Bioprostheses formed from xenopericardium have been extensively used in cardiovascular surgery. Xenopericardium cutting is performed with scissors, a scalpel or a nibble matrix, though all these techniques don´t provide high-quality accuracy. The purpose of the study was to evaluate the possibility of laser-based technologies application for biomaterial cutting in cardiovascular bioprostheses production.
Materials and methods
The study used a bovine pericardium, preserved with ethylene-glycol diglycidyl ether without any damage to collagen matrix. At the 1st stage xenopericardium cutting was performed using Nd:YAG and Er:YAG solid-state lasers as well as scissors, a scalpel and a nibble matrix. At the 2d stage СО2 laser, generating continuous radiation. was used. The pericardial structure assessment before and after the cutting was done using light microscopy.
Results: In the marginal zone of the pericardium collagen dissociation up to 40 um was found in scissors and scalpel cutting and up to 5 um in nibble matrix cutting. The mean Nd:YAG laser emission power of 5-9 W didn´t allow cutting the pericardium through. Destructive changes such as collagen homogenization and dissociation as well as fibrocyte breakdown were observed up to 60 um from the cutting line. The increase in the mean laser emission power up to 12 W let cut xenopericardium through, however it led to the enlargement of destructive changes area up to 80 um. The study showed that Er:YAG and CO2 laser emission didn´t cause any destructive changes of the pericardium around the cutting area while dissecting the tissue. The cutting speed reached 80 mm/min using Er:YAG laser and this speed increase resulted in lower cutting quality. СО2 laser use allowed the speed increase up to 400 mm/min.
Conclusion
The use Er:YAG and CO2 laser emission for the epoxy-treated xenopericardium cutting not having any mechanical or high-temperature impact on the tissues around the cutting area. The use of СО2 laser lets improve cardiovascular bioprostheses production.
The work is submitted to the International Scientific Conference «Lasers in science, engineering, medicine», Andorra, March 9-16, 2011, came to the editorial office оn 31.01.2011.