Clinical electrophysiology of the upper and lower motor neuron in amyotrophic lateral sclerosis
Clinical electrophysiology of the upper and lower motor neuron in amyotrophic lateral sclerosis
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DOI：
10.1055/s-2001-15261
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发表时间：
2001-01-01
影响因子：
2.7
通讯作者：
Eisen, A
中科院分区：
文献类型：
--
作者：
Eisen, A
电生理学在肌萎缩侧索硬化症（ALS）中很重要。它有助于评估疾病的严重程度和进展速度，并在评估治疗试验的疗效方面发挥作用。目前，电生理学是确认疑似ALS的唯一方法，并且已将其纳入埃尔埃斯科里亚标准。针式肌电图可识别临床上“未受影响的肌肉”（包括延髓肌肉组织）中的疾病，确认前角细胞受累，并可检测呼吸肌（肋间肌和膈肌）的早期受累。传导研究是必要的，以排除运动神经病与多灶性传导阻滞。采用经颅磁刺激的各种技术（皮质阈值、皮质沉默期、双刺激）已经证明ALS中的运动皮质是过度兴奋的。中枢运动传导在ALS中是正常的，但在D90A SOD1突变中是唯一缓慢的。使用刺激周时间直方图（PSTH），可以估计单一兴奋性突触后电位（EPSP）的大小。在ALS中，EPSP通常是去分化的。随着时间的推移，它变得在幅度上减小，并且慢传导分量在PSTH的主峰中变得可识别。这反映了通过慢运动通路的传导。在肯尼迪病中未观察到PSTH的消失，这意味着ALS中观察到的变化是由于脊髓上机制。
Electrophysiology is important in amyotrophic lateral sclerosis (ALS). It helps in the assessment of disease severity and rate of progression, and it plays a role in evaluating the efficacy of therapeutic trials. Presently, electrophysiology is the only means of confirming suspected ALS, and this has been incorporated into the El Escorial criteria. Needle electromyography identifies disease in clinically "unaffected muscles" including bulbar musculature, confirms involvement of anterior horn cells, and can detect early involvement of respiratory muscles (intercostals and diaphragm). Conduction studies are imperative to rule out motor neuropathy with multifocal conduction block. Various techniques (cortical threshold, cortical silent period, double stimulation) employing transcranial magnetic stimulation have demonstrated that the motor cortex in ALS is hyperexcitable. Central motor conduction is normal in ALS but uniquely slow in the D90A SOD1 mutation. Using peristimulus time histograms (PSTHs) it is possible to estimate the size of a unitary excitatory postsynaptic potential (EPSP). In ALS the EPSP is typically desynchronized. With time it becomes reduced in amplitude and a slow conducting component becomes recognizable in the primary peak of the PSTH. This reflects conduction through a slow motor pathway. Abnormalities of the PSTH are not seen in Kennedy's disease, implying that the changes seen in ALS are due to supraspinal mechanisms.