Diabetic retinopathy is a chronic eye disease that arises as a complication of diabetes, affecting the retina — the specialized tissue at the back of the eye that captures light and enables clear sight.

This condition develops when prolonged elevations in blood sugar gradually damage tiny blood vessels supplying the retina, leading to leakage, blockage, poor circulation, and eventually new fragile vessels that worsen structural stress.

The Underlying Causes: How Diabetes Damages the Retina

Capillary Leakage: Tiny vessels begin to leak fluid into retinal layers, resulting in swelling and blurred vision.

Blood Vessel Blockage: Blocked vessels slow or prevent oxygen and nutrient flow to retinal cells.

Abnormal Vessel Growth: In advanced stages, the retina responds to poor circulation by growing new vessels. These vessels are fragile and prone to bleeding, contributing further to visual disruption.

Stages of Diabetic Retinopathy

This disease progresses through stages, each reflecting escalating severity:

1. Non-proliferative Diabetic Retinopathy (NPDR)

This early form is marked by damaged retinal blood vessels that leak fluid and small amounts of blood. These changes can appear gradually, and many affected individuals have no vision symptoms in early NPDR.

2. Proliferative Diabetic Retinopathy (PDR)

As the disease advances, the retina attempts to compensate for poor circulation by forming new vessels. Unfortunately, these new vessels are weak and vulnerable to bleeding into retinal tissue or other inner eye structures. PDR significantly increases the risk of vision loss and requires more urgent intervention.

Signs and Symptoms: What Changes to Expect

The early phases of diabetic retinopathy often do not produce symptoms. When changes begin to affect sharp visual performance, the following may occur:

- Blurred or fluctuating clarity of vision

- Difficulty reading fine detail

- Dark or floating spots

- Distorted images or altered color perception

- Shadows or blind spots in the field of view

Screening and Diagnosis: The Path to Early Detection

A comprehensive eye examination is the most effective way to diagnose diabetic retinopathy before permanent vision loss occurs. This typically includes:

Dilated Eye Exams: Special drops widen the pupils, allowing close visual inspection of retinal tissues and blood vessels.

Retinal Photography and Imaging: Advanced imaging like optical coherence tomography (OCT) reveals subtle fluid accumulation and structural changes.

Fluorescein Angiography: This specialized test tracks blood flow through retinal vessels using a harmless contrast dye.

A respected authority in diabetic eye disease, Lisa Olmos de Koo, M.D., Professor of Ophthalmology at the University of Washington School of Medicine, highlights the importance of early assessment: “If you get a new diagnosis of diabetes, especially type 2, it’s important to go to your eye doctor and get it checked.”

Treatment Approaches: Tailored to Disease Stage

Treatment strategies for diabetic retinopathy are aimed at slowing progression, stabilizing vascular health, and preserving vision:

Laser Photocoagulation: Focused laser energy seals leaking vessels and reduces growth of abnormal blood vessels.

Injections of Anti-VEGF Agents: Medicines delivered directly to inner eye tissues help reduce swelling and suppress abnormal vessel growth.

Steroid Treatments: Steroid therapy may be used to reduce retinal swelling when appropriate.

Surgical Intervention: In advanced PDR with significant bleeding or retinal changes, surgical procedures may be necessary.

Living With Diabetic Retinopathy: Prevention and Management

Prevention begins with effective management of underlying diabetes and consistent communication with healthcare teams. Key actions include:

- Maintaining healthy blood sugar levels according to medical guidance

- Regular eye screenings as part of long-term care

- Addressing co-existing health factors such as blood pressure and cholesterol

Diabetic retinopathy is a progressive vascular condition that develops from the effects of diabetes on the eye’s microcirculation. It can progress from subtle, asymptomatic changes to serious vision-threatening stages if left unrecognized. Collaborative care that includes diabetes control, routine eye checks, and timely therapy serves as the foundation for protecting long-term visual health.