title: A prospective study assessing the utility of Cogan's lid twitch sign in patients with isolated unilateral or bilateral ptosis.
abstract: OBJECTIVE
  Cogan's lid twitch is thought to suggest myasthenia gravis in patients with unexplained ptosis. The validity of this clinical test has not been established. We conducted a prospective study to ascertain the sensitivity and specificity of this finding.
  
  
  METHODS
  35 patients with isolated, symptomatic ptosis, referred to a neuro-ophthalmologist or oculoplastics specialist were enrolled. The presence or absence of Cogan's lid twitch was noted, according to standard technique. Further testing was performed, and the final diagnosis for each patient was recorded.
  
  
  RESULTS
  Four patients were found to have a Cogan's lid twitch. Two patients had ocular myasthenia gravis as the final diagnosis, and of those, only one had a twitch.
  
  
  CONCLUSIONS
  The sensitivity and specificity of Cogan's lid twitch is relatively low. Other conditions may cause a lid twitch as well. The presence of a Cogan's lid twitch may increase suspicion of myasthenia, but is not diagnostic, and does not exclude alternate etiologies of ptosis.
authors: Ophthalmology and Neurology, Kresge Eye Institute/Wayne State University, Detroit, MI 48201, USA. gvanstaver@med.wayne.edu
authors: Gregory P
authors: GP
authors: Van Stavern
authors: Aash
authors: A
authors: Bhatt
authors: James
authors: J
authors: Haviland
authors: Evan H
authors: EH
authors: Black
mesh_terms: D001763:Blepharoptosis / Q000175:diagnosis* / Q000503:physiopathology*; D005141:Eyelid Diseases / Q000209:etiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D009157:Myasthenia Gravis / Q000150:complications; D011446:Prospective Studies; D012680:Sensitivity and Specificity