What is Cystoid Macular Edema?

Cystoid macular edema, typically referred to as CME, affects the retina, the portion of the eye responsible for sight. Fluid fills small, painless blister-like lesions on the macula, which is the part of the retina that provides detailed central vision.

What causes Cystoid Macular Edema?

The cause of this swelling is unknown; it sometimes accompanies diabetes, retinal vein occlusion, or uveitis. However, it is most commonly found in patients who have undergone cataract surgery within the last year. Usually, about 3% of post-operative cataract surgery patients are diagnosed with CME, typically within the first 4 months after surgery. If a patient develops CME in one eye post-operatively, there is a 50% chance that that patient will experience the same problem in the second eye post-operatively.

What are the symptoms of Cystoid Macular Edema?

The primary symptom of CME is blurred vision that affects the central portion of the patient's visual field, but, not the peripheral portion. In some cases, there may also be some associated retinal inflammation. Not all CME patients experience blurred vision, but, they still show signs of it upon dilated exam. Diagnosis requires an evaluation of symptoms, signs, and sometimes certain diagnostic tests. Most helpful in the diagnosis of CME is a test called a fluorescein angiogram. In this test, due is injected through the patient's arm and observed as it flows through the eye's blood vessels and retina.

How is Cystoid Macular Edema treated?

Treatment of this problem usually involves eye drops, pills, or injections of steroids. Occasionally, glaucoma may result from treatment of CME, and this must be treated with glaucoma medications which act to decrease the eye pressure to acceptable levels.