Corneal thickness and elevation maps computed from optical rotary scans.

Sandra Franco; José B Almeida; Manuel Parafita

doi:10.3928/1081-597x-20040901-31

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Corneal thickness and elevation maps computed from optical rotary scans.

Sandra Franco·José B Almeida·Manuel Parafita

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Abstract

PURPOSE: Recently, the authors presented a technique that allows corneal thickness measurements along any meridian from optical sections obtained using a rotary scanning system. This paper presents three-dimensional mapping of the corneal thickness and topography of both corneal surfaces, obtained with the rotary system. METHOD: Corneal thickness and topography are computed from optical sections obtained by illumination with a collimated beam expanded in a fan by a small cylindrical lens. This lens is provided with motor driven rotation to perform automated rotary scanning of the whole cornea. Two cameras are used to capture the images of the optical sections. RESULTS: With this system, it is possible to obtain measurements of corneal thickness, as well as corneal topography. Corneal thickness and elevation maps are shown. CONCLUSIONS: Although still under development, this new optical system allows measurement of the thickness of the whole cornea as well as topographical mapping of both corneal surfaces.

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Sandra Franco, José B Almeida, Manuel Parafita. Corneal thickness and elevation maps computed from optical rotary scans.. https://doi.org/10.3928/1081-597x-20040901-31

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