Causes and Risk Factors
Years of elevated glucose weaken retinal capillaries, causing them to leak, close off, or sprout fragile new vessels. Retinopathy risk climbs with:- Duration of diabetes: The longer you have lived with type 1 or type 2 diabetes, the higher the likelihood of retinal changes.
- Blood sugar control: Higher average glucose (A1C) accelerates vessel damage; tight control slows it dramatically.
- High blood pressure and cholesterol: Both add stress to already-fragile vessels and worsen leakage.
- Kidney disease, pregnancy, and smoking: Each can accelerate retinal damage and calls for closer eye monitoring.
- Very rapid changes in control: When long-standing high glucose is brought down quickly, retinopathy can briefly worsen before it improves, so the eyes are watched more closely during a major change in therapy.
Symptoms
Early retinopathy is silent. As it advances, people may notice:- Floaters: New spots, strings, or cobwebs drifting across vision, sometimes from small bleeds.
- Blurred or fluctuating vision: Swelling of the central retina (macular edema) blurs reading and detail vision; glucose swings also shift focus day to day.
- Dark or empty patches: Areas of missing vision where retinal tissue has been damaged.
- Sudden vision loss: Bleeding into the eye or retinal detachment can dim vision abruptly — an emergency.
- Poorer night and contrast vision: Colors may look washed out and fine print harder to read, particularly in dim light.
Diagnosis
An annual dilated eye exam allows a specialist to see the retina directly and grade the disease, from mild nonproliferative changes to proliferative retinopathy with new vessel growth. Imaging such as optical coherence tomography (OCT) measures macular swelling, and dye-based imaging of the retinal circulation shows where vessels are leaking or have closed off. Retinal photographs taken in a primary-care office can screen for disease and flag who needs a specialist, but they do not replace a full dilated examination once retinopathy is present. People with diabetes are also more prone to cataracts and glaucoma, so the same yearly visit screens for all three.Treatment
Treatment protects remaining vision and works best when started early:- Control the fundamentals: Meeting A1C, blood pressure, and cholesterol targets is the single most powerful way to prevent and slow retinopathy.
- Anti-VEGF eye injections: Medicines injected into the eye reduce macular swelling and shrink abnormal vessels, preserving and often improving vision.
- Laser therapy: Focused laser treatment seals leaking vessels and quiets areas of oxygen-starved retina in proliferative disease.
- Vitrectomy surgery: For severe bleeding or retinal detachment, surgical removal of blood and scar tissue can restore useful vision.
- Keeping the follow-up schedule: Your eye specialist sets the interval — every few months while disease is active, yearly once the retina is stable — and keeping those appointments protects vision as much as any single treatment.