Novel approaches to assessing upper motor neuron dysfunction in motor neuron disease/amyotrophic lateral sclerosis: IFCN handbook chapter

作者：Thanuja Dharmadasa, Nathan Pavey, Sicong Tu, Parvathi Menon, William Huynh, Colin Mahoney, Hannah C. Timmins, Mana Higashihara, Mehdi van den Bos, Kazumoto Shibuya, Satoshi Kuwabara, Julian Großkreutz, Matthew C. Kiernan, Steve Vucic · 发表于：Clinical Neurophysiology · 年份：2024 · DOI：10.1016/j.clinph.2024.04.010 · 被引用次数：20 · 研究领域：Transcranial Magnetic Stimulation Studies、Amyotrophic Lateral Sclerosis Research、Muscle activation and electromyography studies

Identifying upper motor neuron (UMN) dysfunction is fundamental to the diagnosis and understanding of disease pathogenesis in motor neuron disease (MND). The clinical assessment of UMN dysfunction may be difficult, particularly in the setting of severe muscle weakness. From a physiological perspective, transcranial magnetic stimulation (TMS) techniques provide objective biomarkers of UMN dysfunction in MND and may also be useful to interrogate cortical and network function. Single, paired- and triple pulse TMS techniques have yielded novel diagnostic and prognostic biomarkers in MND, and have provided important pathogenic insights, particularly pertaining to site of disease onset. Cortical hyperexcitability, as heralded by reduced short interval intracortical inhibition (SICI) and increased short interval intracortical facilitation, has been associated with the onset of lower motor neuron degeneration, along with patterns of disease spread, development of specific clinical features such as the split hand phenomenon, and may provide an indication about the rate of disease progression. Additionally, reduction of SICI has emerged as a potential diagnostic aid in MND. The triple stimulation technique (TST) was shown to enhance the diagnostic utility of conventional TMS measures in detecting UMN dysfunction in MND. Separately, sophisticated brain imaging techniques have uncovered novel biomarkers of neurodegeneration that have bene associated with progression. The present review w...