Complications of Diabetes

Diabetic Retinopathy

What is Diabetic Retinopathy?

A view of a normal Retina (Image courtesy of DESS):

A normal retina

Diabetic retinopathy is a condition affecting blood vessels in the back layer of the eye (the retina) of people with diabetes. The retina is the sensing membrane of the eye which contains important elements for sight. The retina turns light into nerve signals which are sent along the optic nerve to the brain. These tiny blood vessels become weak and break down, resulting in small bleeds and leakage of other substances into this vital layer of the eye. Once damaged the changes are irreversible and loss of sight ensues.

Diabetic retinopathy is a major cause of vision loss and blindness. It is largely preventable  and if detected early treatable. At worst it can cause blindness and glaucoma.

Who is at risk for Retinopathy?

Retinopathy is usually a complication of longstanding diabetes. All people with diabetes are at risk - those with type 1 diabetes as well as type 2. However, in some people it can appear within the first year or two after the onset of the disease and in others retinopathy may be one of the first signs that they have diabetes. The longer you have diabetes, the greater the risk of retinopathy. It is estimated that more than 40% of people who have had diabetes for 15 years or more have some evidence of retinal involvement.

During pregnancy retinopathy may progress rapidly. It is important that pregnant women with diabetes have regular eye examinations.

Can it be prevented?

Yes. Prevention is certainly the best answer for diabetic retinopathy. It is important that you have an eye examination once a year as part of your diabetes care. This may take the form of your doctor looking at the back of your eye using an instrument called an ophthalmoscope or in some centres, taking a retinal photograph using a digital eye camera. This allows detection of the earliest changes of diabetic retinopathy and offers good prospects of preserving sight. With early treatment blindness is preventable.

Retinopathy can develop silently. At first you may notice no changes at all in your vision. Over the years it may progress

What symptoms should I look for?

Many patients with diabetes have no symptoms whatsoever.

Damage to the retina may give you some of the following symptoms

  • spots or 'floaters'
  • pain
  • blurred vision

Why does retinopathy cause loss of vision?

  • Retinopathy causes abundant growth of tiny new blood vessels within the retina. These blood vessels are very fragile and tend to break down easily causing small bleeds. These blood leaks may result in loss of sight.
  • Over a period of time with frequent bleeds, fibrosis or scar tissue forms which can tug on the retina and cause 'retinal detachment'
  • A large bleed can occur into the central chamber of the eye (known as the vitreous). This blood may have to be surgically removed by a process called a 'vitrectomy'

Where can I get more information?



Dr Nishan Wijenaike, Consultant Physician
West Suffolk Hospital Diabetes Service
October 2002