Diabetes related eye conditions including Diabetic Retinopathy

This page contains a summary of our information on diabetes-related eye conditions. To read our full information, download our Understanding diabetic retinopathy booklet, which is accredited by the Royal College of Ophthalmologists:

There is treatment for most of the eye problems caused by diabetes. However, it’s important these problems are picked up as soon as possible, as treatment is more effective when given early. You can look after your eyes by:

• having your eyes checked regularly by your optometrist (optician)
• attending diabetic eye screening which can pick up any changes before they affect your sight.

Diabetic eye screening

Regular diabetic eye screening is essential in reducing the risks diabetic retinopathy can pose to your sight. You may not be aware that anything has changed inside your eye until the damage has been done. Diabetic eye screening helps to prevent blindness in most people who are at risk, so if you’ve not had this type of test, ask your GP or diabetic clinic as soon as possible.

NHS diabetic eye screening is offered to people with diabetes who are aged 12 years or older.

When you are first diagnosed with diabetes, your GP should arrange for you to have your initial diabetic eye screening. After this, you’ll be screened as often as is needed. Screening may take place:

• at your GP surgery, your local hospital, optometrist’s practice, or another nearby clinic
• every year or every two years. If diabetic retinopathy was not found at your last 2 tests, you’ll be invited every 2 years. Everyone else will be screened at more regular intervals.

Annual eye examinations with an optometrist

Your diabetic eye screening test doesn’t replace your regular eye test with your optometrist. Screening only looks for changes at the back of your eyes caused by your diabetes. Your optometrist will check for other eye conditions as well. That’s why it’s important to have both tests as often as you’re advised.

NHS eye tests are free for people with diabetes. Some optometrists may take a photograph of the back of your eyes as part of your eye examination, but this does not replace your diabetic eye screening. Having both tests gives the best chance of spotting any changes early. This means treatment can start as soon as it is needed to protect your sight.

Not everyone who has diabetes gets eye problems. Your diabetes may not cause any changes to your vision, especially if your blood sugar levels are controlled. However, people with type 1 diabetes are more at risk of diabetic eye problems than those with type 2.

When diabetes does affect the eyes, it can do so in several ways:

An unstable glasses prescription

• The changes in blood sugar can affect the natural lens inside your eye, especially when your blood sugar levels are not well controlled.
• This can cause blurry vision which can change during the day or from day to day, depending on your blood sugar level.
• This can make your glasses prescription variable and unreliable.
• Sometimes, these changes can be the first sign of diabetes, and you may not yet be diagnosed.
• When your blood glucose becomes better managed, your vision usually settles, but this can take a month or two.
• Your optometrist may suggest ways to manage in the meantime. It is best to wait until your blood sugar and vision are stable before buying new prescription glasses.

Other eye conditions

There may be an increased risk of other eye conditions when you have diabetes, including:

• cataract – a clouding of the lens inside the eye which can develop at an earlier age in people with diabetes
• glaucoma – damage to the optic nerve caused by the pressure inside the eye
• retinal vessel occlusion – when a blood vessel in the retina becomes blocked
• conditions affecting the cornea (the clear front window of the eye) and the tear film (causing dry eye)
• problems with the muscles controlling eye movements which can cause double vision.

Diabetic retinopathy

Over time, raised blood sugar levels can damage retinal blood vessels. Blood vessels can become leaky, blocked, or grow incorrectly. These changes are known as diabetic retinopathy, and they affect how well the retina works.

There are different stages of diabetic retinopathy, and these relate to how much retinal damage there is, and which part of the retina is involved.

Not all diabetic retinopathy requires immediate treatment. If you do need treatment for your diabetic retinopathy, you will be referred to a hospital eye clinic. The ophthalmologist should explain:

• the treatment options available to you
• the advantages and disadvantages of treatment
• the possible side effects of treatment.

Ask your ophthalmologist any questions or concerns you might have about treatment.

Background diabetic retinopathy

Diabetes causes the smallest retinal blood vessels called capillaries to become weakened initially. They may bleed or leak slightly, and these minor changes are known as background retinopathy. Your sight is not usually affected at this point.

You will not require any treatment, but your eyes will need to be monitored yearly to make sure your retinopathy doesn’t progress and get worse.

