Your eyes aren't just the windows to your soul — they can also reveal valuable information about your general health beyond whether you need glasses, including: diabetes, heart disease, and even cancer. It is not unusual for people to come in for an eye exam just to check their eyesight and then have certain health issues or predispositions picked up by the optometrist.
Eye Exams and Your Health
Eye examinations can help doctors detect general health conditions early enough to intervene. Advanced screenings enable eye doctors to better predict cardiovascular incidents like stroke, and possibly detect signs of mental changes such as Alzheimer's. Read below to learn how eye exams can unveil a whole lot more than just eye health.
Brain Cancer & Stroke
Because of the similarities between the blood vessels in the eye and brain, an eye doctor can occasionally detect an issue taking place in the brain by examining the blood vessels in the eyes. If swelling or shadows in the eye is observed, it may indicate a serious condition in the brain, like a tumor, or clots that might result in a stroke.
Diabetes can cause damage to the blood vessels in the retina at the back of the eye, resulting in Diabetic Retinopathy (DR) and Diabetic Macular Edema (DME). If an optometrist detects leaky blood vessels in the eye, the patient would be advised to see a doctor to help control their blood sugar. Changes are gradual, and they start before visual symptoms are noticed. The earlier diabetic eye disease is managed, the better the chances are of preserving eyesight.
High blood pressure, characterized by having too much pressure in the blood vessels, can be detected during an eye exam, sometimes even before it's diagnosed by your regular doctor. The damaged blood vessels lead to swelling, hemorrhages, and leaking — all of which can be observed in the eyes. According to the CDC, hypertension "the silent killer" affects nearly 1 in 3 adults, and up to a whopping 20% of those don't even know they have it. So early detection at an eye doctor's evaluation can be truly life-saving.
Eye exams can also detect a buildup of cholesterol. High cholesterol is among the easiest conditions to spot during a complete eye exam, as the cholesterol deposits manifest on the front of the eye, appearing as a thin, gray rim around the cornea. It can also be detected in the retina by assessing artery and vein patterns.
These deposits may indicate the current or future development of Retinal Blood Vessel Occlusion, a condition where blockages restrict blood flow to the back of the eye, causing temporary or permanent vision loss.
In some cases, heart conditions associated with a buildup of plaque in the carotid artery in the heart can also lead to deposits that clog the ocular arteries in the eye. If an optometrist detects such changes to the vascular structure at the back of the eye, he or she will typically recommend going to a specialist.
Multiple Sclerosis (MS)
Sudden vision loss may be attributed to Multiple Sclerosis (MS). While the optometrist can recognize signs indicating the presence of MS, such as the color and appearance of the optic nerve, such cases will be referred for further testing to confirm the diagnosis.
Thyroid disease can make itself apparent through the eyes in several ways. The thyroid gland controls the hormones that regulate tear production so some thyroid disorders can cause dry eye disease. Additionally, overactive thyroid (hyperthyroidism) can make the extraocular muscles enlarge and stiffen, causing bulging eyes — an indicator of Graves' disease.
Systemic conditions that are associated with inflammation in the body can have an inflammatory effect on the eyes. Uveitis, for example, causes eye inflammation, redness, and blurred vision, and tends to occur in people with lupus, rheumatoid arthritis, and other autoimmune diseases.
Breast cancer, leukemia, and other metastatic cancers are occasionally discovered during an eye evaluation. In addition to brain cancer mentioned above, melanoma and basal cell carcinoma (skin cancer) can be detected, and eye doctors can also diagnose lymphoma and other eye tumors. Eye exams save lives.
What the Future Holds
Recent studies show that a non-invasive and precise imaging device called Octa (optical coherence tomography angiography) can signal the presence of eye changes associated with Alzheimer's disease. Because the retina is in many ways an extension of the brain, the altered blood vessels at the back of the eye offer a glimpse into the changes taking place within the brain.
Parkinson's Disease can often be misdiagnosed as its early symptoms are characteristic of other conditions. Research has shown that subtle eye tremors, an early Parkinson's marker, could be detectable using advanced eye exam technology. One day soon, practitioners may send patients to an eye doctor to test for this and other diseases.
Your Eye Doctor's Appointment Could Change Your Life
So the next time you visit Dr. Kara at Bay College Optometric Centre in Downtown Toronto, remember that a comprehensive eye exam can do more than determine your eyeglasses or contacts prescription. Dr. Kara can evaluate your eyes for existing or potential health issues, and communicate them to your primary care physician for the best possible care. By knowing that you're at risk for a certain disease, you can take precautions early on and manage the condition as needed. After all, an ounce of prevention is worth a pound of cure.