感兴趣区（ROI）的髓鞘水分数（MWF）和各向异性分数（FA）。采用偏最小二乘法（PLS）将 MWF 和 FA 与临床和行为测量结果相关联。
组间比较采用两样本 t 检验。采用置换检验评估 PLS。Bootstrapping 用于检验成像特征的稳健性。
单变量检验未发现两组间髓鞘含量有差异。一个三成分 PLS 模型将 MWF 图谱与临床表型联系起来，但与 FA 图谱没有联系。这三个成分似乎分别沿着“无运动/僵硬型”、“震颤优势型”和“抑郁/淡漠型”的广泛运动/非运动亚型进行追踪。第一成分显示，总运动评分（r = -0.43，P = 0.0196）和认知表现（r = 0.44，P = 0.0171）与半球间和长程联合纤维之间存在相关性。第二成分将总运动评分（r = -0.58，P = 0.0009）和震颤评分（r = -0.48，P = 0.0091）与主要的投射纤维相关联。第三个成分将抑郁（r = -0.60，P = 0.0006）和淡漠评分（r = -0.66，P = 0.0001 和 r = -49，P = 0.0072）与联合纤维和投射纤维的混合物相关联。
MWF 与 PD 的不同临床亚型具有很好的相关性，可能成为该疾病特征的另一个辅助工具。
4 级
第 3 阶段
磁共振成像杂志 2019；50：164-174
