What Is Diabetic Retinopathy?
Diabetic retinopathy is an eye condition that causes changes to the blood vessels in the part of your eye called the retina. That's the lining at the back of your eye that changes light into images. The blood vessels can swell, leak fluid, or bleed, which often leads to vision changes or blindness. It usually affects both eyes. When left untreated, diabetic retinopathy can scar and damage your retina.
Diabetic retinopathy is the most common cause of vision loss for people with diabetes. It’s the leading cause of blindness for all adults in the U.S.
Types of Diabetic Retinopathy
The early stage of diabetic retinopathy causes nonproliferative diabetic retinopathy. In this stage, tiny blood vessels in the retina leak fluid or blood, and your retina may also swell.
Your retina’s blood vessels can become blocked, preventing blood from reaching your macula, the part of your retina that helps you see what is in front of you. In some cases, your retina may also contain tiny particles called exudates.
These changes can affect your vision, making it blurry or causing mild vision loss. You might not realize that your vision is changing at first. Your doctor may notice these changes during an eye test.
Advanced diabetic retinopathy
Proliferative diabetic retinopathy is the advanced type of diabetic retinopathy. In this stage, new blood vessels start growing on your retina.
These new vessels are abnormal and often fragile. They may split and bleed into your vitreous, a watery gel-like substance in your eye. If there’s a small amount of bleeding, you might only notice some spots or floaters in your vision. However, if the bleeding is substantial, it could completely block your vision.
These new blood vessels can grow to form scar tissue, which can then cause more problems in your retina or cause it to detach or pull away from where it’s supposed to be.
In addition, any abnormal blood vessels in your eye can close up your iris (the colored part of your eye) and your cornea (the outer clear area of your eye). When this happens, it prevents fluid from leaving your eyes, causing pressure buildup. Pressure buildup can damage your optic nerve, the nerve that sends visual images from your eye to your brain so you can see.
All of these changes in your eye can cause symptoms like seeing flashing lights or sudden and severe vision loss without any pain.
Hypertensive Retinopathy vs. Diabetic Retinopathy
Hypertensive retinopathy may cause symptoms that could be mistaken for diabetic retinopathy. It happens when long-term high blood pressure damages the retina. When the pressure in your retina blood vessels is high, they can stay tightened for too long. This tightening can cause your blood vessels to become stiff and thick. These changes to your blood vessels can disrupt blood flow, causing you to eventually have problems like retina swelling and detachment and vision loss.
Most people with hypertensive retinopathy have no symptoms, but if they do, their primary symptom is being unable to see clearly.
On the other hand, diabetic retinopathy happens when high blood sugar levels damage the blood vessels in the retina, causing them to leak fluid and swell. They can become blocked, so blood can’t flow through them. Your retina may also grow abnormal vessels that cause more eye problems and damage.
When you have diabetic retinopathy, you may have no symptoms at first. But as the disease progresses, you’ll start having symptoms like blurry or double vision, eye floaters, eye pain or pressure, poor vision at night, and flashing lights.
Having high blood pressure can worsen your diabetic retinopathy symptoms.
Diabetic Retinopathy Symptoms
You might not have any signs of diabetic retinopathy until it becomes serious. When you do have symptoms, you might notice:
- Loss of central vision, which is used when you read or drive
- Not being able to see colors
- Blurry vision
- Holes or black spots in your vision
- Floaters, or small spots in your vision caused by bleeding
- Vision changes that go from blurry to clear and clear to blurry
- Blank or dark areas in your vision
- Being unable to see well at night
- Seeing flashing lights
- Difficulty reading
- Trouble seeing things that are far away
Diabetic Retinopathy Causes
If your blood glucose level (blood sugar) is too high for too long, it blocks off the small blood vessels that keep your retina healthy. Your eye will try to grow new blood vessels, but they won’t develop correctly. The blood vessels start to weaken. They can leak blood and fluid into your retina. This can cause another condition called macular edema. It can make your vision blurry.
As your condition gets worse, more blood vessels become blocked. Scar tissue builds up because of the new blood vessels your eye has grown. This extra pressure can cause your retina to tear or detach.
This can also lead to eye conditions like glaucoma or cataracts (the clouding of your eye’s lens) that may result in blindness.
Diabetic Retinopathy Risk Factors
If you have any form of diabetes -- type 1, type 2, or gestational -- you can get diabetic retinopathy. Your chance goes up the longer you have diabetes. Almost half of Americans diagnosed with diabetes have some stage of diabetic retinopathy. And only about half of them know they have this disease.
Other things that can raise your odds of diabetic retinopathy include:
- High blood pressure
- High cholesterol
- Tobacco use
- Being Black, Hispanic, or Native American
- Puberty
- Pregnancy
- Genetics
- Obesity
- Kidney disease
- Having a vitamin D deficiency
Diabetic Retinopathy Stages
Diabetic retinopathy tends to go through these four stages:
- Mild nonproliferative retinopathy. In the disease’s earliest stage, tiny blood vessels in your retina change. Small areas swell. These are called microaneurysms. Fluid can leak out of them and into your retina.
- Moderate nonproliferative retinopathy. As your disease gets worse, blood vessels that should keep your retina healthy swell and change shape. They can’t deliver blood to your retina. This can change the way your retina looks. These blood vessel changes can trigger diabetic macular edema (DME). That’s swelling in the area of your retina called the macula.
- Severe nonproliferative retinopathy. In the third stage, many blood vessels get blocked. They can’t deliver blood to your retina to keep it healthy. Areas of your retina where this happens make special proteins called growth factors that tell your retina to grow new blood vessels.
