Not seeing straight: epiretinal membrane

A person experiencing symptomatic epiretinal membrane will notice that their vision is being affected, and straight lines begin to appear bent or wavy. Mr Bataung Mokete, a highly-skilled consultant ophthalmologist with advanced subspecialty training in surgical diseases of the eye, explains why epiretinal membranes occur, who is affected, and when surgery should be performed.

Why does epiretinal membrane happen? 

The inside of the eye, lined with a retina, contains vitreous gel, a jelly-like substance. Over our lifetime, this gel starts to degenerate, breaking up, and eventually, it will separate from the back of the eye. In this process, tissues or cells that normally aren’t near the retina can find their way onto its surface. Sometimes they will just settle and not cause any problems, but other times they proliferate and form a sheet called a membrane. This is quite common over the age of about 50, lots of people have these membranes but, in most cases, they are subtle and don’t cause any symptoms at all.

What are the stages? 

The membranes proliferate, they may just say as just a sheet and not cause any problems for patients. Occasionally that sheet gets thicker and, importantly, contracts. If the sheet contracts, the retina, which is usually nice and smooth, becomes uneven, or wrinkled. Imagine the retina as the film in a camera, if it is wrinkled, the image will fall on an uneven surface and be distorted. This is the main symptom that patients have.This distortion may progress to the point where the vision is very blurred, although most people will present before that point.

When is operating necessary for an epiretinal membrane? 

Operation is necessary when the membrane is causing symptoms, mainly distortion like when patients look at straight lines and the lines appear wavy to them. Other surfaces like window frames, door frames, or lines on the road will also be distorted. This can affect one’s ability to work, for example, if someone works with spreadsheets or objects with lines. It can also affect confidence when driving, and other everyday activities like going up the stairs.

Will it go away on its own or heal itself? 

Membranes, in the vast majority of people, develop and do not progress. In these cases, the membrane is not symptomatic, it’s not a clinical issue, nor is any action required. If symptomatic, some will progress, up to about 28%, causing problems or symptoms for patients. In a small number of patients, when the jelly eventually separates from the back of the eye, it can result in the membrane coming off with the jelly which relieves symptoms.

How is epiretinal membrane treated surgically? 

Treatment for people who have symptoms is an operation called a vitrectomy. This procedure involves making three ports (holes) in the white of the eye, preformed under anaesthetic, so that the jelly inside the eye can be removed to allow access to the back of the eye. A special dye is then used to dye the membrane blue which makes it easier to peel away, ensuring as much as possible is removed, in order for the operation to be a success. The operation takes about 30 to 45 minutes if no other procedures are involved. Although normally done under local anaesthetic, general anaesthesia is available as an option. It is very successful at relieving symptoms. Relief of symptoms is sometimes not immediate, as although the membrane is removed, the retina may remain crinkled for some time, but the creases will fall out naturally to assume the normal shape. This process can take up to a year and the main determinants of success are how long the membrane has been present, how severe the distortion is, and the age of the patient, as the older we get out tissues become less pliable or elastic making it harder for them to return a flat position.

If you are experiencing any of the symptoms discussed, you can book a consultation with Mr Bataung Mokete directly by visiting his Top Doctor’s profile.