Diabetes and Your Eyes
Diabetic eye disease, caused by diabetes, is a leading cause of blindness and vision loss. Because of the high risk for eye disease, all people with diabetes 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.
What is Diabetic Retinopathy?
Diabetic retinopathy is damage to the retina caused by complications of diabetes. The retina is highly penetrated with small blood vessels and capillaries that can leak if damaged from diabetes. With prolonged elevation of blood sugar, the vascular lining of the retina’s blood vessels become damaged rendering them leaky. If fluid accumulates in the central retina or macula, vision loss results.
If poor retinal circulation results from diabetes, the retina will become oxygen depleted resulting in the growth of abnormal new blood vessels, a condition known as neovascularization. Neovascular blood vessels are friable and prone to leak, resulting in bleeding within the eye that can be excessive. People with diabetes have a significantly higher risk of blindness than the general population. Diabetic eye disease is a complication of diabetes and a leading cause of blindness. There are no symptoms in the early stages of diabetic eye disease. The prevalence of diabetic retinopathy in people with diabetes is high. The good news is that diabetic eye disease can be treated and your vision can be saved — if you catch it early – through a dilated eye exam. Don’t wait for symptoms. If you have diabetes, get a dilated eye exam at least once a year. It doesn’t hurt – it’s easy – and it could save your sight.
What If I Develop Retinopathy?
If you develop retinopathy, the doctors at The Vision Care Center will know when and how to treat the damage to your eyes. Often laser surgery (using a special beam of light) is performed to treat the damaged blood vessels inside the eye. People with diabetes are 40% more likely to suffer from glaucoma than people without diabetes. The longer someone has had diabetes, the more common glaucoma is. Risk also increases with age.
Many people without diabetes get cataracts, but people with diabetes are 60% more likely to develop this eye condition. People with diabetes also tend to get cataracts at a younger age and have them progress faster. Diabetic retinopathy is a general term for all disorders of the retina caused by diabetes.
Nonproliferative vs Proliferative
There are two major types of retinopathy: non-proliferative and proliferative. Non-proliferative retinopathy is the most common form of retinopathy. In non-proliferative retinopathy, capillaries in the back of the eye balloon and form pouches. Non-proliferative retinopathy can move through three stages (mild, moderate, and severe), as more blood vessels become blocked. Although retinopathy does not usually cause vision loss at this stage, the capillary walls may lose their ability to control the passage of substances between the blood and the retina. Fluid can leak into the part of the eye where focusing occurs, the macula. When the macula swells with fluid, a condition called macula edema, vision blurs and can be lost entirely. Although non-proliferative retinopathy usually does not require treatment, macular edema must be treated, but fortunately treatment is usually effective at stopping and sometimes reversing vision loss.
In some people, retinopathy progresses after several years to the more serious proliferative retinopathy. In this form, the blood vessels are so damaged they close off. In response, new blood vessels start growing in the retina. These new vessels are weak and can leak blood, blocking vision, which is a condition called vitreous hemorrhage. The new blood vessels can also cause scar tissue to grow. After the scar tissue shrinks, it can distort the retina or pull it out of place – this is called retinal detachment. Your retina can be badly damaged before you notice any change in vision. Most people with nonproliferative retinopathy have no symptoms. Even with proliferative retinopathy, the more dangerous form, people sometimes have no symptoms until it is too late to treat them. For this reason, you should have your eyes examined regularly by an eye care professional.
Huge strides have been made in the treatment of diabetic retinopathy. 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.
In photocoagulation, your ophthalmologist at The Vision Care Center makes tiny burns on the retina with a special laser. These burns seal the blood vessels and stop them from growing and leaking. In scatter photocoagulation (also called panretinal photocoagulation), your ophthalmologist makes hundreds of burns in a polka-dot pattern on two or more occasions. 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. This treatment is also used for some kinds of glaucoma. Side effects of scatter photocoagulation are usually minor. They include several days of blurred vision after each treatment and possible loss of side (peripheral) vision.
In focal photocoagulation, your ophthalmologist at The Vision Care Center 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. The next option is vitrectomy, which is surgery to remove scar tissue and cloudy fluid from inside the eye. The earlier the operation occurs, the more likely it is to be successful. When the goal of the operation is to remove blood from the eye, it usually works. Reattaching a retina to the eye is much harder and works in only about half the cases.