Epretinal Membrane (ERM)

Epiretinal Membrane (ERM) are a frequent finding by an Optometrist, particularly in older patients. An Epiretinal Membrane (ERM) is a semi-translucent thin layer of fibrous tissue consisting of naturally occurring cells that can develop on the surface or above the surface of the macula and can result in issues with central vision such as decreased vision and/or metamorphopsia which is a visual defect that leads to linear objects looking curved. Most Epiretinal Membranes occur because the vitreous (the gel-like fluid inside the eye which fills the space between the lens and the retina) pulls away from the retina. Epiretinal Membrane most commonly occurs in patients over the age of 50, it may happen following eye surgery or as a result of inflammation within the eye. An Epiretinal Membrane (ERM) is commonly described as scar tissue on the retina, other names for an ERM include a macular pucker or cellophane maculopathy. Epiretinal Membrane (ERM) may impair vision if the layer of cells begins to shrink, allowing the retina to wrinkle up beneath it, resulting in blurred and distorted vision. An Epiretinal Membrane (ERM) does not lead to complete sight loss as it does not impair peripheral vision. In some cases, Epiretinal Membrane (ERM) does not cause vision problems or surgical intervention, but does require monitoring to see if the ERM progresses, may ERMs do not worsen and may never require medical intervention.

It is thought that most ERMs occur following a change in the eye known as Posterior Vitreous Detachment (PVD), this is a condition in which the vitreous pulls away from the retina at inferior of the eye, this is as a result of the vitreous gel becoming more watery with aging, which causes the eye to have difficulty withholding it's shape. A Posterior Vitreous Detachment is painless and it does not result in sight loss, but the patient may experience floaters (small dark spots in vision) and flashing lights, these symptoms mimic a more serious condition called Retinal Detachment which requires immediate medical treatment.