title: Videonystagmography to assess blinking.
abstract: BACKGROUND
  In order to measure blinking, we developed a dynamic device consisting of a CCD camera connected to a videonystagmography machine. We developed an artificial pupil that allowed the camera to track movements of the upper eyelid.
  
  
  METHODS
  Blinking parameters were measured in eight healthy volunteers, studying spontaneous blinking (SB) and voluntary blinking (VB) responses. Closing time, opening time, closing speed, vertical amplitude, horizontal amplitude and frequency of spontaneous blinking were recorded.
  
  
  RESULTS
  In SB, opening time (0.21 +/- 0.04 s) was significantly longer than closing time (0.10 +/- 0.02 s) (p < 0.0001). Mean closing speed was 87 +/- 26 m/s in SB and 168 +/- 59 m/s in VB. Mean vertical amplitude was 9.1 +/- 2.2 mm. Mean vertical amplitude was lower in SB (9.1 +/- 2.2 mm) than in VB (12.3 +/- 1.9 mm) (p < 0.001). Mean horizontal amplitude was also lower in SB (2.7 +/- 0.9 mm) than in VB (3.8 +/- 0.9 mm) (p < 0.05). Frequency of SB was 18.4 +/- 3.4 per minute.
  
  
  CONCLUSIONS
  Computer-assisted video acquisition provides real-time measurement of eyeblink dynamics. On healthy volunteers, this method enables accurate measurement of opening and closing responses as well as associated horizontal movement, and enables differentiating spontaneous and voluntary blinking.
authors.affiliation: Department of Ophthalmology, CHU Dupuytren, 2 Av Martin Luther King, 87042 Limoges Cedex, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Casse
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Sauvage
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Adenis
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Robert
mesh_terms: D000328:Adult; D001767:Blinking / Q000502:physiology*; D053483:Eye Movement Measurements; D005143:Eyelids / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009760:Nystagmus, Physiologic / Q000502:physiology*; D014741:Video Recording