Most recent studies classify around two-third of myopia as early onset called juvenile or school myopia, starting between 9 to 11 years of age and development through the early teenage years (Gilmartin B, 2004: Morgen IG et al. 2014).
Usually, infantile myopia has been suggested to be represented by a generally stable refraction status (Blach RK, 1985), whereas in school myopia with modern intensive education, can continue to worse for the next twenty years of life (Medelfart A et al. 1992: Kinge B et al. 1999). Recent studies reported that the increase in the prevalence rates of high myopia only starts to arise after (11-13) years (.Wu JF et al 2013: Xiang F et al 2012). This increase appears to be a consequence of environmental factors, which cause another form of myopia Known as acquired high myopia to differentiate it from a high myopia that has primary genetic factors.
( Xiang F et al 2012). This finding supported by a recent study demonstrating that high myopia in younger groups has strong association with education more than high myopia in older groups (Jonas JB et al. 2016)Nearwork The first suspicion that near work contributes to myopia was raised byKepler in 1611, confirmed by Tscherning in 1882, and later has been consistently demonstrated(Curtin,1985: Owens, 1991).
Several epidemiological studies,examined the association between myopia and near work and have shown positivefinding with some studies (Ip JM et al.2008: Jones-Jordan LA et al.2011: French AN et al. 2013:Gong Y et al. 2014) and othersstudies, reported no relationship (Jones-Jordan LA et al.
2012: Lin Z et al. 2014). Near work appears to be associatedwith myopia among children in Australia and Caucasia (Mutti DO et al. 2002: Ip JM et al.2008) but were notsignificantly associated with the prevalence of myopia in Singaporean children(Saw SM et al. 2006). TheSydney Myopia Study (SMS) which had a stratified random sample a group ofchildren aged 6 and a group aged12, with three years in between for reexamination, they found that children who spent time in reading more than half anhour continuously were more likely to have rapid progression of myopia comparedto those who read for less than half an hour continuously. Furthermore, childrenwho performed near-tasks at distance less than 30 cm were 2.
5 times more likelyto have myopia than those who worked at a longer distance. Similarly, childrenwho enjoy reading for a long time and those who read at a distance > 30 cmwere more likely have a higher degree of myopia (Ip JM, Saw SM et al. 2008). The Singaporecoherent of risk factor of myopia (SCORM) shown that children who read morethan two books per week were around three times more likely to have highermyopic refraction compared with those who read less than two books per week.(Saw SM et al. 2002: Saw SM et al.2006). In contrast, severalstudies have reported that correlations between near work and myopia are notsignificant and consistent as those between education and myopia(Mutti DO et al.
2009).However,associations with near work are frequently reported, and a recent meta-analysishas provided evidence that there is a strong association between near work andmyopia(Huang HM et al. 2015).Public health organization measures are necessary such as that teachersand parents take attention of the potential for urging students to develop goodnear work related behaviors to inhibit the onset and progression of myopia.