Cystoid Macular Edema

Cystoid macular edema, commonly called CME, is a disorder that affects the retina, the layer of light-sensing cells lining the back of your eye. The retina transforms incoming light rays into signals, which then travel through the optic nerve to your brain, where they are interpreted as visual images. Cystoid macular edema (CME) refers to the accumulation of fluid-filled, cyst-like structures within the macula—the region of the retina responsible for central vision. As a consequence, the macula becomes swollen due to this fluid buildup.

Symptoms of Cystoid Macular Edema

The primary symptom of cystoid macular edema (CME) is central vision that appears blurred or distorted. Importantly, CME does not impact peripheral (side) vision. Additional symptoms may include vision with a pinkish tint, dimness, or heightened sensitivity to light. Occasionally, CME may be present even when no noticeable visual loss occurs. Your ophthalmologist (Eye M.D.) can identify CME through a comprehensive eye examination, often involving specialized eye photographs taken using techniques such as fluorescein angiogram or optical coherence tomography (OCT).

Causes of Cystoid Macular Edema

Although the exact causes of CME are not known, it can be associated with:

• Retinal vein occlusion (blockage of a blood vessel in your retina).
• uveitis (inflammation of the uvea, the outermost layer of your eye).
• diabetes.
• eye surgery.
• eye trauma.
• side effects from medication.

It most commonly occurs after cataract surgery. About 3% of all cataract surgery patients will experience decreased vision due to CME, usually within a few months after surgery. If CME occurs in one eye, there is an increased risk (as high as 50%) that it will also occur in your other eye.

Treatments For Cystoid Macular Edema

Depending on the cause of CME, treatment may include some of the following methods:

Anti-inflammatory treatments, such as steroid drops, pills, or injections, can be effective. Additionally, laser surgery can repair leaky blood vessels, and a surgical procedure known as vitrectomy may be performed to remove the gel-like substance called the vitreous from the eye. Fortunately, most patients with CME respond well to treatment, and their vision improves, although the healing process may be gradual and extend over several months.