Elsevier

Ophthalmology

Volume 120, Issue 5, May 2013, Pages 908-916
Ophthalmology

Original article
Corneal Cross-Linking as a Treatment for Keratoconus: Four-Year Morphologic and Clinical Outcomes with Respect to Patient Age

Presentated at: American Academy of Ophthalmology Annual Meeting, October 2011, Orlando, Florida.
https://doi.org/10.1016/j.ophtha.2012.10.023Get rights and content

Purpose

To report the 4-year outcomes of corneal cross-linking (CXL) for progressive keratoconus in a population of different age groups.

Design

Retrospective, single-center, nonrandomized clinical study.

Participants

Four hundred consecutive eyes treated with corneal CXL for progressive keratoconus from April 2006 through April 2010.

Intervention

After removal of the epithelium, the cornea was irrigated for 30 minutes with a solution of 0.1% riboflavin and 20% dextran, followed by irradiation with an ultraviolet A light of 3 mW/cm2 for 30 minutes.

Main Outcome Measures

Best-corrected visual acuity (BCVA), sphere and cylinder refraction, corneal topography, Scheimpflug tomography, and aberrometry were assessed at baseline and at 1, 6, 12, 24, 36, and 48 months after corneal CXL treatment. The compiled data were stratified according to age (group A, younger than 18 years; group B, 18–29 years; group C, 30–39 years; and group D, older than 40 years).

Results

Comparative analysis included 400 eyes of 301 patients. Functional results showed a significant increase in BCVA in group A by a mean reduction of –0.11 logarithm of the minimum angle of resolution (logMAR) after 12 months, in group B by a mean reduction of –0.31 logMAR after 36 months, in group C by a mean reduction of –0.33 logMAR after 36 months, and in group D by a mean reduction of –0.26 logMAR after 36 months. Morphologic results showed an analogous regularization of corneal shape with a significant reduction of opposite sector index by a mean value of –0.53 at 12 months in group A, –1.14 at 36 months in group B, –1.10 at 36 months in group C, and –0.55 at 12 months for group D. Optical quality improvement was demonstrated by a mean significant reduction of coma –1.52 μm after 12 months in group A, –1.58 μm after 24 months in group B, –2.57 μm after 36 months for group C, and –0.25 μm after 36 months in group D.

Conclusions

Outcomes stratified by age indicate the efficacy of corneal CXL in stabilizing the progression of ectatic disease in all age groups and improving the functional and morphologic parameters in select groups. Results indicated better functional and morphologic results in the population between 18 and 39 years of age.

Financial Disclosure(s)

Proprietary or commercial disclosure may be found after the references.

Section snippets

Study Design

This was a retrospective, single-center, nonrandomized clinical study.

Population

This retrospective study included all eyes that underwent corneal CXL from April 2006 through April 2010 at the Department of Ophthalmology, Istituto Clinico Humanitas, Rozzano, Milan, Italy. The inclusion criteria for the treatment of corneal CXL were documentation of the progression of keratoconus, patients older than 9 years, signed informed consent, and corneal pachymetry results of more than 400 μm.

The preoperative

Results

Four hundred eyes of 301 patients were evaluated. The comparative functional analysis comprised the following: 49 eyes of patients between 9 and 17 years of age (12.25%), 185 eyes of patients between 18 and 29 years of age (46.25%), 115 eyes of patients between 30 and 39 years of age (28.75%), and 51 eyes of patients older than 40 years of age (12.75%). The mean age of patients was 29±10 years, and the sex distribution was 27.25% female (109 eyes). The postoperative follow-up period was

Discussion

Corneal collagen CXL modifies the natural history of progressive keratoconus by stabilizing the corneal tissue, preventing and slowing the progression of the ectatic disease.11, 12, 13, 14 The outcome of this procedure was stratified in this retrospective study according to age. Because keratoconus in children is more aggressive,9 pediatric patients were evaluated more frequently than adults. The availability of an extended 48-month follow-up allowed for extensive data collection aimed at

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    Manuscript no. 2012-143.

    Financial Disclosure(s): The author(s) have made the following disclosure(s):

    Paolo Vinciguerra - Consultant - Nidek and Oculus.

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