Using 3D printing and femtosecond laser micromachining to fabricate biodegradable peripheral vascular stents with high structural uniformity and dimensional precision

This study combined rotational 3D printing with femtosecond laser postprocessing to produce a biodegradable polylactic acid (PLA) prototype stent suitable for treating peripheral arterial diseases. First, the peripheral arterial stent structure was designed with the assist of the finite element method. The external diameter of the stent was compressed from 4 to 2 mm for placement in the catheter, and balloon dilation was performed to expand the outer diameter to 5.4 mm. Subsequently, rotational 3D printing was conducted in conjunction with a femtosecond laser to produce and postprocess the designed stent structure. A PLA stent with uniform structural widths, smooth edges, and accurate structural dimensions was successfully produced. The strut width, connector width, and crown radius of the PLA stent were respectively 0.205 mm (standard deviation [SD] = 0.005 mm), 0.203 mm (SD = 0.004 mm), and 0.303 mm (SD = 0.003 mm). Finally, the stent was compressed and expanded to measure its radial force performance after expansion. The fabricated stent achieved the required radial force of 0.079 N/mm and met the required specifications for a peripheral arterial stent.