Comparative Analysis of Some Modal Reconstruction Methods of the Shape of the Cornea from Corneal Elevation Data

Abstract

The Zernike (and especially, the Bhatia-Wolf) polynomials constitute a reliable reconstruction method of a nonseverely aberrated surface with a small surface regularity index (SRI). However, they fail to capture small deformations of the anterior surface of a synthetic cornea. The most promising approach is a combined one that balances the robustness of the Zernike fit with the localization of the RBF.

Characterization of corneal structure in keratoconus

“…7,8,[59][60][61][62][63] The digital analysis of the image of the Placido disks projected on the cornea has also been shown to be a valid tool for keratoconus diagnosis, avoiding the use of estimated data or parameters obtained indirectly. 64 Specifically, the use of primary corneal indices characterizing the asymmetry of the mires seems to be especially useful for keratoconus detection.…”

Weighted Zernike polynomial fitting in steep corneas sampled in Cartesian grid

“…Thus, it is of easy implementation in existing 335 systems and the obtained results permit a classical interpretation of the Zernike coefficients in terms of optical aberrations. The significance of the Zernike coefficients of the modal approach is conserved, allowing a direct relation with optical aberrations 340 and thus having this advantage over other reported methods [17][18][19].…”

Computational aspects of the through-focus characteristics of the human eye

“…It involves approximation by Gaussian radial basis functions (GRBF), which are a standard tool in the solution of a variety of practical purposes, ranging from engineering to numerical analysis of partial derivative equations. Recently, they also found application in the context of ophthalmic optics [26]. A more general version of this type of functions (using the socalled anisotropic radial basis functions) was developed for fitting corneal elevation data [27,28].…”