ETH research team develop 3D printed stents

A team from the Swiss Federal Institute of Technology in Zurich (ETH) has collaborated with researchers at University Hospital Zurich and the University of Zurich to develop a stent for upper airway obstruction that generally does not move from its insertion site. They are fully absorbed by the body, as they gradually dissolve. Patients therefore do not have to undergo another surgical procedure for removal. The stents are individually adapted to the patient’s anatomy and 3D printed. 

Tubular stents being used currently are made either of metal and have to be removed surgically or of silicone and often migrate. According to an article from ETH Zurich, the new stents are manufactured from a light-​sensitive resins specially adapted for this purpose. Researchers create a computer tomography image on the basis of which they create a digital 3D model of the stent. The data is then transferred on to the 3D printer.

This manufactures the stents using a process known as digital light processing (DLP). DLP technology has previously just been able to produce stiff and brittle objects. However, this special resin becomes elastic after light exposure. The researchers also included gold in the stent’s structure. This facilitates the use of medical imaging to track its location during insertion. The researchers were able to show through animal testing that the stents are absorbed by the body after six to seven weeks. They were no longer visible on X-​ray images ten weeks after implantation.

The technique can be transferred relatively easily to similar medical applications, explained ETH Professor André Studart. “It is hopefully only a matter of time before our solution finds its way into the clinic.”