title: Short posterior ciliary artery, central retinal artery, and choroidal hemodynamics in brimonidine-treated primary open-angle glaucoma patients.
abstract: OBJECTIVE
  Malfunction in peripapillary hemodynamics has been suggested to play a major part in the pathogenesis of primary open-angle glaucoma (POAG). The aim of this study was to determine whether topically applied brimonidine can influence blood hemodynamic characteristics associated with the perioptic short posterior ciliary arteries (SPCAs), central retinal artery (CRA), and choroidal vascular system in POAG patients.
  
  
  METHODS
  Randomized clinical trial. In this prospective, institutional, double-masked, vehicle-controlled, randomized clinical trial, the intraocular pressure (IOP) and vascular dynamics of the SPCAs, CRA, and choroidal vascular system were analyzed in both eyes of 17 POAG patients, before and after treatment with 0.2% brimonidine for 4 weeks.
  
  
  RESULTS
  Mean IOP reduction was significant (18.7%) following treatment with brimonidine. However, no clear changes were recorded with respect to blood perfusion parameters (peak systolic velocity, end-diastolic velocity, pulsatility, and resistance indices) associated with the SPCAs and CRA or the choroidal ocular pulse amplitude.
  
  
  CONCLUSIONS
  Topical treatment of brimonidine to POAG patients causes a significant reduction of IOP, but blood hemodynamic properties associated with the SPCAs, CRA, and choroidal vascular systems appeared unaffected. Topically applied brimonidine, therefore, appears not to constrict or dilate peripapillary blood vessels.
authors.affiliation: Department of Ophthalmology, University of Dresden, Dresden, Germany. k.g.schmidt@gmx.de
authors.forename: Karl-Georg
authors.initials: KG
authors.lastname: Schmidt
authors.forename: Volker
authors.initials: V
authors.lastname: Klingmüller
authors.forename: Scott M
authors.initials: SM
authors.lastname: Gouveia
authors.forename: Neville N
authors.initials: NN
authors.lastname: Osborne
authors.forename: Lutz E
authors.initials: LE
authors.lastname: Pillunat
mesh_terms: D000287:Administration, Topical; D000316:Adrenergic alpha-Agonists / Q000627:therapeutic use*; D001783:Blood Flow Velocity; D000068438:Brimonidine Tartrate; D002829:Choroid / Q000098:blood supply* / Q000000981:diagnostic imaging; D019842:Ciliary Arteries / Q000000981:diagnostic imaging / Q000502:physiology*; D004311:Double-Blind Method; D005260:Female; D005902:Glaucoma, Open-Angle / Q000188:drug therapy / Q000503:physiopathology*; D006801:Humans; D007429:Intraocular Pressure; D017078:Laser-Doppler Flowmetry; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011810:Quinoxalines / Q000627:therapeutic use*; D012161:Retinal Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D014463:Ultrasonography
chemical_list: D000316:Adrenergic alpha-Agonists; D011810:Quinoxalines; D000068438:Brimonidine Tartrate