The retina, similar to the photographic film itself, is a thin layer of tissue that lies against the back surface of the eye wall. Only the central portion of the retina, the macula, is sensitive enough to provide high quality vision for tasks such as reading, watching television, or driving. The macula is a very small area, with the central portion being only about the size of the head of a pin
What is epiretinal membrane?
In some conditions a thin layer forms on the macula. This thin layer of scar tissue is known as a macular pucker. Macular pucker is known by a variety of names, including epiretinal membrane, surface wrinkling retinopathy, cellophane retinopathy, and internal limiting membrane disease. All of these names relate to the fact that there is a layer of thin scar tissue on the surface of the macula which resulting in mechanical wrinkling and distortion of the retina.
In most patients, even with the formation of a significant macular pucker or epiretinal membrane, there is very slow growth that takes place, and eventually the scar tissue stops proliferating or extending. With time, contraction or pulling of the cells may take place, causing a wrinkled or rippled appearance to this scar tissue.
Since the scar cells are attached to the retina, the retina itself becomes wrinkled in association with the progression of the scar. When this occurs in the central, critical portion of vision, the macula, visual symptoms may result.
What are the symptoms due to epiretinal membrane?
The symptoms of a macular pucker are common to many conditions affecting the central part of the retina.
How do we diagnose the condition?
The diagnosis of a macular pucker is made when an ophthalmologist performs a dilated retinal examination and examines the back of the eye.
OCT helps us determine how much of thickening of the central portion (macula) has happened because of the membrane. A fluorescein angiogram (injection of a dye into the vein, with photographs taken of the back of the eye) may be recommended to evaluate the situation and determine if leakage or swelling of the retina is taking place as a result of the scar tissue being present on the surface of the macula.
How do we treat it?
In most cases, no treatment is recommended for macular pucker. This is due to the fact that the visual distortion and decreased reading and distance vision is minimal in the majority of patients. Although some mild visual problems are noted, these are usually easily adjusted to and pose no limitation on full activity. In some instances, however, the distortion and vision loss may be significant. There may be an inability to perform certain daily tasks such as reading or driving.It is at this point, that consideration for surgical repair would be entertained. Surgery would also be considered if vision loss is moderate, but there is evidence on the fluorescein angiogram of significant leakage posing a threat to permanent damage to central vision in those individuals. Repair of a macular pucker or epiretinal membrane is accomplished through use of vitreoretinal surgery.
Using microsurgical instruments, a procedure known as a vitrectomy, the microscopic removal of vitreous jell from the center of the eye, is performed. Specialized microsurgical instruments are then used to gently peal and remove the scar tissue from the surface of the retina, relieving the traction and reducing the distortion to the retinal surface. Unlike macular hole surgery, macular pucker surgery does not typically involve the use of an intraocular air bubble in most of the instances. As a result, no specialized positioning in the postoperative period is required. Full visual recovery may not occur for at least 3-4 months following the procedure.