Diabetic Retinopathy

What is Diabetic Retinopathy?

Diabetic retinopathyis a leading cause of preventable blindness in the US today. It is a serious progressive eye disease caused by too much glucose in the blood (high blood sugar). Over time, high blood sugar damages the blood vessels in the retina, the light-sensitive layer of tissue in the back of your eye and damages the macula (center of the retina, responsible for color vision, fine detail, and central vision). This can cause bleeding into the vitreous (the viscose fluid that fills the eye) resulting in gradual vision loss that can lead to permanent blindness.

Diabetes is the primary risk factor for diabetic retinopathy. High blood pressure (hypertension), kidney disease, and high cholesterol are also risk factors.

Advanced diabetic retinopathy can lead to diabetic macular edema (DME), neovascular glaucoma, and retinal detachment. According to the National Institutes of Health (NIH) National Eye Institute (NEI), more than 50% of people with diabetes of any type are at risk developing diabetic retinopathy. The longer one has diabetes, the greater their chance of developing this disease.

What are the Symptoms of Diabetic Retinopathy?

Early-stage diabetic retinopathy may present no symptoms or mild symptoms. Without treatment symptoms often worsen over time:

• Blurred vision
• Floaters
• Eye pain or redness
• Difficulty seeing in the dark
• Difficulty seeing up close or at a distance

Untreated or poorly treated diabetes, can exacerbate the progression of eye disease and untreated diabetic retinopathy may lead to irreversible blindness:

What are the First Signs of Diabetic Retinopathy?

Even before subtle early-stage changes in vision are noticeable, an ophthalmologist can spot the following diabetic retinopathy indicators during a comprehensive dilated eye exam:

• Bleeding in the retina and/or vitreous (hemorrhage)
• Bulging and/or ruptured blood vessels (microaneurysm)
• Excess fluid in the macula (macular edema)
• Fatty waste materials  (lipid deposits)
• Abnormal blood vessels
• New growth of abnormal nerves and blood vessels (neovascularization)

Since a significant percentage of people with diabetes will develop diabetic retinopathy, it’s crucial to schedule a comprehensive dilated eye examination as soon as you are diagnosed. Be proactive and be vigilant. Repeat dilated eye exams as frequently as your ophthalmologist recommends. Early detection is key to successful treatment and more positive outcomes.

What Eye Changes Occur with Diabetic Retinopathy and What Does it Look Like?

Diabetic retinopathy can present in multiple ways, each uniquely affecting vision. See a side-by-side comparison of a healthy eye and an eye with diabetic retinopathy.Changes in vision likewise depend on how advanced the disease is. These include floaters, blurred vision, black spots, “cobwebs,” and streaks. The NIH offers this video to help understand what someone with diabetic retinopathy might see.

How to Test for Diabetic Retinopathy

Your eye doctor can check for diabetic retinopathy during a comprehensive dilated eye exam. Eye drops may be administered to dilate your pupils, allowing for a closer look for any abnormalities inside and in the back of the eyes. When a doctor detects changes of concern, they may recommend additional diagnostic tests, including:

• Fluorescein Angiography: Once the eyes are dilated, dye is injected into a vein in the arm and pictures are taken as the dye circulates through the blood vessels in the eye, revealing breaks, leaks, and/or blockage.
• Optical coherence tomography (OCT): The eyes may or may not be dilated for this imaging test that captures images of the retina, revealing thickness of tissue and any fluid leakage. OCT exams are also used to monitor treatment.

What are the Stages of Diabetic Retinopathy?

There are two types of diabetic retinopathy: nonproliferative (early) and proliferative (advanced). The disease progresses through four stages:

• Stage 1: Mild nonproliferative diabetic retinopathy (NPDR) features swollen blood vessels.
• Stage 2: Moderate nonproliferative diabetic retinopathy is marked by increased blood vessel (vascular) swelling that blocks blood flow to the retina and causes blurred vision.
• Stage 3: Severe nonproliferative diabetic retinopathy presents severe vascular swelling and decreased blood flow. The growth of fragile new blood vessels causes the retina to swell and damages the macula. Sudden complete permanent vision loss may occur.
• Stage 4: Proliferative diabetic retinopathy (PDR) is identified by the increased new growth of weak, poorly functioning blood vessels that leak and cause scarring. Scar tissue can pull the retina from the back of the eye, blurring vision, causing reduced field of vision, and, in some cases, irreversible blindness.

What is the Treatment for Diabetic Retinopathy?

Treatment begins with prevention. You can significantly reduce your risk by working with your doctor to maintain healthy blood sugar levels. Anyone diagnosed with diabetes should have regular comprehensive dilated eye exams to diagnose the disease in its earliest stage. Once diagnosed with diabetic retinopathy, your ophthalmologist will recommend treatment based on how far the disease has progressed. Treatment may include injections, laser, surgery, and other interventions.

Can Diabetic Retinopathy be Reversed?

Diabetic retinopathy cannot be reversed, but progression can be slowed through medication, and other treatments. Maintaining healthy blood glucose, cholesterol levels, and blood pressure before the disease has a chance to develop or progress is essential.

Managing diabetes – the cause of diabetic retinopathy – is the best way to reduce your risk. The Centers for Disease Control (CDC) reports that 90% of blindness in US adults caused by diabetes is preventable. Work with your healthcare team to maintain a healthy blood glucose level. Learn more about diabetic retinopathy from the American Academy of Ophthalmology, National Eye Institute, and the American Diabetes Association.