Treatment of Diabetic Retinopathy
Good control of diabetic disease produces many benefits, including slowing down the development of retinal complications, kidney complications and foot neuropathy. Therefore, it is very important to control your diabetes. Complications of diabetic retinopathy are commonly treated with laser therapies, medication and eye surgery.
As demonstrated in the Diabetic Retinopathy Study (DRS) and The Early Treatment Diabetic Retinopathy Study (ETDRS), laser therapies can be extremely useful in reducing the rate of visual loss. Laser treatments for either macular swelling or new blood vessels are performed as an outpatient with topical anesthetic drops. Treatments may be divided into several sessions over a few weeks, depending on what needs to be treated. Although some patients may want a family member or friend to help them with transportation, most patients can handle the treatments easily and without pain.
Macular/focal laser for macular swelling. This treatment is applied to stop or reduce the leakage in the macula. The laser treatment is usually completed in one session, and depending on the patient’s response, additional macular laser may be applied several months later. Although laser treatment can slow the progression of diabetic retinopathy, its goal is to stabilize vision rather than to reverse any visual loss. Patients are often reminded that this is why we emphasize early detection followed by early treatment.
Panretinal/scatter laser for reverse blood vessel development. This treatment is applied to eyes and the goal is to shrink the new blood vessels. A total of 1,400 to 1,600 spots are applied and often the treatment is split into at least two sessions. As the vessels begin to shrink, small bleedings may occur from traction on the vessels, but without this laser treatment, severe bleedings often occur as part of the natural course of this disease. Increased macular leakage may also develop after scatter laser, but again, the benefit of the scatter laser treatment outweighs some of the laser-associated complications.
In recent years, many drugs have been studied for the management of diabetic retinopathy. No systemic medications (pills or intravenous infusions) are used to treat the condition. Butseveral medications that are injected into the eye have been shown to be effective and are FDA approved for the management of both diabetic macular edema (swelling of the central part of the retina) and proliferative diabetic retinopathy (the growth of new, fragile, blood vessels on the retina).
These eye injections are usually painless. You may experience some mild-to-moderate discomfort after the injection from the antiseptic drops that are put in the eye before the injection. Most patients tolerate repeated injections very well, with only minor discomfort.
There are two classes of diabetic retinopathy medications:
Anti-VEGF agents: These medications block the action of a chemical called vascular endothelial growth factor (VEGF), which is responsible for new blood vessel growth and leakage of fluid from damaged blood vessels in patients with diabetic retinopathy. These agents, which are injected into the eyes, are very effective at reducing swelling and improving vision in patients with macular edema. They also effectively reduce the risk of severe vision loss in patients with neovascularization (new blood vessel growth).
Avastin is the most commonly used anti-VEGF agent due to its lower price, but it is not FDA-approved for treatment of eye disease. Its use is “off label.” Two FDA-approved anti-VEGF agents, known as Lucentis and Eylea, are also available. All three of these medications work very well but require frequent injections usually for several years. Health risks linked to anti-VEGF injections are very low. The main worry is possible infection, which occurs in about one in 4,000 injections. Unlike steroid injections, there is minimal risk of cataract formation or glaucoma.
Steroids: These include triamcinolone acetonide, dexamethasone, and fluorocinolone. All three steroids are injected directly inside the eye to reduce macular swelling. They can be very effective, and in some patients, can significantly improve vision. Depending on the type of formulation, these medications are effective from a few months to even a few years.
Unfortunately, intraocular steroid use is associated with a substantial risk of glaucoma and cataracts. For this reason, steroids are typically reserved for treatment of eyes that have already had cataract surgery and that have shown only a modest or short-term response to anti-VEGF medications.
Vitreous surgery for diabetic retinopathy is surgery within the eye in order to remove blood, re-attach the retina, or both. The procedure is usually done under local anesthesia, similar to modern cataract surgery. Miniaturized instruments such as scissors, lasers, and other devices are introduced into tiny openings in the side of the eye. Thanks to new technology, with either 23-gauge or 25-gauge instrumentations, we are able to perform vitrectomies much faster than before.
Can you use Aspirin?
There are no ocular contraindications/restrictions on the use of aspirin when required for cardiovascular disease or other medical conditions. The Early Treatment Diabetic Retinopathy Study showed that aspirin had no effect on retinopathy – no harmful or beneficial effects.