Diabetic retinopathy

What it is

High blood sugar over time weakens and blocks tiny retinal blood vessels. Early non-proliferative retinopathy causes microaneurysms and small haemorrhages. As disease advances, vessels may close, starving areas of retina, or trigger new fragile vessels (proliferative retinopathy) that can bleed or scar the retina.

Symptoms

Many people have no symptoms until disease is moderate or advanced. Later signs include:

• Blurred or fluctuating vision
• Floaters from bleeding inside the eye
• Dark or empty patches in sight
• Poor night vision
• Sudden vision loss if a large bleed occurs

Diabetic macular oedema (DME)

When leaky vessels cause fluid in the macula, central vision blurs or distorts. DME can occur at any stage of retinopathy and is treated with anti-VEGF injections, laser or surgery — not only with general diabetes control. Read the dedicated diabetic macular oedema page for detail; screening OCT scans detect swelling before you notice symptoms.

Screening and stages

National programmes photograph the retina at regular intervals based on diabetes type and existing changes. Mild disease may need annual review; proliferative or treated disease needs hospital eye clinics. Never skip screening because vision feels normal.

Treatment

Tight diabetes and blood pressure management slow progression. Laser photocoagulation treats ischaemic retina or macular leakage in selected cases. Anti-VEGF injections treat DME and some proliferative complications. Vitrectomy clears severe vitreous haemorrhage or traction. Plans are coordinated between diabetes and ophthalmology teams.

Prevention

Attend every screening visit, maintain HbA1c and blood pressure targets agreed with your diabetes team, stop smoking, and report new floaters, blur or distortion promptly.