Document Type
Article
Publication Date
10-2017
Abstract
Purpose
To characterize corneal wound healing in a rabbit model after flapless refractive lenticule extraction with a 345 nm ultraviolet femtosecond laser.
Setting
Departments of Ophthalmology and Anatomy II, University of Erlangen-Nürnberg and Wavelight GmbH, Erlangen, Germany.
Design
Methods
Flapless refractive lenticule extraction was performed in 1 eye each of 20 New Zealand white rabbits (−5.0 diopters). Groups of 4 animals were euthanized after 48 hours, 1 week, 2 weeks, 4 weeks, and 3 months, respectively. Corneal samples were prepared for histology and fluorescence microscopy. To assess corneal cell death, proliferation, and myofibroblastic transdifferentiation, terminal uridine deoxynucleotidyl nick end-labeling (TUNEL) assay as well as immunostaining for Ki67 and α-smooth muscle actin (αSMA) were performed on sagittal cryosections.
Results
Histology revealed a zone of keratocyte depletion with a thickness of approximately 50 μm around the extraction site. At 48 hours, pronounced TUNEL staining of keratocytes was detected around the interface (159.9 cells/mm ± 18.4 [SD]), which steadily decreased to 74.9 ± 19.8 cells/mm at 1 week and 5.7 ± 4.8 cells/mm at 2 weeks. Ki67 staining of keratocytes was evident at 48 hours (10.0 ± 3.8 cells/mm), which then decreased at 1 week (5.2 ± 1.7 cells/mm) and 2 weeks (0.4 ± 0.5 cells/mm). From 4 weeks onward, no TUNEL or Ki67 staining was detected. The corneal stroma was αSMA-negative at all timepoints.
Conclusion
Application of the 345 nm laser showed no signs of problematic repair processes in the cornea, which supports the initiation of the clinical phase.
Recommended Citation
Hammer, C. M., Petsch, C., Klenke, J., Skerl, K., Wüllner, C., Donitzky, C., ... & Menzel-Severing, J. (2017). Wound healing in rabbit corneas after flapless refractive lenticule extraction with a 345 nm ultraviolet femtosecond laser. Journal of Cataract & Refractive Surgery, 43(10), 1335-1342. DOI: https://doi.org/10.1016/j.jcrs.2017.07.034
Included in
Animal Experimentation and Research Commons, Animal Studies Commons, Other Medical Sciences Commons
Comments
© 2017 The Authors. Published by Elsevier Inc. on behalf of ASCRS and ESCRS. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).