Computer-assisted CO2 laser scanning system for surgical techniques

Since the introduction of CO 2 laser in surgery, various techniques such as laser pulsing, beam scanning and computer-assisted laser pulse generator have been applied for the purpose of reducing tissue carbonization (char) and thermal necrosis. Using a computer-assisted optical scanner, it is possible to sweep a focused CO 2 laser beam over a tissue area from several mm 2 to several cm 2 , with a dwell time on each tissue point of less than 1 ms and a resolution of (2 N ) 2 points, where N is the data bit number of the electronic servo drive. In this case, a quite simple optical scanner equipped with two galvanometric driven mirrors placed at 90 degree(s) in respect to XY scanning directions and an appropriate software to process the scanning data via a DA converter, enables a scanning operation with a linearity better than 1% for a maximum angular deviation of 20 degree(s). Because the scanning quality of the laser beam in surgical techniques is assured not only by the precise movement of the laser beam in the operating field, but also by beam characteristics in the focal point, laser beam cross distribution and dwell time, a special software was developed to provide the surgeon with an application-optimized surgical device.