The prevalence of myopia has increased worldwide over the last 50 years. Its incidence in the United States and Europe is now almost twice that 50 years ago, and it is even more prevalent in East Asia. Spectacles and contact lenses remain the most common means of vision correction, but the permanent correction of refractive errors, by refractive surgery, has emerged as an attractive alternative. However, such surgery is an invasive procedure that may compromise corneal structure, and post-surgical complications have been reported. We propose a novel, non-invasive approach to permanent vision correction based on a different mode of laser–cornea interaction. Our approach induces the formation of a low-density plasma that produces reactive oxygen species, which react with the surrounding proteins, forming crosslinks and triggering spatially resolved changes in mechanical properties. We show that the proposed method changes the refractive power of the eye, and confirm its safety and stability.
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This research was partly funded by the Wallace H. Coulter Foundation. The authors thank S. Trokel for helpful discussions and comments on the manuscript, D. Paik for allowing us to use the equipment in his laboratory, J. Yu, F. Ji, C. Diao and J. Fan for assisting with laser treatment, the experimental set-up and figure preparation, D. Bian for performing the refractive index measurements, and W.D.A.M. De Boer and W. Yang for running TPF experiments. The authors also thank S. Jockusch for help with running EPR spectroscopy experiments. The authors acknowledge Fundação para a Ciência e Tecnologia (FCT) projects PTDC/SAU-ENB/122128/2010 and PEST-C/SAU/UI3282/2013 and COMPETE programmes FCOMP-01-0124-FEDER-021163 and FCOMP-01-0124-FEDER-037299 for support for the multiphoton microscopy equipment. The authors thank JenLab GmbH for providing the required equipment and A. Kaiser for transporting the pig eyes.
The authors declare no competing interests.
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Wang, C., Fomovsky, M., Miao, G. et al. Femtosecond laser crosslinking of the cornea for non-invasive vision correction. Nature Photon 12, 416–422 (2018). https://doi.org/10.1038/s41566-018-0174-8
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