Effect of ocular biometric factors on corneal biomechanical properties

To evaluate the effects of ocular biometric variables on corneal biomechanical properties.

A total of 102 eyes of 102 participants were enrolled in this cross-sectional study. The axial length (AL) was determined by an IOL master 500 and measurements of corneal biomechanical properties were performed using Corvis ST, integrated with pentacam results.

Aging and corneal steepening were associated with less corneal deformability and higher movement of the entire eye. Longer AL corresponded with greater deformability and lower corneal viscous damping properties and less whole eye movement (all P-values < 0.05). In contrast to mean keratometry (Mean K) and corneal diameter, anterior chamber depth (ACD) and AL have a significant effect on corneal biomechanical parameters. Corneal biomechanical index (CBI) was not significantly correlated with any of biometric parameters. Stress-strain index (SSI) was significantly correlated with age (r = 0.470), spherical equivalent (SE) (r = 0.537), AL (r = -0.534) and ACD (r = -0.316) (all P-values < 0.001).

In normal individuals, several parameters such as age, ACD, AL and Mean K have a great impact on corneal biomechanical properties; thereby, these effects should be taken into account prior to interpretation of corneal biomechanics, particularly in older ages and eyes with longer AL and steeper cornea.