Epiretinal Membrane
An epiretinal membrane is a layer of tissue that grows on the surface of the macula (the central area of the retina).
It can contract, thicken, and pull on the retina, causing folds and macular edema (fluid accumulation). These changes are responsible for the symptoms.
The prevalence in people over 50 years of age ranges from 7% to 11.8%.
In 20–30% of cases, it can be bilateral.
Causes
- Unknown origin (idiopathic): These account for the majority of cases.
- Secondary causes: Associated with conditions that involve vitreous inflammation, such as uveitis, trauma, retinal detachment surgery, retinal vascular occlusions, cryotherapy, or peripheral retinal photocoagulation.
Symptoms
- Initially, there are usually no symptoms.
- As it progresses, it may cause distorted vision (metamorphopsia), changes in the perceived size of objects, double vision, differences in image size between the two eyes (aniseikonia), and decreased central visual acuity.
Diagnosis
A fundus examination allows the ophthalmologist to assess the extent of the membrane and the distortion of retinal blood vessels caused by it.
Optical coherence tomography (OCT) is the main method for diagnosis and follow-up.
Treatment
In the early stages, surgery is usually not necessary, and periodic monitoring with OCT is recommended.
Surgical treatment is indicated when there is visual loss and/or significant visual distortion.
The goal of surgery is to relieve the traction of the membrane on the macula. This involves performing a vitrectomy, removal of the epiretinal membrane, and peeling of the internal limiting membrane.
The prognosis depends on visual acuity prior to surgery, the duration of the condition, and the degree of retinal damage caused by the membrane.