What is an epiretinal membrane?
An epiretinal membrane is a translucent cellular membrane that develops over the macula (the central part of the retina responsible for vision of detail and movement). These cells are normally derived from the retina but may also be derived from deeper layers, such as the pigmented epithelium.
These cells secrete collagen and form a mesh; when this membrane contracts, it distorts retinal tissue, giving rise to folds and wrinkles on the surface of the macula that affect its function.
If the epiretinal membrane is not treated, it may lead to loss of central vision; however, it will never lead to total vision loss because only the macula is affected. Hence it is important to undergo annual reviews.
Symptoms of epiretinal membrane
This pathology may be asymptomatic, though the main symptoms that reveal the presence of an epiretinal membrane are loss of visual acuity, distortion of images (metamorphopsia), micropsia (seeing objects smaller), diplopia (seeing double), aniseiconia (seeing objects of different size in each eye) and vision loss.
Medical tests for epiretinal membrane
To confirm metamorphopsia, the Amsler grid test is performed. To diagnose blurred vision, optotypes are used.
What are the causes of epiretinal membrane?
There are different factors that can cause epiretinal membrane, though the most frequent is posterior vitreous detachment (ageing process of the gel inside the eye, usually appearing in people aged over 50 years). Other causes are retinal detachment, vascular diseases, intraocular inflammation and severe ocular traumatic injury.
Can it be prevented?
There are no concrete measures to prevent the development of an epiretinal membrane. Even so, it is important to consult with an ophthalmologist if you suspect any symptoms (such as floaters or flashes).
Treatment of the epiretinal membrane
The epiretinal membrane can be monitored at regular intervals, but if the symptoms worsen, consideration should be given to vitreoretinal surgery (posterior vitrectomy), one of the retinal surgical procedures giving the best results. This technique can restore vision that has been lost since the membrane developed (however normally only about half is restored, so the intervention should not be delayed too much).
Which specialist treats it?
The epiretinal membrane should be treated by an ophthalmologist.