Dyke Jonathan P, Cameron Eric, Hernandez Nora, Dydak Ulrike, Louis Elan D
Department of Radiology, Citigroup Biomedical Imaging Center, Weill Cornell Medicine, New York, NY USA.
School of Health Sciences, Purdue University, West Lafayette, IN USA.
Cerebellum Ataxias. 2017 Jul 3;4:10. doi: 10.1186/s40673-017-0069-3. eCollection 2017.
The pathophysiological basis for essential tremor (ET) remains unclear, although evidence increasingly links it to a disordered and perhaps degenerative cerebellum. Prior imaging studies have treated the cerebellum Our hypothesis was that regional differences in cerebellar gray matter (GM) density may better distinguish ET cases from controls. Forty-seven ET cases and 36 control subjects were imaged using magnetic resonance imaging (MRI). The cerebellum was segmented into 34 lobes using a Spatially Unbiased Infra-Tentorial Template (SUIT) atlas within the Statistical Parametric Mapping (SPM) analysis package. Age, gender and Montreal Cognitive Assessment (MoCA) scores were regressed out from the statistical models to isolate group effects. ET cases were further stratified into phenotypically-defined subgroups. The Benjamini-Hochberg False Discovery Rate procedure (BH FDR) (α = 0.1) was used to correct for multiple comparisons.
When all ET cases and controls were compared, none of the regions met the BH FDR criteria for significance. When compared with controls, ET cases with head or jaw tremor ( = 27) had significant changes in GM density in nine cerebellar lobules, with a majority in the left cerebellar region, and each meeting the BH FDR criteria. Likewise, ET cases with voice tremor ( = 22) exhibited significant changes in 11 lobules in both left and right regions and the vermis. These analyses, in sum, indicated decreases in GM density in lobules I-IV, V, VI, VII and VIII as well as the vermis. ET cases with severe tremor ( = 20) did not show regions of change that survived the BH FDR procedure when compared to controls.
We showed that ET cases with various forms of cranial tremor differed from controls with respect to cerebellar GM density, with evidence of GM reduction across multiple cerebellar regions. Additional work, using a lobule-by-lobule approach, is needed to confirm these results and precisely map the regional differences in ET cases, subgroups of ET cases, and controls.
尽管越来越多的证据表明特发性震颤（ET）与小脑功能紊乱甚至可能是退行性变有关，但其病理生理基础仍不清楚。先前的影像学研究对小脑进行了……我们的假设是，小脑灰质（GM）密度的区域差异可能能更好地将ET病例与对照区分开来。对47例ET病例和36名对照者进行了磁共振成像（MRI）检查。在统计参数映射（SPM）分析软件包中，使用空间无偏幕下模板（SUIT）图谱将小脑分割为34个叶。年龄、性别和蒙特利尔认知评估（MoCA）得分从统计模型中剔除，以分离组间效应。ET病例进一步分层为表型定义的亚组。采用Benjamini-Hochberg错误发现率程序（BH FDR）（α = 0.1）对多重比较进行校正。
当比较所有ET病例和对照时，没有区域达到BH FDR显著性标准。与对照相比，有头部或下颌震颤的ET病例（n = 27）在9个小脑叶的GM密度有显著变化，大多数在左侧小脑区域，且每个区域均达到BH FDR标准。同样，有语音震颤的ET病例（n = 22）在左右区域及蚓部的11个叶中表现出显著变化。总之，这些分析表明I-IV、V、VI、VII和VIII叶以及蚓部的GM密度降低。与对照相比，重度震颤的ET病例（n = 20）在BH FDR程序后未显示出有变化的区域。
我们发现，不同形式的头部震颤的ET病例在小脑GM密度方面与对照不同，多个小脑区域有GM减少的证据。需要采用逐个叶的方法进行更多研究，以证实这些结果，并精确描绘ET病例及其亚组与对照之间的区域差异。
