Pathogenesis of diabetic macular edema (DME) involves inflammation, angiogenesis, and oxidative stress processes provoked mainly by cytokines such as interleukin (IL)-6, 8, and monocyte chemotactic protein, and vascular endothelial growth factor (VEGF). Vision loss associated with diabetic retinopathy is most commonly caused by DME, which affects approximately 7% of all diabetic patients. Several therapeutic options are available for treating DME. Evidence for the use of these therapies is accumulating; however, the optical treatment choice remains unclear. In recent years, using intravitreal anti-VEGF agents to treat DME has been shown to be beneficial. Anti-VEGF injections are generally considered suitable first-line therapy for center-involved DME and are effective in improving visual acuity (VA), with 10% to 40% of patients achieving significant improvement in best-corrected visual acuity (BCVA) after 1 year of treatment.~The management of DME is complex, and often multiple treatment approaches are needed. Although anti-VEGF agents were effective for the treatment of DME, there is a proportion of patients who do not achieve optimal response to these agents, presenting refractory or persistent DME. Intravitreal administration of steroids for the treatment of DME has also been studied for many years due to their well-known, widespread, anti-inflammatory effects. Dexamethasone implant is a slow-release dexamethasone delivery system developed for intravitreal administration that has recently been introduced as a therapeutic option in DME.
The purpose of the investigator's study is to evaluate the efﬁcacy and safety proﬁle of the pro re nata (PRN) regimen to 12 months by using intravitreal dexamethasone implant in eyes with treatment-naive diabetic macular edema patients.