1 June 1990 On-off time control of laser pulses for pseudo-constant temperature coagulation in tissue
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Proceedings Volume 1202, Laser-Tissue Interaction; (1990) https://doi.org/10.1117/12.17632
Event: OE/LASE '90, 1990, Los Angeles, CA, United States
Abstract
An open-loop temperature control was introduced to control evolution of the maximum temperature on the tissue surface to be within upper and lower limits. For this purpose, the temperature evolutions of sample shots were analyzed and optimal sequences of laser pulses were computed. The 1.06 tm pulsed Nd:YAG laser was used and the thermal camera measured temperature. Experiment on animals in vivo and in vitro was performed to test the technique. Upper and lower temperature limits during laser irradiation were set below 100 °C since thermal coagulation was ofprimary concern. Usually, difference between the upper and lower limits was set to 1 5°C during experiment. However, this difference depended on the laser specifications such as power, pulse width, and repetition rates, as well as on tissue properties. Coagulation studies showed a clear relation of temperature versus cogulation depth. Therefore, the heating temperature and the duration time can be used as primary parameters instead of laser power and exposure time or energy.
© (1990) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Gilwon Yoon, Gilwon Yoon, Serge R. Mordon, Serge R. Mordon, Jean Marc Brunetaud, Jean Marc Brunetaud, Radouan Faiz, Radouan Faiz, Richard C. Straight, Richard C. Straight, Pierre Yves Bugnon, Pierre Yves Bugnon, Marcel Staroswiecki, Marcel Staroswiecki, J. Leroux, J. Leroux, } "On-off time control of laser pulses for pseudo-constant temperature coagulation in tissue", Proc. SPIE 1202, Laser-Tissue Interaction, (1 June 1990); doi: 10.1117/12.17632; https://doi.org/10.1117/12.17632
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