title: Choroidal blood flow and progression of age-related macular degeneration in the fellow eye in patients with unilateral choroidal neovascularization.
abstract: OBJECTIVE
  Cardiovascular risk factors such as smoking, hypertension, and atherosclerosis seem to play an important role in the development of choroidal neovascularization (CNV). Recent studies have also provided evidence suggesting that choroidal and retinal blood flow is decreased in patients with AMD. On the basis of these results, the hypothesis for this study was that lower choroidal blood flow is associated with an increased risk of CNV in patients with AMD.
  
  
  METHODS
  Forty-one patients with unilateral choroidal neovascular AMD were included in this observational longitudinal study. The fellow eyes of the patients served as study eyes. Subfoveal choroidal blood flow (FLOW) and fundus pulsation amplitude (FPA) were assessed with laser Doppler flowmetry and laser interferometry, respectively. A multivariate COX-regression model was used to test the hypothesis that low choroidal perfusion parameters are associated with the development of CNV.
  
  
  RESULTS
  Of the 37 patients that were followed up until the end of the study, 17 developed CNV and 20 did not. The univariate COX-regression analysis shows that lower FLOW, systolic blood pressure, intraocular pressure, and FPA are risk factors for development of CNV. Moreover, the more advanced the AMD in the study eye, the higher the risk for CNV to develop in the fellow eye. Multivariate COX regression analysis indicated that only FLOW (P = 0.0071), FPA (P = 0.0068), and staging (P = 0.031) had statistically significant influences on the progression to CNV.
  
  
  CONCLUSIONS
  The present study indicates that lower choroidal perfusion is a risk factor for the development of CNV in the fellow eye of patients with unilateral CNV.
authors.affiliation: Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.
authors.forename: Agnes
authors.initials: A
authors.lastname: Boltz
authors.forename: Alexandra
authors.initials: A
authors.lastname: Luksch
authors.forename: Barbara
authors.initials: B
authors.lastname: Wimpissinger
authors.forename: Noemi
authors.initials: N
authors.lastname: Maar
authors.forename: Günther
authors.initials: G
authors.lastname: Weigert
authors.forename: Sophie
authors.initials: S
authors.lastname: Frantal
authors.forename: Werner
authors.initials: W
authors.lastname: Brannath
authors.forename: Gerhard
authors.initials: G
authors.lastname: Garhöfer
authors.forename: Erdem
authors.initials: E
authors.lastname: Ergun
authors.forename: Michael
authors.initials: M
authors.lastname: Stur
authors.forename: Leopold
authors.initials: L
authors.lastname: Schmetterer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D002829:Choroid / Q000098:blood supply*; D020256:Choroidal Neovascularization / Q000503:physiopathology*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007368:Interferometry; D007429:Intraocular Pressure; D017078:Laser-Doppler Flowmetry; D008268:Macular Degeneration / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow / Q000502:physiology; D012307:Risk Factors