When the doctor says you have age-related macular degeneration, or AMD, you might not think to manage the disease will involve surgery. The chronic eye condition is typically treated with vitamin supplements or with medications that are injected into the eye, depending on the type of AMD.
In rare cases, however, macular degeneration surgery may be performed.
What Is Macular Degeneration?
AMD affects the macula, the part of the eye that gives us central vision and helps us focus on objects such as faces or TV screens.
The macula is part of the retina, a thin layer of tissue in the back of the eye that takes images we see and sends them via the optic nerve to the brain.
Sometimes the macula can deteriorate and eventually stop working, causing central vision loss. This condition is called AMD and includes two types:
Wet AMD. In wet AMD – which makes up about 10% of AMD cases – new abnormal blood vessels grow behind the retina and leak. Blood and other fluids seep into the retina, causing the macula to bulge and stop working properly. Most vision loss from AMD is the result of wet AMD.
Dry AMD. In dry AMD – which makes up about 90% of cases – small deposits of cell debris called drusen appear between the layers of the retina. As drusen accumulate, they split the macular layers apart and cause them to become dry and thin, which can result in mild or significant vision loss. An advanced case of dry AMD is called geographic atrophy. Dry AMD sometimes progresses to wet AMD.
Treatment for AMD depends on your diagnosis.
The mainstay of wet AMD treatment is eye injections of anti-vascular endothelial growth factor drugs such as bevacizumab (Avastin), ranibizumab (Lucentis) or aflibercept (Eylea). The medications help stop abnormal blood vessels from leaking and reduce the number of abnormal blood vessels in the eye. Treatments are given monthly or as needed.
There are little doctors who can do for dry AMD but prescribe a formulation of vitamins and nutrients (known as AREDS2) that contains lutein, zeaxanthin, zinc, copper and vitamins C and E. AREDS2 has been shown to reduce the risk for developing wet AMD by 25%.
“Geographic atrophy involving the center of the macula is arguably the most unmet need in the treatment of macular degeneration. Patients report trouble reading, trouble functioning in dim environments and seeing blind spots or scotomas that slowly enlarge,” notes Dr. Aleksandra Rachitskaya, an ophthalmologist and retina specialist with Cleveland Clinic.
Wet Macular Degeneration Surgery
The standard of care for wet AMD once involved laser photocoagulation, an office procedure sometimes referred to as laser surgery. It focuses a thermal (hot) laser on a bleeding vessel in the back of the eye to burn and seal it. “But that’s gone by the wayside as a standard treatment and now is rarely used,” says Dr. Elliott Sohn, an ophthalmologist, researcher and retina specialist with the University of Iowa Carver College of Medicine.
The problem, Sohn explains, is that the laser causes vision loss. “Wherever you put the laser burn, the patient can’t see there anymore. You can imagine that’s the last thing patients will want when they’ve already lost central vision,” Sohn says.
But there are rare cases when laser photocoagulation is used today. “I might do one procedure every other year. We may consider it if there is a bleed in the back of the eye that’s not close to the center of vision and isn’t drying up with injections. Or maybe the patient can’t come back for eye injections every four to six weeks, and we can stop the bleed in one treatment,” Sohn says.
What about the risk of laser damage? “If it’s not near the center of vision, the patient shouldn’t notice it,” Sohn says. “However, a small percentage of eyes can have a recurrence of the bleed or develop a new lesion at the edge of the laser treatment.”
Another type of wet macular degeneration surgery used to close off leaky blood vessels is a laser procedure called photodynamic therapy, or PDT. It involves a cold or infrared laser that doctors use to activate a medication (given intravenously) called verteporfin (Visudyne). This procedure is also rare and has some risks. “A small number of patients can develop a loss of cells in the area that’s treated,” Sohn says. “We reserve this for patients who have wet macular degeneration that is resistant to the injections and continued fluid in the retina. I probably do five to 10 PDT procedures per year.”
Dry Macular Degeneration Surgery
The only macular degeneration surgery for people with dry AMD is for certain cases of geographic atrophy.
Doctors can remove the eye’s natural lens and implant a pea-sized, FDA-approved telescope behind the eye’s iris. “It is designed to enlarge retinal images of the central visual field and focus them onto healthy areas of the retina not affected by AMD,” Rachitskaya points out.
In other words, the device enables patients to use central vision in the affected eye to see close-up images. But the telescope may lead to side effects such as decreased peripheral vision, swelling of the cornea, double vision or infection.
The device implantation is also a rare surgery. The device maker notes that the tiny telescope has been implanted in more than 600 patients. It was approved by the FDA in 2010.
What to Expect for Macular Degeneration Surgery
How you prepare for macular degeneration surgery depends on the procedure.
For a thermal or cold laser procedure, you won’t have to fast or stop taking your medications. When you get to your doctor’s office, you’ll receive eye drops to dilate and numb your eyes. For either procedure, the doctor will place a special contact lens on your eye, and you’ll rest your head on a piece of equipment that looks like the machine used for eye exams. Then a laser will be used on the eye. Both procedures are quick and don’t require special eyedrops afterward.
The surgery to implant the telescope device is an outpatient procedure, similar to cataract surgery. You may need to avoid food or drink before the surgery. During the procedure, your eyes will be numbed and you’ll remain awake, but you won’t feel pain. Afterward, you’ll need to go on a course of special eyedrops to prevent infection and reduce redness and burning. You’ll also need to work with a vision rehabilitation specialist to learn how to use the device.
These procedures may or may not help your AMD. But take heart: New treatments and procedures are in the works.
Rachitskaya points to studies of medications that may play a role in halting geographic atrophy. “Moreover, in the realm of wet macular degeneration, there are promising early results from trials studying drug-delivery eye implants. The slow release of the medications over a prolonged period of time could result in fewer injections,” Rachitskaya says.
Sohn is optimistic that there may be new options for patients in the next few years.
“We are trying to look for treatments that will reduce the injection burden on patients and their families,” Sohn says. “This is a high priority for us in the field of macular degeneration research.”
Copyright 2019 U.S. News & World Report