Vision screening

What is screening?

“Screening is the systematic application of a test or inquiry identifying individuals at sufficient risk of a specific disorder to benefit from further investigation or direct preventative action, amongst other individuals who have not [yet] sought medical attention.” In ophthalmology, healthy children are impacted primarily by amblyopia, strabismus, cataracts, and uncorrected refractive error. Screening can detect each of these disorders. The need for screening has been recognized by the fact that over 50% of pediatric eye conditions that affect children’s sight are detected by pediatricians or family doctors.

Screening of the visual system is performed by primary care providers at various times during childhood. The disease being screened for depends on the age of the patient. For example, screening for retinopathy of prematurity is performed primarily by pediatric ophthalmologists and retina specialists and is limited to premature neonates who meet certain criteria (see Chapter 44 ). Red reflex testing to screen for media opacities (and potentially high refractive errors) is performed by the primary care provider beginning in the neonatal nursery, and should be performed throughout childhood. However, the primary purpose of this chapter is to discuss the role of screening for amblyopia and its risk factors (strabismus and high refractive error) in preschool children, and for other causes of decreased vision (primarily refractive error) in school-aged children.

When is ophthalmic screening appropriate in the pediatric population?

Some conditions are appropriate to screen for, whereas others are not. Conditions that should be detected by screening generally are of moderate prevalence, have a latent period, have a known treatment, and have a treatment that has a significant benefit. The World Health Organization (WHO) has defined criteria that are important for screening ( Box 105.1 ). Screening for retinopathy of prematurity in at-risk neonates, screening for amblyopia and its risk factors in preschool children, and periodic screening for decreased acuity from refractive error in school all meet the criteria established by the WHO. On the other hand, screening for retinoblastoma in patients without a family history would not meet the WHO criteria because of the low prevalence of the disease in the population, and the relatively long period of time over which the disease could present. Similarly, screening for optic nerve hypoplasia, another rare condition, is also not recommended, because there is a low prevalence of the condition, no latent period, and no treatment.