Many people don't understand the difference between a vision screening and a comprehensive eye examination conducted by a licensed eye care professional. The differences are significant and can have a lasting impact on the long term visual prognosis of an individual.
Vision screening programs are intended to help identify people (particularly children) who display gross vision problems that may profoundly impair sight and the ability to learn effectively in the classroom. However, these screenings are typically done by volunteers or staff members improperly trained in visual acuity assessment (i.e reading an eye chart). In fact, one fourth to one third of school aged children have a vision disorder that went undetected at their school or pediatrician's vision screening. Moreover, vision screenings don't test for proper eye movement, focusing ability, or visual cognitive processing. Even more critical is the fact that vision screenings cannot diagnose an eye or vision problem, and don't have the ability to check for eye diseases.
Comprehensive eye and vision examinations, on the other hand, can only be conducted by an eye doctor (optometrist or ophthalmologist) with the specialized training needed to make a definitive diagnosis and to provide a requisite treatment plan. Many of the specialized instruments and equipment used in an eye exam are not available in a vision screening program. The testing procedures typically done in a comprehensive eye exam include measurement of visual acuity at distance and near, determination of refractive state (myopia, hyperopia, astigmatism, presbyopia), binocular vision assessment (depth perception and fusion), color vision, focusing ability, eye tracking skills, visual processing, and a thorough eye health assessment.
Vision screenings, because they are misunderstood by parents and patients alike, can provide a false sense of security, and therefore should never be used as a substitute for a professional eye examination. And remember to have your eyes examined at least once a year.
Yours in Eye Health,
Kevin Crosier, OD
