This optical illusion dares you to spot all the hidden faces in just five seconds. Look closely, the answer reveals far more than meets the eye. Did you catch them all?

Fluorescein angiography is a type of eye test used to diagnose retinal conditions. It can also be used as an early way to gauge whether someone might have complications with future treatments of eye ...

Online color blindness tests may give people an idea of whether they may be color blind and if so, which type of color blindness they might have. This information comes from the National Eye Institute ...