If you’re planning to visit an eye care expert for an eye exam, the illnesses or health conditions that can be detected include: High blood pressure, Heart disease, Diabetes, Rheumatoid arthritis, Thyroid disorder, Parkinson’s disease, Cancer, Multiple sclerosis, Lyme disease, Vitamin A deficiency, Vascular disease, Sickle cell disease, Giant cell arteritis, Cataracts, Glaucoma.