title: EEG and evoked potential findings in mitochondrial myopathies.
abstract: Electroencephalograms (EEGs) and evoked potentials (EPs) were studied in 43 patients with mitochondrial myopathies. Abnormalities were found most frequently in patients who presented predominantly or exclusively with central nervous system (CNS) dysfunction (abnormal EEGs in 18 of 21 patients, abnormal EPs in 9 of 11 patients). However, of patients presenting with ocular myopathy or proximal muscle weakness who had little or no CNS involvement clinically, 8 of 22 had abnormal EEGs and 5 of 10 had abnormal EPs, suggesting that electrophysiological tests are of value in demonstrating subclinical CNS disease in mitochondrial myopathy, although the abnormalities are not specific.
authors.affiliation: Department of Clinical Neurophysiology, National Hospital for Neurology and Neurosurgery, London, UK.
authors.forename: S J
authors.initials: SJ
authors.lastname: Smith
authors.forename: A E
authors.initials: AE
authors.lastname: Harding
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002493:Central Nervous System Diseases / Q000150:complications / Q000175:diagnosis*; D004569:Electroencephalography; D016057:Evoked Potentials, Auditory, Brain Stem; D005073:Evoked Potentials, Somatosensory; D005074:Evoked Potentials, Visual; D006801:Humans; D008875:Middle Aged; D017240:Mitochondrial Myopathies / Q000150:complications*