Purpose of Review: This article reviews the roles of electrodiagnostic testing, imaging studies (MRI and ultrasound), and muscle biopsy in evaluating patients for possible muscle diseases.
Recent Findings: In addition to electrodiagnostic testing and muscle biopsy, muscle imaging is increasingly being used in the evaluation of patients with suspected muscle disease. MRI and ultrasound can help identify patterns of muscle involvement that may narrow the differential diagnosis and guide further testing. In addition, imaging can identify potential targets for muscle biopsy and can help evaluate for and exclude certain conditions that may mimic muscle disease.
Summary: This article provides a comprehensive overview of various testing modalities used in the evaluation of patients with suspected muscle disease, including electrodiagnostic studies, muscle imaging, and biopsy. In combination with a thorough history and clinical examination, these modalities can help narrow the differential diagnosis or, in certain cases, can confirm a specific etiology of muscle disease.
Address correspondence to Dr Laura K. Rosow, University of California, San Francisco, Department of Neurology, 400 Parnassus Ave, 8th floor, San Francisco, CA, 94143, firstname.lastname@example.org.
Relationship Disclosure: Dr Rosow reports no disclosure. Dr Amato has received personal compensation for serving on the medical advisory board of and as a consultant for Akashi Therapeutics, CSL Behring, and Novartis AG and for serving as associate editor of Muscle & Nerve and Neurology. Dr Amato has received research/grant support as site principal investigator for Alexion Pharmaceuticals, Inc; the National Institutes of Health; and Novartis AG; has received publishing royalties from UpToDate, Inc; and has provided expert witness testimony related to a wrongful diagnosis legal case.
Unlabeled Use of Products/Investigational Use Disclosure: Drs Rosow and Amato report no disclosures.
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