Abstract:
Essential tremor (ET) is the most prevalent movement disorder with poorly understood etiology. Some neuroimaging studies report cerebellar involvement whereas others do not. This discrepancy may stem from underpowered studies, differences in statistical modeling or variation in magnetic resonance imaging (MRI) acquisition and processing. To resolve this, we investigated the cerebellar structural differences using a local advanced ET dataset augmented by matched controls from PPMI and ADNI. We tested the hypothesis of cerebellar involvement using three neuroimaging biomarkers: VBM, gray/white matter volumetry and lobular volumetry. Furthermore, we assessed the impacts of statistical models and segmentation pipelines on results. Results indicate that the detected cerebellar structural changes vary with methodology. Significant reduction of right cerebellar gray matter and increase of the left cerebellar white matter were the only two biomarkers consistently identified by multiple methods. Results also show substantial volumetric overestimation from SUIT-based segmentation-partially explaining previous literature discrepancies. This study suggests that current estimation of cerebellar involvement in ET may be overemphasized in MRI studies and highlights the importance of methods sensitivity analysis on results interpretation. ET datasets with large sample size and replication studies are required to improve our understanding of regional specificity of cerebellum involvement in ET. PROTOCOL REGISTRATION: The stage 1 protocol for this Registered Report was accepted in principle on 21 March 2022. The protocol, as accepted by the journal, can be found at: https://doi.org/10.6084/m9.figshare.19697776 .
摘要:
原发性震颤(ET)是最常见的运动障碍,病因知之甚少。一些神经影像学研究报告小脑受累,而另一些则没有。这种差异可能源于动力不足的研究,磁共振成像(MRI)采集和处理中统计建模或变异的差异。为了解决这个问题,我们使用由PPMI和ADNI的匹配对照增强的局部高级ET数据集,调查了小脑结构差异.我们使用三种神经影像学生物标志物测试了小脑受累的假设:VBM,灰质/白质容积和小叶容积。此外,我们评估了统计模型和细分管道对结果的影响.结果表明,检测到的小脑结构变化随方法而异。右侧小脑灰质的显著减少和左侧小脑白质的增加是通过多种方法一致鉴定的仅有的两种生物标志物。结果还显示出基于SUIT的分割的大量体积高估-部分解释了以前的文献差异。这项研究表明,在MRI研究中可能过分强调了小脑参与ET的当前估计,并强调了方法敏感性分析对结果解释的重要性。需要具有大样本量和复制研究的ET数据集,以提高我们对小脑参与ET的区域特异性的理解。协议注册:本注册报告的第一阶段协议于2022年3月21日原则上被接受。协议,被杂志接受,可以找到:https://doi.org/10.6084/m9。图19697776。