by guest author Tim Harwood, Optometrist

The first thing to say is that it is important to have regular eye tests regardless of whether you have diabetes or not. However, it is especially important for diabetics to have regular eye tests and it is recommended that you attend for an examination annually. For non-diabetic sufferers an eye test is generally advised every two years. Diabetic retinopathy is one of the leading causes of blindness in the U.S and many of those suffering from it could have prevented their loss of vision by simply attending for regular eye tests.

What is diabetic retinopathy?

Diabetic retinopathy is a disease of the blood vessels within the retina which is located at the back of our eyes. The retina is the single most important component of our eyes, as it is responsible for collecting all the information that is required for us to see. Within the retina there are many thousands of blood vessels and diabetic retinopathy results in these blood vessels become weakened and damaged.  Approximately 40 percent of diabetics will have diabetic retinopathy to some degree, although many of these will not experience any visual loss.

How does diabetic retinopathy cause visual loss?

There are a few different ways vision loss can occur and it depends on the severity of the diabetic retinopathy. The most common ways are as follows:

-Leaking blood vessels: Due the damage of the blood vessel walls it is common for blood and fluid to leak from them. If these blood vessels are supplying the central part of the vision then significant vision loss can occur.
-Blocked blood vessels: The damage to the blood vessels can cause them to become blocked; meaning areas of the retina will not receiving the blood (and therefore oxygen) that they require to function properly. If this blood supply is cut off for long enough, the retina will ‘die’ in that area, causing a permanent loss of vision.
-Growth of new blood vessels: The area of the retina that is being starved of blood sends out signals for the eye to produce new blood vessels in an attempt to re-supply it with blood and oxygen. These new blood vessels that grow are extremely fragile and weak and consequently are more likely to leak, causing further damage to the retina.

What’s the best way to stop diabetic retinopathy?

There are a few ways to reduce your risk of developing diabetic retinopathy and they are as follows:

-Regular eye tests: The single most important thing you can do is have an eye test every year. In the early stages diabetic retinopathy you may have no symptoms and this is especially the case if it is not affecting your central vision. You diabetic retinopathy could therefore be developing to a sight threatening level without you realizing it.
-Control blood sugar levels: The importance of this cannot be underestimated as good control will dramatically reduce your risks of developing diabetic retinopathy. Put simply, the longer your blood sugar levels are not stable the greater the risk of developing the disease.
-Control blood pressure: There is evidence to suggest that controlling your blood pressure will also reduce your chances of developing any problems.
-Control cholesterol: In addition to controlling blood pressure, it is very important that your cholesterol is also controlled.
-Quit smoking: Some studies have shown that smoking can increase your chances of developing diabetic retinopathy.

Can diabetic retinopathy be treated?

The answer is yes but with limited success and is dependent on the extent of the disease. If the diabetic retinopathy is monitored regularly, treatment can be performed to stop the disease progressing. Prevention is most definitely better than cure as once your vision has been damaged it is very difficult to get it back. The following are the most likely treatments:

-Control blood sugar levels: The first thing to do is to ensure your blood sugar, blood pressure and cholesterol are well controlled. This will prevent further damage and also mean you will respond better to treatment.
-Laser treatment: This is generally only required if your retinopathy is particularly bad and involves your eye specialist applying around 1000 laser burns to your damaged retinal blood vessels. This causes these blood vessels to close up and therefore stop leaking.

It is important to realise that this not the laser eye surgery that your hear about that corrects your vision. Laser eye surgery is performed on your cornea which is on the outer surface of your eye, whereas diabetic laser treatment is carried out on your retina at the back of the eye.

In summary, diabetic retinopathy is an extremely serious eye disease which if not treated can often lead to blindness. The longer you have had diabetes and the less controlled your blood sugar levels are, the more likely you are to develop the condition. Having said this, if you have regular eye tests and are vigilant in your control of your blood sugar levels, your blood pressure and your cholesterol there is a good chance that it will not affect your vision.