Vascular stents typically come in a number of different lengths and diameters. The physician implanting these chooses which would best fit individual patients, but often the available sizes are not ideal for certain cases. Researchers at Northwester University turned to 3D printing to be able to create stents of any size, allowing them to be perfectly customized to each patient’s unique anatomy.
They tweaked a technique called projection micro-stereolithography (PµSL), which works by projecting light onto a liquid photo-curable material that quickly solidifies. The new technique is called micro-continuous liquid interface production (microCLIP) and it can be used to print objects with a resolution down to 7 microns, an important characteristic when considering the small size stents.
The Northwestern researchers used a citric-acid based polymer as the building material, which is flexible, biodegradable, and works as an antioxidant. The same polymer can also host drugs, such as rapamycin, that would be released as the stent slowly biodegrades to prevent restenosis.
The printing process is both fast, taking only a few minutes to make a stent, and can be run in parallel to produce many stents at a time. The resulting stents are quite strong, comparable even to metal ones, but don’t require fat struts that are typical of existing biodegradable stents.
Here you can see the process of the stent being printed:
Study in Advanced Materials Technologies: 3D-Printing Strong High-Resolution Antioxidant Bioresorbable Vascular Stents…
