Diabetic retinopathy is a common complication of diabetes. It occurs when high blood sugar levels damage the cells at the back of the eye (known as the retina). If it isn’t treated, it can cause blindness.
It’s important for people with diabetes to control their blood sugar levels. Everyone with diabetes who is 12 years old or over should have their eyes examined once a year for signs of damage (see below).
All people with diabetes are at risk of getting diabetic retinopathy, but good control of blood sugar levels, cholesterol and blood pressure minimises this risk.
During the initial stages, retinopathy does not cause any noticeable symptoms. You may not realise that your retina is damaged until the later stages, when your vision becomes affected. Vision loss will probably be permanent at this late stage, which is why diabetic eye screening is so important.
The retina is the light-sensitive layer of cells at the back of the eye. It converts light into electrical signals.
The signals are sent to the brain through the optic nerve and the brain interprets them to produce the images that you see.
To work effectively, the retina needs a constant supply of blood, which it receives through a network of tiny blood vessels.
Over time, a continuously high blood sugar level can cause the blood vessels to narrow, bleed or leak. This damages the retina and stops it from working.
When the blood vessels in the central area of the retina (the macula) are affected, it’s known as diabetic maculopathy.
Read more about the causes of diabetic retinopathy.
Source: NHS England