title: Retinal vascular calibre changes after intravitreal bevacizumab or dexamethasone implant treatment for diabetic macular oedema.
abstract: To compare changes in retinal vascular calibre after 2 years of treatment with intravitreal bevacizumab (BVZ) or dexamethasone implant (DEX) in patients with centre-involving diabetic macular oedema (DMO).
  
  
  
  At baseline, 88 eyes of 61 patients with DMO were recruited in a prospective, multicentre, randomised, single-masked clinical trial. Of these subjects, 22 BVZ-treated (52%) and 22 DEX-treated (48%) eyes of 34 patients (56%) had gradable retinal photographs at both the baseline and 24-month visits. Retinal vascular calibre was measured from digital fundus photographs and summarised as central retinal artery (CRAE) and vein (CRVE) equivalents in all gradable eyes at baseline and 24 months.
  
  
  
  At 24 months, 40.9% of BVZ and 45.5% of DEX eyes gained 10 or more letters (p=0.77). There was concurrent reduction in mean central macular thickness, -157.7 μm in BVZ and -192.5 μm in DEX-treated eyes (p=0.40). DEX-treated eyes showed a statistically significant reduction in CRVE compared with BVZ-treated eyes, with a mean change from baseline of -31.78 to +4.34 µm, respectively (p<0.001). CRAE showed a non-statistically significant trend towards reduction over time in DEX-treated eyes compared with BVZ-treated eyes, with a mean change from baseline of -6.09 and +1.66, respectively (p=0.077).
  
  
  
  DEX had a significant narrowing effect on venular diameter in eyes with DMO not seen with BVZ. The changes in retinal vascular calibre suggest that these agents have a differing actions effects retinal vasculature and thereby suggest a potentially different mechanism of action on reducing DMO.
  
  
  
  NCT01298076.
authors.affiliation: Centre for Eye Research Australia, University of Melbourne, Melbourne, Victoria, Australia.|Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.
authors.forename: Sanjeewa S
authors.initials: SS
authors.lastname: Wickremasinghe
authors.affiliation: Department of Ophthalmology, Save Sight Institute, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Samantha
authors.initials: S
authors.lastname: Fraser-Bell
authors.affiliation: Centre for Eye Research Australia, University of Melbourne, Melbourne, Victoria, Australia.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Alessandrello
authors.affiliation: Department of Ophthalmology, Save Sight Institute, University of Sydney, Sydney, New South Wales, Australia.|Royal Free London NHS Foundation Trust, London, UK.
authors.forename: Hemal
authors.initials: H
authors.lastname: Mehta
authors.affiliation: Department of Ophthalmology, Save Sight Institute, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Mark C
authors.initials: MC
authors.lastname: Gillies
authors.affiliation: Centre for Eye Research Australia, University of Melbourne, Melbourne, Victoria, Australia.|Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.
authors.forename: Lyndell L
authors.initials: LL
authors.lastname: Lim
mesh_terms: D000368:Aged; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage*; D000068258:Bevacizumab / Q000008:administration & dosage*; D003907:Dexamethasone / Q000008:administration & dosage*; D003930:Diabetic Retinopathy / Q000188:drug therapy* / Q000473:pathology; D004343:Drug Implants; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage*; D006801:Humans; D058449:Intravitreal Injections; D008269:Macular Edema / Q000188:drug therapy* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012171:Retinal Vessels / Q000473:pathology*; D014792:Visual Acuity
chemical_list: D020533:Angiogenesis Inhibitors; D004343:Drug Implants; D005938:Glucocorticoids; D000068258:Bevacizumab; D003907:Dexamethasone
keywords: Imaging; Macula; Treatment Medical; Vision