Refractive errors in childhood

The eye is a living optical system, the components of which change throughout life. This optical system focuses images of objects on the retina, which are then transmitted to the visual cortex of the brain to be interpreted as vision. If the optics of the system are flawed, as in errors of refraction, the image is blurred. Symptoms of poor vision and asthenopia result, and in childhood, amblyopia can also occur, making refractive errors in childhood more complex than in adult patients. In addition, children may not be able to participate fully in the examination, leaving diagnosis and treatment up to the objective measurements and experience of the examiner. This chapter will deal with how the eye refracts light to produce images on the retina, the most common errors of refraction in childhood, and how to evaluate and manage these errors, including philosophies of treatment for different age groups and different magnitudes and types of refractive error. In addition, special types of refractive errors which require further work-up will be discussed.