Finite Element Analysis of Ring Implantation for Keratoconic Cornea Treatment

Implantation of Intrastromal Corneal Ring Segments(ICRSs) is a surgical method to flatten the anterior cornealsurface which is cone shaped in a keratoconic cornea. In thisstudy, a two-dimensional axis-symmetric Finite Element(FE) model has been developed to analyze the performanceof ICRS for keratoconic cornea treatment. Ocular parts(cornea, limbus and sclera) are modeled with a combinationof hyper-elastic and elastic material properties and triangulargeometry for ICRS (named Ferrara). The performance ofFerrara ring implantation for different implant heights andoptical zones were studied and compared with availableclinical data. It was found that inserting a higher implantswith smaller optical zone has more correction effect onkeratoconus treatment. Moreover, this model is capable ofpredicting the implant performance for different extents ofkeratoconic disease.