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Published on: December 22, 2015
Assessing UVA and Laser-Induced Crosslinking via Brillouin Microscopy
Christian A Iriarte-Valdez1,2, Johannes Wenzel1,2, Emilie Baron1,2
1Institute of Quantum Optics, Leibniz University Hannover, Hannover, Germany.
Abstract:
Keratoconus and other corneal ectatic disorders involve the degradation of collagen fibers, which compromises the corneal biomechanical properties. Ultraviolet-A (UVA) crosslinking has emerged as the primary treatment to slow down collagen degradation. This treatment is limited in both penetration depth and spatial precision, potentially leading to unwanted side effects. This study compares the changes in biomechanical properties of corneas crosslinked with UVA irradiation and a near-infrared femtosecond laser, using Brillouin microscopy. The biomechanical properties of the crosslinked regions were mapped in terms of Brillouin frequency shift in three dimensions. UVA crosslinking showed an average increase in Brillouin frequency shift of ~100 MHz. We demonstrate targeted spatial and axial corneal femtosecond crosslinking, with similar Brillouin frequency shift values to UVA in crosslinked regions.
Insights
Corneal crosslinking using a femtosecond laser offers targeted treatment for ectatic disorders, matching Ultraviolet-A (UVA) crosslinking
Area of Science:
- Ophthalmology
- Biomedical Engineering
- Materials Science
Background:
- Corneal ectatic disorders degrade collagen, impairing biomechanical integrity.
- Ultraviolet-A (UVA) crosslinking is the standard treatment but has limitations in depth and precision.
- Unwanted side effects can occur due to imprecise UVA crosslinking.
Purpose of the Study:
- To compare the biomechanical changes induced by UVA and near-infrared femtosecond laser corneal crosslinking.
- To evaluate the precision and effectiveness of femtosecond laser crosslinking for corneal ectatic disorders.
Main Methods:
- Brillouin microscopy was used to map 3D biomechanical properties (Brillouin frequency shift).
- Corneal samples were crosslinked using both UVA irradiation and a near-infrared femtosecond laser.
- Changes in biomechanical properties were quantified in the crosslinked regions.
Main Results:
- UVA crosslinking resulted in an average Brillouin frequency shift increase of approximately 100 MHz.
- Femtosecond laser crosslinking demonstrated targeted spatial and axial precision.
- The biomechanical changes (Brillouin frequency shift) from femtosecond laser crosslinking were comparable to UVA crosslinking.
Conclusions:
- Near-infrared femtosecond laser crosslinking provides a precise alternative to UVA treatment for corneal ectatic disorders.
- This laser-based method achieves similar biomechanical enhancement to UVA crosslinking with improved spatial control.
- Femtosecond laser crosslinking shows potential for safer and more effective treatment of conditions like keratoconus.
