Causes of Diabetic Retinopathy
Diabetic retinopathy, the most common diabetic eye disease, occurs when blood vessels in the retina change. When blood sugar levels are too high for extended periods of time, it can damage capillaries (tiny blood vessels) that supply blood to the retina. Over time, these blood vessels begin to leak fluids and fats, causing edema (swelling). Eventually, these vessels can close off, called ischemia. In other cases, abnormal new blood vessels grow on the surface of the retina.
Nonproliferative diabetic retinopathy (NPDR)
Nonproliferative diabetic retinopathy (NPDR) is the earliest stage of diabetic retinopathy. With this condition, damaged blood vessels in the retina begin to leak extra fluid and small amounts of blood into the eye. Sometimes, deposits of cholesterol or other fats from the blood may leak into the retina.
Proliferative Diabetic Retinopathy
Proliferative diabetic retinopathy (PDR) occurs when abnormal blood vessels begin to grow on the surface of the retina or optic nerve.The new vessels are also often accompanied by scar tissue that may cause the retina to wrinkle or detach.
Symptoms of Diabetic Retinopathy:
You can have diabetic retinopathy and not be aware of it, since the early stages of diabetic retinopathy often don’t have symptoms. As the disease progresses, diabetic retinopathy symptoms may include:
- Spots, dots or cobweb-like dark strings floating in your vision (called floaters);
- Blurred vision;
- Vision that changes periodically from blurry to clear;
- Blank or dark areas in your field of vision;
- Poor night vision;
- Colors appear washed out or different;
- Vision loss.
Diabetic retinopathy symptoms usually affect both eyes.
Risks of Diabetic Retinopathy
People with diabetes are at risk for developing diabetic retinopathy. The risk decreases after 20 years of having the disease.
You can reduce the risk of developing Diabetic Retinopathy by:
- Keeping your blood sugar under control
- Monitoring your blood pressure
- Maintaining a healthy diet
- Exercising regularly
Treatment of Diabetic Retinopathy
The best treatment for diabetic retinopathy is to prevent it. Strict control of your blood sugar will significantly reduce the long-term risk of vision loss. Treatment usually won’t cure diabetic retinopathy nor does it usually restore normal vision, but it may slow the progression of vision loss. Without treatment, diabetic retinopathy progresses steadily from minimal to severe stages .
Laser procedure does not cure diabetic retinopathy. It helps to prevent further loss of vision. Laser surgery shrinks abnormal new vessels and reduces macular swelling.
In Proliferative DR, the laser is applied to all parts of the retina except the macula (called PRP, or panretinal photocoagulation). This treatment causes abnormal new vessels to shrink and often prevents them from growing in the future. Panretinal laser has proven to be very effective for preventing severe vision loss from vitreous hemorrhage and traction retinal detachment. Multiple laser treatments over time may be necessary.
HbA1c is a lab blood test that shows the average level of blood sugar (glucose) over the previous 3 months. It shows how well you are controlling your diabetes. An HbA1c of 5.6% or less is normal; pre-diabetes: 5.7% to 6.4. If you have diabetes, you and your doctor or nurse will discuss the correct range for you. For many people the goal is to keep your level at or below 6.5 – 7%. If your level is above 7% and you have diabetes, it often means that your is not well controlled. Your target HbA1c should be determined by you and your health care provider. In general, the higher your HbA1c, the higher the risk that you will develop problems such as eye, heart, kidney disease and nerve damage. If your HbA1c stays high for a long period of time, the risk for these problems is even greater.