title: Effect of hypertension on foveolar choroidal haemodynamics.
abstract: OBJECTIVE
  To assess the effect of systemic hypertension on the choroidal circulation in subjects with a normal eye examination.
  
  
  METHODS
  Laser Doppler flowmetry was used to determine relative choroidal blood velocity (Ch(vel)), volume (Ch(vol)), and flow (Ch(flow)) in the centre of the fovea. Measurements were obtained in 15 eyes of 15 subjects with systemic hypertension. The mean average duration of hypertension was 11 (SD 6) years. Findings obtained in these patients were compared with those of 15 eyes of 15 age matched healthy controls. All subjects had normal eye examinations.
  
  
  RESULTS
  No significant differences in Ch(vel), Ch(vol), and Ch(flow), were found between the subjects with and without systemic hypertension despite a 17% higher perfusion pressure (PP) in patients with hypertension. No significant correlation was found between mean arterial pressure or PP and the choroidal circulatory parameters. It was estimated that there is a 90% power to detect a 35% difference in Ch(flow) between the two groups.
  
  
  CONCLUSIONS
  Systemic hypertension does not seem to have a large effect on the choroidal circulation in hypertensive patients that are controlled by antihypertensive therapy. Further studies are needed to elucidate whether systemic hypertension has an effect on the choroidal circulation in patients with ocular diseases.
authors.affiliation: Scheie Eye Institute, University of Pennsylvania, 51 North 39th Street, Philadelphia, PA 19104, USA.
authors.forename: R M
authors.initials: RM
authors.lastname: Niknam
authors.forename: L S
authors.initials: LS
authors.lastname: Schocket
authors.forename: T
authors.initials: T
authors.lastname: Metelitsina
authors.forename: J C
authors.initials: JC
authors.lastname: DuPont
authors.forename: J E
authors.initials: JE
authors.lastname: Grunwald
mesh_terms: D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity; D001794:Blood Pressure; D002829:Choroid / Q000098:blood supply*; D005584:Fovea Centralis / Q000098:blood supply*; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D017078:Laser-Doppler Flowmetry; D008875:Middle Aged; D012039:Regional Blood Flow