Diabetic Eye Disease: Symptoms and Treatment
Leo Am Kim, MD, PhD
Diabetic eye disease refers to several eye problems that can develop with type 1 or type 2 diabetes. Eye problems develop after diabetes has been poorly controlled for years.
“Diabetic eye disease is a group of eye diseases. It’s primarily a complication of high blood sugar levels, which can eventually damage the blood vessels over time and lead to disease,” explains Leo Am Kim, MD, PhD, a Mass General Brigham ophthalmologist and retina specialist. Dr. Kim treats patients at Mass Eye and Ear and Massachusetts General Hospital.
Diabetic retinopathy
Retinopathy, the most common cause of vision loss in working-age adults, is a serious diabetic eye disease. It affects the retina, which sits at the back of your eye and sends visual information to your brain.
“The retina itself is part of the brain. It’s neural tissue,” says Dr. Kim. “When you get diabetic retinopathy, you have damage to that neural tissue.”
Earlier stages of the disease, called nonproliferative diabetic retinopathy (NPDR), range from mild to severe. The most advanced stage, called proliferative diabetic retinopathy (PDR), causes abnormal blood vessels to grow (proliferate) on your retina.
These abnormal blood vessels can bleed and fill your eye with blood. They can also form scar tissue that can pull your retina off the back of your eye. PDR puts you at risk for permanent vision loss.
“If you control your diabetes and you get treated properly, there is some potential to improve retinopathy,” says Dr. Kim. But, in general, the disease will continue to worsen over time. The sooner you get treatment, the better your chances of preserving your vision.
Eye injections for diabetic retinopathy
Eye injections temporarily improve the leakiness of the abnormal blood vessels within the eye to prevent bleeding with PDR. These injections use a medication called anti-VEGF (anti-vascular endothelial growth factor).
“When the retina gets damaged, it sends out a signal saying, ‘I need some new blood vessels here because I’m not getting good blood flow.’ That signal is called VEGF,” explains Dr. Kim. Anti-VEGF drugs target that signal to stop new blood vessels from growing and decrease the leakiness of blood vessels.
Laser treatment for diabetic retinopathy
Dr. Kim prefers to use laser treatment in combination with anti-VEGF therapy for PDR, which offers a more permanent solution. Laser treatment uses a laser to treat retinal tissue receiving poor blood flow and decrease VEGF signaling.
It targets the periphery (sides) of your retina, where blood supply is poorest. While laser treatment causes you to lose some peripheral vision, it is meant to save your central vision.
Diabetic retinopathy surgery
“When you have blood that doesn’t clear from your eye, or a detached retina due to scar tissue, then you need surgery,” says Dr. Kim. Surgery removes blood, gently removes scar tissue from the retina, or reattaches the retina.
Diabetic macular edema
The macula (the center of the retina) allows you to see the center of your visual field. When blood vessels get damaged and become leaky, the macula swells and causes blurry vision. Macular edema, or swelling of the macula, can develop at any stage of retinopathy. It happens in about 50% of people with diabetic retinopathy.
Eye injections for macular edema
Eye specialists inject anti-VEGF or steroid medications to treat macular edema. You may get repeated anti-VEGF or steroid injections, or a combination of both.
“Anti-VEGF decreases leakiness of blood vessels and causes swelling to improve,” says Dr. Kim. Steroids also decrease swelling. “Patients can notice a difference within a couple of weeks.”
Glaucoma with diabetes
Glaucoma is when you have damage to the optic nerve, which connects your eye to your brain. It often occurs due to elevated pressure inside your eye. It slowly causes vision loss if left untreated.
Diabetes doubles your risk of developing open-angle glaucoma. Another type, called neovascular glaucoma, can happen from proliferative diabetic retinopathy. When abnormal blood vessels grow in the front part of your eye, they keep fluid from leaving your eye and increase eye pressure.
Glaucoma treatment
Eye specialists may recommend medicated eye drops, laser treatment, or glaucoma surgery. All these treatments can decrease fluid production within your eye or help fluid drain from your eye. This reduces eye pressure and keeps glaucoma from worsening.
Cataracts with diabetes
Cataracts are when the lens, which sits near the front of your eye, becomes cloudy. They cause blurry vision and make colors look faded. “This eye problem often happens with age, but poor blood sugar control can lead to cataracts earlier in life,” says Dr. Kim.
Cataract surgery
You may not need to take action early on, but eventually cataracts can significantly impair your vision. At that point, you can get cataract surgery. Cataract surgery replaces the cloudy lens in your eye with an artificial lens to improve your vision.
Diabetic eye disease symptoms
Your vision may look blurry, distorted, or hazy if you have diabetic eye disease. You may see “floaters,” or pieces of debris, if diabetic retinopathy causes bleeding in your eye. In severe cases, your vision may go completely black if your eye fills with blood.
Eye screening for diabetes
Early detection of eye diseases caused by diabetes can help prevent permanent vision loss. An ophthalmologist can check for and treat diabetic eye disease.
Your risk for diabetic eye disease, especially diabetic retinopathy, increases with:
- High blood pressure
- High cholesterol
- Pregnancy
Dr. Kim emphasizes the importance of seeing a retina specialist with advanced training in the back of the eye. He recommends seeing a retina specialist:
- Within 3 years of being diagnosed with type 1 diabetes
- As soon as you get diagnosed with type 2 diabetes
- Every trimester of pregnancy if you have diabetes in pregnancy
“With time, everybody with diabetes develops some form of diabetic retinopathy—even with the best control of the disease,” says Dr. Kim. “But if you control your diabetes, you have a lower risk of developing retinopathy earlier or having it worsen.”
