The National Eye Institute cautions people with diabetes that diabetic retinopathy is the most common eye disease they need to be watchful of, stating it’s “a leading cause of blindness in American adults.” To help diabetics understand what diabetic retinopathy is and how to manage it, medical animator Mark Erickson of JirehDesign.com has created a brief, animated video explaining the essentials.* 

Eye diseases caused by diabetes (0:05)

Over 420 million people around the globe are living with diabetes. If left unchecked, diabetes can damage many bodily functions, including eyesight. 

Several eye diseases can occur from diabetes, most commonly:

• Glaucoma,
• Cataracts, and
• Diabetic retinopathy.

What is diabetic retinopathy? (0:30)

In diabetic retinopathy, small blood vessels in the retina are damaged by elevated blood sugar. The retina is a thin layer of light-absorbing tissue lining the back of the eye on the inside of the eye wall, and it is critical for sight. The retina is analogous to film in a camera, and the retina is what does the “seeing” in one’s eye. Diabetic retinopathy typically affects both eyes, but it may be asymmetrical.

Two stages of diabetic retinopathy (0:41)

Diabetic retinopathy can be divided into two stages:

• Non-proliferative diabetic retinopathy (NPDR), and
• Proliferative diabetic retinopathy (PDR)

NPDR (0:53) is the earliest stage of the disease in which microaneurysms, or tiny areas of balloon-like swelling, form in the blood vessels supplying the retina. As more of them develop and begin to cluster, fluid can leak into the retinal layers. 

As the disease advances, retinal blood vessels can change shape and leak, leaving whitish-yellow fat-like deposits. With blood vessels damaged, blood transport can become compromised and the retina deprived of nutrients and oxygen. 

The macula, at the center of the retina, sometimes swells and blurs vision in a condition called diabetic macular edema (DME). 

• DME is the most common reason for vision loss in diabetic retinopathy and may require eye drops, laser therapy, or painless medication injections into the eye.

PDR (2:02) is the advanced stage of the disease. As more retinal blood vessels become damaged, the retina signals for more blood and oxygen, and new vessels are formed in a process called neovascularization. 

These new vessels are weak, however, and will often bleed into the vitreous chamber—the main body of the eyeball. A person with blood in the vitreous may hardly notice anything is wrong or may have total loss of vision. 

Symptoms of blood in the vitreous include:

• Seeing small, floating dark spots,
• A reddish tint to vision, 
• Seeing randomly shaped darkened sections, and/or
• Hazy loss of vision. 

Common PDR treatments include:

• Laser therapy, and
• Intravitreal medication injections.

If uncontrolled, severe PDR can lead to scar tissue from bleeding and neovascularization (the development of new blood vessels). The scar tissue and new blood vessels can contract, causing the retina to detach from its normal position. This can lead to permanent loss of vision. Surgery is needed for this kind of retinal detachment.

Managing diabetic retinopathy (3:20)

You can’t always control diabetic retinopathy, but managing blood sugar and blood pressure, getting regular eye exams, and treating any visual issues early on will significantly lower your risk of severe vision loss.

For more on diabetic retinopathy

A one-minute video by the National Eye Institute further details how diabetic eye disease can result in vision loss.

*Erickson, M. (2019, August 15). Diabetic Retinopathy [Video file]. Retrieved from https://www.youtube.com/watch?v=Tv7-2r8Ki1U.