What are Epiretinal Membranes?
Epiretinal membranes are a thin, almost transparent layer of fibrous cellular material that forms as a ‘film’ over the macula at the back of your eye, resulting in difficulty seeing. It is a condition that is often confused with macular degeneration. Although both conditions do affect the macula, they actually have different symptoms and causes.
An epiretinal membrane will not cause total blindness – it will typically only affect the central vision in the affected eye, while peripheral or ‘side’ vision remains unaffected.
What causes Epiretinal Membranes?
The condition is caused by a thin sheet of fibrous tissue forming on the macula (the sharp focusing area at the back of your eye), it acts like a film through which it is harder to see.
This film can also contract like scar tissue, which can pull on the delicate retina at the back of your eye. This, in turn, causes ‘puckering’ of the macula, which can distort your vision and can also cause the retina to swell so it doesn’t work as well. This condition is known as a ‘macular pucker’.
In most cases, epiretinal membranes occur in people with no previous history of eye problems. It is usually caused by natural changes in the vitreous ‘gel’ inside the eye. These changes cause cells from the retina and other parts of the eye to be released into the vitreous ‘gel’, and they eventually settle on the macula, where they can form a membrane.
Occasionally, however, an epiretinal membrane can form as a result of a previous eye problem, such as a torn or detached retina, trauma, disease, blood vessel abnormality or other condition.
A diagnostic tool that aids in the detection of visual disturbances caused by such changes in the macula is called the Amsler Grid. In this test, a person looks with each eye separately at the small dot in the center of the grid. Patients with a macular disease may see wavy lines or some lines may be missing.
How are Epiretinal Membranes Treated?
Not all epiretinal membranes require treatment. If the condition is very mild, and has little or no effect on your vision, then treatment will generally be unnecessary. In more severe cases, epiretinal membrane surgery is generally necessary to remove the membrane.