| 摘要 |
<p>Laser-induced fluorescence is generated during ablation of corneal tissue with the argon-fluoride 193nm excimer laser. An intensified charge-coupled device is used to achieve fast per-pulse temporal resolution of laser-induced fluorescence. The epithelium and stroma of a human cornea are subjected to 193nm excimer laser keratectomy. During the procedure, laser-induced fluorescence is measured. Changes in laser-induced fluorescence are detected and used to control the epithelial removal. In each layer two peaks predominated, one at about 405nm and the other at about 346nm. There is a rapid three-fold reduction in the 346nm ultraviolet peak at the transition from epithelium to stroma. By monitoring real-time changes in the measured intensity of laser-induced fluorescence during ablation of corneal tissue by the excimer laser, the transition from phototherapeutic removal of the epithelium to photorefractive reshaping of the stroma may be accurately controlled.</p> |
