Do you know that Diabetic Retinopathy is the leading cause of blindness and vision loss?

It is a well-known fact that diabetes is a dangerous and potentially life-threatening disease. What some may not realise is that one of the conditions associated with diabetes is a type of vision loss called diabetic retinopathy. 

The good news is that this complication is treatable, and the best outcomes are usually obtained from an early diagnosis by your ophthalmologist. The most effective ways to protect your vision lie with knowing what to expect and how to treat diabetic retinopathy.

Diabetic retinopathy is one of the leading causes of vision loss worldwide and is the principal cause of impaired vision in patients between 25 and 74 years of age.

This article will provide a detailed explanation of diabetic retinopathy, including its risk factors, symptoms, diagnostic methods, treatment options, and preventive measures to protect your vision.

Diabetic retinopathy (DR) is a common microvascular complication of diabetes. It is a condition that is characterised by a change in the retina’s blood vessels of the eye. 

The retina is a thin layer of tissue that lines the back of the eye on the inside and is located near the optic nerve. It senses light and sends images to your brain for visual recognition. 

The abnormal blood vessel is caused by an increase in blood glucose, which can harm the blood vessels. When these blood vessels thicken, they can develop leaks, which can then lead to vision loss. New blood vessels may also grow, causing further damage. 

Many people who have diabetes have some form of diabetic retinopathy.

There are four stages of diabetic retinopathy, ranging from mild to severe. 

At the initial stages of diabetic retinopathy, your sight loss may not be noticeable or detected. It is only during the late stage that the vision would be affected, at which point the damage to the retina may be irreversible.

Stage 1: Mild non-proliferative retinopathy

At this stage, tiny blood vessels swell in the retina. Some early leakage may take place.

Stage 2: Moderate non-proliferative retinopathy

Some of the blood vessels that feed the retina become blocked. Leaky blood vessels are more likely.

Stage 3: Severe non-proliferative retinopathy

More blood vessels are being blocked, resulting in other areas of the retina not being nourished, leading to areas of the retina not receiving adequate blood flow. 

Without proper blood flow, the retina cannot grow new blood vessels to replace the damaged ones. Signals are then sent to the body to grow new blood vessels.

Stage 4: Proliferative retinopathy

This is when sight loss can occur quickly. This is the advanced stage of the disease. 

Additional new blood vessels will begin to grow in the retina, but they will be fragile and abnormal, causing blurred vision, severe sight loss, or blindness.

Note: The advanced stages of diabetic retinopathy can also increase your vulnerability to developing other eye conditions, such as a detached retina, which requires surgery, and glaucoma.

Anyone who has diabetes is at risk for developing diabetic retinopathy, but not all diabetics will be affected. 

In the early stages of diabetes, you may not notice any change in your vision. But by the time you notice vision change, your eyes may already be damaged by the disease.

Risk of developing the eye condition can increase as a result of:

• Duration of diabetes — the longer you have diabetes, the greater your risk of developing diabetic retinopathy
• Poor control of your blood sugar level
• High blood pressure
• High cholesterol
• Pregnancy
• Tobacco use

Diabetic eye disease is a leading cause of blindness and vision loss. Because of the high risk for eye disease, all those who are diagnosed with diabetes at age 30 and older should receive an annual dilated eye exam. 

For people with diabetes younger than 30, an annual dilated exam is recommended after they have had diabetes for 5 years. 

Do not wait for symptoms! When left untreated, diabetic retinopathy damages your retina. 

You might not have symptoms in the early stages of diabetic retinopathy. Once symptoms develop, it may be too late to save the vision. 

As the condition progresses, symptoms of diabetic retinopathy may include:

• Spots or dark strings floating in your vision (floaters)
• Blurred vision
• Fluctuating vision
• Impaired colour vision
• Dark or empty areas in your vision
• Vision loss

Note: Diabetic retinopathy usually affects both eyes.

Protect your vision before it’s too late. Schedule an eye exam with Island Hospital specialists today to ensure accurate diagnosis and timely care.

