Diabetes is a condition in which the body does not produce enough insulin or does not respond properly to the insulin that is produced. This causes blood sugar levels to be chronically high. Patients who have diabetes can develop a number of different complications due to the high blood glucose, including problems with the eyes.
Short-Term
One of the earliest symptoms of diabetes is temporary blurring of the vision, MayoClinic.com notes. The high levels of sugar in the blood can affect the composition of the liquid portion of the eye, also known as the aqueous humor. These changes can alter the properties of the aqueous humor, resulting in trouble focusing on objects and blurred vision. This blurred vision is not permanent, however, and will resolve with time.
Non-Proliferative Retinopathy
Diabetic retinopathy is a long-term complication that stems from diabetes, the American Diabetes Association explains. The most common form of diabetic retinopathy is known as non-proliferative diabetic retinopathy. With this condition, small blood vessels in the back of the eye become blocked and balloon. This can cause fluid from the blood vessels to leak into the eye, resulting in a condition known as macular edema, which can cause blurred vision and loss of vision. Macular edema requires treatment to prevent and reverse vision loss.
Proliferative Retinopathy
Over time, patients with diabetes can also develop a condition known as proliferative retinopathy. With this condition, new blood vessels form in the eye to take the place of ones that have become blocked. These new blood vessels tend to leak blood into the eye, resulting in a condition known as vitreous hemorrhage. The new blood vessels may also trigger the growth of scar tissue, which can pull the retina out of place or distort it, leading to vision loss. The damage to the retina can be permanent and result in loss of some or all of the visual field.
Other Disorders
People who have diabetes also have a higher risk of developing glaucoma and cataracts. Glaucoma is a condition in which the fluid in the eye does not drain properly, causing the pressure in the eye to gradually increase. This can cause damage to the optic nerve, resulting in loss of peripheral vision. Cataracts are a condition in which the lens of the eye, which focuses images, becomes cloudy, resulting in trouble seeing. Although cataracts occur in many people without diabetes, diabetics are more likely to develop them and tend to do so at an earlier age.
Prevention
There are two main strategies for preventing eye problems associated with diabetes: The first is to keep the patient's blood sugar well controlled with medications and lifestyle changes. If blood sugar levels do not get too high, there is less of a chance that eye problems will result. Additionally, frequent eye exams, which can help identify eye problems before they become severe and result in noticeable vision loss, are recommended by the National Eye Institute
