This program will evaluate the potential application of the CO2TEA laser as a tool for corneal surgery. An opthalmic laser system using a CO2TEA laser, appropriate delivery system, and controls will be produced. This system will be tested on a variety of corneas, including dead bovine, live rabbits and monkeys, and human eye bank eyes. The quality of the incision will be evaluated using standard histological and ultrastructural examinations to determine the optimum choice of laser power, pulse width, repetition rate, focusing, and slit configurations. Evaluation will be in terms of depth and width of incision, precision of control, and incision speed. The laser surgery will be compared to a diamond-bladed microknife used as a control. The successful conclusion of this work will lead to a safe, reliable, cost-effective surgical tool for the performance of corneal surgery, especially radial keratotomy.National Eye Institute (NEI)