[Muscle ultrasonography: a new diagnostic tool for the diagnosis of ALS]

The diagnosis of amyotrophic lateral sclerosis (ALS) is frequently challenging, and needle EMG plays a central role to assess lower motor neuron dysfunction. Ultrasonography can clearly visualize fasciculation, one of characteristic features of ALS, and could contribute to the diagnosis of ALS. Echogenicity might be useful to assess chronic denervated changes of muscles, although there are some issues to be solved with regard to establishing methods and normal values. Attempts to utilize ultrasound to diagnose ALS have been just started. However, ultrasound has an advantage of non-invasiveness over EMG or nerve conduction study. Ultrasound could become a new tool to evaluate neuromuscular disease without pain in the near future.