Treatment of diabetic macular edema with sustained-release glucocorticoids: intravitreal triamcinolone acetonide, dexamethasone implant, and fluocinolone acetonide implant

Introduction: Diabetic macular edema (DME) can be treated with intravitreal glucocorticoids, particularly triamcinolone acetonide, dexamethasone (DEX), and fluocinolone acetonide (FA). Areas covered: The pathophysiology of DME includes multiple growth factors such as VEGF and also inflammatory mediators. Glucocorticoids act on DME through multiple pathways, and current research into their efficacy, safety, and therapeutic potential when administered intravitreally is discussed. Conclusion: The intravitreal route of administration minimizes systemic side effects of glucocorticoids. Furthermore, sustained-release low-dose delivery via the DEX implant or the FA implant will limit frequent intravitreal injection and possibly some cost associated with intravitreal anti-VEGF therapy. In addition, the durable action of these treatments facilitates combination therapy. Patients can receive these implants as foundational therapy, and then receive additional treatment with laser or intravitreal anti-VEGF agents as combination therapy, which may conceivably provide some synergistic benefit. While the FA implant lasts much longer than the DEX implant, potentially decreasing the visit and treatment burden on patients and their families, the FA implant appears to have a greater risk of inducing ocular hypertension and cataract. However, these modalities have not been directly compared in a clinical trial and there is insufficient evidence to draw more elaborate conclusions.