The Application of Laser Micromachining Technology in Biological Application Devices
Application Three
Vascular stent structure processing.
Vascular stent implantation is an effective means of treating vascular diseases such as arteriosclerosis. The expansion of the blood vessel or cavity ensures that blood can flow into the occluded artery in the case of stenosis or occlusion. The stent is usually biocompatible. A tubular mesh structure prosthesis machined from a metal alloy or an organic polymer. Metallic cardiovascular stent implantation is currently the most widely used method for the treatment of coronary artery occlusion.
Most stents are made of metal and remain permanently in the artery after implantation, posing a risk of serious medical complications. In order to avoid such complications, a solution is a bioabsorbable stent made of materials such as poly-L-lactic acid (PLLA) or polylactic acid (PLA), but because of its low melting point, it is extremely sensitive to thermal effects. Bioabsorbable materials are a challenging task, and femtosecond laser processing technology can effectively control the thermal damage of the sample holder structure.
Figure (a) PLLA sheet and (b) partial structure of a femtosecond laser-cut triangular cut structure.
As a non-contact "cold" processing technology that is not limited by materials, laser micromachining greatly reduces the effects of various effects such as melting zone, heat affected zone and shock wave on the surrounding materials. Ultra-short pulse laser machining of the scaffold enables accurate grid structures and smooth cut surfaces to minimize the thermal effects of laser beam energy on the scaffold material. Laser micromachining non-thermal ablation processing methods have fundamentally made bioabsorbable stent technology feasible. However, laser micromachined vascular stents are expensive and have low yield. How to use this technology to realize industrial mass production of vascular stents is an urgent problem for researchers.