Comparison of Intravitreal Dexamethasone Implant and Posterior Subtenon Triamcinolone Injection in the Treatment of Diabetic Macular Edema in Vitrectomized Eyes

Abstract

Introduction: The aim of this study was to compare posterior subtenon triamcinolone (PSTA) application and intravitreal dexamethasone phosphate (DEX) implant in the treatment of diabetic macular edema (DME) in vitrectomized eyes. Methods: This retrospective study included 64 (48.12%) patients who received PSTA and 69 (51.88%) patients who received DEX implants in DME treatment after vitrectomy. Best corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure (IOP) were analyzed before injection; at 1, 3, and 6 months after injection. The postinjection values were statistically compared with the preinjection value. Results: All postinjection CMT values in both groups were lower than the preinjection value (p < 0.05 for all). There were statistically significant increases in all postinjection BCVAs of the DEX group and postinjection 1-month BCVA of the PSTA group (p < 0.05 for all). However, there was no significant difference in BCVA values of the PSTA group at 3 and 6 months after injection (p > 0.05 for both). There was no statistically significant difference in all postinjection IOP values of the PSTA group (p > 0.05 for all). However, significant increases in IOP were observed in the DEX group at 1 and 3 months after injection (p < 0.05 and p = 0.02, respectively). The number of additional injections between the 3rd and 6th months after the initial injection was statistically higher in the PSTA group (p = 0.006). Conclusion: Both intravitreal DEX and PSTA administration are effective in the treatment of DME after vitrectomy. However, visual improvement persisted longer, and the need for additional injections was less in patients who received DEX.