Assessment of corneal biomechanical properties and intraocular pressure with the Ocular Response Analyzer in childhood myopia

Background/aims The authors estimated the association between corneal biomechanical properties and axial length in myopic children and verified the relationship between axial length and intraocular pressure (IOP).

Methods This cross-sectional study included 126 eyes of 63 children, aged 12.02±3.19 years. Corneal hysteresis (CH), corneal resistance factor (CRF), central corneal thickness (CCT) and IOP were recorded with the Reichert Ocular Response Analyzer. Axial length (AL) and anterior chamber depth (ACD) were measured by the IOLMaster, whereas corneal curvature was measured by an autorefractor.

Results In multivariable mixed model analysis, CH correlated significantly with AL (p<0.0001), ACD (p=0.044) and CCT (p<0.0001), but not with curvature; CRF correlated significantly with AL (p=0.004) and CCT (p<0.0001) but not ACD or curvature. The difference in CH between the two eyes of each patient correlated significantly with the difference in the AL between the two eyes (p=0.002). IOP did not correlate with age, gender or AL.

Conclusion Lower CH and CRF were associated with longer AL but not corneal curvature. The association between lower CH and deeper ACD demonstrated the importance of CH as a determinant of ocular biometry in both the anterior and posterior segments. Differences in corneal biomechanical properties may indicate more generalised structural differences between eyes.