Shape transformable bifurcated stents.

Non-invasive delivery of artificial implants, stents or devices in patients is vital for rapid and successful recovery. Unfortunately, because the delivery passage is often narrower than the size of the delivered object, a compromise between the shape that is effective at the targeted location and a thin form that allows smooth unobstructed travel to the destination is needed. We address this problem through two key technologies: 3D printing and shape memory polymers (SMPs). 3D printing can produce patient-customizable objects, and SMPs can change their initially formed shape to the final desired shape through external stimulation. Using these two technologies, we examine the design and fabrication of bifurcated stents. This study presents a mock-up where blood vessels are fabricated using moulded silicon, which supports the effectiveness of the proposed method. The experimental results reveal that a bifurcated stent with a kirigami structure can smoothly travel inside a vessel without being obstructed by branched parts. We believe that this work can improve the success rate of stent insertion operations in medicine.