A steep peripheral ring in irregular cornea topography, real or an instrument error?

Purpose To demonstrate that the steep peripheral ring (red zone) on corneal topography after myopic laser in situ keratomileusis (LASIK) could possibly due to instrument error and not always to a real increase in corneal curvature. Methods A spherical model for the corneal surface and modifying topo...

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Detalles Bibliográficos
Autores: Galindo-Ferreiro, Alicia, Galvez-Ruiz, Alberto, Schellini, Silvana A. [UNESP], Galindo-Alonso, Julio
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2016
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:inglés
OAI Identifier:oai:repositorio.unesp.br:11449/173711
Acceso en línea:http://dx.doi.org/10.1016/j.sjopt.2016.04.002
http://hdl.handle.net/11449/173711
Access Level:acceso abierto
Palabra clave:Irregular corneal astigmatism
Red zone
Spherical aberration
Topography
Descripción
Sumario:Purpose To demonstrate that the steep peripheral ring (red zone) on corneal topography after myopic laser in situ keratomileusis (LASIK) could possibly due to instrument error and not always to a real increase in corneal curvature. Methods A spherical model for the corneal surface and modifying topography software was used to analyze the cause of an error due to instrument design. This study involved modification of the software of a commercially available topographer. Results A small modification of the topography image results in a red zone on the corneal topography color map. Conclusion Corneal modeling indicates that the red zone could be an artifact due to an instrument-induced error. The steep curvature changes after LASIK, signified by the red zone, could be also an error due to the plotting algorithms of the corneal topographer, besides a steep curvature change.