Epiretinal membrane (ERM) is a condition where a sheet of naturally occurring cells develops on or above the surface of the central part of your retina, an area called the macula.
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ERM can affect vision if this sheet of cells starts to shrink, causing the retina to wrinkle up under it. This wrinkling of the retina can then cause distortion and blurring of your vision, as well as a possible reduction in your level of sight (how far down the letter chart you are able to read). However, it doesn’t cause you to lose all your vision and it isn’t painful.
ERM does not always cause sight problems. If you are not noticing any vision problems, then you may not need any treatment. Many epiretinal membranes do not get any worse and may never affect vision, so can just be left alone.
An epiretinal membrane is sometimes described as “scar tissue” on the retina. Other names for this include epi-macular membrane, macular pucker or cellophane maculopathy.
This page contains a summary of our information on epiretinal membrane. To read our full information, download our factsheet:
How does ERM affect vision?
Whether or not an epiretinal membrane will affect sight and how badly sight will be affected can be quite variable. In the early stages of its development, an epiretinal membrane may not cause any problems with vision.
However, if the membrane shrinks and wrinkles it can cause distortion of your central vision. Your vision can seem blurred and straight lines may look wavy or bent. You may find things like reading or seeing detail difficult.
When your vision is measured in the hospital eye clinic or by your optometrist (optician) you may also find that it is harder to read as far down the letter chart. Epiretinal membranes don’t affect peripheral (side) vision so they do not lead to total loss of sight.
Why does ERM develop?
ERM is most common in people over the age of 50. It is thought that most epiretinal membranes occur because of another change in the eye called posterior vitreous detachment (PVD).
During this process, cells may be released and then multiply on the surface of the retina to form a sheet, which is known as an epiretinal membrane. As the numbers of these cells increase, the sheet can start to shrink and cause the retina to wrinkle.
If the cause of an epiretinal membrane is unknown, not caused by PVD or another condition it is referred to as “idiopathic”.
ERM can also be associated with other eye conditions or because of previous eye surgery. This is known as an epiretinal membrane secondary to another problem. Secondary epiretinal membranes most commonly develop after retinal detachment surgery but can also be caused by laser treatment for diabetic eye disease, treatment for retinal tears, conditions that cause changes to retinal blood vessels in the back of the eye, inflammation (swelling) in the eye and trauma. Secondary epiretinal membranes tend to affect vision more than idiopathic ERM, or ERM caused by PVD.
Could I develop ERM in the other eye?
Most epiretinal membranes affect only one eye. About 10 per cent of idiopathic epiretinal membranes affect both eyes. This means that most people who have an epiretinal membrane will not go on to develop one in the other eye.
If you have an epiretinal membrane secondary to another condition, whether you will develop one in the other eye will depend on if the cause of the membrane is also present in this eye. Your ophthalmologist would be able to explore with you whether you are at risk of developing an epiretinal membrane in your other eye.
Is there anything I can do to avoid or improve ERM?
There is nothing you can do to avoid getting ERM. Diet and exercise haven’t been found to have any link with the development of ERM. Having an eye test at least every two years is the best way to make sure your eyes are healthy and that no new eye conditions are developing. There is nothing you can do to fix ERM yourself.
What treatment is available for ERM?
Surgery is the only treatment for ERM, there are no medications or other treatments that can improve or remove it. Surgery only needs to be considered if you are experiencing difficulties with your vision.
If your ERM is not causing any problems with your vision, or only affecting your vision slightly and you are managing OK, then your ophthalmologist may suggest just monitoring the membrane to see whether it worsens. Many people do not have any worsening of their ERM and may never need treatment.
If your vision is affecting your everyday activities, your ophthalmologist (hospital eye doctor) may recommend surgery. Surgery to remove an epiretinal membrane involves a procedure called a vitrectomy. This involves the ophthalmologist making tiny cuts in your eye and inserting fine instruments to gently remove the vitreous gel from the middle of your eye. Your surgeon will then grasp and gently peel away the epiretinal membrane from the retina.
Should I have surgery?
There is no wrong or right time to have epiretinal membrane surgery. Some people may choose not to have surgery and to accept the distorted vision in one eye. If you have good vision in the other eye, over time you will adapt to the distorted vision in the affected eye, and this may no longer bother you.
If ERM is left untreated, it will not cause any other problems in your eye.
How well does surgery work?
The main benefit of having surgery is that it usually improves or completely removes the distortion in your vision. Most people notice this improvement in the first month following surgery.
Approximately, 80 percent of people who have surgery to remove an epiretinal membrane also have an improvement in their level of vision (how much of the letter chart they can read).
It can take about two to three months after surgery for the extent of this improvement to be seen, although your vision may continue to get better for up to 6-12 months before the final level of vision is known.
How well your vision is likely to recover after surgery can depend on several things, including how affected your vision was before the surgery, how long your vision has been affected for, whether there are any complications resulting from the surgery, as well as if the membrane is idiopathic or secondary to another condition.
Your ophthalmologist will be able to give you an idea of how much improvement you are likely to get to help you decide whether having surgery is the right choice for you.
Further help and support
It’s completely natural to be concerned when you’ve been diagnosed with ERM. We’re here to support you every step of the way, and to answer any questions you may have – just get in touch with our Sight Loss Advice Service.
Page last reviewed: Sept. 1, 2022
Next review due: Jan. 31, 2023