International Journal of Keratoconus and Ectatic Corneal Diseases

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VOLUME 10 , ISSUE 1--2 ( January-December, 2023 ) > List of Articles

Original Article

Two-year Outcomes of Transepithelial Customized Cross-linking for Mild to Moderate Keratoconus

Miltos Balidis, Spyridon Koronis, Penelope Burle de Politis, Georgios Sidiropoulos, Achilleas Rasoglou

Keywords : Corneal collagen cross-linking, Keratoconus, Transepithelial cross-linking

Citation Information : Balidis M, Koronis S, de Politis PB, Sidiropoulos G, Rasoglou A. Two-year Outcomes of Transepithelial Customized Cross-linking for Mild to Moderate Keratoconus. Int J Kerat Ect Cor Dis 2023; 10 (1--2):26-31.

DOI: 10.5005/jp-journals-10025-1196

License: CC BY-NC 4.0

Published Online: 23-04-2024

Copyright Statement:  Copyright © 2023; The Author(s).


Background/Aim: Corneal cross-linking remains the only treatment option capable of halting keratoconus progression. Customized cross-linking is a new topographically-guided protocol consisting of irradiating different corneal treatment zones with variable energy beam profiles. In this study cohort, customized cross-linking was combined with sustained oxygen delivery and high-energy pulsed UV-A irradiation at the apex of the cone, without epithelial debridement. This paper presents outcomes through 24 months postoperatively in keratoconus patients treated with this tailored cross-linking procedure. Materials and methods: This study involves 54 eyes of 43 patients with keratoconus. Visual acuity and corneal topography were recorded preoperatively. Every patient was examined at 1, 6, 12, and 24 months postoperatively and corneal topography and anterior optical coherence tomography were performed. Corrected distance visual acuity (CDVA), Kmax values, anterior and posterior elevation, and demarcation line depth were recorded. Results: Median CDVA improved from 0.14 to 0.01 logMAR (p < 0.001) at the 24-month visit. Kmax was successfully reduced from 53.2 ± 8.2 D to 51.5 ± 9.0 D (p < 0.001). Median anterior elevation decreased from 16 to 15 μm (p = 0.01), while median posterior elevation remained stable at 40 μm (p = 0.35), at 12 months. In the first postoperative month, the mean demarcation line depth was 344.6 ± 62.8 μm, equating to 72.7 ± 10.9% of corneal thickness. Conclusion: Customized corneal cross-linking is a safe and effective procedure for the management of keratoconus, customized and less invasive than cross-linking with epithelial removal. Our encouraging results and minimal complication rates point to a very promising technique that may change the standards for cross-linking. What is already known on this topic • Transepithelial cross-linking previously has been found to have lower effectiveness than standard cross-linking with epithelial debridement. • Customized high-energy pulsed UV-A delivery profiles and oxygen supplementation, as in the present procedure, may enhance the effectiveness of transepithelial cross-linking. What this study adds • At 2 years of follow-up, customized transepithelial oxygen-supplemented cross-linking appears to be an effective procedure for keratoconus, with results generally comparable to the Dresden protocol. • This high-energy procedure was well-tolerated, with minimal adverse events. How this study might affect research, practice, or policy • This study may contribute to the establishment of customized corneal cross-linking as a gold-standard treatment for the stabilization of keratoconus.

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