Chulalongkorn Center of Excellence on Parkinson Disease & Related Disorders, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
Chulalongkorn Center of Excellence on Parkinson Disease & Related Disorders, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand.
J Parkinsons Dis. 2014;4(2):273-82. doi: 10.3233/JPD-130311.
Tremors are common clinical complaints among the elderly and non-specialist physicians frequently are challenged by the need to provide an accurate diagnosis of various tremor syndromes, particularly Parkinson's disease and essential tremor in their busy practices.
We sought to develop an easy-to-use, mobile robust, accurate, and cost-effective instrument that can objectively quantify tremors.
The low-cost, 3-dimension, inertial sensors were developed for automated tremor assessment. The main sensor unit consists of a 3-axis accelerometer and a 3-axis gyroscope for the purpose of measuring the tilting angle relative to the gravity, linear acceleration, and angular velocity of the body segments affected by tremors. The transmitter consists of five main modules, including a microcontroller, power management module, sensor module, external memory interface module, and Bluetooth™ communication interface module, which connects to the sensors by a thin wire. The signal processing utilized fast Fourier transform analysis to include RMS angular rate, RMS angle, RMS rate, RMS velocity, peak frequency, peak frequency magnitude, and dispersion of frequency as variables.
The prototype was tested with a tremor simulator at programmable angular rates of 2-, 4-, and 8-Hz confirming its accuracy. Twenty subjects (10 PD and 10 age-matched ET patients) participated as part of the experimental verification to perform three tremor tasks, including rest, postural, and kinetic tremor according to the teaching videotape of the motor section of the UPDRS. The mean peak frequency was significantly lower in PD than ET patients at rest on the x- (p < 0.01) and z-axis (p < 0.01). In PD patients, the RMS angular rate, RMS angle, RMS rate, RMS velocity, and peak magnitude were all significantly higher than those values in ET patient at rest while the data was not significantly difference during postural and kinetic actions. ET patients had significantly higher peak frequency during postural action in the y-axis than PD patients (p < 0.05).
The study provides the technical development of an accurate, inexpensive, and simple method to measure the kinematics of tremor in humans. Further studies are warranted to confirm the validity of each parameter and the diagnostic accuracy in each tremor syndrome.
震颤是老年人常见的临床主诉，非专科医生在繁忙的临床实践中经常需要准确诊断各种震颤综合征，特别是帕金森病和特发性震颤。
我们旨在开发一种易于使用、移动性强、准确且经济高效的仪器，以客观地量化震颤。
开发了低成本的 3 维惯性传感器，用于自动震颤评估。主传感器单元由 3 轴加速度计和 3 轴陀螺仪组成，用于测量相对于重力的倾斜角度、身体受震颤影响的部位的线性加速度和角速度。发射器由五个主要模块组成，包括微控制器、电源管理模块、传感器模块、外部存储接口模块和蓝牙™通信接口模块，通过细电线与传感器连接。信号处理利用快速傅里叶变换分析，包括 RMS 角速率、RMS 角度、RMS 速率、RMS 速度、峰值频率、峰值频率幅度和频率离散度作为变量。
在可编程角速度为 2、4 和 8 Hz 的震颤模拟器上对原型进行了测试，以确认其准确性。20 名受试者（10 名帕金森病患者和 10 名年龄匹配的特发性震颤患者）作为实验验证的一部分，根据 UPDRS 运动部分的教学录像，进行了 3 项震颤任务，包括休息、姿势和动力性震颤。在休息时，PD 患者的 x 轴（p < 0.01）和 z 轴（p < 0.01）的平均峰值频率明显低于 ET 患者。在 PD 患者中，休息时 RMS 角速率、RMS 角度、RMS 速率、RMS 速度和峰值幅度均明显高于 ET 患者，而在姿势和动力动作时数据无显著差异。在姿势动作时，ET 患者的 y 轴的峰值频率明显高于 PD 患者（p < 0.05）。
本研究提供了一种准确、廉价且简单的测量人体震颤运动学的方法的技术开发。需要进一步的研究来确认每个参数的有效性和每个震颤综合征的诊断准确性。
