# Non-Linear Optical femtosecond laser device to alter corneal curvature and stiffness.

> **NIH NIH R43** · M2-COR, INC. · 2022 · $255,671

## Abstract

We have recently shown that photo-activation of riboflavin and mechanical stiffening of the
cornea can be achieved using 760 nm infrared Femtosecond laser light through a two photon,
nonlinear optical (NLO) process. The primary advantage of NLO over the existing
technology is that cross linking occurs only within the two-photon focal volume of the FS
laser light, providing precise control over the area, depth and geometry of the
mechanically stiffened cornea that can be easily tailored to the patient's corneal
topography. We have further patented an FS laser delivery system and shown that can vary
the two-photon focal volume by changing the numerical aperture (NA) of the focusing lens to
greatly expand the lateral and axial dimensions of the CXL region up to 150 μm of the corneal
thickness. This greatly speeds up the NLO process, providing a more rapid procedure
compared to that of standard treatments. We have also established that using regeneratively
amplified FS laser pulses, mechanical stiffening of rabbit corneas can be achieved with an
overall power of <46.1 mW, below the ANSI thermal limits for laser exposure to the eye.
Additionally, we have shown in a live rabbit model that our NLO CXL device can crosslink a 4
mm diameter central corneal region in 5 minutes and produce 1-2 diopters of corneal flattening.
We have further developed an FS corneal epithelial micromachining method to enhance
penetration of chemicals through the epithelium without producing epithelial damage before or
after the procedure, thus avoiding the major adverse effects of standard protocols. With this
novel technology now in hand, we are ready to develop a clinical prototype that will allow for the
testing of this device to treat keratoconus and low degrees of myopia, hyperopia, presbyopia
and astigmatism.

## Key facts

- **NIH application ID:** 10392214
- **Project number:** 1R43EY032815-01A1
- **Recipient organization:** M2-COR, INC.
- **Principal Investigator:** Michael Karavitis
- **Activity code:** R43 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $255,671
- **Award type:** 1
- **Project period:** 2022-03-01 → 2024-02-29

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10392214

## Citation

> US National Institutes of Health, RePORTER application 10392214, Non-Linear Optical femtosecond laser device to alter corneal curvature and stiffness. (1R43EY032815-01A1). Retrieved via AI Analytics 2026-05-27 from https://api.ai-analytics.org/grant/nih/10392214. Licensed CC0.

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