It is planned to develop a laser plume analysis instrumentation system that is suitable for quantitative measurements on potentially harmful tissue ablation by-products such as toxic vapor species in laser plumes generated by laser surgery procedures. In Phase I, candidate laser plume analysis instruments will be evaluated for their utility in measuring tissue ablation by-products produced by argon fluoride(ArF) excimer laser anterior keratomileusis of animal and human cornea specimens. The candidate laser plume analysis instruments include:(1) spectroscopic instrumentation for characterization of plume vapor species, their emission spectra, and the doses of phototoxic fluorescence emissions absorbed by the retina and other ocular structures;(2) a laser probe attenuation system for spatial and temporal characterization of debris particles; and(3) a mass spectrometer system for characterization of relative abundances of plume vapor species. ArF excimer laser anterior keratomileusis experiments will be performed using laser parameters identical to those presently being evaluated in clinical trials. In Phase II, selected laser plume analysis instruments will be developed and optimized for research and clinical applications. Issues related to routine and dependable use in a clinical environment will be addressed.Awardee's statement of the potential commercial applications of the research:The principal commercial application of this instrumentation system is laser plume analysis of hazardous laser/tissue ablation by-products. The system will be suitable for determination of safe and effective laser surgery procedures and for real-time monitoring of potentially toxic by-products generated during clinical use of laser ablation techniques.National Eye Institute (NEI)