An Epiretinal Membrane is a condition where a very thin layer of scar tissue forms on the surface of the retina, where the vision is sharpest. The part of the eye affected by the Epiretinal Membrane is called the Macula, which is made of special nerve cells and it provides our sharp central vision needed for seeing fine detail (reading and driving etc.). When an Epiretinal Membrane forms over the Macula, it may contract and crumple up the Macula resulting in distorted and/or blurred vision.
In most cases the development of an Epiretinal Membrane appears to be related to normal aging changes inside the eye. In some cases it can be related to other conditions such as diabetes, blockage of blood vessel, inflammation or following retinal surgery. Epiretinal membranes are not related to Macular Degeneration. Epiretinal Membranes do not usually affect the other eye. They are quite common and affect up to 8% of people in later years.
Your eye doctor is able to detect an Epiretinal Membrane during an eye examination following the use of eye drops that temporarily make your pupils large. Sometimes, a special scan of the back of the eye may be needed to confirm the presence of an Epiretinal Membrane. Your eye doctor will assess your symptoms to help you decide whether to proceed with surgery.
In many cases, the discovery of an Epiretinal Membrane is by chance at a routine examination and the vision may not be affected. These Epiretinal Membranes tend not to change and do not always affect vision. Epiretinal membranes can occasionally get worse, causing blurring and/or distortion of vision. Treatment for Epiretinal Membrane is only required in those cases where the vision has been affected.
If an Epiretinal Membrane affects vision, the only way to treat it is to remove the membrane surgically. This is achieved by an operation called a Vitrectomy, where specialised instruments remove the jelly-like substance that normally fills the centre of the eye, called vitreous. The removal of the vitreous inside the eye does not cause any permanent harm, apart from speeding up the development of a cataract. The vitreous is replaced by natural fluid produced inside the eye. In some cases, the surgeon has to leave a special gas bubble inside the eye which disappears on its own after a few weeks.
The operation for Epiretinal membrane removal does not usually take longer than an hour and it can be performed using a local anaesthetic injection with the patient remaining comfortable and awake during the procedure. It is very important for the patient to stay still, especially during the very delicate manoeuvres when the membrane is removed using fine forceps.
Following membrane removal, the vision is typically more blurred and it can take months for it to improve. The operation is usually successful in reducing the distortion in vision due to an Epiretinal Membrane. If the vision had not been distorted prior to Epiretinal Membrane removal, improvement in the sharpness of vision and reading is less predictable.
Surgery for Epiretinal membrane removal speeds up the onset of cataract, which is a very treatable cause of worsening vision. Sometimes, an early cataract is removed at the same time as the membrane removal to spare the patient from cataract surgery in the near future. Epiretinal membrane removal carries the risk of 1 in 50 cases of ending up with significantly worse vision and 1 in 50 of requiring further surgery to deal with recurrent Epiretinal membrane or other complications of surgery such as retinal detachment. The risk of serious complications of Epiretinal membrane removal is about 1 in 1000 cases, where the eye becomes totally blind due to a bleed during surgery or an infection after surgery. Some patients may develop persistently high eye pressure, which can damage the nerve of the eye causing vision loss. This condition is called Glaucoma and can affect 1:100 patients following this type of surgery. It may require long term use of eye drops and sometimes glaucoma surgery in order to preserve vision.
Following surgery, you will be given eye drops to use for a few weeks, which will help the eye settle from surgery. The operation does not require staying in hospital longer than one night and patients are typically reviewed in clinic a couple of weeks after surgery. In some occasions, you may be asked to position your head in a certain way for some part of the day for a number of days. Otherwise, you can do most daily activities although you should abstain from unhygienic environments and anything that puts the eye at risk of injury.
Most people will need at least two weeks off work after surgery. The amount of time off work will depend on the kind of work you do and the kind of surgery that is done. This will need to be discussed with your surgeon.
The RNIB have further information, especially some practical advice: Helpline 0303 123 9999; internet www.rnib.org.uk; email helpline@rnib.org.uk
The Macular Disease Society: Helpline 0845 241 2041; internet www.maculardisease.org; email: info@maculardisease.org
The advice on this page is based on a variety of sources, including latest research published in peer-reviewed scientific journals. It has also been scrutinized by a panel of experts from the Britain & Eire Association of Vitreoretinal Surgeons (“BEAVRS”). If you require further information about this, please ask your surgeon.