The short answerMost people with diabetes need a dilated retina exam at least once a year. With type 2 diabetes the first check should be at diagnosis, and with type 1 it usually starts within the first five years after diagnosis. This matters because diabetic retinopathy and macular oedema can develop while your vision is completely normal, and treatment works best before sight drops. Your doctor may change the interval depending on what the retina shows.
What does diabetes do to the retina?
Years of high blood sugar weaken the tiny blood vessels in the retina. They can leak fluid or blood, or close off, which leads to fragile new vessels growing. This is diabetic retinopathy. If fluid collects in the centre of the retina (the macula), it swells, a condition called diabetic macular oedema, which is one of the main causes of reduced vision in people with diabetes.
Why get checked if you see well?
Early diabetic retinopathy has no symptoms. You can read 6/6 and still have bleeds or leaks in the retina that only an exam will show. By the time you notice a change yourself, the disease may already be advanced. Regular checks are the only way to catch it in time.
Usual exam schedule
| Situation | First exam | Follow-up |
|---|---|---|
| Type 2 diabetes | At diagnosis | Usually yearly, or as your doctor advises |
| Type 1 diabetes (adults and children) | Usually within 5 years of diagnosis | Usually yearly, or as your doctor advises |
| Diabetes before pregnancy | Before pregnancy or early in it | Closer checks during and after pregnancy |
| Retinopathy already found | Depends on the stage | Sometimes every few months |
Pregnancy can speed up retinopathy in women who had diabetes before becoming pregnant, so they need a check before pregnancy or early on and closer follow-up. Gestational diabetes, which starts during pregnancy, does not usually need the same eye monitoring, but ask your doctor.
What lowers the risk?
- Keeping blood sugar within the target your diabetes doctor sets.
- Controlling blood pressure.
- Controlling cholesterol and blood fats.
- Stopping smoking.
- Keeping to your retina check schedule, even with no symptoms.
Can it be treated?
Yes. Depending on the findings, a doctor may use injections into the eye to reduce leakage and abnormal vessel growth, laser treatment, or surgery in advanced cases. These treatments protect vision best when they start early, before there is a large drop in sight.
Symptoms that need prompt review
- Blurred or reduced vision that does not improve.
- Vision that goes in and out of focus.
- New dark spots or strings floating in your vision.
- Dark or empty areas in your vision, or straight lines looking wavy.
- Sudden loss of vision: this needs to be seen the same day.
Frequently asked questions
How often should a diabetic have an eye exam?
Most people with diabetes need a dilated retina exam at least once a year. If retinopathy is found, checks may be more frequent. If several exams in a row are normal, your doctor may space them out.
My vision is fine. Why do I need a retina check?
Because diabetic retinopathy starts without symptoms while vision is normal. An exam finds it at a stage when treatment is more effective at protecting your sight.
Is an optician's sight test enough if I have diabetes?
No. A sight test measures how well you read the chart, not the health of the retina. You need a dilated retina exam by an eye doctor, or retinal photographs read by a specialist.
Does good sugar control prevent diabetic eye disease?
Controlling blood sugar, blood pressure and cholesterol lowers the risk of retinopathy and slows it down, but it does not replace regular eye checks.