Effects of dexamethasone treatment on serous retinal detachment in ranibizumab-resistant diabetic macular edema

Purpose: To evaluate outcome of intravitreal dexamethasone implant (IDI) treatment on serous retinal detachment (SRD) in patients with ranibizumab-resistant diabetic macular edema (DME). Materials and methods: Forty-eight eyes of 48 patients with DME resistant to ranibizumab were enrolled in this retrospective and comparative study. Patients were divided into two groups according to presence of serous retinal detachment: (1) SRD or (2) non-SRD groups. All patients had at least three monthly ranibizumab injections, after which they were treated with IDI. The best-corrected visual acuity (BCVA), central retinal thickness (CRT), use of antiglaucomatous drugs, and presence of cataract progression were noted at 1, 3, and 6 months post-IDI treatment. Results: There was not any statistically significant difference in terms of baseline characteristics of the patients. The mean CRT was declined in both groups at 1, 3, and 6 months (p < 0.001). After IDI treatment, the mean BCVA was improved in both groups at 1, 3, and 6 months (p < 0.001). When groups were compared, the change in CRT was higher in the SRD group (p = 0.018), while there was no statistically significant difference between groups in terms of BCVA changes (p = 0.448). Conclusion: The presence of SRD resulted in higher anatomical gain. SRD had no effects on visual changes after dexamethasone treatment in patients with ranibizumab-resistant DME.