Cystoid Macula Oedema

Cystoid macula oedema, commonly called CME, is a painless disorder which affects the retina, the light-sensitive inner lining of the eye. When this condition is present, clear fluid fills multiple cyst-like (cystoid) formations in the macula, the portion of the retina responsible for central or "straight ahead" vision. This creates macula swelling, or oedema. Although the exact causes of cystoid macula oedema are not known, it may accompany a variety of diseases such as retinal vein occlusion, uveitis or diabetes. It most commonly occurs after cataract surgery. About two percent of those who have cataract extractions will experience decreased vision due to cystoid macula oedema in the first year, usually from two to four months after surgery.

If the disorder appears in one eye, there is an increased risk-as high as 50%--that it will also affect the second eye. Fortunately, however, most patients recover their vision after some time.

What are the symptoms of cystoid macula oedema?

The most common symptoms of cystoid macula oedema is blurred or decreased central vision (cystoid macula oedema does not affect peripheral or side vision).

There may also be painless retinal inflammation or swelling. However, the condition may be present even when no visual loss occurs.

How can cystoid macula oedema be treated?

Signs of retinal inflammation are usually treated with anti-inflammatory medications, including cortisone-like drugs (steroid drops, tablets or local injections) or anti-inflammatory drugs. Diuretics such as Diamox may help to reduce the swelling in some cases.

If the vitreous (the clear, gel-like substance that fills the centre of the eye) is believed to be the source of the problem, laser surgery might be recommended.

Another procedure called a vitrectomy can be used to suction the vitreous out of the eye and replace it with a clear solution.

A great deal of research is presently being conducted to determine the causes of cystoid macula oedema. Hopefully, this research will lead to more exact prevention and treatment measures in the near future.