Epiretinal membrane

What is epiretinal membrane?

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. 
Your retina is the light-sensitive layer that lines the back of the eye. 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. 
Our downloadable factsheet has more information about epiretinal membrane:

How does ERM affect vision?

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.
Not everyone who has an epiretinal membrane experiences problems their 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. 

What treatment is available for ERM? 

If the 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 may recommend a surgery called a “vitrectomy” to peel away the membrane. 
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. 
Surgery usually helps improve or completely remove the distortion, and for about three quarters of people also improves their level of vision.

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)
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. 
ERMs that have developed secondary to another problem or condition tend to affect vision more than ones that are idiopathic or caused by PVD.