title: Utility of laryngeal electromyography in predicting recovery after vocal fold paralysis.
abstract: OBJECTIVE
  To determine the value of laryngeal electromyography in predicting recovery after vocal fold paralysis and to determine what elements of laryngeal electromyography are most predictive of outcome.
  
  
  METHODS
  Cohort study with retrospective data review.
  
  
  METHODS
  University voice center.
  
  
  METHODS
  Consecutive sample of 31 patients with vocal fold paralysis diagnosed by indirect laryngoscopy, using either nasal insertion with a flexible nasopharyngoscope or peroral with a 70 degrees Hopkins rod. Inclusion criteria were that laryngeal electromyography had to have been performed between 21 days and 6 months from the onset of symptoms and patients must have been followed a minimum of 6 months.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Vocal fold motion at 6 months from onset of symptoms.
  
  
  RESULTS
  Nine subjects (29%) had resolved vocal fold motion, whereas 22 (71%) had persistent vocal fold paralysis. By using our laryngeal electromyography paradigm, 4 of 6 patients with a laryngeal electromyography prognosis of excellent resolved. The predictive value for a negative test was 66.7%. For patients with a fair or poor prognosis, 5 of 25 resolved. The predictive value for a positive test was 80%. Only 8 of 22 patients with persistent vocal fold paralysis had fibrillations, and spontaneous activity was not significantly related to outcome. Patients with absent or greatly decreased motor unit recruitment had a significantly higher proportion of permanent vocal fold paralysis (P<.05). Stepwise forward logistic regression determined that prognosis by laryngeal electromyography and onset time were significant predictors of outcome (P<.01). The model predicted 44.4% of resolved cases, which represents a moderate prediction.
  
  
  CONCLUSIONS
  This study confirms the utility of laryngeal electromyography in assessing prognosis for recovery of vocal fold motion after laryngeal nerve injury. The results support our hypothesis that preset decision rules based on laryngeal electromyography data can be effectively used to determine a prognosis for recovery of vocal fold motion.
authors.affiliation: Department of Physical Medicine and Rehabilitation, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA. Muninmc@msx.upmc.edu
authors.forename: Michael C
authors.initials: MC
authors.lastname: Munin
authors.forename: Clark A
authors.initials: CA
authors.lastname: Rosen
authors.forename: Thomas
authors.initials: T
authors.lastname: Zullo
mesh_terms: D004576:Electromyography; D006801:Humans; D007830:Larynx / Q000503:physiopathology*; D016015:Logistic Models; D008875:Middle Aged; D009046:Motor Neurons / Q000502:physiology; D015999:Multivariate Analysis; D009119:Muscle Contraction / Q000502:physiology; D009126:Muscle Relaxation / Q000502:physiology; D011237:Predictive Value of Tests; D011379:Prognosis; D020127:Recovery of Function; D011999:Recruitment, Neurophysiological / Q000502:physiology; D012009:Recurrent Laryngeal Nerve / Q000503:physiopathology; D012189:Retrospective Studies; D014826:Vocal Cord Paralysis / Q000503:physiopathology / Q000534:rehabilitation*