Lin Po-Chieh, Chen Kai-Hsiang, Yang Bing-Shiang, Chen Yu-Jung
Department of Mechanical Engineering, National Chiao Tung University, 1001 University Road, Hsinchu City, 30010, Taiwan.
Neurology Division, National Taiwan University Hospital, Hsinchu Branch, Hsinchu City, 300, Taiwan.
BMC Neurol. 2018 Mar 9;18(1):25. doi: 10.1186/s12883-018-1027-2.
Spiral drawing on papers is a common tremor evaluation tool for diagnosing patients with essential tremor (ET) or Parkinson's disease (PD). No standard drawing methods and parameters that use graphic tablets are yet available for objective evaluation.
This study established a tremor assessment system for tremor severity by using graphic tablets. Twelve patients with ET and twelve patients with PD were tested to establish system algorithms, and six additional patients were tested with the developed system to evaluate its performance. The patients also performed spiral drawing with three guiding paradigms on a graphic tablet: traced along a given spiral (S1), performed freehand drawing (S2), and traced along a guiding point (S3). Three parameters were calculated to quantify tremor severity: the means of radial difference per radian (|dr/dθ|), the means of radial difference per second (|dr/dt|), and the area under curve (AUC) of the frequency spectrum of the velocity. Each patient's drawing was also evaluated using a visual rating scale (VRS) by experienced physicians. The interrater reliability was examined to identify the most consistent test paradigm.
The parameter |dr/dθ| and AUC correlated well with the VRS (R > 0.8) in S1, S2 and S3 tests. The S1 test presented the best interrater reliability (Weighted Kappa coefficient, k = 0.80) among three tests. The Weighted Kappa coefficients are 0.67 and 0.71 in S2 and S3 tests, respectively.
We developed three different guiding paradigms for spiral drawing on a digital graphic tablet for clinical tests. Three parameters were calculated to represent the tremor severity in spiral drawing and used to quantify temporal and spatial characteristics of tremor, and provided good correlation with current clinical assessments. The test "traced along a given spiral" is recommended due to its good interrater reliability.
在纸上画螺旋线是诊断特发性震颤（ET）或帕金森病（PD）患者的一种常见震颤评估工具。目前尚无使用数位绘图板的标准绘图方法和参数用于客观评估。
本研究利用数位绘图板建立了一种震颤严重程度评估系统。对12例ET患者和12例PD患者进行测试以建立系统算法，并对另外6例患者使用开发的系统进行测试以评估其性能。患者还在数位绘图板上采用三种引导范式进行螺旋线绘制：沿给定螺旋线追踪（S1）、徒手绘制（S2）以及沿引导点追踪（S3）。计算三个参数以量化震颤严重程度：每弧度的径向差值均值（|dr/dθ|）、每秒的径向差值均值（|dr/dt|）以及速度频谱的曲线下面积（AUC）。每位患者的绘图还由经验丰富的医生使用视觉评分量表（VRS）进行评估。检查评分者间信度以确定最一致的测试范式。
在S1、S2和S3测试中，参数|dr/dθ|和AUC与VRS的相关性良好（R > 0.8）。在三项测试中，S1测试的评分者间信度最佳（加权卡帕系数，k = 0.80）。S2和S3测试的加权卡帕系数分别为0.67和0.71。
我们为在数字绘图板上进行螺旋线绘制开发了三种不同的引导范式用于临床测试。计算了三个参数来表示螺旋线绘制中的震颤严重程度，并用于量化震颤的时间和空间特征，且与当前临床评估具有良好的相关性。由于其良好的评分者间信度，建议采用“沿给定螺旋线追踪”测试。
