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Evaluación de un nomograma basado en la aberración cómica para la implantación simétrica del segmento de anillo

Nicole Mechleb¹, Christophe Panthier¹, Fillipo Fabro²

¹Department of Ophthalmology, Rothschild Foundation, Paris, France.

Canadian journal of ophthalmology. Journal canadien d'ophtalmologie

|February 12, 2026

Resumen

Este estudio muestra que el uso de segmentos de anillos corneales intrastromales guiados por mediciones de aberración cómica mejora la visión y reduce las irregularidades corneales en pacientes con queratocono. La orientación hacia el coma vertical mejora la calidad visual y reduce las aberraciones de orden superior.

Área de la Ciencia:

Oftalmología Oftalmología.
Cirugía de la córnea Cirugía de la córnea
Corrección de errores refractivos por refracción.

Sus antecedentes:

El queratocono es un adelgazamiento progresivo de la córnea, que conduce a astigmatismo irregular y agudeza visual reducida.
Los segmentos de anillo corneal intrastromal (ICRS) se utilizan para regular la forma de la córnea y mejorar la visión en el queratocono.
Los nomogramas actuales para la implantación del ICRS no siempre tienen en cuenta las aberraciones corneales específicas como el coma.

Objetivo del estudio:

Para evaluar los resultados a corto plazo de la implantación del ICRS utilizando un nomograma basado en la aberración cómica.
Evaluar la efectividad de este enfoque en varios patrones y etapas de queratocono.
Para analizar el impacto en la agudeza visual, el error de refracción, la topografía de la córnea y las aberraciones.

Principales métodos:

Un estudio retrospectivo de un solo centro incluyó 91 ojos de 68 pacientes que se sometieron a implantación de ICRS.
Las evaluaciones preoperatorias incluyeron agudeza visual (UDVA, CDVA), examen de lámpara de hendidura y topografía corneal Pentacam HR.
Los datos analizados incluyeron cambios en la agudeza visual, cilindro, equivalente esférico, queratometría y aberraciones (RMS, HOA, coma) a los 3 meses después de la cirugía.

Principales resultados:

Se observaron mejoras significativas en UDVA y CDVA después de la implantación.
Se observó una reducción significativa en el cilindro (2.13 D) y el equivalente esférico (2.12 D).
La topografía corneal mostró el aplanamiento de los meridianos y una disminución en Kmax. La EMR total, la EMR HOA y las aberraciones cómicas disminuyeron significativamente.

Conclusiones:

Dirigirse al coma vertical con la implantación de ICRS mejora los resultados topográficos y refractivos en el queratocono.
Este enfoque reduce efectivamente el RMS total y las aberraciones de orden superior, mejorando la calidad visual general.
Un nomograma basado en la aberración cómica ofrece una estrategia prometedora para la implantación del ICRS en el manejo del queratocono.

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