What are epiretinal membranes?
Epiretinal membranes (also known as macular pucker or cellophane maculopathy) are fine membranes that grow on the surface of your retina. This membrane can distort and contort retinal structures resulting in vision being blurred and distorted.
Who gets it?
Men and women are equally affected by the condition which is more common over the age of 60. Incidence continues to rise with age with estimates saying 20% of all people over age 75 years have a degree of it though the vast majority will be visually insignificant.
What causes it?
In most cases, no cause is identified but occasionally, it can be linked with posterior vitreous detachment, previous retinal laser treatment, retinal tears, retinal vascular occlusions, inflammation, injury and usage of cryotherapy.
What are the symptoms?
Majority of epiretinal membranes are mild and hence patients are relatively asymptomatic. However, as it grows it can affect the structure of the retina resulting in blurred and distorted vision of variable degree. Patients may also complain of differences in size of objects between both eyes.
How is it treated?
Treatment for epiretinal membrane is surgical but varies according the severity of the membrane and also the degree of patient symptoms. If patients have no significant complaints and are coping well with their vision, then surgery is not recommended as it will not improve their vision associated quality of life. However, if patients are symptomatic, then a choice is usually made between observation or surgery. This will be discussed with you during your initial consultation.
What does surgery involve?
Surgery for epiretinal membrane involves mechanically peeling away the membrane from the surface of the retina. In order to gain access to the membrane, the vitreous part of the eye (the gel that fills the cavity at the back of the eye) is removed in a procedure called vitrectomy. Vitrectomy is performed using three “keyhole” incisions of around 0.5mm each in the eye. After removal of the vitreous gel, the epiretinal membrane is peeled off the retina using micro-forceps. Finally, the peripheral retina is searched for any retinal tears. If retinal tear(s) are found in the periphery (usually in about 5% of cases), they are treated (with laser or cryotherapy), and a gas bubble is placed in the eye. Otherwise, no gas bubble is placed in the eye. The surgery can be done under local anaesthetic (where the patient is awake) or general anaesthetic (where the patient is asleep). The surgery usually takes approximately one hour to perform. If there is a signifcant cataract in the same eye as the epiretinal membrane, this can be removed at the same time.
How successful is surgery?
Surgery is done with the primary aim of stabilizing vision and any improvement is regarded as a bonus. However, vast majority of patients (up to 80%) notice their vision and distortion to improve gradually over the course of 6 to 9 months. Vision does not however reach the levels prior to the development of the epiretinal membrane despite surgery.
What happens if no surgery is undertaken?
As mentioned above, most epiretinal membranes are mild and only 10-20% of patients progress to require surgical intervention. However, if left untreated, vision will remain blurred and/or distorted in the affected eye and might worsen over time. If it does, then any surgery is unlikely to help regain the loss.