Diabetic Retinopathy (DR), also known as diabetic eye disease, is an eye disease that affects the retina’s blood vessels. Anyone diagnosed with Type 1 or Type 2 diabetes and who struggles to sustain healthy blood sugar levels is at risk of developing Diabetic Retinopathy. The word “retinopathy” refers to any type of damage to the eye’s retina, which is the light-sensitive tissue lining the back of the eye.
In the early stages, DR is largely asymptomatic. However, it is a progressive disease, meaning that people with DR will eventually begin to experience mild symptoms like blurry vision, trouble reading, and difficulty seeing distant objects. Without treatment, Diabetic Retinopathy can result in a total loss of vision.
This article will discuss the stages, risk factors, treatment options, and prevention of Diabetic Retinopathy.
Diabetic Retinopathy is an eye condition that affects some people with diabetes. According to the American Academy of Ophthalmology, Diabetic Retinopathy develops when high blood sugar levels cause the blood vessels of the retina to swell and become damaged. In some cases, blood flow can be entirely obstructed.
The ICD-10 code for unspecified Diabetic Retinopathy is E10.31.
Diabetes Damages the Blood Vessels
Diabetic Retinopathy primarily affects the blood vessels and tissues in the back of the eye (retina). Ultimately, this can result in vision loss.
The retina contains many blood vessels, which supply necessary oxygen and nutrients to the photoreceptor cells and retinal tissue. Damage to these blood vessels can prevent the photoreceptors and retina from working properly, which results in cloudy or blurred vision. If DR is left untreated, the condition of the retina worsens and can lead to significant vision loss or blindness.
Damage to Macular Tissue
Diabetic Retinopathy also causes damage to the macular tissue. The macula sits at the center of the retina and assists with discerning details and color to create vision. Damaged blood vessels leak blood, which can cause the macula to swell and thus result in blurred central vision. It is important to seek prompt medical attention to avoid a total loss of central vision. Loss of central vision can make reading, recognizing faces and tasks of daily living difficult.
Prevalence of Diabetic Retinopathy
According to the Centers for Disease Control and Prevention (CDC), Diabetic Retinopathy affects nearly one-third of all adults over 40 who have diabetes. Other statistics on the prevalence of this condition include:
- 4.2 million adults in the U.S. live with Diabetic Retinopathy
- 655,000 adults in the U.S. have a vision-threatening form of DR
- From 2010 to 2050, the number of Americans with diabetic eye disease is expected to double, from 7.7 million to 14.6 million
- Diabetic Retinopathy and age related eye disease are the most common cause of vision impairment and blindness among working-age adults in the U.S.
Signs and Symptoms
For the most part, people with diabetic eye disease will experience little or no symptoms in the early stages of the condition. However, in the mid-to-advanced stages of the disease, more complex symptoms will present.
- Spots or “floaters” in the field of vision
- Blurry or poor night vision
- Blank and dark areas in the field of vision
- Total vision loss, or blindness.
If you are diabetic, and your vision suddenly becomes blurry or hazy, you should consider booking a consultation with an ophthalmologist.
An ophthalmologist will conduct a dilated eye exam to inspect the retina for any bulging blood vessels. In addition, they might conduct Optical Coherence Tomography and Fluorescein Angiography tests to help them identify damaged eye vessels.
- Optical Coherence Tomography (OCT): This procedure provides a cross-section image of your eye to see the thickness of your retina and where fluid could leak from damaged blood vessels.
- Fluorescein Angiography: First, your physician will take pictures of the inside of your dilated eyes. Next, they will inject a special dye into your arm to discover blocked or leaking blood vessels.
There are three stages of dry Age-Related Macular Degeneration. The first stage is associated with very few symptoms, the middle stage includes some or all symptoms, and the last stage denotes a total loss of central vision. Eye doctors do not classify wet AMD within stages, as wet AMD is always considered to be an advanced form.
Mild Non-Proliferative Diabetic Retinopathy
Stage 1 of DR is largely asymptomatic. People with this stage might develop microaneurysms (small red dots of dilated capillaries). While microaneurysms do not affect vision, these blood vessels can leak blood into the retina and cause the macula to become swollen, a condition called macular edema.
Moderate Non-Proliferative Diabetic Retinopathy
In Stage 2 of DR, microaneurysms begin to bulge and obstruct the flow of blood to the retina. Simultaneously, blood and fluid start to build up in the macula causing visible changes to the retina.
Severe Non-Proliferative Retinopathy
At Stage 3 of DR a large portion of blood vessels in the retina become weakened or damaged. Overall, this decreases blood flow to the retina and may cause the retina to grow new blood vessels.
Stage 4 is the most advanced stage of diabetic eye disease, where new blood vessels continue to grow in the retina and fluid leakage increases. In the final stage of DR, symptoms include blurry vision and in advanced cases, blindness.
Stage 4: Proliferative Diabetic Retinopathy (PDR): The Growth of New Blood Vessels
Proliferative Diabetic Retinopathy (PDR) is the final and most advanced stage of Diabetic Retinopathy.
As DR progresses, poor circulation from damaged blood vessels will deprive the retina of the oxygen it needs to function. The absence of oxygen triggers the growth of new, abnormal blood vessels in the retina. The abnormal blood vessels may begin to grow into the back of the eye, and potentially leak blood that clouds vision. If the bleeding is minimal, dark “floaters” may appear in the field of vision. If the bleeding is more severe, vision can be blocked entirely.
The abnormal growth of blood vessels in PDR may also form scar tissue, which can complicate the macula’s functioning and result in a detached retina. The latter is considered a medical emergency.
Advanced cases of PDR may also experience blood vessel growth in the drainage angle in the eye. This new vessel growth can block drainage pathways and increase pressure inside the eye, which may ultimately damage the optic nerve.
Diabetes is a condition associated with high blood sugar levels (hyperglycemia). Excessive amounts of sugar in the bloodstream can damage blood vessels within the retina, leading to swelling and leakage. Hyperglycemia also permits sugar to accumulate in the eye’s lens, which can change the curvature of the lens and thus affect vision.
Over time, damaged blood vessels can completely prevent blood from reaching the retinal tissue. In such cases, new blood vessels may form on the surface of the retina to supply the retina with the oxygen-rich blood it needs to function. As the condition worsens, however, the new blood vessels may also leak into the back of the eye, which leads to vision loss.
There are several steps you can take to manage DR. Most importantly, experts advise that anyone with diabetes should receive an annual eye exam. During these examinations, the ophthalmologist may discover symptoms of Diabetic Retinopathy, and begin timely treatment, which ultimately can reduce the progression of the disease.
Other prevention tips include:
- Eat a balanced, healthy diet and engage in regular physical activity to help control your blood pressure, blood sugar, and cholesterol.
- Avoid smoking
- Contact an eye specialist immediately if you notice any vision changes
- Follow healthcare provider’s recommendations for managing diabetes
Several treatment options exist for diabetic eye disease depending on the stage of the condition. Typically, mild cases require careful diabetes management, which may include a medication designed to control your blood sugar levels.
People with more advanced Diabetic Retinopathy might require laser treatment, injections, or surgery to improve their condition. Laser surgery is used to seal leaky blood vessels and prevent further leakages. Injection of medications into the eye is used to decrease inflammation and stop the formation of abnormal blood vessels. Surgical procedures are employed to remove and replace the vitreous fluid in the eye, and also to repair retinal detachment.