Imaging of acoustic waves induced by excimer laser ablation of the cornea

In the present study a pump-and-probe imaging set up was arranged to image and analyze the evolution of pressure waves induced by ArF ablation of the cornea, during their propagation into the eyeball. In vitro experiments simulating the effects of clinical PRK have been performed by using an artificial model of the human eyeball, composed of a cell filled with hyaluronic acid gel with a sample of freshly excised bovine cornea placed on the gel surface. Laser irradiation was provided at a fluence of 180 mJ/cm(2). Irradiation spot diameters were varied in the range 2.0-5.0 mm. Images of the traveling acoustic waves evidenced diffraction effects, related to the diameter of laser spots on the corneal surface.