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Amblyopia in children: Classification, screening, and evaluation

David K Coats, MD
Evelyn A Paysse, MD
Section Editor
Richard A Saunders, MD
Deputy Editor
Carrie Armsby, MD, MPH


Amblyopia is a functional reduction in visual acuity caused by abnormal visual development early in life. It is the most common cause of pediatric visual impairment, occurring in 1 to 4 percent of children. Early detection of amblyopia and/or amblyopia risk factors improves visual outcomes [1-4]. This is the basis for screening preschool-age children for vision problems and amblyopia (table 1A-B). (See 'Screening' below and "Screening tests in children and adolescents", section on 'Vision screen'.)

The definition, classification, and evaluation for amblyopia is reviewed here. The management and outcome of amblyopia are reviewed separately. (See "Amblyopia in children: Management and outcome".)

Vision assessment, strabismus, and refractive errors in children are also discussed separately:

(See "Visual development and vision assessment in infants and children".)

(See "Evaluation and management of strabismus in children".)

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Literature review current through: Nov 2017. | This topic last updated: Sep 05, 2017.
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