Ambliopia em crianças: Classificação, triagem e avaliação

Abstract

Introduction: Amblyopia is a functional reduction in visual acuity caused by abnormal visual development early in life. It is a secondary consequence of early visual disturbance from strabismus or other amblyopia-inducing conditions during the critical period for visual development. Objectives: discuss amblyopia in children and its classification, screening and evaluation. Methodology: Integrative literature review based on scientific databases from Scielo, PubMed and VHL, from January to April 2024, with the descriptors "Amblyopia", "Child", AND "Classification".  Articles from 2019-2024 (total 34) were included, excluding other criteria and choosing 5 full articles. Results and Discussion: Amblyopia is classified into three main types based on the underlying condition that induces amblyopia: strabismus, caused by abnormal alignment of the eyes; refractive, caused by unequal focus between the eyes or severe uncorrected refractive error in both eyes; ; deprivation, caused by structural abnormalities of the eye that obscure incoming images. All children <5 years of age should undergo routine vision screening to detect amblyopia. Early detection and treatment of amblyopia improves the prognosis for normal vision development. Screening includes vision risk assessment at every health maintenance visit and vision screening at three, four, and five years of age. Amblyopia should be suspected if vision in the two eyes is unequal or if the child has an amblyopia-inducing condition (e.g., strabismus, asymmetric refractive error, cataract, ptosis). The test used to diagnose amblyopia depends on the child's age. In pre-verbal children, asymmetry of vision may be indicated by an abnormal fixation reflex or occlusion objection test. In older children, asymmetric vision is detected through formal visual acuity testing. Children with suspected amblyopia should be referred to an ophthalmologist or optometrist who is appropriately trained and experienced in treating children. In pre-verbal children, asymmetry of vision may be indicated by an abnormal fixation reflex or occlusion objection test. In older children, asymmetric vision is detected through formal visual acuity testing. Children with suspected amblyopia should be referred to an ophthalmologist or optometrist who is appropriately trained and experienced in treating children. Criteria for referral include: visual acuity worse than 20/40 in a child 3 to 5 years of age or worse than 20/30 in a child ≥6 years, visual acuity difference of ≥2 lines between the eyes on a chart standard vision (e.g., 20/30 in the left eye and 20/40 in the right); abnormal eye alignment (i.e. strabismus); abnormal red reflex; asymmetry of vision (eye preference;) unilateral ptosis or other lesions that threaten the visual axis (e.g., eyelid hemangioma. Conclusion: Amblyopia is the functional reduction in visual acuity caused by abnormal visual development early in life. It is a secondary consequence of early visual disturbance during the critical period for visual development.