Neuromuscular Diseases Unit/ALS Clinic, Kantonsspital St. Gallen, St. Gallen, Switzerland.
Neuromuscular Diseases Unit/ALS Clinic, Kantonsspital St. Gallen, St. Gallen, Switzerland.
Clin Neurophysiol. 2018 Aug;129(8):1756-1762. doi: 10.1016/j.clinph.2018.04.614. Epub 2018 May 3.
Motor Unit Number Index (MUNIX) is a quantitative neurophysiological method that reflects loss of motor neurons in Amyotrophic Lateral Sclerosis (ALS) in longitudinal studies. It has been utilized in one natural history ALS study and one drug trial (Biogen USA) after training and qualification of raters.
Prior to testing patients, evaluators had to submit test-retest data of 4 healthy volunteers. Twenty-seven centres with 36 raters measured MUNIX in 4 sets of 6 different muscles twice. Coefficient of variation of all measurements had to be <20% to pass the qualification process. MUNIX COV of the first attempt, number of repeated measurements and muscle specific COV were evaluated.
COV varied considerably between raters. Mean COV of all raters at the first measurements was 12.9% ± 13.5 (median 8.7%). Need of repetitions ranged from 0 to 43 (mean 10.7 ± 9.1, median 8). Biceps and first dorsal interosseus muscles showed highest repetition rates. MUNIX variability correlated considerably with variability of compound muscle action potential.
MUNIX revealed generally good reliability, but was rater dependent and ongoing support for raters was needed.
MUNIX can be implemented in large clinical trials as an outcome measure after training and a qualification process.
运动单位数量指数（MUNIX）是一种定量神经生理学方法，可反映肌萎缩侧索硬化症（ALS）中运动神经元的丧失。在经过培训和资格认证的评估者的帮助下，它已被用于一项自然病史 ALS 研究和一项药物试验（美国百健）中。
在测试患者之前，评估者必须提交 4 名健康志愿者的测试-再测试数据。27 个中心的 36 名评估者对 4 组 6 个不同的肌肉进行了两次 MUNIX 测量。所有测量的变异系数（CV）必须<20%，才能通过资格认证过程。评估了第一次尝试的 MUNIX CV、重复测量次数和肌肉特异性 CV。
评估者之间的 CV 差异很大。所有评估者第一次测量的平均 CV 为 12.9%±13.5（中位数 8.7%）。重复次数的范围从 0 到 43（平均值 10.7±9.1，中位数 8）。二头肌和第一背侧骨间肌的重复测量率最高。MUNIX 的变异性与复合肌肉动作电位的变异性密切相关。
MUNIX 总体上显示出良好的可靠性，但依赖于评估者，需要对评估者进行持续支持。
MUNIX 可以在大型临床试验中作为培训和资格认证过程后的一种结局测量指标实施。
