Process of emmetropization and development of myopia in schoolchildren

Abstract

Myopia is the most common refractive defect in the world. It begins in the first years of life, due to an interruption in the emmetropization process. These refractive modifications are attributed to changes in axial length, corneal curvature, and lens power, accompanied by a genetic origin, which increases the chances of children to become myopic when their parents have this refractive condition. <em><strong>Objective:</strong></em> To gather information on the process of emmetropization and anatomical changes that cause the development of myopia in schoolchildren. <em><strong>Methodology:</strong></em> A literature review was carried out based on a search of different databases. <em><strong>Results:</strong></em> Anatomical factors can intervene in the successful process of emmetropization however, the amount of axial growth and the initial refractive error are the most influential characteristics, which produce changes in corneal and lens power. The numbers reported in different countries for children under 5 years old are encouraging however, as age increases, prevalence also increases disproportionately, due to genetic and environmental factors. <em><strong>Conclusions:</strong></em> The mechanism of emmetropization is related to the growth of the eyeball: its biometric components are responsible for changes in refraction. These anatomical modifications are mostly influenced by genetic aspects in the first years of life. In the following years, increase is related to environmental and occupational factors.