Epiretinal membrane (ERM)
What an epiretinal membrane is, whether treatment is needed, and what surgery involves.
What is an epiretinal membrane?
An epiretinal membrane is a condition where a very thin layer of scar tissue forms on the surface of the macula — the central retina responsible for clear, detailed vision. When it contracts, it can crumple the macular retina, causing distorted and blurred vision.
In most cases this is related to normal ageing changes inside the eye, though it can also follow diabetes, vein occlusion, inflammation, or previous retinal surgery. Epiretinal membranes are not related to macular degeneration, do not usually affect the other eye, and are quite common — affecting up to 8% of people in later years.
Do I need treatment?
Many epiretinal membranes are discovered by chance at a routine examination and may not change or affect vision. Treatment is only required when the membrane affects your vision, and your symptoms help decide whether and when to proceed with surgery.
Surgery: vitrectomy and membrane peel
If an epiretinal membrane affects vision, the only treatment is surgical removal. This is achieved by a vitrectomy and epiretinal membrane peel, where specialised instruments remove the vitreous, and the membrane is carefully peeled off the retinal surface using fine forceps.
The operation takes about an hour and can be performed under local or general anaesthetic. Vision is typically blurred afterwards and can take some months to improve. Distortion usually improves sooner than overall sharpness.
Most people need at least two weeks off work.