Imaging in Neuromuscular Disorders

Ultrasound and MRI are emerging valuable diagnostic tools in neuromuscular disorders. They can identify structural lesions in the nerve and surrounding tissues noninvasively, complementing the examination and electrodiagnostic testing in localization. Ultrasound can be particularly helpful when focal nerve lesions and entrapment are suspected but electrodiagnostic findings are nondiagnostic. Patterns of findings on nerve ultrasound can provide clues to their etiology, such as differentiating acquired and genetically caused demyelination, and assisting in the differentiation of multifocal motor neuropathy from motor neuron disease in selected cases. MRI can also be helpful in noninvasively identifying patterns of muscle involvement that suggest particular dystrophies.