Diabetes, caused by the excessive blood sugar, can damage the retina.
Most foods are digested, and broken down into useful nutrients. The body depends on these to grow, function, and fight disease. One of the most important byproducts of this process is sugar. This is essential for the normal function of many organ systems, including the brain. As with other nutrients, too much sugar can be harmful to the delicate tissues of the body. Diabetes is caused by the inability to regulate circulating blood sugar. Usually the body has difficulty producing enough insulin in the pancreas to keep sugar levels normal.
Diabetes damages blood vessels throughout the body. Both kinds of diabetes, Insulin dependent or treated with diet or oral medications, affect the blood vessels. Because diabetes affects the blood, it can cause multi-organ disease. These include kidney damage (nephropathy), nerve damage(neuropathy), and retina damage (retinopathy). Diabetes patients are also susceptible to heart disease and stroke.
Vision will fluctuate with rising and falling blood sugar.
Patients with diabetes report unusual thirst and frequent urination, as well as fatigue. Patients may notice times during the day when their vision blurs. As the disease progresses and hemorrhaging or swelling develops, permanent visual loss may occur.
Spots of blood are often followed within a few days or weeks by greater leakage of blood. In extreme cases, a person will only be able to see light from dark. It may take months or even years for the blood to clear from the inside of the eye. In some cases, the blood will not clear, and may need surgical removal. Large hemorrhages often happen more than once, usually during sleep.
The retina or vitreous cavity in the back of the eye hemorrhages, swells, and scars.
Because diabetes damages the blood vessels, the circulating blood may leak out into the tissue. As the disease progresses, the body tries to grow new blood vessels to supply blood carrying nutrition and oxygen to the damaged retina. These new vessels are more diseased and weaker than the original vessels. Eventually, the retina loses functionality. This happens because of a lack of nutrients and oxygen, and from the resulting scars.
At certain stages, diabetic retinopathy may be treated with a laser to seal the leaking blood vessels.
While laser treatment does not prevent future disease, it can slow the current progression. The treatment takes only minutes. It is usually minimally painful, and only requires numbing the eye with anesthetic drops.
People who are overweight, or who do not exercise, are primarily at risk for diabetes.
Other people at risk include African Americans, those with a family history of diabetes, and pregnant women. If diabetes occurs during childhood, it is classified as Type 1, or juvenile onset diabetes. If diabetes occurs for the first time in adulthood, it is considered as Type 2, or adult onset diabetes.
The best chance for treating diabetes is early detection and prevention.
This comes from careful attention to diet and life style.
Future treatments, including gene therapy and pancreatic islet cell transplants, may allow a diabetic patient to produce enough insulin naturally. This will avoid the need for medications, and prevent the damaging effects of the disease.