A macular pucker, or epiretinal membrane, is a piece of scar tissue that forms on the surface of your macula, the central part of the retina devoted to your central vision. This usually occurs spontaneously with age, though it may be related to diabetes or intraocular inflammation. The macular pucker can cause painless loss of central vision. Patients usually complain of a blurry spot in their central vision or distortion or wavy lines. Macular puckers can be fixed with a vitrectomy, a surgery that is performed by a retina specialist in the operating room. Surgical intervention may lead to a gradual improvement in central vision and a decrease in distortion.