Pre-proliferative diabetic retinopathy

If background retinopathy does get worse, more retinal blood vessels become damaged or blocked. If these changes happen over a large area of your retina, it will have an insufficient blood supply (ischaemia). Ischaemia means the retinal cells will have insufficient oxygen to work properly. These changes are known as pre‑proliferative diabetic retinopathy.

You will not usually notice too many changes to your vision at this stage. However, it’s important your eyes are examined more often to check the retinal ischaemia does not increase.

You’ll be monitored by your local diabetic eye screening team or an ophthalmologist. This is to ensure your pre-proliferative retinopathy does not get worse. Usually, this will involve more retinal photographs and an OCT scan of your retina or examination by an ophthalmologist. Your check-ups will be between three and 12 months apart depending on the retinal changes found and the risk your retinopathy could worsen.

Proliferative retinopathy

Not everyone with diabetes will develop proliferative diabetic retinopathy but it is more common in people with type 1 diabetes than in those with type 2.

If ischaemia damages your retina, it causes areas of sight loss where your retina cannot work properly. As retinal ischaemia increases, the body tries to make up for the lack of oxygen by growing new blood vessels inside the eye. This may be on the retinal surface or into the clear vitreous gel just in front of the retina. This new blood vessel growth is known as neovascularisation. Unfortunately, these new vessels are weak, so they can bleed easily which can affect your sight. These changes are known as proliferative diabetic retinopathy, and treatment is needed at this stage to help protect your sight.

Treatment is offered when retinal changes are still developing (active proliferative diabetic retinopathy). Your vision may still be very good, as initially, your retinopathy may have very little effect on your sight. You may not understand why you need any treatment at all. However, it’s important to treat neovascularisation early on to reduce the risk of a greater sight loss over time.

Treatment for proliferative retinopathy includes:

• laser treatment (photocoagulation)
• anti-VEGF injections (rarely).

Laser treatment (photocoagulation)

Laser treatment, known as PRP or pan-retinal laser, aims to shrink the growth of new blood vessels. The aim of this treatment is not to make your sight better. It aims to stabilise your condition and protect your vision from becoming a lot worse. Unfortunately, it does not stabilise the condition for everyone.

What will my sight be like after laser treatment?

In the short‑term, laser treatment can temporarily affect your sight because of the brightness of the laser beam and the dilating drops that are used. Therefore, you should not drive yourself to your appointment but arrange alternative transport instead.

The following short-term effects on sight are usually more common after PRP than focal laser treatment:

• Your vision can be reduced for an hour or two after the treatment.
• You can feel “dazzled” or feel like your vision has become darker for some time after your treatment.
• You can temporarily see black spots or have black areas in your vision.
• You may have some flashing lights in your vision after a long session of laser treatment.

All these effects should get better after a few hours. You may find that wearing sunglasses immediately after your treatment helps to reduce glare.

In the longer term, laser treatment can have more lasting effects on your vision. This may mean:

• your peripheral vision may be slightly worse
• your colour perception and your night vision may be affected
• occasionally, your central vision may not be as good as before, so reading may be more difficult for a few days.

These side effects can make it seem like your sight is worse than it was before, and this can be frustrating. While laser treatment does not make your vision better, it does aim to prevent your vision from more serious changes over time. A greater loss of sight is more likely in the long term if treatment is not given.

Although laser treatment can seem to affect your sight, these effects should not continue to progress after your treatment. It’s important you contact your eye clinic or attend A&E immediately if, after your treatment:

• you notice a new shower of floaters (a lot of new dots floating in your vision)
• your eyesight continues to get worse
• your pain worsens or persists for more than a few hours, despite taking painkillers.

Yes, it can, and the risks increase if your proliferative retinopathy is not treated. These complications can include:

• Vitreous haemorrhage (bleed). This happens when there is a bleed into the vitreous gel in front of the retina. This can reduce or totally obscure your vision in the affected eye, and can affect your vision quite quickly. With time, the blood may be reabsorbed into your body, and your vision may improve. However, if you’re told that you need treatment to clear the blood from inside the eye, you’ll be offered surgery called vitrectomy.
• Retinal detachment. If proliferative diabetic retinopathy worsens, scar tissue can develop which can pull and distort the retina. This can sometimes cause the retina to detach from the back of the eye and can lead to more severe sight loss. Retinal detachment is also usually treated with vitrectomy surgery.
• Glaucoma. Advanced ischaemia in the eye can lead to further new blood vessel growth over the iris, the tissue giving your eye colour, and the internal drainage channels which maintain eye pressure. Your eye pressure can increase; this is called neovascular glaucoma. If new blood vessels are growing on your iris, it’s likely you’ll be offered laser treatment to your retina.

