Objective: We aimed to compare visual and anatomical outcome in vitrectomized and non-vitrectomized eyes treated with dexamethasone (DEX) implant due to diabetic macular oedema (DMO). Design: Multicenter, retrospective, interventional study. Participants: 236 eyes from 234 patients with DMO with or without previous vitrectomy performed with follow-up of 12 months. Methods: Records were reviewed for cases of DMO treated with DEX implant in vitrectomized and not vitrectomized eyes. Best corrected visual acuity (BCVA), central subfoveal thickness (CST), and intraocular pressure (IOP) were recorded at baseline and 12 months after treatment with DEX implants. Correlations between vitreous status and visual and anatomical outcome, as well as safety profile were analysed. Main outcome measures: BCVA and CST over follow-up period. Secondary outcomes: cataract rate formation, intraocular pressure increase, number of implants needed. Results: The non-vitrectomized group included 130 eyes (55.1%), the vitrectomized group included 106 eyes (44.9%). The groups were well balanced for age and gender (p = 0.540, and p = 0.053, respectively). Both groups showed statistically significant improvement in BCVA and CST (for all groups: p < 0.001). There was no significant difference between the groups in terms of change in vision (p = 0.89) and anatomy (p = 0.65). The mean number of DEX implants given during follow-up was 3.5 in both groups, and there was no significant difference between the groups (p = 0.81). Conclusion: We demonstrated similar anatomical and functional efficacy of DEX implant in non-vitrectomized and vitrectomized eyes. Its efficacy was not influenced by full vitrectomy for diabetic retinopathy complications. Safety profile was well balanced between groups.
