In a world first, CSIRO researchers have made possible the 3D printing of bespoke stents, a biomedical device used to treat narrow or blocked arteries.
The breakthrough was made in partnership with Wollongong firm Medical Innovation Hub, and is a game changer in the production of self-expanding nitinol stents for Peripheral Arterial Disease (PAD), which affects more than 10 per cent of Australians.
People afflicted with PAD experience the collection of fatty deposits and reduced blood flow in arteries outside the heart – most commonly in the legs. Patients typically experience pain when walking, and may develop gangrene in severe cases.
The home-grown technology has the potential to revolutionise the $16 billion global stent manufacturing industry, says Minister for Industry, Science and Technology Karen Andrews.
“This is a great example of industry working with our researchers to develop an innovative product that addresses a global need and builds on our sovereign capability,” she says.
Until now, surgeons have been forced to use ‘off-the-shelf’ stents for operations.
The ability to 3D print stents could improve sizing options, preserve essential anatomy, and enable diameters and shapes to suit individual patient requirements.
Surgeons could also direct the creation of individual stents on-site, reducing inventory and saving money.
The challenge metallurgists around the world have faced was to find a way to 3D print a self-expandable nitinol stent without compromising the metal’s unique properties.
That problem was cracked by the team at CSIRO’s Lab22 in Melbourne by using a cutting-edge 3D printing process called selective laser melting.
CSIRO principal research scientist Dr Sri Lathabai says the process allows the creation of complex, patient-specific products with high geometric accuracy.
“Nitinol is a shape-memory alloy with superelastic properties,” Dr Lathabai says.
Nitinol is a tricky alloy to work with in 3D printing conditions due to its sensitivity to stress and heat.
“We had to select the right 3D-printing parameters to get the ultra-fine mesh structure needed for an endovascular stent, as well as carefully manage heat treatments so the finished product can expand as needed once inside the body,” he says.
Medical Innovation Hub’s chief executive Dr Arthur Stanton, a vascular surgeon who has treated thousands of patients, saw a need for an improved treatment.
“Currently, surgeons use off-the-shelf stents, and although they come in various shapes and sizes, there are limitations to the range of stents available,” Dr Stanton says.
“We believe our new 3D-printed self-expanding nitinol stents offer an improved patient experience through better fitting devices, better conformity to blood vessel and improved recovery times.
“There is also the opportunity for the technology to be used for mass production of stents, potentially at lower cost.”
A new company, Flex Memory Ventures, has been established to drive commercialisation of the technology.