title: [Variance of retinal vessel diameter response to flicker light. A methodical clinical study].
abstract: OBJECTIVE
  The study investigated the variance of the retinal vessel response to flicker light between the right and left eyes and after a short and a medium-length time interval.
  
  
  METHODS
  The prospective study included 28 volunteers. In the first exam both eyes were examined. One eye selected randomly was measured again after 1 h and after 1 month. The diameter response of an arterial and venous vessel segment was measured continuously by a Dynamic Vessel Analyzer (DVA, IMEDOS, Jena). Each examination consisted of 50 s baseline measurement and three periods of 20-s flicker light provocation followed by 80 s observation. The mean of three provocational cycles was calculated as dynamic vessel response.
  
  
  RESULTS
  A significant correlation of the flicker response parameters between the right and left eyes was found. Arterial and venous baseline diameter, flicker light dilation, AVDQ, and BP did not change significantly between the first and follow-up examinations. There was no correlation between changes of BP and changes of vessel diameter parameters in the follow-up exams.
  
  
  CONCLUSIONS
  Flicker-evoked dilation of retinal arterioles measured by the DVA is characterized under similar conditions by small variance after short and medium-length time periods. Therefore, this parameter is suitable as a functional parameter of the regulation ability of retinal arteries.
authors.affiliation: Augenarztpraxis, Rudolstadt. e_a_nagel@t-online.de
authors.forename: E
authors.initials: E
authors.lastname: Nagel
authors.forename: W
authors.initials: W
authors.lastname: Vilser
authors.forename: A
authors.initials: A
authors.lastname: Fink
authors.forename: T
authors.initials: T
authors.lastname: Riemer
mesh_terms: D019412:Anatomy, Cross-Sectional / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008027:Light; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation / Q000379:methods*; D015203:Reproducibility of Results; D012161:Retinal Artery / Q000033:anatomy & histology* / Q000528:radiation effects*; D012680:Sensitivity and Specificity; D014664:Vasodilation / Q000528:radiation effects*