Experimental study of thermal damage to in vitro skin tissue welding by femtosecond laser

This study aims to investigate and evaluate the thermal damage changes during femtosecond laser welding in vitro skin tissue. Based on the orthogonal test, a grey-scale co-occurrence matrix was used to extract the textural characteristic values of the microscopic tissue and to find the correspondence between the peak temperature and the textural characteristic values of the in vitro skin tissue. The statistical analysis software Minitab was used to design an orthogonal test, with laser power, laser scanning speed, off-focus amount, and laser scanning times as independent variables and the degree of thermal damage of in vitro skin tissue as the dependent variable, to establish the association between the four influencing factors and the degree of thermal damage. The microstructure of the laser-welded in vitro skin tissue is close to normal tissue with little thermal damage and high tensile strength when the laser power is 14 W, the scanning speed is 50 mm/s, and the off-defocus amount is −1mm, and the laser scanning times are 75. Extreme difference analysis was used to identify significant parameters impacting heat damage in skin tissue, and the associated mechanisms were analyzed. This research can be utilized to better understand and improve the quality of ultrashort pulse laser welding to biological tissues.