PT - JOURNAL ARTICLE AU - Sanjeewa S Wickremasinghe AU - Samantha Fraser-Bell AU - Elizabeth Alessandrello AU - Hemal Mehta AU - Mark C Gillies AU - Lyndell L Lim TI - Retinal vascular calibre changes after intravitreal bevacizumab or dexamethasone implant treatment for diabetic macular oedema AID - 10.1136/bjophthalmol-2016-309882 DP - 2017 Oct 01 TA - British Journal of Ophthalmology PG - 1329--1333 VI - 101 IP - 10 4099 - http://bjo.bmj.com/content/101/10/1329.short 4100 - http://bjo.bmj.com/content/101/10/1329.full SO - Br J Ophthalmol2017 Oct 01; 101 AB - Purpose 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).Methods 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.Results 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).Conclusions 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.Trial registration number NCT01298076.