Recent Trends and Developments in Excimer Laser Ablation for Medical Applications.

The ArF excimer laser ablates the cornea and other tissue with micrometer-size precision and minimal residual thermal damage. However, there is still no clear picture regarding the mechanisms for the excimer laser ablation (ELA) giving rise to this favorable and characteristic removal of hydrated tissue. In order to gain obvious insight into the role of water in the ELA mechanism of the cornea, we have macroscopically investigated the ablation behavior of gels in the swelled states. The ELA of the hydrated collagen and polyacrylamide gel using ArF laser were scrutinized using time-resolved photography, atomic force microscopy (AFM), and FT-IR attenuated total reflectance spectroscopy (FTIR-ATR). The observed results led us to the conclusion that the control of the water content in and/or on the gel matrix during ELA would reduce any thermal and mechanical damage to the soft tissue.