The influence of different factors on corneal biomechanical properties in norm and in progressive keratoconus

Abstract

A prospective study of corneal stiffness parameter of 174 eyes of 174 healthy subjects with different refractions as well as 56 eyes with keratoconus was carried out. The study groups were comparable in age and gender composition. Correlation was performed between corneal stiffness parameter (Stiffness Parameter (SP-A1), minimum corneal thickness (MCT) and biomechanically compensated intraocular pressure (bIOP) determined using Pentacam HR and Corvis ST (OCULUS, Germany), as well as the anteroposterior chamber (APC) value and patient age. Based on multivariate regression analysis, the correlation between corneal stiffness index SPA1, minimum corneal thickness (MCT) and biomechanically compensated IOP (bIOP) in healthy subjects (p = 0.00001, p = 0.005, respectively) as well as in patients with keratoconus (p = 0.00000, p = 0.0032, respectively) was established. Using the obtained data, the tables for determination of corneal stiffness in healthy subjects and patients with different stages of keratoconus, depending on the minimal thickness and level of biomechanically compensated intraocular pressure, were compiled. Application of the tables will allow in practical work to quickly analyze corneal stiffness index which can be used as an important diagnostic criterion in patients with keratectasia.