Southeast Parkinson's Disease Research, Education, and Clinical Center (PADRECC), Hunter-Holmes McGuire Veterans Affairs Medical Center, Richmond, VA, USA; Virginia Commonwealth University, Department of Biomedical Engineering, Richmond, VA, USA.
Virginia Commonwealth University, Department of Biomedical Engineering, Richmond, VA, USA.
Parkinsonism Relat Disord. 2014 Jul;20(7):743-7. doi: 10.1016/j.parkreldis.2014.03.028. Epub 2014 Apr 8.
Our recent report of ocular tremor in Parkinson's disease (PD) has raised considerable controversy as to the origin of the tremor. Using an infrared based eye tracker and a magnetic head tracker, we reported that ocular tremor was recordable in PD subjects with no apparent head tremor. However, other investigators suggest that the ocular tremor may represent either transmitted appendicular tremor or subclinical head tremor inducing the vestibulo-ocular reflex (VOR). The present study aimed to further investigate the origin of ocular tremor in PD.
Eye movements were recorded in 8 PD subjects both head free, and with full head restraint by means of a head holding device and a dental impression bite plate. Head movements were recorded independently using both a high sensitivity tri-axial accelerometer and a magnetic tracking system, each synchronized to the eye tracker.
Ocular tremor was observed in all 8 PD subjects and was not influenced by head free and head fixed conditions. Both magnetic tracking and accelerometer recordings supported that the ocular tremor was fully independent of head position.
The present study findings support our initial findings that ocular tremor is a fundamental feature of PD unrelated to head movements. Although the utility of ocular tremor for diagnostic purposes requires validation, current findings in large cohorts of PD subjects suggest its potential as a reliable clinical biomarker.
我们最近关于帕金森病（PD）眼震的报告引起了相当大的争议，即震颤的起源。我们使用基于红外的眼动追踪器和磁头追踪器报告说，在没有明显头部震颤的 PD 患者中可以记录到眼震。然而，其他研究人员认为，眼震可能代表传递的附属震颤或亚临床头部震颤引起的前庭眼反射（VOR）。本研究旨在进一步探讨 PD 中眼震的起源。
通过头部固定装置和牙印咬板，在 8 名 PD 患者中记录眼动，分别在无头部固定和完全头部固定条件下进行。使用三轴高灵敏度加速度计和磁跟踪系统分别独立记录头部运动，每个系统都与眼动追踪器同步。
所有 8 名 PD 患者均观察到眼震，不受无头部固定和头部固定条件的影响。磁跟踪和加速度计记录均支持眼震完全独立于头部位置。
本研究结果支持我们的初步发现，即眼震是 PD 的一个基本特征，与头部运动无关。尽管眼震在诊断中的用途需要验证，但目前在大量 PD 患者中的研究结果表明，它具有作为可靠临床生物标志物的潜力。
