Diabetic Eye Problems

Diabetes damages the blood vessels of the retina, lens, and optic nerve — and diabetic retinopathy is now the leading cause of preventable blindness in working-age Indian adults. The key message is simple: every person with diabetes needs a dilated retinal exam every year, whether their vision feels fine or not.

The main diabetic eye problems

• Diabetic retinopathy — bleeding and leaking from retinal vessels.
• Diabetic macular oedema — fluid at the centre of vision; the commonest cause of vision loss in diabetes.
• Cataract — develops earlier and faster in diabetes.
• Glaucoma — a type called neovascular glaucoma is diabetes-related.
• Temporary blurring with sudden changes in blood sugar — the lens swells. Stabilises with good control.

Screening — the single most important thing

• Type 2 diabetes: dilated retinal exam at diagnosis, then yearly. Earlier if sugars are poorly controlled.
• Type 1 diabetes: start screening 5 years after diagnosis, then yearly.
• Pregnancy with pre-existing diabetes: screen in the first trimester and more often through pregnancy.
• Retinopathy usually causes no symptoms until late — don't rely on feeling fine.
• Mobile retinal-camera screening is available at many Indian primary centres and diabetic clinics; a tele-ophthalmology referral follows if abnormal.

What changes the outcome

• Good blood sugar control (HbA1c target individualised), blood pressure control, stopping smoking, cholesterol management.
• Laser treatment for advanced retinopathy.
• Anti-VEGF injection class for macular oedema and wet disease — highly effective if started early.
• Vitrectomy surgery for advanced cases with bleeding or detachment.
• Delay = permanent vision loss. The retina does not regenerate.

Emergency signs

• Sudden loss of vision, shower of new floaters, flashes, or a curtain across vision — possible retinal detachment or massive haemorrhage — go same day.
• Severe eye pain with red eye in someone with long-standing diabetes — rule out neovascular glaucoma.