Second-harmonic microscopy of ex vivo porcine corneas

The ex vivo cornea of porcine eyes has been studied with second-harmonic microscopy with a laboratory-built system to examine the structure of collagen fibrils at different length scales, as well as the image dependence on polarization and wavelength of the illumination source. We found that collagen fibrils can effectively be visualized with second-harmonic microscopy, in agreement with previous findings, at different wavelengths of the illumination. The same laser source used for imaging may also be used to induce changes to the corneal tissues that are observable both in the linear and second-harmonic imaging channels. Such studies are essential first steps towards a future high-resolution optical characterization technique for simultaneous corneal surgery and wound healing of the human eye.