Excimer laser keratoplasty. Part 1: Basic concepts

A commercially available ophthalmic excimer laser was used with a new "open mask system" to perform noncontact and nonthermal excimer laser keratoplasty in 20 human and 40 pig cadaver eyes. Circular penetrating corneal trephinations and corneal grafts were performed with the excimer laser set at 193 nm. Light microscopy and scanning and transmission electron microscopy of the human and pig eyes demonstrated the high quality of excimer laser trephination (smooth wound margins that were approximately parallel to the optical axis of the eye), and the superior wound configuration and geometry.