The macula is the central, most sensitive part of the retina. Diabetic retinopathy at the macula is called diabetic maculopathy. Most forms of maculopathy do not require treatment. The condition is just monitored every 6-9 months with an OCT scan by your local diabetic eye screening team.

If the blood vessels near the macula are leaky, fluid can build up and cause macular swelling. This is called diabetic macular oedema (DMO). This is usually a more advanced form of diabetic maculopathy which requires treatment.

If you need treatment, you'll be referred to a hospital eye clinic. Treatment can include:

• macular/focal laser treatment
• anti-VEGF injections
• steroid implant.

Your ophthalmologist will explain which of these treatments are suitable for you and the advantages and disadvantages of each option.

Anti-VEGF injections

Anti‑VEGF stands for anti‑vascular endothelial growth factor, and it is given as an injection into the eye.

Anti-VEGF treatment:

• reduces the leakiness of existing blood vessels
• reduces further progression of the retinopathy
• can reduce your macular oedema to stabilise your vision. Some people notice some improvement in their vision.

The anti‑VEGF drug is injected through the white of your eye into the vitreous gel inside your eye. You will need a course of injections over several months.

Steroid implants

A steroid implant might be suggested if your macula has not responded to anti‑VEGF injections, or if anti‑VEGF treatment is not suitable for you. A steroid implant can be injected into your eye. This slowly releases small amounts of steroid to help control the swelling at the macula and help improve your sight.

You may be treated using an implant every 6 months or with one that can stay in your eye for up to three years. The implant eventually dissolves so it does not need to be removed. Your eye pressure may need to be monitored if you have a steroid implant after a few months.

Your ophthalmologist will be able to tell you whether this treatment would be suitable for you and how often your implant treatment would be needed.

If your blood sugar levels are continually high, there’s a greater risk of blood vessel damage and more serious diabetic retinopathy developing over time.

There is also evidence to suggest that the risk of diabetic retinopathy can increase if you lower your blood sugar levels too quickly after they’ve been high. Therefore, it's important to work with your diabetes healthcare team to reduce your blood sugar levels gradually.

The risk of developing serious eye problems is lower if you keep your blood sugar well controlled. Looking after other aspects of your health is also important, such as managing your blood pressure and cholesterol.

There are things you can do to help control your risk of developing retinopathy or stop it getting worse. These include doing your best to:

• keep your blood glucose well controlled
• control your blood pressure well
• control your cholesterol level
• keep as fit as you can with regular exercise and a healthy diet to help maintain a healthy weight
• give up smoking
• attend regular diabetic eye screening and optometrist appointments as advised.

Unfortunately, there are some factors that you cannot control. You’re more at risk of developing some form of retinopathy the longer you’ve had diabetes. Some people still develop more serious diabetic retinopathy, even when they do all they can to lower the risks.

If you have a diabetic eye condition that is picked up early, you may not experience much of a change to your vision. However, some people may have sight loss due to diabetes. With the right support, you can live confidently and independently with your condition. You may not need all this support right now, but you can access further support at any time you need it.

There is more information about the following topics on the links below:

• Employment support
• Assistive technology
• Emotional support and counselling
• Independent living
• Eye care liaison officer (ECLO)

Making the most of your sight

If your diabetes has affected your sight, there are ways you can make the most of your remaining vision. This may mean making things bigger, using brighter lighting or using colour to make things easier to see.

Download our Making the most of your sight booklet (PDF)

Download our Making the most of your sight booklet (Word)

A low vision assessment

A low vision assessment can help you make the most of your vision. A low vision practitioner can explore visual aids or techniques that can help you. This might be with magnifying glasses or aids, or by helping you learn ways of using your vision, called vision strategies. Ask your eye clinic or optometrist about having a low vision assessment.

Managing your diabetes when you have sight loss

If you have sight loss, it can be difficult to access some of the day-to-day devices that are used to manage your diabetes effectively. If you are having difficulties managing your diabetes because of your sight loss, speak to your healthcare team to find out if they can suggest more accessible alternatives for you, such as an audible or talking device.

Useful contacts

Diabetes UK is the leading charity who supports and connects those affected by diabetes.

Watch our videos about managing your diabetes with your diet and managing your diabetes when you have sight loss.