Epiretinal membrane

It is a layer of scar tissue on the retina. The retina is the lining of the back of the eye responsible for your vision. Epiretinal membranes occur on the macula, which is the part of the retina responsible for fine vision (reading, watching TV, and recognising faces).

What are the symptoms?

In the early stages, not all epiretinal membranes will affect your vision. However, if they grow thicker they may cause the following symptoms:

1. Distortion of vision – straight objects (e.g. a door frame) may appear wavy. This is more noticeable when you close your other eye.
2. Blurring of central vision.

Why does an epiretinal membrane affect your vision?

Like scar tissue anywhere else in the body, epiretinal membranes can contract. This affects the function of the retina by:

1. Causing distortion of the retina.
2. Reducing the amount of light reaching the retina.
3. Causing blood vessels in the retina to leak and the retina to become swollen.

How is an epiretinal membrane diagnosed?

It has a typical appearance which can be diagnosed during an eye examination. The following tests may be needed to provide information about the cause and prognosis: 

1. Photographs of the retina.
2. Optical coherence tomography scanning of the retina.
3. Fluorescein angiography. 

What causes an epiretinal membrane?

In most people the cause is unknown. Occasionally, they can be caused by eye conditions such as retinal detachment, inflammation, retinal vein occlusion, trauma and previous eye surgery. A thorough eye examination by a retinal specialist should be performed to detect any other eye conditions which may need treatment. 

Is treatment needed?

Not all epiretinal membranes need treatment, however many patients benefit from surgery to improve vision or prevent further loss of vision.

A retinal specialist can help you decide if treatment is right for you. This will depend on many factors including your level of vision, whether you have other eye conditions, and your own preference.

What is the treatment?

The only treatment is epiretinal membrane surgery. This is highly specialised and only performed by eye surgeons with training in Vitreoretinal surgery.

 Depending upon your own preference, the surgery can be performed using local anaesthesia (so that you stay awake) or general anaesthesia (in which you are asleep during the operation).

The operation is not painful and usually takes under 1 hour. It involves keyhole surgery using tiny openings made in the eye. The jelly within the eye (called the vitreous) is removed and the epiretinal membrane is gently separated from the retina.

Dr Chen performs epiretinal membrane surgery using a state of the art technique called sutureless vitrectomy. This involves creation of smaller surgical openings than traditional techniques. This means that in most cases, no stitches are required. This leads to better post-operative comfort and a faster recovery.

Benefits and risks of surgery

The benefits of surgery may include:

1. Improvement in visual distortion.
2. Improved clarity of vision.
3. Prevention of further visual loss.

Most patients will develop a cataract within a few years of surgery and need a cataract operation. The risks of surgery include infection or bleeding inside the eye (less than 1 in 1000), retinal detachment (2%), and retinal swelling. Most complications can be treated with further surgery but some may lead to loss of vision.

Depending upon your individual circumstances, additional techniques may be required during surgery to reduce the risk of complications. These include:

1. Retinal laser treatment or cryotherapy to reduce the risk of retinal detachment.
2. Placing a bubble of gas inside the eye to prevent a retinal detachment.
3. Placing steroids inside the eye to reduce inflammation.

After surgery

You can go home after the surgery and do not need to stay in hospital overnight. Your vision should gradually improve. Epiretinal membranes cause distortion of the retina which takes up to 12 months to heal after surgery. Although 90% of patients will have improved vision after surgery, this may not happen if the epiretinal membrane has caused permanent retinal damage.

Dr Simon Chen

Dr Simon Chen explains epiretinal membranes.

Click on image to view video

Dr Chen talks about advances in retinal surgery.

Click on image to view video