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  • AAO OTAC Cornea and Anterior Segment Disorders Panel, Hoskins Center for Quality Eye Care


    A Report by the American Academy of Ophthalmology Ophthalmic Technology Assessment Committee Cornea and Anterior Segment Disorders Panel

    Maria S. Cortina, MD,1 Mark A. Greiner, MD,2 Anthony N. Kuo, MD,3 Jennifer Y. Li, MD,4 Darby D. Miller, MD, MPH,5 Roni M. Shtein, MD, MS,6 Peter B. Veldman, MD,7 Jia Yin, MD, PhD, MPH,8 Stephen J. Kim, MD,9 Joanne F. Shen, MD10

    Ophthalmology, In Press © 2024 by the American Academy of Ophthalmology. Click here for free access to the OTA.

    Purpose: To review the evidence on the safety and effectiveness of epithelium-off corneal collagen cross-linking (CXL) for the treatment of progressive corneal ectasia.

    Methods: A literature search of the PubMed database was most recently conducted in March 2024 with no date restrictions and limited to studies published in English. The search identified 359 citations that were reviewed in abstract form, and 43 of these were reviewed in full text. High-quality randomized clinical trials comparing epithelium-off CXL with conservative treatment in patients who have keratoconus (KCN) and post-refractive surgery ectasia were included. The panel deemed 6 articles to be of sufficient relevance for inclusion and these were assessed for quality by the panel methodologist; 5 were rated level I and 1 was rated level II. There were no level III studies.

    Results: This analysis includes 6 prospective, randomized controlled trials that evaluated the use of epithelium-off CXL to treat progressive KCN (5 studies) and post-laser refractive surgery ectasia (1 study), with a mean postoperative follow-up of 2.4 years (range, 1–5 years). All studies showed a decreased progression rate in treated patients compared with controls. Improvement in the maximum keratometry (Kmax) value, corrected distance visual acuity (CDVA), and uncorrected distance visual acuity (UDVA) was observed in the treatment groups compared with control groups. A decrease in corneal thickness was observed in both groups but was greater in the CXL group. Complications were rare.

    Conclusions: Epithelium-off CXL is effective in reducing the progression of KCN and post-laser refractive surgery ectasia in most treated patients with an acceptable safety profile. 

    1Professor of Ophthalmology, Department of Ophthalmology and Visual Science, University of Illinois College of Medicine, Chicago, Illinois
    2Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
    3Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina
    4UC Davis Eye Center, University of California, Davis, California
    5Department of Ophthalmology, Mayo Clinic, Jacksonville, Florida
    6Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan
    7Department of Ophthalmology & Visual Science, The University of Chicago, Chicago, Illinois
    8Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
    9Department of Ophthalmology, Vanderbilt University School of Medicine, Nashville, Tennessee
    10Department of Ophthalmology, Mayo Clinic, Scottsdale, Arizona