Corneal Topographic Restoration Imaging Based on Placido Disc

Abstract

Corneal topography serves as an essential reference for diagnostic treatment in ophthalmology.Accurate corneal topography is crucial for clinical practice.In this study, the refractive power calculation was performed based on the initial corneal information collected using the Placido disc.A corneal point cloud model was established in polar coordinates, and an interpolation algorithm was proposed to fill missing points of the local bicubic B-spline by searching control points in the self-defined interpolation matrix.The grid interpolation of the point cloud information and the smooth imaging of the final topographic map were achieved by Delaunay triangulation and Gaussian kernel function smoothing.Experiment results show that the proposed interpolation algorithm has higher accuracy than previous algorithms.The mean absolute error between the measured diopter of the original detection and the reconstructed is less than 0.300 D, indicating that this algorithm is feasible.

Keywords

corneal topography / Placido disc / point cloud model / bicubic B-spline / Gaussian kernel function

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Funding

Shanghai Science and Technology Program, China(20DZ2251400)