Eye Screening and Retinopathy

Diabetes can damage the small blood vessels at the back of the eye. In Type 1 the screening timetable looks different from Type 2, and there is a reason.

Retinopathy is estimated to take at least five years to develop after blood sugar first starts running high. In Type 2, the condition is usually present for years before it is found, so damage can already exist at diagnosis and screening starts immediately. In Type 1, the diagnosis is usually caught within weeks of onset, so the clock genuinely starts then — which is why the first dilated examination is recommended within five years of diagnosis.

After that, if no retinopathy is found on one or more annual exams and your glucose is in range, screening every one to two years may be reasonable. If any retinopathy is present, it becomes at least annual.

Dilated is the key word. Drops widen the pupil so the whole retina can be seen. A vision test for spectacles does not do this and will not detect early damage.

Early retinopathy has no symptoms. By the time you notice blurring, floaters or dark patches, it is usually well established — those symptoms mean be seen soon, not wait for the next appointment.

Indian data recorded retinopathy in 13.4% of a childhood diabetes cohort, which is a reminder that this is not a distant, elderly problem.