Cornea biomechanical characteristics measured using the Ocular Response Analyzer in Singapore children

Abstract

Abstract Purpose To determine the corneal biomechanical parameters measured with the Reichert Ocular Response Analyser(ORA) in Singaporean children, and to assess their correlations with refractive error and biometry Methods This was a cross sectional study of 271 subjects from the Singapore Cohort Study of Risk Factors for Myopia(SCORM). Corneal hysteresis (CH), corneal resistance factor(CRF), central corneal thickness(CCT) and intraocular pressure(IOPcc) were measured with the ORA. Spherical equivalent refraction, axial length, height, weight, and blood pressure were measured. Results The mean age of the study population was 13.97±0.89years, the gender distribution was almost equal(138 males,50.9%),and the majority were Chinese.The mean CH and CRF were 11.78±1.55mmHg and 11.81±1.71mmHg. CH and CRF did not vary with age, sex or race. CH and CRF did not vary with myopia (p=0.79;0.83), or axial length (r=‐0.11 and ‐0.05,p=0.08 and 0.40). Multivariate analyses were performed with CH, CRF or CCT as the dependent and age, gender, race, weight, IOPcc, CCT, SE refraction, and corneal curvature as covariates. CH was significantly associated with IOP (beta=‐0.22(95%CI ‐0.27,‐0.17)), CCT (beta=0.03(0.02,0.03)) and corneal curvature (beta=‐1.13(‐2.08,‐0.19)). CRF was significantly associated with IOP, CCT and corneal curvature.(beta=0.08(0.02,0.14);0.03(0.03,0.04) and ‐1.39(‐2.54,‐0.23) respectively). The only factor predictive of decreased CCT was Malay or Indian race compared with Chinese. Conclusion The CH and CRF values in our study on children are slightly higher than in adult studies. CH and CRF are not associated with refractive error or axial length. Flatter corneas are associated with lower CH and CRF readings