TMS Evaluation in Motor Neuron Diseases

In patients with ALS, certain TMS measures appear abnormal and decline over time, but the technique is not yet appropriate for routine analysis of individual patients.

In patients with amyotrophic lateral sclerosis (ALS), electromyography reliably identifies lower motor neuron dysfunction, but diagnosing and quantifying the upper motor neuron (UMN) dysfunction remain difficult. Transcranial magnetic stimulation (TMS) methods have been tested, but the results have been inconsistent. To provide additional longitudinal data, researchers evaluated 60 patients diagnosed with various forms of motor neuron disease (including 46 with ALS) every 3 months for up to six visits, and compared the results to those in a normal population (controls). TMS measures included resting motor threshold to the abductor digiti minimi (ADM) muscle, central motor conduction time (CMCT) to ADM and tibialis anterior (TA) muscle bilat…

Reviewing Author

Mark Hallett, MD