You’ve received a letter asking you to attend an eye appointment for diabetic retinopathy screening. You may be a bit confused, wondering not only what diabetic retinopathy is, but why you’re being asked to test for it. Could there be something wrong with your eyes that you weren’t aware of?

If you have diabetes, it is advised that you attend eye screenings regularly, because you are at increased risk of certain conditions. Receiving a letter doesn’t necessarily mean there is already something wrong, but instead that your doctor wants to monitor your condition to make sure any issues are picked up and dealt with promptly.

We’ve put together an overview of what you can expect from your appointment and how you can best prepare for it.

What is diabetic retinopathy? Why am I being screened for it?

In people with diabetes, diabetic retinopathy occurs due to damage to the small blood vessels in the retina — a structure in the back of the eye where images are formed. If left untreated, the condition can advance and even lead to blindness. However, it is preventable, and the risk of severe vision loss can be decreased through early detection and interventions.

Diabetic retinopathy screening looks for specific changes in the retina, which may be early signs of damage. Being able to detect these signs early is why it’s so important to attend your eye screening appointment1. If you have diabetes and have not had this test done in over a year, you should contact your GP or Specsavers to arrange one.

What is diabetic retinal screening?

Diabetic retinal screening is a surveillance test which is typically performed annually for people with diabetes over the age of 12. During the test, a picture is taken of the back of the eyes (retina) to check for any changes caused by diabetes. The goal is to detect these changes and start treatment before they affect vision: diabetic retinopathy often goes unnoticed until it causes vision loss. The test is non-invasive and painless.

How should I prepare for my appointment?

Your diabetic eye screening will usually be in the eye department of a hospital or a local eye screening service (the NHS have a service finder). Additionally, in certain parts of the country, Specsavers also offer this service. You can find out if you’re near a store that offers this service here. If you wear glasses, you should bring these to the appointment. If you use contact lenses, bring them and their solution along as well. It’s advisable to bring a pair of sunglasses to wear on the way home, as your pupils will be dilated for the test, so you may be more sensitive to light. You’ll also need someone to drive you home as your vision may remain blurry for several hours after the screening, at least until your pupils return to their normal size2. You can eat and drink normally before and after the screening.

What happens during diabetic retinopathy screening?

You’ll first be asked to read some letters on an eye chart. Next, drops will be put into your eyes to dilate your pupils. This allows more light to go into the eye, which makes it easier for the examiner to see the optic nerve and retina clearly and completely and to take a good photograph. The dilating eye drops may sting slightly. It should take around 15 minutes for the drops to take effect.

Once your pupils are adequately dilated, you will be asked to look into a piece of equipment that is essentially a camera. Photos will be taken of the back of your eyes. This is a non-invasive test and will not cause any pain, although there will be a bright flash when the picture is taken3.

When will I get my diabetic eye screening result?

The results of your screening will not be available immediately and you’ll receive a letter with the results from your diabetic screening service. This can typically take around four to six weeks.

In diabetics, chronically high blood sugar can damage the tiny blood vessels in the retina. The clinician who reviews your comprehensive dilated eye exam will look for signs of these changes. These include microaneurysms (tiny swellings) and distortions in the blood vessels, haemorrhages, blockage of the blood supply to some parts of the retina and, in advanced stages, a proliferation (increase) of new blood vessels in response to the blockages. These new blood vessels are fragile and have a propensity to leak and bleed, which can lead to further complications such as scar formation and retinal detachment4.

You will get one of three diabetic retinopathy screening results3:

  • No retinopathy — No changes are detected. Return in a year for another test.
  • Background retinopathy — Small changes are detected, but your eyesight is not affected. Follow your doctor’s recommendations to prevent further eye damage. Return in one year for another screening.
  • Referable retinopathy — Diabetes has caused damage to the eyes and your vision may be affected. You will be referred to a specialist for further advice. Screening tests may be required more often than annually, and you may need to start treatment for your eye damage.

Still not sure what to expect from a diabetic retinopathy screening? Learn more about diabetic retinopathy or book an appointment with a Specsavers optometrist, who will be happy to answer your questions.

References

  1. Garg, S, and Davis Richard M. (2009). Diabetic Retinopathy Screening Update. American Diabetes Association Clinical Diabetes. 2009 Oct; 27(4): 140-145. [Online]. Available at: https://clinical.diabetesjournals.org/content/27/4/140 [Accessed 20 August 2019]
  2. Diabetes.co.uk. (no date). Diabetic Retinopathy Screening and Tests. [Online]. Available at: https://www.diabetes.co.uk/diabetes-complications/retinopathy-screening.html [Accessed 20 August 2019]
  3. NHS Diabetic Eye Screening. (no date). What Happens. [Online]. Available at: https://www.nhs.uk/conditions/diabetic-eye-screening/what-happens/ [Accessed 20 August 2019]
  4. National Eye Institute. (no date). Facts About Diabetic Eye Disease. [Online]. Available at: https://nei.nih.gov/health/diabetic/retinopathy [Accessed 20 August 2019]