Diabetic Macular Edema
Also known as: DME, Diabetic macular oedema
Overview
Diabetic macular edema (DME) is the accumulation of fluid in the central retina due to breakdown of the blood–retinal barrier in diabetes, and it is the most common cause of vision loss in patients with diabetic retinopathy. It can occur at any stage of retinopathy. OCT has made diagnosis and monitoring precise, and anti-VEGF therapy is the first-line treatment for center-involving disease.
- Mechanism
- Blood–retinal barrier breakdown
- Location
- Central macula
- Key test
- Macular OCT
- First-line therapy
- Intravitreal anti-VEGF
Key clinical points
- DME is the leading cause of vision loss in diabetic retinopathy and can occur at any stage.
- Center-involving DME with vision loss is the primary indication for treatment.
- OCT is essential for diagnosis and for tracking treatment response.
- Anti-VEGF injections are first-line; corticosteroids and focal laser are adjuncts.
- Systemic control of glucose, blood pressure, and lipids supports ocular outcomes.
Pathophysiology
Chronic hyperglycemia damages retinal capillaries and disrupts the blood–retinal barrier, allowing fluid and lipid to accumulate in the macula. When this edema involves the center of the macula, it degrades central acuity. DME is distinct from, but often coexists with, the vascular changes used to stage diabetic retinopathy.
Diagnosis
OCT is the standard for detecting and quantifying macular edema and distinguishing center-involving from non-center-involving disease. Fundus examination and fluorescein angiography identify leakage and ischemia. Because DME can be present without dramatic symptoms early on, OCT screening in patients with retinopathy is important.
Treatment
Center-involving DME with reduced vision is treated first-line with intravitreal anti-VEGF therapy, which reduces edema and can improve acuity. Corticosteroid implants are useful in selected eyes, including those with limited anti-VEGF response or specific clinical circumstances. Focal/grid laser has a residual role for certain non-center-involving disease.
Optimizing systemic control of glucose, blood pressure, and lipids complements ocular therapy and reduces overall progression risk.
Diabetic Macular Edema videos
Frequently asked questions
- What is center-involving diabetic macular edema?
- Center-involving DME is fluid accumulation affecting the very center of the macula (the fovea). It is the form most associated with vision loss and is the primary indication for anti-VEGF treatment.
- Why is OCT important in diabetic macular edema?
- OCT precisely detects and measures macular fluid, distinguishes center-involving from non-center-involving edema, and tracks response to therapy, making it central to both diagnosis and monitoring.
- Can diabetic macular edema occur without severe retinopathy?
- Yes. DME can develop at any stage of diabetic retinopathy, including relatively mild disease, which is why macular evaluation is part of routine monitoring in patients with diabetes.
References & further reading
Related conditions
Diabetic Retinopathy
Diabetic retinopathy is a microvascular complication of diabetes mellitus and a leading cause of vision loss among working-age adults. It progresses from non-proliferative changes—microaneurysms, hemorrhages, and exudates—to proliferative disease with neovascularization that risks vitreous hemorrhage and tractional detachment. Glycemic and blood pressure control plus timely screening are the foundation of prevention.
Clinical overviewRetinaRetinal Vein Occlusion
Retinal vein occlusion (RVO) is one of the most common retinal vascular disorders, caused by thrombotic obstruction of a retinal vein that leads to hemorrhage, macular edema, and, in ischemic cases, neovascularization. It is classified as branch or central depending on the site of occlusion. Vision loss most often results from macular edema, which is treated effectively with anti-VEGF therapy.
Clinical overviewRetinaAge-Related Macular Degeneration
Age-related macular degeneration (AMD) is a progressive disease of the central retina and a leading cause of irreversible central vision loss in people over 50. It is divided into non-neovascular (dry) disease, marked by drusen and, in advanced form, geographic atrophy, and neovascular (wet) disease, in which choroidal neovascularization threatens rapid vision loss. Anti-VEGF therapy transformed the prognosis of wet AMD.
Clinical overview