Related Experiment Video
Updated: Feb 15, 2026

Author Spotlight: Advancing Therapeutics with Biocompatible Sodium Alginate Hydrogel Microspheres
Published on: June 7, 2024
Corneal cross-linking in keratoconus using the standard and rapid treatment protocol: differences in demarcation line
Sara Brittingham1, Christoph Tappeiner1, Beatrice E Frueh1
1Department of Ophthalmology, Inselspital, University of Bern, Bern, Switzerland.
Purpose:
To compare the occurrence rate and depth of the demarcation line and topographical outcome after corneal cross-linking (CXL) for keratoconus using two different treatment protocols.
Methods:
A retrospective analysis of 131 eyes with progressive keratoconus treated with CXL using riboflavin and UV-A was performed. Eyes were treated either with the standard Dresden protocol (30 minutes irradiation, 3 mW/cm(2), UV-XTM 1000) or a rapid protocol (10 minutes irradiation, 9 mW/cm(2), UV-XTM 2000). The presence and depth of the corneal demarcation line was assessed with an anterior segment optical coherence tomography device 1 month after CXL by a masked observer. Corneal topography and tomography was performed at baseline and at 12-month follow-up with Pentacam and the TMS (Topographic Modeling System) device.
Results:
In the standard protocol group, 76.5% (62/81) of treated corneas revealed a demarcation line 1 month after CXL, whereas such a demarcation line was observed in only 22% (11/50) of eyes treated with the rapid protocol (P < 0.0001). The demarcation line was significantly more superficial in the rapid protocol group (P = 0.004). Corneal topography values between baseline and 12 months after CXL showed a mean change of -0.76 diopters (D) in Kmax (SD ± 2.7) in the standard protocol group versus a mean change of +0.72 D in Kmax (SD ± 1.5) in the rapid protocol (P = 0.007).
Conclusions:
The rapid CXL protocol negatively influences the occurrence and depth of the demarcation line 1 month after CXL. Our results show a negative effect on the topographical outcome 1 year after CXL.
More Related Videos
10:21Protocol for HER2 FISH Using a Non-cross-linking, Formalin-free Tissue Fixative to Combine Advantages of Cryo-preservation and Formalin Fixation
Published on: December 25, 2017
07:29Three Different Protocols of Corneal Collagen Crosslinking in Keratoconus: Conventional, Accelerated and Iontophoresis
Published on: November 12, 2015
Related Concept Videos
Crossing Over
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process...
Cross-Sectional Research
Covalently Linked Protein Regulators
These groups modify specific amino acids in a protein....
Monohybrid Crosses
Predicting Reaction Outcomes
Standard Enthalpy of Formation