Sometimes, chronic or life-threatening conditions like heart disease, stroke, diabetes, high blood pressure or cancer can be identified during an eye exam. A symptom as common as blurred vision can lead to many of these diagnoses.

“I have seen patients come in with blurred vision, thinking they just need glasses,” said Judy Hoggatt, MD, an ophthalmologist at the Froedtert & MCW Eye Institute. “But during the exam, when I can see the blood vessels, nerves and retinal tissue, there can be evidence of abnormalities tied to conditions that are outside the eye.”

Swelling or bleeding inside the eye can be important clues and are visible to an ophthalmologist by microscope.

“I once saw a patient with hemorrhage patterns consistent with poor blood flow to the carotid artery,” Dr. Hoggatt said. “Because of this pattern, I listened to his carotid artery, and it appeared there could be some obstruction in flow. This patient ended up needing a carotid endarterectomy, a procedure that removes built-up plaque from the artery. He needed blood flow to the brain restored, or he was at risk of a stroke.”

A person may also experience “mini-strokes,” which are momentary lacks of blood flow to the brain. In this case, blurred vision may last for 10 to 15 minutes and then resolve.

“Sometimes, loss of vision can be the first sign of poor circulation,” Dr. Hoggatt said.

Blurred vision is also a symptom of retinopathy, or damage to the blood vessels in the retina. The retina is a layer of light-sensitive tissue in the back of the eye. Cells in the retina send signals to the brain via the optic nerve. Retinopathy often presents with leaky blood vessels. The leaked fluid creates a murky layer, making it difficult for light rays to pass through the retina. High blood pressure can cause hypertensive retinopathy and high blood sugar can cause diabetic retinopathy. Both conditions can progress to blindness.

During an eye exam, the ophthalmologist checks the optic nerve, the nerve that sends messages from the eye to brain. Multiple sclerosis (MS) causes inflammation in the optic nerve, which leads to a condition called optic neuritis. One of the earliest signs of MS is blurred vision. A growth in the optic nerve could be yet another reason for blurred vision. The tumor could be benign or cancerous.

“Routine eye exams are the best way to avoid vision problems and can sometimes detect life-threatening diseases,” Dr. Hoggatt said.

The Froedtert & MCW Eye Institute recommends that adults who have no previous signs of eye problems and are not in a high-risk group for eye disease receive a comprehensive eye exam from an ophthalmologist, according to the following recommendations of the American Academy of Ophthalmology:

Age Frequecy of Examination
65 or older Every 1 or 2 years
40 to 64 Every 2 to 4 years
30 to 39 At least twice during period
20 to 29 At least once during period

If you wear contact lenses, see your eye specialist annually.

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Eye Care and Vision