Macular edema is swelling of the macula, the small area of the retina responsible for central vision. The edema is caused by fluid leaking from retinal blood vessels. Central vision, used for reading and other close detail work, is affected. Because the macula is surrounded by many tiny blood vessels, anything affecting them, such as a medical condition affecting blood vessels elsewhere in the body or an abnormal condition originating in the eye, can cause macular edema.
Retinal blood vessel obstruction, eye inflammation, and age-related macular degeneration have all been associated with macular edema. The macula may also be affected by swelling following cataract extraction, though typically this resolves itself naturally.
Treatment seeks to remedy the underlying cause of the edema. Eyedrops, injections of cortisone around the eye or laser surgery can be used to treat a macular edema. Recovery depends on the severity of the condition causing the edema.