Macular edema is the thickening or swelling of the eye's macula, the tissue at the center of the retina responsible for pinpointing vision, as described by EyeSmart. When blood vessels in the retina begin leaking fluids, the macula begins to lose function, causing mild to severe loss of vision.
Untreated macular edema is the leading cause of vision loss in diabetic individuals. It is a common complication of diabetic retinopathy, but it can also result from retinal vein occlusion, age-related macular degeneration, blockage of the retinal veins and certain genetic conditions, according to EyeSmart. It may also occur as a side effect of certain medications. Patients who undergo cataract surgery have a greater risk of developing cystoid macular edema due to irritated blood vessels.
Symptoms of macular edema include distorted vision, a pinkish tint to vision, light sensitivity and blurred central vision, as described by Natural Eye Care. Common treatment options include anti-inflammatory eye drops, oral medications and injections, and vision loss is rarely permanent. Most patients experience a full recovery within two to 15 months. Doctors diagnose macular edema using fluorescein angiography and optical coherence tomography, which can measure the thickness of the macula, as confirmed by the Massachusetts Eye Research & Surgery Institution.