Diabetic retinopathy is an eye condition that can develop if you have type 1 or type 2 diabetes. It’s caused by damage to a part of your eye called the retina, which is important for vision.
While you may start out with only mild vision problems, some people can eventually lose their eyesight. But the good news is that vision loss from diabetic retinopathy is often preventable.
The retina is the tissue that lines the back of your eye. Signals sent from the retina to the brain allow you to see. Diabetes affects the retina when high blood sugar levels cause damage to its blood vessels.
Diabetic retinopathy is the most common cause of preventable blindness in the United States, according to the American Diabetes Association. It’s also the most common eye disease in people with diabetes.
If you have diabetes, it’s important to get regular exams from an eye doctor. With early diagnosis and treatment, it’s possible to stop complications before they happen.
There are four stages of diabetic neuropathy.
Stages 1 to 3: Nonproliferative diabetic retinopathy
Together, the first 3 stages are known as nonproliferative diabetic retinopathy (sometimes shortened to NPDR). It’s called “nonproliferative” because the eye doesn’t make new blood vessels during the early stages of diabetic retinopathy. Nonproliferative retinopathy is also known as background retinopathy.
During the early stages of retinopathy, you might not notice problems with your vision, but your eye doctor will usually be able to detect changes to your retina.
There are 3 nonproliferative stages of retinopathy:
- Stage 1: Mild nonproliferative retinopathy. Tiny blood vessels in the retina swell, and some may start to leak.
- Stage 2: Moderate nonproliferative retinopathy. Blockages begin in some blood vessels. Usually, there’s leakage from blood vessels.
- Stage 3: Severe nonproliferative retinopathy. Blockages are more widespread, causing parts of the retina to be cut off from blood flow. As blood flow is lost, these parts of the retina can become damaged.
Stage 4: Proliferative diabetic retinopathy (PDR)
Proliferative diabetic retinopathy (PDR), or advanced retinopathy, occurs when new, abnormal blood vessels begin to grow inside the eye. When the retina loses nourishment, it signals the body to grow new blood vessels. These abnormal vessels may also grow into the center of the eye.
These changes can cause vision loss in several ways:
- The new, abnormal blood vessels leak easily. As leaky blood vessels outpace healthy ones, the retina gets even less nourishment.
- Leakage of blood into your eye can make it harder to see clearly, and in some cases can block your vision entirely.
- Scar tissue can form on the retina.
Minor bleeding can cause symptoms like dark spots and lines in your vision. Major bleeding can cause severe vision loss. This can include blindness, or the total loss of vision.
It’s important to seek treatment if you have diabetes and notice changes in your vision, like seeing cobwebs or floaters. Even if the problem seems to go away on its own, treatment is critical to prevent more serious vision loss from happening in the future.
It’s uncommon to have symptoms during the early stages of this condition. The symptoms of diabetic retinopathy often don’t appear until major damage occurs inside of the eye. You can prevent unseen damage by managing your blood sugar levels and getting regular eye exams to monitor your eye health.
When the symptoms do appear, they can include:
- seeing floaters or dark spots
- difficulty seeing at night
- blurred vision
- difficulty distinguishing colors
- loss of vision
Diabetic retinopathy usually affects both of your eyes.
High levels of blood sugar over long periods cause diabetic retinopathy. This excess sugar damages the blood vessels that supply the retina with blood. High blood pressure is also a risk factor for retinopathy.
The retina is a layer of tissue in the back of the eye. It’s sensitive to light, and when light enters your eye, it sends nerve signals to the brain. In the brain, those signals are translated into what you see.
When blood vessels of the retina are damaged, they can become blocked, which cuts off some of the retina’s blood supply. This loss of blood flow can cause other, weaker blood vessels to grow. These new blood vessels can leak and create scar tissue that can cause a loss of vision.
It’s hard to say exactly how many people with diabetes will develop retinopathy. In a 2016 study,
The longer you have diabetes, the higher your chances of developing diabetic retinopathy become. Keeping your diabetes under control can help slow the progression.
People with preexisting diabetes who are pregnant or are planning to become pregnant should have a comprehensive eye exam to determine if they have signs of retinopathy. This is because retinopathy can worsen rapidly during pregnancy.
Your doctor can diagnose diabetic retinopathy using a dilated eye exam. This involves the use of eye drops that make the pupils open wide, allowing your doctor to get a good look at the inside of your eye.
Your doctor will check for:
- abnormal blood vessels
- optic nerve damage
For a detailed look at your eye, your doctor can use one of the following tests:
- Fluorescein angiography. During this test, your doctor will inject a dye into your arm, allowing them to track how the blood flows in your eye. While your pupils are dilated, they’ll take pictures of the dye circulating inside of your eye to determine which vessels are blocked, leaking, or broken.
