title: Short-term effects of a single intravitreal bevacizumab injection on retinal vessel calibre.
abstract: OBJECTIVE
  The aim was to investigate the short-term effects of a single intravitreal bevacizumab injection on the retinal vessel calibre in patients with neovascular age-related macular degeneration and in patients with diabetic macular oedema.
  
  
  METHODS
  Twelve patients with neovascular age-related macular degeneration and eight patients with diabetic macular oedema were included in the study. All patients received an intravitreal injection of 1.25 mg bevacizumab. Red-free fundus photographs (35°) were acquired with a fundus camera at baseline and one day, one week and one month after the intravitreal injection. Measurements of retinal vessel diameter were made of the supero-temporal retinal venule and arteriole using the software available on the IMAGEnet program.
  
  
  RESULTS
  Although there appeared to be a trend towards vasoconstriction for the measurements in the diabetic macular oedema group (both for arterioles and venules at day 7) and the age-related macular degeneration group (for venules at day 1 and for arterioles at day 7), it did not reach statistical significance (p > 0.05). Optical coherence tomography revealed a significant decrease in foveal thickness measurements in both groups at the one month visit compared with baseline.
  
  
  CONCLUSIONS
  The results suggest that intravitreal injection of bevacizumab might induce retinal vasoconstriction; however, low numbers of subjects might have prevented the difference from reaching statistical significance. Further studies with a larger number of subjects would reveal the effect of intravitreal anti-vascular endothelial growth factor treatment on retinal vessel diameters more clearly.
authors.affiliation: Department of Ophthalmology, Yeditepe University Medical Faculty, Balmumcu, Besiktas, İstanbul, Turkey. statlipi@yahoo.com
authors.forename: Sinan
authors.initials: S
authors.lastname: Tatlipinar
authors.forename: Umut Aslı
authors.initials: UA
authors.lastname: Dinç
authors.forename: N Melda
authors.initials: NM
authors.lastname: Yenerel
authors.forename: Ebru
authors.initials: E
authors.lastname: Görgün
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage*; D000068258:Bevacizumab; D003930:Diabetic Retinopathy / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy*; D005260:Female; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D005654:Fundus Oculi; D006801:Humans; D058449:Intravitreal Injections; D008268:Macular Degeneration / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D008269:Macular Edema / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015861:Retinal Neovascularization / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy*; D012171:Retinal Vessels / Q000187:drug effects* / Q000503:physiopathology; D013997:Time Factors; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome; D042461:Vascular Endothelial Growth Factor A; D014664:Vasodilation / Q000187:drug effects*; D014792:Visual Acuity
chemical_list: D020533:Angiogenesis Inhibitors; D061067:Antibodies, Monoclonal, Humanized; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab