The eyes are not only our window to the world, but are the window into diabetes. Early signs of diabetes can sometimes be identified through the eyes. Abnormally high or low levels of blood sugar can cause changes in the shape of the eye lens, and this can impair your ability to focus and see clearly.
When diabetes is left untreated, uncontrolled blood glucose can cause abnormalities that develop in the eye, known collectively as diabetic retinopathy, said Daniel Casper, MD, PhD, professor of ophthalmology at Columbia University Irving Medical Center at the Vagelos College of Physicians & Surgeons in New York City. “Most cases do not result in vision problems; however, if left untreated, other more serious effects may occur, including the growth of new blood vessels in the retina.”
Retinal swelling, known as macular edema, can also occur and degrade vision. If these changes go undetected or untreated, progressive vision loss and possibly even blindness may result. “Most diabetes-related vision loss can be avoided through routine eye exams that identify the presence of diabetic retinopathy, and allow for timely treatment options if necessary,” said Casper.
The symptoms of early diabetic retinopathy may not be obvious, but as the condition advances, some tell-tale signs can usually be detected. Through a dilated eye exam, eye doctors can identify retinal bleeding, swelling or the development of new, abnormal vessels. According to the Mayo Clinic, symptoms of diabetic retinopathy may include:
• small dots, spots or lines appearing in your vision (“floaters”),
• blurred vision,
• fluctuating vision,
• impaired color vision,
• dark or empty areas in your vision, and
• general vision loss.
These are non-specific signs; however, and may be seen in other eye conditions as well. In early retinopathy, tight control of glucose, blood pressure, cholesterol and avoidance of tobacco are the mainstays to slow or prevent progression. Laser treatment, surgery and medications are the most common means used to treat advanced diabetic retinopathy.
Diabetic macular edema
Commonly caused by diabetic retinopathy, diabetic macular edema is the accumulation of fluid in an area of the central retina called the macula, which is responsible for the clearest vision. Symptoms of macular edema are usually blurring or distortion of central vision. Diabetic macular edema is usually associated with persistent, poorly controlled diabetes, severe high blood pressure or use of tobacco. Primary treatment includes injections of medications and laser procedures to reduce fluid leakage and macular swelling.
Preventing vision loss
Early identification of diabetic retinopathy is key to preventing irreversible damage. At minimum, a yearly dilated eye exam, performed by an ophthalmologist, is recommended. This takes about 30 to 60 minutes, on average. In addition to an annual eye exam, the National Institutes of Health (NIH) recommends five ways to maintain good vision, including: taking prescribed medications, maintaining a healthy weight, adding physical activity to your daily routine, controlling blood sugar, blood pressure and cholesterol and kicking the smoking habit. “All of these recommended steps may help to protect eyes from potential problems from diabetes in the future,” explained Casper.