- Optical coherence tomography (OCT). An OCT exam is an imaging test that uses light waves to produce images of the retina. These images allow your doctor to determine your retina’s thickness. OCT exams help determine how much fluid, if any, has accumulated in the retina.
People with type 1 or type 2 diabetes should see an eye doctor on a regular basis, once every
Treatment for early diabetic retinopathy is focused on monitoring your eye health and managing your diabetes. Your doctor will likely recommend regular eye exams so that changes to your retina can be caught early. Your primary care physician or an endocrinologist can also help to slow these changes by helping you manage your blood sugar and general health with diabetes.
In advanced diabetic retinopathy, the treatment depends on the type of damage and severity of retinopathy.
Treatment options include injections, laser treatments, and surgery.
Injectable medications called anti-VEGF drugs work by blocking a protein that causes the growth of new, leaky blood vessels. These medications may also reduce swelling in the eye. These effects can improve your vision.
Anti-VEGF medications include:
- afilibercept (Eylea)
- bevacizumab (Avastin)
- ranibizumab (Lucentis)
These medications must be injected by a doctor, who will first numb your eye to reduce any discomfort. This treatment usually requires injections
Laser treatment, also known as photocoagulation, can help prevent vision loss. This type of surgery uses a laser to shrink or seal the blood vessels.
Your doctor will first use a local anesthetic so you’ll be comfortable during the procedure. They’ll also use medication to dilate your pupil. Then, your doctor will use laser equipment to shine a light into your eye.
There are two types of laser treatment used to treat diabetic retinopathy:
- Scatter laser treatment is used to help shrink blood vessels.
- Focal laser treatment is used to control or stop blood and fluid leakage.
It can sometimes take more than one session for laser treatment to be effective.
A surgical procedure, vitrectomy, involves removing the gel inside your eye, called vitreous fluid. This allows your doctor to clear away cloudy fluid that’s affecting your vision. They can also access your retina to make repairs to blood vessels or remove scar tissue.
Talk with your doctor about options to make you comfortable during the surgery. Your doctor can use medication to numb your eye or general anesthesia so that you’ll be unconscious during the procedure.
If you have diabetes, you can prevent diabetic retinopathy by taking steps to keep your blood vessels healthy:
- Keep your blood sugar within target levels as much as you can.
- Keep your blood pressure and cholesterol levels in a healthy range.
Other ways to prevent or manage the condition include the following:
- Get annual eye exams.
- Try to quit smoking, if you smoke.
- Get regular, moderate exercise several times per week. If you have retinopathy, check with your doctor to determine the best exercises for you.
Diabetic retinopathy can cause several other serious eye problems. These include diabetic macular edema (DME), neovascular glaucoma, and retinal detachment.
Diabetic macular edema (DME)
Diabetic macular edema (DME) happens when the center of the retina, or macula, begins to swell. Because the macula is important to precise vision, diabetic macular edema tends to make your vision blurry. It’s a fairly common complication among people with diabetes, affecting about
In advanced diabetic retinopathy, the growth of abnormal blood vessels can sometimes block fluid from draining out of the eye. When fluid can’t drain, this causes neovascular glaucoma. Symptoms include pressure and pain in your eye.
Retinopathy can cause scar tissue to form on your retina. Sometimes the scar tissue can pull the retina away from the back of your eye. Retinal detachment is a medical emergency that can cause permanent vision loss.
Warning signs of retinal detachment include:
- blurry vision
- sudden and numerous floaters
- darkened or dimmed vision
- flashing lights in the side of your vision
If you suspect retinal detachment, it’s important to seek medical care immediately by calling emergency services or having someone help you to the nearest emergency department.
Diabetic retinopathy is a serious eye condition that can lead to diminished eyesight or even blindness in those with diabetes. Fortunately, there are ways to prevent it and slow its progression.
If your doctor has diagnosed you with diabetes, it’s important to do the following:
- Get regular eye exams and physical checkups.
- Keep your blood sugar, cholesterol, and blood pressure at healthy levels.
- Be mindful of any changes you may notice in your vision, and don’t wait to discuss them with your doctor.
Because it’s possible to have diabetic retinopathy and not know it, it’s important for people with diabetes to keep up with regular eye exams.
If you have diabetes and notice changes in your eyesight, it could be a sign of diabetic neuropathy. Reasons to call your doctor include:
- diminished vision in one or both eyes
- seeing flashing lights
- seeing floaters
- eye pain or pressure
- blurred vision that you’ve noticed over time
Some eye symptoms can be a sign of an acute medical emergency, including:
- sudden vision loss in one or both eyes
- sudden blurred vision
- sudden eye pain
If you experience a rapid, unexplained change in your vision, contact your local emergency services or have someone help you to the nearest emergency room.