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. 2015 Jul-Sep;8(3):180-6.
doi: 10.1016/j.optom.2014.05.006. Epub 2014 Jun 16.

Long-term results of corneal collagen crosslinking for progressive keratoconus

Maddalena De Bernardo  1 , Luigi Capasso  2 , Michele Lanza  3 , Antonia Tortori  2 , Stefania Iaccarino  1 , Michela Cennamo  1 , Maria Borrelli  3 , Nicola Rosa  4
Affiliations

Long-term results of corneal collagen crosslinking for progressive keratoconus

Maddalena De Bernardo et al. J Optom. 2015 Jul-Sep.

Abstract
in English, Spanish

Purpose: To evaluate long-term keratoconus stability after corneal crosslinking (CXL) with riboflavin.

Methods: In this prospective study, 57 eyes of 55 patients with progressive keratoconus, consecutively treated with ultraviolet A (UVA) - riboflavin CXL, were examined with the corneal topographer Pentacam, the biometer IOLMaster and the analyzer of corneal biomechanics Ocular Response Analyzer before and during a 24 months follow-up after CXL.

Results: Twenty-four months after CXL, there was a significant improvement in best corrected visual acuity (BCVA) (P<0.01), a significant decrease in corneal thinnest point (CTP), keratometry readings at the keratoconus apex (K max), and corneal volume (CV) (P<0.01), and a significant increase in axial eye length (AL) (P=0.01). No significant changes in anterior chamber volume (ACV) and depth (ACD), (P=0.8), corneal hysteresis (CH) (P=0.16) and corneal resistance factor (CRF) (P=0.06) were found. However, in the subgroup of patients with decreased K max readings 24 months after treatment, both CH and CRF showed a significant reduction (P<0.01).

Conclusion: In the first month after the procedure, CXL induces a reduction in corneal volume. During the 24 months follow-up the cornea tends to recover its original volume with a persistence of the CXL efficacy.

Objetivo: Evaluar la estabilidad del queratocono a largo plazo tras cross-linking corneal (CXL) con riboflavina.

Métodos: En este estudio prospectivo, se examinaron 57 ojos de 55 pacientes con queratocono progresivo, tratados consecutivamente con UVA-CXL con riboflavina utilizando el topógrafo corneal Pentacam, el biómetro IOLMaster y el analizar de la biomecánica corneal “Ocular Response Analyzer” preoperatoriamente y a los 24 meses de haberse realizado el CXL.

Resultados: A los veinticuatro meses del CXL, se produjo una mejora considerable de la agudeza visual mejor corregida (BCVA) (p < 0.01), un importante decremento del punto más fino de la córnea (CTP), de las medidas queratométricas en el vértice del queratocono (K max), y del volumen de la córnea (VC) (p < 0.01), y un incremento significativo de la longitud axial del ojo (LA) (p = 0.01). No se produjeron cambios significativos en el volumen de la cámara anterior (VCA) ni en la profundidad de la misma (PCA), (p = 0.8), histéresis de la córnea (HC) (p = 0.16) y factor de resistencia de la córnea (FRC) (p = 0.06). Sin embargo, en el subgrupo de pacientes con disminución de los valores de K max, a los 24 meses del tratamiento, tanto la HC como la FRC mostraron una reducción considerable (p < 0.01).

Conclusión: Durante el primer mes tras la intervención, el CXL induce una reducción del volumen de la córnea. Durante los 24 meses de seguimiento, la córnea tiende a recuperar su volumen original, persistiendo la eficacia del CXL.

Keywords: Axial eye length; Corneal crosslinking; Corneal thinnest point; Cross-linking corneal; Grosor corneal más delagado; Keratoconus; Keratometry readings; Longitud axial del ojo; Mediciones del queratómetro; Queratocono.

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Figures

Figure 1
Figure 1
Percentage of eyes with stability, increase or decrease in corneal thinnest point (CTP) values.
Figure 2
Figure 2
Percentage of eyes with stability, increase or decrease in keratometry at keratoconus apex (K max) values.
Figure 3
Figure 3
Percentage of eyes with stability, increase or decrease in axial eye length (AL) values.
See this image and copyright information in PMC

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