Having a high blood sugar level over a prolonged time can weaken and damage the tiny blood vessels in the retina.
This Can Result In Problems Which Include:
- Small swellings of blood vessels known as microaneurysms.
- Small haemorrhages or bleeds from damage to blood vessels.
- Blockages may occur in blood vessels, cutting off the blood and oxygen supply to small sections of the retina.
- New abnormal blood vessels may grow from damaged vessels. This is called proliferative retinopathy. These new vessels are delicate and can bleed easily.
The leaks, bleeds and blocked blood vessels have the potential to damage the cells of the retina. In some severe cases, blood vessels can bleed into the centre of the eye resulting in vision damage.
Most people with diabetic retinopathy do not have any symptoms. However, left untreated, diabetic retinopathy can gradually become worse and lead to blindness. Diabetic retinopathy is the most common cause of blindness in people of working age in the UK.
If you suffer from diabetes, it is vital to have annual eye checks.
Initial symptoms that may occur include blurred vision, seeing floaters and flashes, or even having a sudden loss of vision.
Different Parts Of The Retina Can Be Affected
The macula is the small part of the retina in the centre at the back of the eye where you focus your vision. When you look at an object, light is focused on the macula. The central and most important part of the macula is called the fovea. The outer part of the retina is used for peripheral vision.
Retinopathy can affect the macula, the outer part of the retina, or both. It is much more serious if the macula is affected.
Severity Of The Retinopathy
Retinopathy tends to develop gradually, often becoming worse over a number of years. Some of the varying degrees of retinopathy are:
- Background retinopathy does not affect your sight. There will be some tiny leaks of fluid or blood (microaneurysms) in various parts of the retina. When examined these can be seen as tiny dots and blots on the retina.
- Pre-proliferative retinopathy is more extensive than background retinopathy. There are signs of restricted blood flow, however new blood vessels have not yet begun to appear.
- Maculopathy is when there is some damage to your macula.
- Proliferative retinopathy occurs when the damaged blood vessels in the retina produce chemicals called growth factors. These chemicals can cause new blood vessels to grow (proliferate) from the damaged ones. This is the body’s attempt to repair the damage. However, the new blood vessels are delicate, and can bleed very easily, obscuring your vision. In this type of retinopathy, without treatment, vision is likely to become badly affected. If the proliferative retinopathy remains untreated it may become severe. Many abnormal new blood vessels may block the drainage channels in your eye, causing glaucoma, or the retina to detach from the back of the eye.
The effects of retinopathy may vary in each eye. If you have high blood pressure in addition to diabetes, the severity of retinopathy may progress at a quicker rate.
Retinopathy is common in people with diabetes, though more common with type 1 diabetes.
Risk factors for diabetic retinopathy include:
- Duration of diabetes. The longer you have had diabetes, the higher your risk level. For those who have had diabetes for less than 5 years, the risk is low. Around 90% of people who have had diabetes for longer than 30 years can be affected with retinopathy.
- High blood pressure. If your blood pressure is not well-controlled, your risk of developing retinopathy will increase.
- Nephropathy (kidney disease). Having kidney disease as a result of your diabetes has been linked with worsening retinopathy.
- Pregnancy. Being pregnant may make retinopathy worsen, especially if your blood sugar (glucose) is not managed properly.
- Other risk factors include smoking, obesity and high cholesterol.
Treatment can prevent blindness and loss of vision in most cases. If you have diabetes, it is crucial that you have regular eye checks to detect any retinopathy before your vision becomes badly affected. You should have your eyes check at least once a year.
To examine your eyes properly you will have drops put into your eyes to dilate (widen) your pupils as much as possible. The drops may blur your vision for up to 6 hours so it is important to make alternative travel arrangements and not drive to and from the appointment.
Another test that can be done is a fluorescein angiogram. A special dye is injected into one of the veins in your arm where it will make it’s way to the blood vessels in your eye. A special camera is then used to show any swollen, leaking or abnormal blood vessels.
If you are found to have no or only mild signs of retinopathy and your vision is not affected, then you may simply be invited back for another screening in 12 months’ time. The retinopathy may never progress to more serious forms, particularly if you control your diabetes and blood pressure. If more severe changes are detected, you may be referred to an eye specialist for a more thorough examination, and treatment if necessary.
If you have mild diabetic retinopathy then you will not usually require any treatment other than controlling any other risk factors (for example, blood pressure, glucose and cholesterol levels).
Laser treatment is mainly used if you have new vessels growing (proliferative retinopathy), or if any type of retinopathy is affecting the macula. The laser is powerful enough to make tiny burns on whatever it is focused on and is accurate enough to target even very tiny abnormal blood vessels. The laser treatment can seal leaks from blood vessels, and stop new vessels from growing further. In some cases several hundred burns may be needed to treat retinopathy.
Treatment usually works well to prevent retinopathy getting worse, and often prevents loss of vision, or blindness. However, this treatment cannot restore vision that is already lost.
After your laser treatment you may find that your sight becomes dim or blurred. This will normally improve in the coming few days.
Other eye operations may be needed if you have a bleed into the vitreous humour or have a detached retina. An operation might also be needed if the laser treatment has been unsuccessful.
Our Appointments Team have a dedicated and caring approach to finding you the earliest appointment possible with the best specialist.
If you do not have a GP, then we have an in-house private GP practice that you can use. Alternatively we can suggest the most appropriate course of action for you to take, given your location and individual circumstance.
If you have medical insurance (e.g. Bupa, Axa PPP, Norwich Union), you will need to contact your insurer to get authorisation for any treatment and, in most cases, you will require a referral letter from your GP.