We have located links that may give you full text access.
Anterior and posterior corneal changes after crosslinking for keratoconus.
Optometry and Vision Science : Official Publication of the American Academy of Optometry 2014 Februrary
PURPOSE: To evaluate anterior and posterior changes in corneal topography and tomography after corneal crosslinking (CXL) in eyes with progressive keratoconus.
METHODS: Scheimpflug analyses (Pentacam, Oculus) of 20 eyes with keratoconus performed before and after corneal CXL were included into retrospective analysis. Mean follow-up was 2 years. Changes in topographic, tomographic, and pachymetric values were statistically analyzed applying analysis of variance. Further, the distance and direction between the anterior maximum keratometry (K(max)) and the apex as well as the distance and direction between the thinnest point in corneal thickness (TPCT) and the corneal apex before and after CXL were studied.
RESULTS: Two years after CXL, a statistically significant reduction of the keratometry at the flat meridian (-0.8 D, p < 0.05), the steep meridian (-0.5 D, p < 0.05), the "index of surface variance" (-5.3, p < 0.05), and the "index of highest decentration" (-0.05, p < 0.05) could be demonstrated. While the elevation of the front surface at the apex decreased (-1.5 μm, p < 0.05), the back elevation at the apex (+2 μm, p < 0.05) increased. Although not reaching statistical significance, the maximum front and back elevation demonstrated the same trend; while maximum front elevation data remained stable (-0.3 μm, p = 0.961), maximum back elevation data increased (+6.7 μm, p = 0.122). The corneal thickness at the apex (-22.0 μm, p < 0.001) and the TPCT (-20.0 μm, p < 0.001) decreased, leading to an increase of the corneal thickness progression from the corneal apex to the periphery. The position of K(max) and TPCT remained stable.
CONCLUSIONS: Corneal topography proved to be useful in the follow-up for CXL because of significant changes in the keratometry. Increasing posterior elevation values, despite a stabilized anterior corneal surface, might be a sign of ongoing ectatic changes in the posterior corneal surface.
METHODS: Scheimpflug analyses (Pentacam, Oculus) of 20 eyes with keratoconus performed before and after corneal CXL were included into retrospective analysis. Mean follow-up was 2 years. Changes in topographic, tomographic, and pachymetric values were statistically analyzed applying analysis of variance. Further, the distance and direction between the anterior maximum keratometry (K(max)) and the apex as well as the distance and direction between the thinnest point in corneal thickness (TPCT) and the corneal apex before and after CXL were studied.
RESULTS: Two years after CXL, a statistically significant reduction of the keratometry at the flat meridian (-0.8 D, p < 0.05), the steep meridian (-0.5 D, p < 0.05), the "index of surface variance" (-5.3, p < 0.05), and the "index of highest decentration" (-0.05, p < 0.05) could be demonstrated. While the elevation of the front surface at the apex decreased (-1.5 μm, p < 0.05), the back elevation at the apex (+2 μm, p < 0.05) increased. Although not reaching statistical significance, the maximum front and back elevation demonstrated the same trend; while maximum front elevation data remained stable (-0.3 μm, p = 0.961), maximum back elevation data increased (+6.7 μm, p = 0.122). The corneal thickness at the apex (-22.0 μm, p < 0.001) and the TPCT (-20.0 μm, p < 0.001) decreased, leading to an increase of the corneal thickness progression from the corneal apex to the periphery. The position of K(max) and TPCT remained stable.
CONCLUSIONS: Corneal topography proved to be useful in the follow-up for CXL because of significant changes in the keratometry. Increasing posterior elevation values, despite a stabilized anterior corneal surface, might be a sign of ongoing ectatic changes in the posterior corneal surface.
Full text links
Related Resources
Trending Papers
Heart failure with preserved ejection fraction: diagnosis, risk assessment, and treatment.Clinical Research in Cardiology : Official Journal of the German Cardiac Society 2024 April 12
Proximal versus distal diuretics in congestive heart failure.Nephrology, Dialysis, Transplantation 2024 Februrary 30
Efficacy and safety of pharmacotherapy in chronic insomnia: A review of clinical guidelines and case reports.Mental Health Clinician 2023 October
World Health Organization and International Consensus Classification of eosinophilic disorders: 2024 update on diagnosis, risk stratification, and management.American Journal of Hematology 2024 March 30
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app