Changes in Lens Power in Singapore Chinese Children during Refractive Development

Abstract

Newly developed myopes showed a significantly greater decrease in lens power than other refractive groups, which may be linked to rapid changes in AL and refraction that occur around the onset of myopia.

Distribution of the Crystalline Lens Power In Vivo as a Function of Age

“…15,29 This is in contrast to the positive correlation found in children's eyes, with hypermetropes having higher refractive lens powers than emmetropes or myopes, 34,35 while the current study suggests that emmetropic eyes have significantly higher lens powers than in high myopes or hypermetropes. The positive correlation between lens power and spherical refraction in myopes also 23 (20 eyes, unstretched in vitro using magnetic resonance imaging), Borja et al 7 (51 eyes, stretched in vitro using lens meter), Olsen et al 29 (325 eyes, in vivo using Olsen method and noncyclopleged refraction), Atchison et al 28 (66 eyes, in vivo using phakometry and noncyclopleged refraction), Iribarren et al 30 (1926 eyes, in vivo using Bennett method and cyclopleged refraction), and the current study (1069 eyes, in vivo using Bennett-Rabbetts method and noncyclopleged refraction).…”

Lens power loss in early adulthood

“…The increase in axial thickness can be seen in the follow-up of the current study, and interestingly, although curvatures may be steepening slightly with age in these engineering students, the lens is losing power probably because of changes in its internal structure, as has been discussed before (Iribarren et al 2012). The fact that the lens seems to be losing more power in baseline emmetropes or hyperopes than in myopic subjects is possibly related to the changes seen in lens power loss during myopia development in previous studies (Iribarren et al 2012;Mutti et al 2012).…”

“…A À0.77 dioptres change in 3 years represents a rate of lens power loss of À0.26 dioptres per year, which compares well with the rate of lens power loss in SCORM emmetropic schoolchildren of À0.29 dioptres per year (Iribarren et al 2012). It could then be that the rate of lens power loss does not slow up much after age 10 and is still present during early adult life in subjects prone to develop myopic shifts, like these engineering students in Norway.…”

“…This loss of power compensates for axial elongation in eyes that remain nearly emmetropic during infancy and adolescence. But during school myopia development, the lens has been shown to alter its rate of lens power loss (Iribarren et al 2012;Mutti et al 2012). Three studies in selected groups developing myopia during early adulthood have reported prospectively on myopic shifts and biometry.…”

Axial length growth and the risk of developing myopia in European children

“…1998; Iribarren et al. 2012). In contrast, AL increases during childhood and in the teenage years, leading to myopia if this growth in AL exceeds the eye's focal point (Zadnik et al.…”