A yearly dilated eye exam could protect more than just your vision. Problems spotted in the eye are often the first warning of disease elsewhere in the body. Fortunately, eye doctors may be the first to detect several life-threatening conditions.
“We always look for signs of eye disease,” says Katherine Hu, MD, an ophthalmologist at John A. Moran Eye Center. “But subtle, early damage to tiny blood vessels in your eyes can also reveal important clues about what’s going on in your whole body—particularly the brain and heart. Since many diseases have no early symptoms, you could be at risk and not know it.”
That’s one crucial reason why every adult should get a comprehensive eye exam—one in which your eyes are dilated—by age 40 and every year or two after age 65.
A dilated eye exam is simple and painless. Your eye doctor will give you some drops to dilate or widen your pupil. This allows the physician to look at the structures in the back of your eye, including the retina, macula, and optic nerve.
Although numerous conditions beyond eye disease can show up during a dilated eye exam, here are six of the most common:
1. Brain stroke
An ophthalmologist can spot plaque deposits or blood clots in the arteries of the eye. These point to an increased risk for stroke if the deposits reach the brain. A loss of peripheral vision may also be a warning of brain damage caused by a previous stroke.
2. Heart Disease
A special imaging tool used to examine the retina (the light-sensitive tissue at the back of the eye) can reveal whether the blood supply to the retina is reduced or blocked. This could indicate an early symptom of heart disease.
3. Diabetes
Diabetes is a leading cause of vision loss, but signs of diabetic retinopathy, such as tiny blood vessels in the retina leaking yellow fluid, may appear in eye tissue even before a person has been diagnosed. Early detection can help save vision and avoid other serious complications.
4. High Blood Pressure
If left untreated, high blood pressure can lead to heart, brain, and kidney disease. Unusually shaped blood vessels or bleeding in the back of the eye can signal this serious condition.
5. High Cholesterol
Elevated levels of cholesterol can lead to serious health issues, including a life-threatening stroke. If your ophthalmologist sees a yellow or blue ring around the cornea (the clear window on the front of the eye), it may be a sign of high cholesterol. Deposits can also appear in the blood vessels of the retina.
6. Cancer
Your ophthalmologist may be the first to see eye-related skin cancers on the eyelid or the surface of the eye, but cancers in other parts of the body can also be detected in the eye. These include lymphoma, leukemia, and breast cancer. The breast cancer connection may seem unusual, but beyond lymph tissue in the breast area, the most common place in the body for this cancer to spread is to the eyes, where tumors without symptoms may appear.
"The eyes are quite literally a window into your overall health,” Hu says. “In fact, they are the only part of the human body where living blood vessels and nerves are visible by a physician without the need for X-rays or surgery. Findings can offer insightful clues for systemic disease, so be sure to schedule comprehensive eye exams regularly.”