Patient-Specific Finite Element Modeling Of Keratoconic Corneas For Predictive Simulation Of The Grosso® Reshaper Implantation
Published 2026 - 44th Congress of the ESCRS
Reference: FP30.02 | Type: Free paper | DOI: 10.82333/c68n-9s33
Authors: Mrs Graziana Maria Ragonese* 1 , Mrs Benedetta Fantaci 2 , Mr Dario Carbonaro 3 , Dr Sandra Suescun Busto 4 , Dr Laura Zahiño Lora 4 , Prof. Dr José Luis Güell 4 , Dr Edoardo Grosso 5 , Mrs Rossella Baldini 5 , Mr Moses Kakanga 5 , Mr Emiliano Lepore 5 , Prof. Diego Gallo 6
1Department of Mechanical and Aerospace Engineering,Politecnico di Torino, PoliToBIOMed Lab,Torino,Italy;Recornea Srl,Trieste,Italy, 2Universidad de Zaragoza,Zaragoza,Spain, 3Department of Mechanical and Aerospace Engineering,Politecnico di Torino, PoliToBIOMed Lab,Torino,Italy;Department of Mechanical, Energy and Management Engineering,University of Calabria,Calabria,Italy, 4Instituto de Microcirugía Ocular (IMO), Miranza Group,Barcelona,Spain, 5Recornea Srl,Trieste,Italy, 6Department of Mechanical and Aerospace Engineering,Politecnico di Torino, PoliToBIOMed Lab,Torino,Italy
Purpose
To develop an accurate framework for the patient-specific digital reconstruction of keratoconic corneas from in vivo data, incorporating stress-free configuration and anisotropic collagen fiber orientation. This method is currently integrated into an implantation simulation framework designed to provide a predictive tool for quantifying corneal remodeling and predict surgical outcomes of a novel dome-shaped nitinol intracorneal device, The GROSSO® Reshaper, developed to provide predictable corneal reshaping in patients with keratoconus. Device safety was previously assessed in rabbits. Clinical safety and efficacy are currently under evaluation in keratoconic patients.
Setting
PoliToBIOMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Torino, Italy.
Universidad de Zaragoza, Zaragoza, Spain.
Instituto de Microcirugía Ocular (IMO), Miranza Group, Barcelona, Spain.
Recornea srl, Trieste, Italy.
Methods
A patient-specific 3D keratoconic cornea was reconstructed by fitting experimental point cloud data acquired with a Pentacam, using a combination of Zernike polynomials for the optical zone and a quadratic surface for the peripheral region of the cornea. Corneal tissue was described using a fiber-reinforced hyperelastic Holzapfel–Gasser–Ogden (HGO) formulation with material parameters identified from air-puff–derived stress–strain curves. A zero-pressure algorithm was implemented to estimate the stress-free configuration before repressurization to physiological loading. Sagittal curvature maps and keratometric parameters were generated to validate reconstruction accuracy based on in vivo data.
Results
Keratometric parameters calculated from the reconstructed digital cornea showed strong agreement with experimental Pentacam data. Experimental keratometric values indicated Kflat = 55 D and Ksteep = 56 D, whereas the reconstructed digital model predicted Kflat = 56 D and Ksteep = 57 D. These values correspond to relative deviations of 1.8% for Kflat and 1.7% for Ksteep. Sagittal curvature maps derived from the reconstructed model qualitatively reproduced the experimental ectatic pattern, demonstrating similar cone location and steepening distribution. These findings confirm the geometric accuracy of the patient-specific reconstruction framework.
Conclusions
The reliability of the corneal reconstruction approach and the consistency of the adopted constitutive formulation were confirmed. A robust patient-specific framework was therefore established for reconstructing digital keratoconic corneas from in vivo data, explicitly incorporating the stress-free configuration and the anisotropic contribution of collagen fiber orientation. This validated computational method is currently integrated into an implantation simulation framework, previously validated in rabbit corneal models, aimed at providing a predictive tool for quantifying corneal remodeling and forecast surgical outcomes.