Purpose To compare the effects of two combined treatments, corneal collagen crosslinking (CXL) and insertion of intrastromal ring segments (ISRS), for the treatment of keratoconus, using a biomechanical model of the keratoconic cornea
Methods Numerical simulations of both treatments are performed using a biomechanical model of a human keratoconic cornea. Then, simulations of the combination of the two treatments are performed: first CXL and afterwards, ISRS insertion; firs ISCRS insertion and afterwards, CXL.
Results After the numerical simulation, the following effects are observed: the CXL causes a stiffening of the corneal tissue; the insertion of ISRS induces a flattening of the central area of the cornea causing a hyperopic effect and a decrease of the anterior chamber depth (ACD), as our clinical outcomes confirm. The insertion of ISRS achieve higher effect when the CXL treatment is previously performed.
Conclusion The combination of the two treatments, collagen CXL and ISRS insertion, achieve a regularization of the shape of the cornea. According to the outcomes of numerical simulation, collagen CXL must be performed before the insertion of the ISRS in order to achieve better results.