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Updated: Jul 25, 2026
07:29
Three Different Protocols of Corneal Collagen Crosslinking in Keratoconus: Conventional, Accelerated and Iontophoresis
Published on: November 12, 2015
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Assessment of Corneal Cross-Linking Effect on Progressive Keratoconus by Using the ABCD Grading System
Mazen Alzahrani1, Omer Alammari2, Abdulelah Binyamin3
1Department of Anterior Segment, Jeddah Eye Hospital, Jeddah, Saudi Arabia.
Clinical Ophthalmology (Auckland, N.Z.)
|August 27, 2024
Summary
Corneal cross-linking significantly altered ABCD parameters in progressive keratoconus patients. This study shows changes in corneal curvature and thickness, aiding in monitoring treatment success.
Area of Science:
- Ophthalmology
- Corneal Surgery
- Medical Imaging
Background:
- Keratoconus is a progressive eye condition causing thinning and bulging of the cornea.
- Corneal cross-linking (CXL) is a treatment to halt keratoconus progression.
- The ABCD system offers a comprehensive assessment of corneal parameters.
Purpose of the Study:
- To evaluate changes in corneal parameters using the ABCD system 6 months after corneal cross-linking in progressive keratoconus patients.
- To assess the efficacy of CXL in stabilizing corneal ectasia.
Main Methods:
- Retrospective study of 16 eyes of 16 keratoconus patients who underwent CXL.
- Corneal tomography and ABCD system parameters (A, B, C, D) were evaluated preoperatively and 6 months postoperatively.
- Maximal keratometry (Kmax), Belin/Ambrósio Enhanced Ectasia Display, and vertical asymmetry index were also monitored.
Main Results:
- Parameters A, B, and C showed significant changes (P=0.000) 6 months post-CXL.
- Parameter A increased, while parameters B and C decreased, indicating corneal stabilization.
- Significant differences were observed in Kmax, K1, and Belin/Ambrósio Enhanced Ectasia Display, but not in parameter D, K2, or average pachymetric progression index.
Conclusions:
- Corneal cross-linking can lead to significant changes in corneal parameters assessed by the ABCD system.
- Monitoring anterior and posterior corneal curvatures and thickness profiles is crucial for evaluating keratoconus progression and CXL success.
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