When most of us think of “perfect” vision, we think of 20/20.
We assume that if we have 20/20, our visual system function is normal. If we don’t have 20/20, we need a lens correction to restore our vision to 20/20 – then, our visual system function has been restored to normal. In fact, this is not true.
And what does 20/20 mean, anyway? Over 100 years ago, a Dr. Snellen determined (by the best scientific methods of the day) the smallest target size a human eye could see. This target size came to be labeled (in the United States) a size 20 letter at a distance 20 feet from the eye. Thus, 20/20 means you can see a size 20 letter at 20 feet away. So, 20/40 means you can see a given letter size at 20 feet at what a person with 20/20 can see at 40 feet. Sound confusing? It is!!!!!!
Thus, 20/20 is a measure of visual acuity (clarity) at a 20 foot distance. Visual acuity is important, but there are other vision skills that can have a significant negative effect if not working properly.
If a child is struggling in school, make sure Binocular Vision Function (the ability of the two eyes to team and coordinate together), and the ability to understand or get meaning from the 20/20 visual input is being assessed in your child's vision evaluation.
At The Eye Clinic, a Visual Perceptual Assessment or Visual Skills Assessment measures Binocular (both eyes) function, as well as
Visual Motor Guidance ( eye hand coordination), Ocular Motility (eye tracking), Accommodation (eye focusing), Vergence (eye alignment) and Visual Information Processing/Visual Perception abilities are documented. From these findings, treatment options are discussed with each patient and/or family members.?