title: Retinal vascular changes following intravitreal ranibizumab injections for neovascular AMD over a 1-year period.
abstract: OBJECTIVE
  To assess retinal vascular calibre changes in eyes with neovascular age-related macular degeneration (AMD), treated with intravitreal anti-vascular endothelial growth factor agents, over a 1-year period and compare any such changes to untreated fellow eyes.
  
  
  METHODS
  Treatment naïve patients with neovascular AMD received three consecutive intravitreal injections of ranibizumab, followed by a pro re nata dosing regimen up to 1 year, with the aim of maintaining a 'fluid-free' macula. Retinal arteriolar and venular calibre was measured from digital fundus photographs at baseline and at three monthly intervals to 1 year, and summarised as central retinal artery equivalent (CRAE) and central retinal venular equivalent (CRVE), respectively.
  
  
  RESULTS
  A total of 53 injected eyes and 41 fellow, non-injected eyes were analysed. At baseline, there were no differences in retinal vascular calibre between injected and non-injected eyes (mean CRAE (SD) 144.93 (14.07) vs 145.74 (13.10) μm, P=0.80 and mean CRVE (SD) 216.23 (25.93) vs 219.91 (22.82) μm, P=0.53). Over a 12-month period, retinal venular calibre dilatation occurred in injected eyes (mean CRVE change +5.71 (14.71) μm, P=0.007), with no change in retinal arterioles, +0.69 (14.71) μm, P=0.68. In non-injected eyes, arteriolar narrowing occurred as a whole, mean CRAE change -4.20 (7.00) μm, P=0.001, over 12 months, with a trend for narrowing in venules, -2.16 (11.56) μm, P=0.28. In injected eyes, after controlling for covariates, the changes in CRVE over 12 months mirrored improvements in macular thickness, -0.06 (-0.005, -0.11) μm, P=0.04, and visual acuity, +9.66 (-0.30, +19.32) μm, P=0.06.
  
  
  CONCLUSIONS
  Intravitreal ranibizumab significantly dilated retinal venules after a 1-year period.
authors.affiliation: Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.
authors.forename: S S
authors.initials: SS
authors.lastname: Wickremasinghe
authors.forename: J
authors.initials: J
authors.lastname: Xie
authors.forename: R H
authors.initials: RH
authors.lastname: Guymer
authors.forename: T Y
authors.initials: TY
authors.lastname: Wong
authors.forename: R
authors.initials: R
authors.lastname: Kawasaki
authors.forename: S
authors.initials: S
authors.lastname: Qureshi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage*; D001160:Arterioles / Q000187:drug effects; D005260:Female; D006801:Humans; D058449:Intravitreal Injections; D008268:Macular Degeneration / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D008297:Male; D011446:Prospective Studies; D000069579:Ranibizumab; D012169:Retinal Vein / Q000187:drug effects*; D014699:Venules / Q000187:drug effects; D014792:Visual Acuity / Q000502:physiology
chemical_list: D020533:Angiogenesis Inhibitors; D061067:Antibodies, Monoclonal, Humanized; D000069579:Ranibizumab