Diabetic Retinopathy (Diabetes Eye Disease)

The retina is the thin layer at the back of your eye that senses light. It works like the film in a camera: it catches the picture and sends it to your brain.

When blood sugar stays high for a long time, it weakens the walls of the tiny blood vessels in the retina. These vessels can leak fluid or blood, become blocked, or the eye may grow new, weak vessels that bleed easily. This damage is called diabetic retinopathy.

It can affect anyone with type 1 or type 2 diabetes.

Image to add

Diagram of a healthy eye next to an eye with diabetic retinopathy, with labels "Healthy blood vessels" and "Damaged blood vessels bleeding into the retina". Alt text: "A healthy eye compared with an eye with diabetic retinopathy, showing leaking and bleeding blood vessels at the back of the eye."

The stages, in simple words

• Early stage (non-proliferative): small swellings and leaks in the blood vessels. There are usually no symptoms.
• Advanced stage (proliferative): the retina grows new, fragile blood vessels. They can bleed inside the eye or pull on the retina.
• Diabetic macular oedema: fluid builds up in the macula, the centre of the retina we use to read and recognise faces. It can happen at any stage and is the most common reason people with diabetes lose vision.

What causes it?

High blood sugar, over many years, slowly damages the walls of small blood vessels all over the body, including the eyes, kidneys and nerves. High blood pressure and high cholesterol add to this damage. The longer you have diabetes, and the less controlled it is, the more likely the eyes are affected.

Everyone with diabetes is at risk. Your risk is higher if:

• you have had diabetes for many years
• your blood sugar (HbA1c) is often high
• you have high blood pressure
• you have high cholesterol
• you have kidney problems, such as protein in your urine
• you are pregnant and have diabetes
• you smoke

In Brunei: a study of adults with type 2 diabetes found that about 1 in 5 had diabetic retinopathy, and about 1 in 10 had a type that threatens sight. Having diabetes for more than 10 years, an HbA1c above 9%, and protein in the urine were linked to higher risk.

In the early stages you will not feel anything and your vision may be perfect. That is why regular eye screening is so important.

Later, you may notice:

• blurred or changing vision
• dark spots or "floaters" in your vision
• colours looking faded
• dark or empty areas in your vision
• difficulty seeing at night

How the eye check is done

• Retinal photo (eye screening): a quick, painless photo of the back of your eye. In Brunei, some centres now use artificial intelligence (AI) to help read these photos.
• Eye examination with dilating drops: the drops widen your pupil so the doctor can see the retina clearly. Your vision may be blurry and bright for a few hours, so do not drive yourself home.
• OCT scan: a painless scan that checks for swelling in the macula.

How often should I be checked?

• Type 2 diabetes: when you are first diagnosed, then every year (or as your doctor advises).
• Type 1 diabetes: within 5 years of diagnosis, then every year.
• Pregnant, or planning pregnancy: before pregnancy or early in pregnancy, then as advised by your doctor, because the eyes can change quickly during pregnancy.

Ask your doctor or nurse at your health centre or diabetes clinic about your next eye screening.

What can happen?

If it is not found and treated early, diabetic retinopathy can lead to:

• Blurred vision
• Bleeding inside the eye (vitreous haemorrhage), seen as sudden floaters or dark shadows
• Retinal detachment, where the retina is pulled away from the back of the eye
• Neovascular glaucoma, a painful rise in eye pressure
• Permanent blindness

The good news: most serious sight loss from diabetes can be prevented when it is found early and treated on time.

1. Control your sugar, blood pressure and cholesterol. This is the foundation of all treatment and slows the damage.
2. Eye injections (anti-VEGF): medicine is injected into the eye after numbing drops. It reduces swelling and stops abnormal vessels from growing. Usually a course of several injections is needed.
3. Laser treatment: seals leaking vessels or shrinks abnormal new vessels.
4. Steroid injections or implants: for some people with swelling in the macula.
5. Eye surgery (vitrectomy): to remove blood or scar tissue from inside the eye.

Treatment cannot always bring back vision that is already lost, but it can stop it getting worse. The earlier it starts, the better the result.

To prevent or slow down diabetic retinopathy:

• Go for an eye screening every year, even if you see well.
• Keep your blood sugar within your target.
• Keep your blood pressure and cholesterol normal.
• Stop smoking.
• Live healthily: balanced meals, regular exercise, and take your medicines every day.
• See a doctor if your vision changes.

Local updates and Brunei research

• AI eye screening: Jerudong Park Medical Centre (JPMC) launched Brunei's first artificial-intelligence diabetic retinopathy screening service on 24 April 2024. [9]
• How common is it in Brunei? About 1 in 5 adults with type 2 diabetes had diabetic retinopathy (22.6%), and about 1 in 10 had sight-threatening disease (9.7%). [7]
• Awareness in Brunei: a 2025 study looked at how much patients at community eye clinics in Brunei know about diabetic retinopathy. [8]

Go to the Emergency Department the same day if you have:

• sudden loss of vision
• a sudden shower of new floaters or flashes of light
• a dark shadow or "curtain" coming across your vision