An epiretinal membrane is a thin layer of scar tissue that lies on the surface of the central macula. It has many synonyms including macular pucker, cellophane retinopathy, and preretinal fibrosis. The scar tissue arises from a residue of the vitreous gel after it separates from the retina with age called posterior vitreous detachment. Epiretinal membranes are very common, but most of the time they do not cause any significant visual problems.
In some cases, and epiretinal membrane can be thicker and more severe. This can lead to significant visual symptoms, including blurriness and distortion in the central vision. In this case, the membrane causes significant contraction/distortion of the macula along with swelling. Typically, the membrane develops over several months, but it can stabilize after the initial growth phase and remain unchanged for many years.
The treatment for an epiretinal membrane is vitrectomy surgery to physically peel the scar tissue from the macula. The decision on surgery depends on many factors, including the level of symptoms, how long the membrane has been there, and the status of the other eye. The visual recovery after surgery is variable with residual distortion and blurriness very commonly seen, but most patients note a significant improvement in function. Improvement takes several months at least, sometimes up to a year.