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Four-year changes in corneal biomechanical properties in children

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

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

Clinical & Experimental Optometry
|March 20, 2019
PubMed

Insights

Corneal biomechanical parameters like corneal hysteresis and corneal resistance factor decrease with age in children, with greater reductions observed in males. Axial elongation and corneal flattening are linked to these reductions.

Area of Science:

  • Ophthalmology
  • Biomedical Engineering
  • Pediatric Optometry

Background:

  • Investigating longitudinal changes in corneal biomechanics in children is crucial for understanding ocular development.
  • Previous studies have primarily focused on cross-sectional data, limiting insight into age-related biomechanical alterations.

Purpose of the Study:

  • To track four-year changes in corneal biomechanical parameters in Iranian children aged 7-11.
  • To explore correlations between these biomechanical changes and optical components.

Main Methods:

  • A four-year prospective cohort study involving 468 children initially evaluated in 2012 and re-evaluated in 2016-2017.
  • Utilized multi-stage stratified cluster sampling, cycloplegic refraction, biometry (LENSTAR/BioGraph), and ocular response analyzer (ORA) for corneal biomechanical assessment.
  • Assessed corneal hysteresis (CH), corneal resistance factor (CRF), peak areas (p1, p2), and irregularity indices (A, B).

Main Results:

  • Most biomechanical parameters, including CH and CRF, decreased over the four years, with mean changes of 0.68±0.16 mmHg.
  • Males exhibited greater reductions in CH and CRF compared to females.
  • Older age groups, particularly 11-year-olds, showed the most significant decreases in CH and CRF, while CH and CRF were directly related to corneal power and inversely related to axial length.

Conclusions:

  • Age and sex significantly influence ocular response analyzer (ORA) parameters in children.
  • Progressive age is associated with reduced corneal biomechanical properties, more pronounced in males.
  • Axial elongation and corneal flattening contribute to decreased corneal hysteresis and corneal resistance factor.
Abstract

Keywords:
agebiomechanicschildrencorneahysteresisresistance factorsex

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