Macular pucker, also referred to as epiretinal membrane, is a condition in which a thin, membranous tissue grows over the surface of the retina. Contraction of this membrane or ‘scar tissue’ causes wrinkling of the retina and may result in subsequent swelling of the retina (macular edema). Just as one would prefer to view a movie on a flat, smooth movie screen, clear vision depends on a smooth retina to accurately receive visual information from our environment. Wrinkling of the retina results in distorted images, while swelling of the retina produces blurred vision. Macular pucker typically occurs in those over age 50, and there is a slightly higher incidence in females.
In most cases, the cause is unknown but predisposing conditions include retinal vascular disease (e.g. diabetic retinopathy), retinal tear, prior retinal detachment, and uveitis (ocular inflammation). The condition is mild in most cases and affects both eyes in approximately 25% of cases.
Most epiretinal membranes are clinically insignificant and produce no symptoms or very mild visual disturbances. These membranes are often discovered on routine eye examination and present with a glistening or subtle sheen on the retinal surface. No treatment other than periodic monitoring is required, as approximately 70% of these will remain stable without intervention. When macular pucker starts to cause symptoms, the membrane is more clearly visualized on the surface of the retina. Definite wrinkling or striate of the retina are observed; the retinal blood vessels appear tortuous where the membrane is contracting and straightened or stretched in the surrounding areas. This produces symptoms of varying degrees of distortion depending upon the degree and location of traction induced by the epiretinal membrane. Careful examination will often reveal retinal swelling, or macular edema, which is responsible for blurred vision. Patients often describe their condition as ‘looking through a fish tank.’