Macular Pucker (Epi-retinal membrane)
A macular pucker (epi-retinal membrane) is a semi-translucent membrane that grows on the surface of the central retina (macula). Most cases have no identifiable cause. They are discovered in at least 2% of patients older than 50 years of age, and in 20% of patients older than 75 years old. Both genders are affected equally. Some cases are caused by previous eye injury, retinal vessel occlusions, retinal breaks, inflammation of the eye, and previous eye surgery or laser treatment.
The membrane consists of normal retinal cells that proliferate in an abnormal manner, creating a sheet that exerts traction on the retina and causes distortion of the normal layers. This distorted anatomy can result in symptoms of distorted vision.
Most cases can be monitored every 6 months without treatment. Patients whose primary complaint is distortion of the central vision are the best candidates for surgical repair. These patients often notice a bending of lines that otherwise should be straight, such as the edge of a door post or an Amsler grid.
Surgery involves pars plana vitrectomy (see procedures section above) and gentle membrane peeling with fine forceps under the microscope. Like most eye surgeries, it is an outpatient procedure with patients going home the same day. The eye will be covered with a patch for the evening, and the patch is removed the following day at the post-operative clinic visit. Steroid and antibiotic eye drops are used for one month.
Visual improvement of 2 lines or more is seen in approximately 60-80% of patients. Unlike cataract surgery or LASIK, where visual improvement is much more rapid; the process following ERM surgery requires 6-12 months before the final visual outcome is reached to allow time for the retinal layers to revert to a more normal configuration.
Like any other eye surgery, the majority of patients have a positive outcome without complications, but there are risks including but not limited to bleeding in or around the eye during the immediate or extended post-operative period, infection, cataract, retinal tear and retinal detachment.