Diabetic retinopathy is the most common form of diabetic eye disease. Diabetic retinopathy usually only affects people who have had diabetes (diagnosed or undiagnosed) for a significant number of years.
Retinopathy can affect all diabetics and becomes particularly dangerous, increasing the risk of blindness, if it is left untreated.
The risk of developing diabetic retinopathy is known to increase with age as well with less well controlled blood sugar and blood pressure level.
According to the NHS, 1,280 new cases of blindness caused by diabetic retinopathy are reported each year in England alone, while a further 4,200 people in the country are thought to be at risk of retinopathy-related vision loss.
All people with diabetes should have a dilated eye examination at least once every year to check for diabetic retinopathy.
What is diabetic retinopathy?
Diabetic retinopathy occurs when changes in blood glucose levels cause changes in retinal blood vessels. In some cases, these vessels will swell up (macular oedema) and leak fluid into the rear of the eye.
In other cases, abnormal blood vessels will grow on the surface of the retina.
Unless treated, diabetic retinopathy can gradually become more serious and progress from ‘background retinopathy’ to seriously affecting vision and can lead to blindness.
Diabetic retinopathy includes 3 different types:
What are the symptoms of diabetic retinopathy?
Like many conditions of this nature, the early stages of diabetic retinopathy may occur without symptoms and without pain. An actual influence on the vision will not occur until the disease advances.
Macular oedema can result from maculopathy and affect vision occurs if leaking fluid causes the macular to swell. New vessels on the retina can prompt bleeding, which can also block vision in some cases.
Symptoms may only become noticeable once the disease advances, but the typical symptoms of retinopathy to look out for include:
- Sudden changes in vision / blurred vision
- Eye floaters and spots
- Double vision
- Eye pain
Read more about the symptoms of diabetic retinopathy.
How is diabetic retinopathy caused?
Diabetic retinopathy is caused by prolonged high blood glucose levels. Over time, high sugar glucose levels can weaken and damage the small blood vessels within the retina.
This may cause haemorrhages, exudates and even swelling of the retina.
This then starves the retina of oxygen, and abnormal vessels may grow. Good blood glucose control helps to lower diabetes retinopathy risks.
Am I at risk from diabetic retinopathy?
Diabetic retinopathy risk factors include the following.
If any of the below affect you it’s worth having an retinopathy screening examination as quickly as possible.
- Poor blood glucose control
- Protein in urine
- High blood pressure
- Prolonged diabetes
- Raised fats (triglycerides) in the blood
Anyone suffering from diabetes faces the risk of developing diabetic retinopathy and other diabetes complications.
The longer a person has diabetes, the greater the risk of developing diabetic retinopathy becomes. However, keeping blood glucose levels well controlled can help to significantly slow down the development of retinopathy.
People with diabetes should, however, be aware that a rapid improvement in blood glucose levels can lead to a worsening of retinopathy. A rapid improvement in blood glucose levels in this case is defined as a drop in HbA1c of 30 mmol/mol or 3%.
Retinopathy occurs when blood vessels in the back of the eye, the retina, become damaged. When the blood vessels become damaged they can leak and these leaks can cause dark spots on our vision.
The main causes of retinopathy tend to be sustained high blood glucose levels and high blood pressure as well. Retinopathy can progress over years or decades depending on how good your blood glucose control is.
The good news is that because it takes a long time to develop, it can be spotted before it becomes too serious.
The symptoms of retinopathy tend to come on once retinopathy has been developing for some time. The symptoms present themselves as dark patches on your vision. You may not notice them at first but can be more noticeable if retinopathy is not picked up.
It’s important therefore that you attend your retinopathy screening each year.
People with diabetes should be screened in the UK once each year for retinopathy. A photograph is taken of the eye which allows the specialists to spot any signs of damage that may be present.
Screening appointments mean that the signs can be spotted well in advance of symptoms developing. In the early stages of retinopathy, no treatment is needed but it’s recommended that patients keep good control of their blood sugar levels.
If retinopathy develops laser surgery may be needed. Laser targets the problem blood vessels to prevent them from leaking. Other treatments for advanced retinopathy can include injections or vitrectomy surgery.
Are there any ways to prevent diabetic retinopathy?
Long-term good blood glucose level management helps to prevent diabetes retinopathy and lower the risk of developing it. Heart disease risk factors also affect retinopathy risk and include stopping smoking, having regular blood pressure and cholesterol checks and undergoing regular eye check-ups.
The risk of developing diabetic retinopathy can be lessened through taking the following precautions:
- Taking a dilated eye examination once a year
- Managing diabetes strictly through medicine, insulin, diet and exercise
- Test blood sugar levels regularly
- Test urine for ketone levels regularly
Can diabetic retinopathy be treated?
Laser surgery is often used in the treatment of diabetic eye disease, but each stage of diabetic retinopathy can be treated in a different way.
Background retinopathy has no treatment but patients will need regular eye examinations.
Maculopathy is usually treated with laser treatment (tiny burns that help to prevent new blood vessel growth and improve the nutrient and oxygen supply to the retina).
This is usually painless and has no side effects, but can influence night driving and peripheral vision.
This type of laser treatment for diabetic retinopathy will not improve vision, but it can prevent deterioration. Proliferative retinopathy is also treated with lasers, with a scattering over the whole retina. This destroys the starved area of the retina.
Serious diabetes retinopathy cases may require eye surgery.
This is usually diagnosed due to bleeding in the eye, late-stage proliferative retinopathy or ineffective laser treatment. This type of diabetic retinopathy eye surgery is called vitrectomy.
- Read more on treating retinopathy
Background retinopathy, also known as simple retinopathy, involves tiny swellings in the walls of the blood vessels. Known as blebs, they show up as small dots on the retina and are usually accompanied by yellow patches of exudates (blood proteins).
Background diabetic retinopathy requires regular monitoring by an ophthalmologist. It is therefore important to attend regular retinopathy screening appointments.
The macula is the most well used area of the retina and provides us with our central vision. Maculopathy refers to a progression of background retinopathy into the macular.
This can cause vision problems such as difficulty with reading and or seeing faces in the centre of your vision.
Proliferative retinopathy is an advanced stage of diabetic retinopathy in which the retina becomes blocked causing the growth of abnormal blood vessels.
These can then bleed into the eyes, cause the retina to detach, and seriously damage vision. If left untreated, this can cause blindness. If proliferative retinopathy is regularly monitored and treated, the development of retinopathy can help be limited and more severe damage may be prevented.