Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892-1428, USA.
Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892-1428, USA; Chulalongkorn Center of Excellence for Parkinson's Disease & Related Disorders, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok 10330, Thailand.
Neuroimage Clin. 2022;36:103247. doi: 10.1016/j.nicl.2022.103247. Epub 2022 Oct 25.
Despite recent advances in tremor and dystonia classification, it remains difficult to discriminate essential tremor from dystonic tremor as they are similar in appearance and no biomarker exists. Further, tremor can appear in the same or a different body part than the dystonia. The aim of the current study was to better understand the differential pathophysiology of these tremors. We designed a cross-sectional case-control study and recruited 16 patients with essential tremor, 16 patients with dystonic tremor, and 17 age-matched healthy volunteers. We used multi-modal imaging combining resting-state functional MRI, diffusion tensor imaging, and magnetic resonance spectroscopy. We measured functional connectivity of resting-state fMRI to assess connectivity in the tremor network, fractional anisotropy and mean diffusivity with diffusion tensor imaging, and GABA+, Glutamate/Glutamine, Choline, and N-Acetylaspartate with spectroscopy (adjusted to Creatine). Our results showed reduced functional connectivity of resting-state fMRI between the cerebellum and dentate nucleus bilaterally for the essential tremor group, but not the dystonic tremor group, compared to healthy volunteers. There was higher fractional anisotropy in the middle cerebellar peduncle bilaterally for the dystonic tremor group compared to the essential tremor group as well as for essential tremor group compared to healthy volunteers. There was also higher fractional anisotropy in the red nucleus and corticospinal tract for essential tremor and dystonic tremor groups compared to healthy volunteers. We also showed reduced mean diffusivity in the cerebellum of both essential tremor and dystonic tremor groups compared to healthy volunteers. Finally, we found elevated GABA+/Cr in the cerebellum of the essential tremor and dystonic tremor groups compared to healthy volunteers, but no difference emerged between essential tremor and dystonic tremor groups. We did not find group differences in the other metabolites. Our results indicate cerebellar alterations in essential tremor and dystonic tremor patients compared to healthy volunteers, and further changes in the cerebellum network for the dystonic tremor patients. suggesting that the cerebellum is affected differently in both tremors.
尽管近年来在震颤和肌张力障碍分类方面取得了进展，但由于它们在外观上相似且没有生物标志物存在，因此仍然难以将特发性震颤与肌张力障碍性震颤区分开来。此外，震颤可能出现在与肌张力障碍相同或不同的身体部位。本研究旨在更好地了解这些震颤的差异病理生理学。我们设计了一项横断面病例对照研究，招募了 16 例特发性震颤患者、16 例肌张力障碍性震颤患者和 17 名年龄匹配的健康志愿者。我们使用多模态成像结合静息态功能磁共振成像、弥散张量成像和磁共振波谱。我们测量了静息态功能磁共振成像的功能连接，以评估震颤网络的连接，用弥散张量成像测量各向异性分数和平均弥散度，用波谱测量 GABA+、谷氨酸/谷氨酰胺、胆碱和 N-乙酰天门冬氨酸（调整为肌酸）。我们的结果显示，与健康志愿者相比，特发性震颤组双侧小脑和齿状核之间的静息态功能磁共振成像功能连接减少，但肌张力障碍性震颤组没有这种情况。与特发性震颤组和健康志愿者相比，肌张力障碍性震颤组双侧中脑小脑脚的各向异性分数较高。特发性震颤组和肌张力障碍性震颤组的红核和皮质脊髓束的各向异性分数也高于健康志愿者。我们还发现，与健康志愿者相比，特发性震颤组和肌张力障碍性震颤组的小脑平均弥散度降低。最后，我们发现特发性震颤组和肌张力障碍性震颤组的小脑 GABA+/Cr 升高，而健康志愿者没有这种情况，但特发性震颤组和肌张力障碍性震颤组之间没有差异。我们没有发现其他代谢物的组间差异。我们的结果表明，与健康志愿者相比，特发性震颤和肌张力障碍性震颤患者的小脑发生了改变，并且肌张力障碍性震颤患者的小脑网络发生了进一步的改变，这表明小脑在这两种震颤中受到的影响不同。
