Why a full exam beats a vision screening
A screening at school, work, or the DMV only asks whether you can read a line of letters. A comprehensive exam looks at the front and back of the eye, measures pressure inside it, checks how the two eyes work together, and compares this year's images to last year's. Plenty of serious problems — glaucoma, early diabetic changes, a thinning retina — cause no blur at all in the beginning. Passing a screening does not rule any of them out.
