The macula is the central portion of the retina that is responsible for high-acuity or detailed vision. One can often suffer a loss of peripheral vision without noticing the difference, but if the macula becomes damaged it affects the central vision and is usually immediately noticeable. Macular edema occurs when there is a buildup of fluid in the macula causing swelling and thickening of the macula, ultimately leading to distorted vision. Symptoms can vary with macular edema from slightly blurry or wavy vision to significant vision loss.
Macular edema can be caused by a number of disease processes or as a side effect of surgery. Diseases such as age-related macular degeneration and diabetes are often to blame for varying degrees of macular edema. Patients that have surgery inside the eye can also experience macular edema, although most cases are mild and resolve with treatment. Other causes of macular edema include some inflammatory diseases such as cytomegalovirus (CMV), histoplasmosis, and sarcoidosis. Macular edema can also be caused by conditions that result in blocked retinal veins, including such conditions as glaucoma, high blood pressure, diabetes and atherosclerosis related to the aging process.
Treatments for macular edema can range from treating the underlying causes (such as high blood pressure) to the use of lasers and medications, including steroid and nonsteroid drops as well as anti-VEGF injections where medications are injected directly into the eye. In more severe cases, surgery in the form of a vitrectomy may be required to treat this condition.