Tam Fred, Huang Yuexi, Schwartz Michael L, Schweizer Tom A, Hynynen Kullervo, Graham Simon J
Physical Sciences Platform, Sunnybrook Research Institute, Mailroom S604, 2075 Bayview Avenue, Toronto, ON, M4N 3M5, Canada.
Department of Surgery (Neurosurgery), Sunnybrook Health Sciences Centre, Toronto, Canada.
BMC Neurol. 2017 Apr 17;17(1):74. doi: 10.1186/s12883-017-0856-8.
Transcranial magnetic resonance guided focused ultrasound is an emerging technology under evaluation for treatment of essential tremor, a prevalent movement disorder. A qualitative evaluation is performed by a clinician periodically during the procedure to maximize treatment effects and minimize adverse effects. The present work demonstrates a magnetic resonance-compatible method to enable more precise, quantitative measurement of tremor severity.
Tremor severity was measured in 12 patients pre-, post-, and intra-operatively, using a magnetic resonance-compatible tablet and a computerized adaptation of drawing tasks from the widely-used Fahn-Tolosa-Marin Tremor Rating Scale. Tremor metrics based on spectral analysis were calculated for each drawing and compared using Wilcoxon signed rank tests.
Tremor metrics in the dominant (treated) hand were significantly and consistently lower post-operatively compared to pre-operatively, but there was no significant difference in the non-dominant (untreated) hand, as expected. Intra-operative metrics were intermediate between pre- and post-operative metrics.
Use of the tablet for quantitative tremor measurement was demonstrated pre-, post-, and intra-operatively during treatment of essential tremor, complementing standard qualitative assessment. With additional work, the system has potential to add objectivity to clinical trials and to aid treatment decision-making by providing a metric for optimization during the procedure, which may eventually lead to more optimal treatment. Enhancements and further studies are suggested, and extensions to fMRI studies of essential tremor and Parkinson's disease are also likely.
经颅磁共振引导聚焦超声是一种正在评估用于治疗特发性震颤（一种常见的运动障碍）的新兴技术。在治疗过程中，临床医生会定期进行定性评估，以最大化治疗效果并最小化不良反应。本研究展示了一种磁共振兼容的方法，能够更精确、定量地测量震颤严重程度。
使用磁共振兼容平板电脑和对广泛应用的法恩 - 托洛萨 - 马林震颤评定量表中的绘图任务进行计算机化改编，在12名患者的术前、术后及术中测量震颤严重程度。针对每张绘图计算基于频谱分析的震颤指标，并使用威尔科克森符号秩检验进行比较。
如预期的那样，与术前相比，优势（治疗）手的术后震颤指标显著且持续降低，但非优势（未治疗）手没有显著差异。术中指标介于术前和术后指标之间。
在特发性震颤治疗的术前、术后及术中均证明了使用平板电脑进行震颤定量测量，这对标准定性评估起到了补充作用。通过进一步研究，该系统有可能为临床试验增加客观性，并通过在治疗过程中提供优化指标来辅助治疗决策，最终可能带来更优化的治疗效果。建议进行改进和进一步研究，并且该技术也可能扩展到对特发性震颤和帕金森病的功能磁共振成像研究中。
