Medical Scientist Training Program, University of Rochester, Rochester, New York, USA.
Department of Neurology, Washington University in Saint Louis, Saint Louis, Missouri, USA.
Mov Disord. 2018 Mar;33(3):449-458. doi: 10.1002/mds.27298. Epub 2018 Feb 20.
Focal embouchure dystonia impairs orofacial motor control in wind musicians and causes professional disability. A paucity of quantitative measures or rating scales impedes the objective assessment of treatment efficacy.
We quantified specific features of focal embouchure dystonia using acoustic measures and developed a metric to assess severity across multiple domains of symptomatic impairment.
We recruited 9 brass musicians with and 6 without embouchure dystonia. The following 4 domains of symptomatic dysfunction in focal embouchure dystonia were identified: pitch inaccuracy, sound instability and tremor, sound breaks, and timing variability. Musicians performed sustained tones and sequences, and then acoustic variables within each domain were quantified. A composite brass acoustic severity score composed of these variables was validated against clinical global impressions of severity.
Musicians with dystonia performed worse in acoustic domains of pitch inaccuracy (median: dystonia = 100%, control = 62%), instability (median shimmer: dystonia = 3%, control = 2%), and breaks (median: dystonia = 0.34%, control = 0.05%). Tremor in embouchure dystonia was 5 to 8 Hz, intermittent, and variable in amplitude. Rhythmic variability did not differ between groups. Participants with embouchure dystonia had different patterns of impairment across variables. Composite severity scores strongly predicted clinical global impression of severity (R = 0.95).
Acoustic variables distinguish musicians with embouchure dystonia from controls and reflect different types of symptomatic impairments. Our composite acoustic severity score predicts severity of clinical global impression for musicians with different patterns of symptomatic impairment and may provide a foundation for developing a clinical rating scale. © 2018 International Parkinson and Movement Disorder Society.
焦点口周肌张力障碍会损害管乐器吹奏者的口面运动控制能力，并导致职业障碍。缺乏定量测量或评分量表会妨碍对治疗效果的客观评估。
我们使用声学测量来量化焦点口周肌张力障碍的特定特征，并开发了一种评估多个症状损伤领域严重程度的度量标准。
我们招募了 9 名患有口周肌张力障碍的铜管乐器演奏者和 6 名没有口周肌张力障碍的演奏者。确定了焦点口周肌张力障碍的 4 个症状损伤领域：音高不准确、声音不稳定和震颤、声音中断以及时程变化。演奏者演奏持续音和音序，然后对每个领域的声学变量进行量化。由这些变量组成的复合铜管乐器声学严重程度评分与临床总体印象严重程度评分进行了验证。
患有肌张力障碍的演奏者在音高不准确（中位数：肌张力障碍=100%，对照组=62%）、不稳定（中位数：颤抖=3%，对照组=2%）和中断（中位数：肌张力障碍=0.34%，对照组=0.05%）等声学领域的表现更差。口周肌张力障碍中的震颤为 5 至 8 Hz，间歇性且幅度可变。节奏变化在两组之间没有差异。患有口周肌张力障碍的参与者在各个变量之间存在不同的损伤模式。复合严重程度评分与临床总体印象严重程度评分高度相关（R=0.95）。
声学变量可区分患有口周肌张力障碍的演奏者和对照组，并反映不同类型的症状损伤。我们的复合声学严重程度评分可预测具有不同症状损伤模式的演奏者的临床总体印象严重程度，并可能为开发临床评分量表提供基础。
