Carly Lindner, a Williamstown, N.J., sixth-grader, knew something was wrong when her vision started getting blurry and she was seeing blue dots. But her health was otherwise completely fine.
Carly's mom, Stefanie, took her to the Walmart Vision Center, where a doctor realized that she had severe swelling of the optic nerve. After taking Carly to the hospital, a brain tumor was fortunately ruled out. But doctors did find excess fluid around the brain -- a condition that they said could have potentially left Carly blind.
"That's why it's, you know, important too for people to come in every year or two for an eye exam because, even if you don't have any symptoms -- she had very mild symptoms -- there can be something very serious going on," the doctor at Walmart who first helped Carly, Dr. Nazmul Hasan, told Fox.
Indeed, according to the American Optometric Association, risk-free or asymptomatic kids ages 6 to 18 should get an eye exam before first grade, and then every two years after that. Kids who are considered at high risk for vision problems should get an annual checkup. Asymptomatic adults between age 18 and 60, on the other hand, should get an eye checkup every two years (or one to two years for at-risk adults), and people ages 61 and older should get an eye checkup once every year.
For more on Carly's story, as well as other health conditions that can be detected via eye exams, watch the video above.