An eye doctor can usually tell if you have diabetic retinopathy during an eye exam. The best way to diagnose diabetic retinopathy is a dilated eye exam. 

During this exam, the physician places drops in the eyes to make the pupils dilate (open widely) to allow a better view of the inside of the eye, especially the retinal tissue.

Your eye doctor will look for:

• Swelling in the retina that threatens vision (diabetic macular edema)
• Evidence of poor retinal blood vessel circulation (retinal ischemia)
• Abnormal blood vessels that may predict an increased risk of developing new blood vessels
• New blood vessels or scar tissue on the surface of the retina (proliferative diabetic retinopathy)

Regular dilated eye exams by an ophthalmologist are important, especially for those who are at a higher risk for diabetic retinopathy or diabetes. 

If you are over age 50, an exam every 1 to 2 years is a good idea so the physician can look for signs of diabetes or diabetic retinopathy before any vision loss has occurred. 

In addition to checking for signs of diabetic eye disease, a comprehensive dilated eye exam will evaluate your vision needs for:

• Corrective lenses
• Eye pressure (looking for glaucoma)
• The “front” of the eye (eyelids, cornea, checking for dry eyes)
• Lens (looking for cataracts)
• The retina and vitreous (full examination)

Treatments such as scatter photocoagulation, focal photocoagulation, and vitrectomy prevent blindness in most people. 

The sooner retinopathy is diagnosed, the more likely these treatments will be successful. The best results occur when sight is normal.

At your comprehensive eye exam, the ophthalmologist will carefully view the retina through your dilated pupil. The doctor will look for:

• Any currently leaking blood vessels
• Evidence of past vessel leakage. 

These problems are often seen before you notice any visual symptoms. Early detection and treatment are critical to preventing vision loss.

• Nonproliferative diabetic retinopathy
  People with nonproliferative diabetic retinopathy may not need treatment. However, they should be closely followed up by an eye doctor.

• Proliferative diabetic retinopathy
  For patients with proliferative diabetic retinopathy, treatment may be recommended, and though treatment usually does not reverse damage that has already occurred, it can help keep the disease from getting worse. Once your eye doctor notices new blood vessels growing in your retina (neovascularisation) or you develop macular edema, treatment is usually needed.

1. Laser eye surgery (Photocoagulation)

Your ophthalmologist makes tiny burns on the retina with a special laser. These burns seal the blood vessels and stop them from growing and leaking. 

• Scatter photocoagulation (panretinal photocoagulation)

In scatter photocoagulation (also called panretinal photocoagulation), your ophthalmologist makes hundreds of burns in a polka-dot pattern on two or more occasions. 

It treats a large area of your retina and can shrink the abnormal blood vessels. 

Scatter coagulation reduces the risk of blindness from vitreous hemorrhage or detachment of the retina – but it only works before bleeding or detachment has progressed very far. 

During the procedure, if severe bleeding is found inside the eye (vitreous haemorrhage), laser may not be possible.

This treatment is also used for some kinds of glaucoma. Side effects of scatter photocoagulation are usually minor.

• Focal laser photocoagulation 

Your ophthalmologist aims the laser precisely at leaking blood vessels in the macula. This procedure does not cure blurry vision caused by macular edema. But it does keep it from getting worse. 

When the retina has already detached or a lot of blood has leaked into the eye, photocoagulation is no longer useful.

2. Vitrectomy 

Vitrectomy is a surgical procedure required to clear the bleeding in the eye. This procedure is performed by a vitreo-retinal surgeon, a highly trained ophthalmologist.

3. Anti-angiogenic drug injections

In diabetic eye disease, abnormal blood vessels develop that can break, bleed, and leak fluid. If left untreated, these damaged blood vessels can result in a rapid and severe loss of vision. 

The most effective treatments to date for this blood vessel damage are the anti-angiogenic drug injections, such as:

• Avastin (bevacizumab)
• Accentrix (ranibizumab)
• Eylea (aflibercept)
• Ozurdex (dexamethasone implant). 

These drugs are given as injections in the eye.