Sonoo Masahiro
Department of Neurology, Teikyo University School of Medicine, Kaga 2-11-1, Itabashi-ku, Tokyo 173-8605, Japan.
Muscle Nerve Suppl. 2002;11:S98-S102. doi: 10.1002/mus.10154.
Quantitative motor unit potential (MUP) analysis, which is a leading method of quantitative evaluation of concentric needle electromyography, has several inherent limitations. First, the most essential features of neurogenic or myogenic changes manifest as recruitment abnormalities, rather than as changes in MUP morphology. Second, two factors related to MUP sampling, focusing and level of contraction, greatly influence the parameters of sampled MUPs. Third, the MUP duration, considered to be the cardinal parameter in MUP analysis, has several drawbacks, including low stability and low discriminant sensitivity. We developed a new MUP parameter, the size index (SI), which is calculated from the MUP amplitude and area/amplitude ratio (thickness). The SI remained almost constant during electrode movements, as demonstrated by manual scanning of MUPs. It is a stable and robust parameter and achieved an extremely high ability to discriminate between normal and large neurogenic MUPs. It identifies features related to the sound produced by the MUP on the audio monitor, which is often used by trained electromyographers for qualitative assessments of MUPs.
定量运动单位电位（MUP）分析是同心针肌电图定量评估的主要方法，但存在一些固有局限性。首先，神经源性或肌源性改变的最基本特征表现为募集异常，而非MUP形态改变。其次，与MUP采样、聚焦和收缩水平相关的两个因素对采样MUP的参数有很大影响。第三，被认为是MUP分析核心参数的MUP时限存在几个缺点，包括稳定性低和判别敏感性低。我们开发了一种新的MUP参数——大小指数（SI），它由MUP振幅和面积/振幅比（厚度）计算得出。如手动扫描MUP所示，SI在电极移动过程中几乎保持不变。它是一个稳定且可靠的参数，在区分正常和大型神经源性MUP方面具有极高的能力。它识别与音频监测器上MUP产生的声音相关的特征，训练有素的肌电图师经常使用该声音对MUP进行定性评估。
