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Four-year change in ocular biometric components and refraction in schoolchildren: A cohort study

Hamed Momeni-Moghaddam1, Hassan Hashemi2, Siamak Zarei-Ghanavati3

  • 1Department of Optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran.

Journal of Current Ophthalmology
|July 19, 2019
PubMed

Insights

This study tracked ocular changes in Iranian children over 4 years. Significant myopic shifts and changes in axial length, anterior chamber depth, and lens power were observed, particularly in boys.

Area of Science:

  • Ophthalmology
  • Pediatric Optometry
  • Biometry

Background:

  • Childhood myopia is a growing concern globally.
  • Understanding ocular component changes in children is crucial for myopia management.
  • Longitudinal data on ocular biometry in pediatric populations is essential.

Purpose of the Study:

  • To investigate 4-year changes in ocular biometric and dioptric components in Iranian children aged 7-11 years.
  • To identify potential differences in these changes based on sex.
  • To analyze age-related variations in ocular component development.

Main Methods:

  • A cohort of 468 Iranian children aged 7-11 years was assessed at baseline and after 4 years.
  • Multi-stage stratified cluster sampling ensured representative participant selection.
  • Ocular biometry and cycloplegic refraction were performed using standardized equipment (Topcon autorefractometer, LENSTAR/BioGraph biometer).

Main Results:

  • A significant myopic shift (spherical equivalent) was observed, more pronounced in boys.
  • Axial length and anterior chamber depth increased, while lens thickness and lens power decreased.
  • Changes were generally more significant in boys, with some age-related variations noted.

Conclusions:

  • Ocular biometric components (axial length, anterior chamber depth, lens power, lens thickness) exhibited statistically and clinically significant changes over 4 years.
  • These biometric changes followed a sinus rhythm.
  • The findings highlight important developmental trends in children's eyes, with implications for refractive error progression.
Abstract

Keywords:
AgeAxial lengthBiometryChildrenKeratometryLens powerOcular dioptric componentSex

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