JulEYE – Eye Health Awareness Campaign: Diabetes and Diabetic Retinopathy
Diabetic retinopathy is a complication of diabetes which causes damage to the small blood vessels in the retina of the eye. If left untreated, damage to these blood vessels can cause vision loss and blindness.
All patients with type 1, type 2 and gestational diabetes (diabetes during pregnancy) are at risk of developing diabetic retinopathy. It is recommended that all patients with diabetes have regular eye checks with an ophthalmologist where their pupils are dilated. In its early stages, diabetic retinopathy is a silent disease – there are often no symptoms. Most people with diabetic retinopathy are unaware of any changes to their vision until diabetic retinopathy is quite advanced. Regular eye checks with an ophthalmologist can help promote early detection and prevention of progressive retinal changes caused by diabetic retinopathy before symptoms start.
What causes diabetic retinopathy?
The blood vessels of the retina are the smallest vessels that can be readily examined in the entire body. These small retinal blood vessels are often the first part of the body to show damage due to diabetes.
Diabetic retinopathy is caused by high blood sugar levels over a period of time. Uncontrolled blood sugar levels cause the small retinal blood vessels to leak fluid and blood. Once this damage has occurred, the blood vessel is then unable to deliver nutrients and oxygen to parts of the retina, causing that area of retinal tissue to die.
Diabetic retinopathy can be exacerbated by smoking, high blood pressure and high cholesterol.
Types of diabetic retinopathy:
- Non-proliferative diabetic retinopathy. Non-proliferative diabetic retinopathy is an early stage of diabetic retinopathy where the small blood vessels in the retina leak fluid and blood.
- Macular Oedema. Macular oedema is where the macula, the part of the eye used for central vision, becomes swollen due to leakage of fluid from the retinal blood vessels. Macular oedema can damage the central vision.
- Proliferative retinopathy. Proliferative retinopathy is the advanced form of diabetic retinopathy where new, fragile blood vessels grow on the retina and leak blood very easily. As these vessels grow they can pull on the retina and cause retinal detachment. Proliferative retinopathy can lead to sudden, permanent loss of vision.
How can I prevent diabetic retinopathy?
If you have diabetes, having well-controlled blood sugar levels is the best way to prevent diabetic retinopathy. Maintaining good blood pressure and cholesterol levels, as well as leading a healthy, non-smoking lifestyle will minimise your risk of developing diabetic retinopathy. Having regular eye examinations by an ophthalmologist to examine the health of the retina is paramount in all patients with diabetes.
How will the ophthalmologist look for diabetic retinopathy?
Your ophthalmologist will thoroughly examine the eye for any signs of diabetic retinopathy. This will include a retinal examination where the pupils are dilated to allow a full view of the peripheral retina. The ophthalmologist will use a magnifying lens to enlarge the view of the retina and retinal vessels for close inspection. The retina will be examined for any signs of damage such as leaking blood vessels, changes to the shape of blood vessels, growth of new blood vessels and macular oedema.
The ophthalmologist may also take photographs or scans of the retina using an optical coherence tomographer (OCT). The OCT is a specialised machine which captures high-resolution cross-sections of each cell layer of the retina.
If diabetic retinopathy is suspected, your ophthalmologist may recommend a procedure called fluorescein angiography. Fluorescein angiography is a test where a special dye is injected into the arm. Retinal photographs are taken as the dye travels through the vessels of the retina, showing areas of leaking blood vessels.
Treatment of diabetic retinopathy:
Different treatment options exist depending on the type of diabetic retinopathy.
Diabetic macular oedema can be treated with focal laser, grid laser, or the intravitreal injection of medicines into the eye.
Proliferative diabetic retinopathy:
Proliferative diabetic retinopathy is usually treated with a type of laser called panretinal photocoagulation, whereby laser is applied across the ischaemic retina to discourage the further growth of abnormal fragile blood vessels in the eye. Complications such as vitreous haemorrhage (bleeding into the cavity at the back of the eye) or tractional retinal detachment may require treatment with vitrectomy surgery.
If you have diabetes and would like to have a diabetic eye check, please call Sydney Ophthalmic Specialists to book an appointment with our retinal specialist, Dr Daniel Polya. Phone (02) 9241 2913.