title: Optical coherence tomography and vessel diameter changes after intravitreal bevacizumab in diabetic macular oedema.
abstract: OBJECTIVE
  To assess the effect of intravitreal bevacizumab on diabetic macular oedema (DMO) and retinal vessel calibres.
  
  
  METHODS
  We performed a consecutive case series study in which 10 consecutive eyes with diffuse DMO, two of which had not previously been treated, received an intravitreal injection of bevacizumab 1 mg, which was followed by two more injections at 6-week intervals. Fundus photography and optical coherence tomography (OCT) were carried out at baseline immediately before injection and at 1, 2.5 and 4 months after the first injection. Outcome measures were best corrected visual acuity (BCVA) in Early Treatment Diabetic Retinopathy Study letters, macular volume, foveal subfield thickness and vessel diameter measurement.
  
  
  RESULTS
  Intravitreal administration of bevacizumab was followed by a mean increase in BCVA of 7.3 +/- 17 (mean +/- standard deviation) letters between baseline and month 4, which was 1 month after the last injection (p < 0.0001). This was accompanied by a reduction in mean macular volume from 9.90 +/- 1.9 mm(3) to 8.96 +/- 2.4 mm(3) (p = 0.002) and in foveal subfield thickness from 447 +/- 117 microm to 388 +/- 117 microm (p = 0.03). Two eyes with early proliferative diabetic retinopathy lost all signs of proliferation without any evidence of fibrosis. Although there was a trend towards vasoconstriction, the changes in vessel diameters (arteries and veins) after 4 months of intravitreal Avastin injection were not statistically significant (p = 0.9 and p = 0.17, respectively). Foveal thickness in non-injected fellow eyes with DMO changed from 428 +/- 153 microm at baseline to 383 +/- 151 microm at 4 months (p = 0.1), which did not reach statistical significance.
  
  
  CONCLUSIONS
  Intravitreal bevacizumab 1 mg every 6 weeks was followed by a moderate reduction in DMO without normalization of foveal and macular thickness. Our observations suggest that a larger study where patients are examined sooner after injection is needed to elucidate the potential relationship between changes in retinal vessel diameters and thickness changes in DMO.
authors.affiliation: Department of Ophthalmology, Glostrup Hospital, University of Copenhagen, Glostrup, Denmark. waelsoliman73@yahoo.com
authors.forename: Wael
authors.initials: W
authors.lastname: Soliman
authors.forename: Martin
authors.initials: M
authors.lastname: Vinten
authors.forename: Birgit
authors.initials: B
authors.lastname: Sander
authors.forename: Kamell Abd El-Naser
authors.initials: KA
authors.lastname: Soliman
authors.forename: Sameer
authors.initials: S
authors.lastname: Yehya
authors.forename: Mohamed Saad Abdel
authors.initials: MS
authors.lastname: Rahman
authors.forename: Michael
authors.initials: M
authors.lastname: Larsen
mesh_terms: D000328:Adult; D000368:Aged; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage*; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized; D000068258:Bevacizumab; D002455:Cell Division / Q000187:drug effects; D003930:Diabetic Retinopathy / Q000188:drug therapy* / Q000473:pathology*; D005260:Female; D005584:Fovea Centralis / Q000187:drug effects / Q000473:pathology; D006801:Humans; D007267:Injections; D008269:Macular Edema / Q000188:drug therapy / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012171:Retinal Vessels / Q000187:drug effects / Q000473:pathology; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome; D014822:Vitreous Body
chemical_list: D020533:Angiogenesis Inhibitors; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000068258:Bevacizumab