An epiretinal membrane is a thin sheet of fibrous tissue that develops on the surface of the macula and can cause problems with central vision.
What is an epiretinal membrane?
If you think of your eye as a camera, the retina is like the photographic film. It is a very thin layer of tissue, which is sensitive to the image focused on it, and sends information to the brain. At the very centre of the retina is the macula. This is a very special area of the retina, which we use for reading and recognising complex shapes.
Sometimes, scar tissue forms which grows across the macula. As the membrane contracts, it causes distortion of the retinal tissue. If this happens, the macula cannot work normally. This affects the vision, particularly for reading and other visually demanding tasks, but it does not cause total blindness.
What causes an epiretinal membrane?
Most epiretinal membranes happen because the vitreous (the jelly inside the eye) pulls away from the retina. This most commonly happens to people over the age of 50. The membrane may also form following eye surgery or inflammation inside the eye.
How epiretinal membranes affect vision
While the scar tissue is developing, it does not appear to affect your vision. However, when it stops growing, it contracts (shrinks) and causes distortion of your central vision – for example, straight lines appear wavy or crooked in appearance, and reading is difficult. Depending on the severity of this distortion, you might notice a substantial loss of central vision.
Treatment for an epiretinal membrane
The only way to treat an epiretinal membrane is by having an operation called a vitrectomy. Eye drops or glasses are not effective. During the vitrectomy, the surgeon makes tiny cuts in your eye and removes the vitreous from inside. They then grasp and gently peel away the epiretinal membrane from the retina. We usually put small stitches in the eye. These dissolve naturally over about four to six weeks. At the end of the operation, we usually put a pad and shield over your eye to protect it. These will be removed the morning after your surgery.
Your doctor will help you to decide if surgery is appropriate for you. The main reason to proceed with the operation is to attempt to correct the distortion of your central vision. If you are not aware of any visual problems, you might not need to have surgery. However, if the distortion affects your ability to work, drive, read, or perform other important activities, you should consider having an operation. Some patients decide not to have an operation and accept the distorted central vision in the affected eye. This is reasonable, especially if the vision in the other eye is not affected. There is no “right” or “wrong” decision, as every person has different needs and priorities. In general, you should only go ahead with surgery if you find the distortion of your vision troublesome at the moment, and not as a preventative measure.