title: Repetitive nerve stimulation and single-fiber electromyography in the evaluation of patients with suspected myasthenia gravis or Lambert-Eaton myasthenic syndrome: Review of recent literature.
abstract: BACKGROUND
  Our aim in this study was to provide an updated literature review of electrodiagnostic testing in myasthenia gravis and Lambert-Eaton myasthenic syndrome.
  
  
  METHODS
  A systematic review of the recent literature was performed using the following key words: myasthenia gravis (MG); Lambert-Eaton myasthenic syndrome (LEMS); electromyography (EMG); repetitive nerve stimulation (RNS); single-fiber electromyography (SFEMG); nerve conduction study; and normative values.
  
  
  RESULTS
  Several articles supported testing of facial, bulbar, and respiratory muscles in the diagnosis of neuromuscular junction (NMJ) disorders, including muscle-specific kinase antibody (MuSK)-seropositive MG. Several articles supported use of concentric needle EMG as an alternative to SFEMG jitter in disorders of neuromuscular transmission. A limited number of articles addressed measurement of area (vs. amplitude) decrement in RNS and decreasing the threshold of post-exercise facilitation.
  
  
  CONCLUSIONS
  Electrodiagnostic testing continues to be useful for diagnosis of MG and LEMS, although the quality of the evidence is not great. This literature review summarizes RNS and jitter measurement of facial and respiratory muscles and use of concentric needle EMG for SFEMG.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Baylor College of Medicine, Houston, Texas, USA.
authors.forename: Faye Y
authors.initials: FY
authors.lastname: Chiou-Tan
authors.affiliation: Department of Neurology, Southern Illinois University School of Medicine, Springfield, Illinois, USA.
authors.forename: James M
authors.initials: JM
authors.lastname: Gilchrist
mesh_terms: D004558:Electric Stimulation / Q000379:methods; D004568:Electrodiagnosis / Q000379:methods*; D004576:Electromyography / Q000379:methods; D006801:Humans; D015624:Lambert-Eaton Myasthenic Syndrome / Q000175:diagnosis*; D009157:Myasthenia Gravis / Q000175:diagnosis*
keywords: Lambert-Eaton myasthenic syndrome; electromyography; myasthenia gravis; repetitive nerve stimulation; single-fiber electromyography