woman trying on glasses Diabetes can have a serious impact on your eyes, especially if blood sugar levels remain high over time. One of the most common and serious eye complications is diabetic retinopathy, a condition that damages the small blood vessels in the retina, the light-sensitive layer at the back of the eye.

If left untreated, diabetic retinopathy can lead to permanent vision loss. Fortunately, early detection and new treatments are helping people with diabetes protect their vision more effectively than ever.

What Causes Diabetic Retinopathy?

High blood sugar levels can damage the delicate network of blood vessels in the retina. This damage happens in several stages:

1. Leaky Blood Vessels

High glucose levels weaken the cells that line retinal blood vessels, especially the endothelial cells and pericytes that maintain vessel integrity. When these cells are damaged, the vessels can leak fluid and proteins into the retina. This leakage causes swelling and blurred vision, and marks the beginning of diabetic retinopathy.

2. Blocked Blood Flow

Chronic hyperglycemia can also block the tiny capillaries that feed the retina. In nonproliferative diabetic retinopathy (NPDR), these blockages reduce blood and oxygen supply, causing areas of retinal tissue to become starved and damaged. If this progresses to proliferative diabetic retinopathy (PDR), larger areas of the retina are affected, triggering the retina to respond in dangerous ways.

3. Abnormal Blood Vessel Growth

When the retina doesn’t get enough oxygen, it releases a protein called vascular endothelial growth factor (VEGF). VEGF encourages the growth of new blood vessels, but these vessels are abnormal, fragile, twisted, and prone to bleeding. This process, called neovascularization, can cause:

Vitreous hemorrhage (bleeding into the gel inside the eye)
Tractional retinal detachment (pulling the retina away from the back of the eye)

Both are medical emergencies and can result in severe vision loss.

New Insights and Innovations

Ongoing research and technological advances are reshaping how we understand, detect, and treat diabetic eye disease.

The Gut-Retina Connection

Recent studies suggest a gut-retina axis, where changes in gut bacteria may trigger immune responses that affect the retina. This connection could open new ways to treat or prevent retinopathy using diet or probiotics.

Artificial Intelligence in Eye Care

AI tools now help screen for diabetic retinopathy by analyzing retinal photos. These systems are already being used in clinics to quickly identify early signs of damage, especially in places with limited access to eye specialists.

Non-Invasive Imaging

Optical Coherence Tomography Angiography (OCTA) is a cutting-edge imaging technique that captures high-resolution images of the eye’s blood vessels without needing dye injections. It can detect very early changes in blood flow and vessel structure.

Anti-VEGF Therapies

One of the most effective treatments for advanced diabetic retinopathy is anti-VEGF injections (like ranibizumab or aflibercept). These medications block the growth of abnormal vessels and help reduce retinal swelling.

How to Protect Your Vision with Diabetes

The most effective way to prevent diabetes-related eye damage is to effectively manage your blood sugar, blood pressure, and cholesterol levels. Regular eye exams are also essential:

Type 1 Diabetes: Get your first eye exam within 5 years of diagnosis.
Type 2 Diabetes: Get your eyes checked at the time of diagnosis.
Pregnant with Diabetes? An eye exam is recommended in the first trimester.

Bottom Line:
Understanding diabetic retinopathy and why diabetes causes eye damage empowers you to take action. Thanks to new innovations and research, protecting your vision is more achievable than ever.

Explore More on Eye Complications

This article is part of a series covering different eye complications, their development, and what can be done to prevent or treat them. Click the links below to learn more: