An epiretinal membrane (ERM) is a thin, scar-like layer of tissue that forms on the surface of the retina, specifically over the macula. The macula is a small area within the retina responsible for sharp, central vision, which is used for tasks like reading and recognizing faces. This membrane can contract and wrinkle the macula, leading to distorted or blurred vision. An epiretinal membrane peel is a specialized surgical procedure designed to carefully remove this abnormal tissue from the retinal surface.
When an Epiretinal Membrane Peel is Recommended
An epiretinal membrane peel is recommended when symptoms significantly affect a patient’s daily life. Common symptoms include blurred vision, distorted vision (metamorphopsia), where straight lines may appear wavy or crooked, and sometimes double vision in one eye. These visual disturbances can interfere with activities such as reading, driving, or recognizing fine details.
Diagnosis of an ERM occurs during a routine eye examination, where the ophthalmologist can observe the membrane on the retinal surface. Optical Coherence Tomography (OCT) scanning is a key diagnostic tool. OCT uses light waves to create detailed cross-sectional images of the retina, allowing the doctor to visualize the membrane, assess its thickness, and determine how it affects the underlying retinal layers. Surgery is considered when the OCT scan confirms significant traction or distortion of the macula, correlating with the patient’s reported visual impairment.
The Surgical Process
An epiretinal membrane peel is performed as part of a procedure called a vitrectomy. This surgery usually takes less than an hour and is often done on an outpatient basis. Anesthesia is typically local, numbing the eye while the patient remains awake, though mild sedation can be given for comfort.
During the vitrectomy, the surgeon makes small incisions, usually about 1 millimeter in length, in the white part of the eye, called the sclera. Through these tiny openings, microscopic instruments are inserted into the eye. The vitreous gel, a clear, jelly-like substance that fills the center of the eye, is then carefully removed. Removing the vitreous allows the surgeon direct access to the surface of the retina. The eye will naturally refill with a sterile saline solution or other natural fluid.
Once the vitreous is removed, the surgeon uses fine forceps to peel the epiretinal membrane from the macula. In some cases, the internal limiting membrane (ILM), the innermost layer of the retina, may also be peeled. This additional step can help reduce the risk of the ERM recurring. The small incisions made during the procedure are often self-sealing and typically do not require stitches.
What to Expect During Recovery
Immediately after surgery, an eye patch or shield is placed over the operated eye, which should be worn for the first 24 hours. Patients are advised to wear an eye shield at bedtime for two weeks to protect the eye from accidental rubbing. Mild discomfort is common, and over-the-counter pain relievers like acetaminophen are sufficient to manage it. Aspirin or ibuprofen should be avoided as they can increase the risk of bleeding.
Prescribed eye drops, typically antibiotics and anti-inflammatory medications, are used for several weeks, often for up to a month or six weeks, to prevent infection and reduce inflammation. Activity restrictions usually include avoiding heavy lifting (over 5-10 pounds), bending at the waist, and rubbing the eye for at least one week. Swimming should be avoided for a few weeks to a month to prevent infection. Vision will likely be blurry immediately after surgery, and it will improve gradually over time.
Vision Improvement and Potential Considerations
Visual improvement after an epiretinal membrane peel is gradual and can continue for several months, often for up to 3 to 6 months, and sometimes even up to a year. The primary goal of the surgery is to reduce visual distortion and stabilize vision, rather than to achieve a complete return to pre-condition acuity. While many patients experience significant improvement, some mild residual symptoms may persist.
A common consideration following vitrectomy for ERM is an increased risk of cataract formation or progression, particularly if the natural lens is still present. Other potential considerations include retinal detachment or infection (endophthalmitis). Patients should contact their doctor immediately if they experience severe pain, sudden loss of vision, increased redness, flashes of light, new floaters, or a spreading shadow in their vision.