- Proliferative diabetic retinopathy (PDR). This is the most advanced stage. New blood vessels grow inside your retina and then into the jelly inside your eyeballs called vitreous humor. Fragile new blood vessels are more likely to leak fluid and bleed. Scar tissue starts to form. This can cause retinal detachment, when your retina pulls away from the tissue underneath. This can lead to permanent blindness.
Diabetic Retinopathy Diagnosis
Your eye doctor can usually tell if you have diabetic retinopathy during your eye exam.
Pupil dilation. Your doctor will dilate your pupils to look for changes in your eye’s blood vessels or see if any new ones have grown. They'll also see if your retina is swollen or detached.
Fluorescein angiogram. This test can tell your doctor if you have DME or severe diabetic retinopathy. It shows if any of your blood vessels are leaking or damaged. Your doctor will give you a shot with fluorescent dye into a vein in your arm. When the dye reaches your eyes, your doctor will be able to see images of the blood vessels in your retina and spot any serious problems.
Optical coherence tomography. This test produces images of your retina. These images show your doctor how thick your retina is, if any fluid has leaked into it, and how much has leaked. They can also use this test to see how well your treatment is working.
Diabetic Retinopathy Treatment
Treatments for diabetic retinopathy include:
Anti-VEGF injection therapy. Drugs that block vascular endothelial growth factor (VEGF), a protein that makes abnormal blood vessels grow in your eye, can reverse the blood vessel growths and lower fluid buildup in your retina. Anti-VEGF drugs include aflibercept (Eylea), bevacizumab (Avastin), and ranibizumab (Lucentis).
Focal/grid macular laser surgery. Lasers make tiny burns on the leaky areas of vessels in your macula. You may need anti-VEGF therapy after this surgery.
Corticosteroids. Doctors can implant or inject these medications into your eye. There are both short-term and long-acting types. Steroids can raise your chance of glaucoma or cataracts. Your eye doctor will monitor the pressure in your eye if you take them.
Scatter laser surgery. This treatment makes up to 2,000 tiny burns to treat spots where your retina has detached from the macula. This can shrink abnormal blood vessels. You may need two or more sessions. Laser surgery can save your central vision, but it may lessen your side, color, or nighttime vision. It works best if you get it before those new vessels start to bleed.
Vitrectomy. If blood vessels leak into your retina and vitreous humor and your vision clouds, you may need to have this procedure. It removes the leaked blood so you can see better. This can treat cloudy vision.
Your doctor will tell you if any of these treatments are right for you. They’ll do them in the doctor's office or in the hospital.
Diabetic Retinopathy Complications
Diabetic retinopathy causes changes in your eyes that, if left untreated, can cause other serious eye problems.
Diabetic macular edema. Diabetic macular edema (DME) is a serious complication of diabetic retinopathy. A healthy macula gives you sharp vision straight in front of you. This is what you need to drive, read, and see other people’s faces. If your diabetic retinopathy causes fluid buildup and swelling in your macula, you can get DME.
DME is the most common reason people with diabetic retinopathy lose their vision, and about half of people with diabetic retinopathy get DME. You’re more likely to get DME at later stages of diabetic retinopathy, but it can happen at any point.
Sometimes, vision loss from DME can’t be reversed.
Vitreous hemorrhage. When new blood vessels develop from diabetic retinopathy, they may break and bleed into your vitreous, causing you to have eye floaters or dark spots. How many floaters you have depends on how serious the bleeding is. The bleeding could be so much that you get many floaters blocking your vision. However, the bleeding could go away within weeks to a few months, and as long as your retina hasn’t been damaged, your vision may return.
Retinal detachment. Scar tissues can form as abnormal blood vessels grow on your retina. These scar tissues can pull your retina away from the back of your eyes. You might have symptoms like floaters, serious vision loss, or light flashes when this happens.
Glaucoma. New blood vessels in the iris can block fluid from flowing out of your eyes, leading to fluid buildup and adding pressure to your eyes. This buildup and pressure lead to glaucoma, a condition involving optic nerve damage. Glaucoma is the second most common cause of blindness.
Blindness. Diabetic retinopathy, as well as its complications like glaucoma and retinal detachment, can cause you to lose your vision completely, leading to blindness.
Prevention
Work with your doctor to keep your blood sugar and blood pressure at good levels. This will slow down diabetic retinopathy and maybe even stop it from happening.
Here are more tips to prevent diabetic retinopathy:
- Make sure you see an eye doctor at least once a year for a complete eye exam.
- If you have diabetes and are pregnant, have a thorough eye exam during your first trimester.
- Follow up with your eye doctor during pregnancy. Tell your eye doctor if you develop gestational diabetes.
- Don’t smoke if you have diabetic retinopathy or diabetes.
Takeaways
Diabetic retinopathy is an eye problem that happens when high blood sugar levels cause damage to existing blood vessels in your eyes and cause new abnormal ones to form. These changes may cause no or mild symptoms in the early stages, but later on, you’ll start having symptoms like eye floaters and vision problems. Go for routine eye tests, especially if you have diabetes, as your doctor might be the first to discover you have diabetic retinopathy. Also, see your doctor immediately if you notice any changes in how you see.
Diabetic Retinopathy FAQs
Can diabetic retinopathy be reversed?
Diabetic retinopathy can't be reversed, but treatment can prevent it from progressing and prevent your vision from worsening.
Can you live a normal life with diabetic retinopathy?
Yes, you can live a normal life with diabetic retinopathy as long as you take your prescribed medicines regularly and keep your blood sugar levels, as well as other underlying conditions like high blood pressure, under control.
What is the first sign of diabetic retinopathy?
You’ll have no signs at all in the beginning. But later on you might notice vision problems like difficulty reading from time to time.
What worsens diabetic retinopathy?
Having untreated or poorly managed diabetes, high blood pressure, high cholesterol, kidney disease, and obesity can worsen diabetic retinopathy.
