Pulsed mid-infrared laser ablation of tissue: Photomechanical and photoacoustic effects

We have conducted experiments to investigate the impulse momentum coupling and cavitation induced photomechanical and photoacoustic effects in tissue during mid-infrared laser tissue interaction. We used free-running CTH:YAG and Er:YAG lasers that delivered laser pulses of 250-300 /spl mu/sec duration. The measured pressures in human lenses of various grades for Er:YAG pulse laser emulsification are presented. Flash photographic studies reveal that cavitation bubble dynamics is dependent on laser wavelength, pulse energy and duration, and the physical properties of the fluid in which cavitation takes place.<
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