Scar tissue can grow on the surface of the retina, directly over the macula. This scar tissue can contract, and cause the retina to wrinkle. The scar tissue on the surface of the retina is called an “epiretinal membrane” or “macular pucker”. An epiretinal membrane can cause visual loss, as well as distorted or double vision.
Epiretinal membranes may be caused by a variety of eye problems. They may follow retinal detachment surgery, laser treatment or cryotherapy for retinal tears. They may be associated with retinal blood vessel problems. In most cases, the epiretinal membrane occurs in an otherwise healthy eye as a result of a posterior vitreous detachment.
Your ophthalmologist may perform a test called a fluorescein angiogram. This diagnostic procedure utilizes a specialized fundus camera to capture rapid-sequence photographs of the retinal vasculature following an intravenous injection of fluorescein sodium. Another diagnostic test called Optical Coherence Tomography (OCT) may be performed. This test has the ability to generate cross sectional images of the retina.
The only treatment of visual loss caused by an epiretinal membrane is surgery to remove the membrane. If the visual loss or distortion is significant, a vitrectomy may be performed to remove the membrane. This surgery is usually performed under local anesthesia, The membrane is picked up with a fine instrument and gently peeled off the surface of the retina.
Vision usually improves slowly after surgery, with most of the improvement coming within the first three months, though it may continue to improve for many months. In some cases, the vision may not improve at all. The chance that vision will improve following surgery is about 85%. On an average, patients regain approximately half of the vision that was lost because of the epiretinal membrane.
The complications of surgery include retinal tears and detachment, cataract formation, infection, and regrowth of the membrane. These complications may result in mild to total loss of vision, although vision-losing complications are rare.