An Electrophysiological And Neuroimaging Study On Amyotrophic Lateral Sclerosis

A Study of Transcranial Magnetic Stimulation Motor Evoked Potentials on Amyotrophic Lateral SclerosisBackground:Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease affecting both lower and upper motor neurons (UMN). Clinical and subclinical lower motor neuron (LMN) impairment can be readily detected by regular electromyographies (EMG). However, there have been no objective indices to evaluate UMN lesions except clinical symptoms and signs. It is important to look for sensitive and objective UMN makers, because they can not only assist diagnosis and disease monitoring, but also help to screen early ALS patients into the clinical trials of emerging treatments and establish economical effect assessment indices. Transcranial magnetic stimulation motor evoked potentials (TMS-MEP) measurement is a neuroelectrophysiological method to assess conduction in central motor pathways. There have been highly inconsistent results in the reported TMS-MEP studies on ALS. Up to now, it is still a controversy whether it will become an effective marker to evaluate UMN involvement in ALS. Objective:To investigate the TMS-MEP changes in ALS and their correlations with clinical aspects. To assess the value of TMS-MEP in the diagnosis and UMN lesion evaluations of ALS. Methods:40 ALS patients complying with the revised El Escorial criteria, 8 patients with pure lower motor neuron (LMN) involvement and 34 age and sex matched healthy controls were enrolled in the study. TMS-MEP measurements were performed on bilateral abductor...