When it comes to the future of medicine, its becoming increasingly clear that biomimetics and 3D printing will play an important role. Basically, this amounts to machines that are designed to mimic biology for the sake of making our bodies run better. In addition, it means that both medical machines and organic parts could be created on site, allowing for speedier, accessible and more cost-effective interventions and augmentations.
For example, research being conducted at Harvard’s Wyss Institute for Biologically Inspired Engineering and the Harvard School of Engineering and Applied Sciences has led to the creation of artificial muscle that can imitate the beating motion of the heart – also known as the “Left Ventricle Twist”. This development, which is a big break in the field of biomimetics, could also be a game-changer when it comes to producing artificial hearts.
Their research started with what is known as a pneumatic artificial muscle (PAM), one which was modeled after the striated muscle fibers found in the heart. Made from silicone elastomer and embedded with braided mesh, this artificial heart was then hooked up to an air tube to see how it would handle being inflated. When air was pumped into the PAM, it responded by twisting and thus becoming shorter. This is similar to what the natural fibers of the heart do, which contract by twisting and shortening.
Several of the PAMs were then embedded within a matrix of the same elastomer from which they were made. Through a process of manipulating their orientation to one another, along with selectively applying different amounts of pressure, the researchers were able to get some of the PAMs twisting in one direction, at the same time that others twisted in the opposite direction. As a result, the silicone matrix exhibited the same three-dimensional twisting motion as the heart.
The immediate applications for this are obvious; in short, creating a range of artificial hearts for patients who suffer from severe disorders or heart damage. Unlike conventional artificial hearts, these ones would be able to provide pumping action similar to the real thing. In addition, the PAMs were able to mimic the change in motion that is caused by various heart disorders, and these could be used to help in the research of such conditions, not to mention the development of treatments for them.
Equally exciting are the possibilities being offered by 3D printing which now offers a range of artificial replacements. The latest example comes from the Netherlands, where a 22-year old woman has had the top of her skull replaced with a 3D printed implant. Due to a severe condition that causes a thickening of the skull, the patient was suffering from severe and worsening symptoms. And in a first of its kind procedure, she was given a tailor-made synthetic replacement.
The thickening of the skull puts the brain under increasing pressure. Ultimately, she slowly lost her vision and started to suffer from motor coordination impairment. It was only a matter of time before other essential brain functions would have been impaired and she would have died. So intensive surgery was inevitable, but until now there was no effective treatment for such patients.
So far, 3D printing has been used to produce lower jaw implants, prosthetic arms, legs, and cells (kidney, liver, and skin cells). In this instance, the skull was 3D-modeled and then printed as a single full piece that was able to be slotted and secured into place. Prior to the procedure, Verwej and his team had to familiarize themselves with reconstructions and 3D printing, in particular that which pertained to partial skull implants.
Implants have often been used when part of a skull has been removed to reduce pressure on an patient’s brain. However, Verweij claimed that cement implants are not always a good fit, and that 3D printing allows for exact specifications. As he explained it:
This has major advantages, not only cosmetically but also because patients often have better brain function compared with the old method.
Verweij worked with an Australian company called Anatomics – which uses 3D printing to produce custom-made implants and surgical models for medical practitioners – to produce the replacement skull. The surgery, only just announced, was carried out three months ago and was a success. According to Verweij, the patient has fully regained her vision and has returned to her normal life. The work undertaken on the procedure means that UMC Utrecht is now is a position to carry out other similar work.
The ability to tailor-make synthetic bones, which are exact duplicates to the original, offers exciting possibilities for reconstructive and replacement surgery. It also does away with some rather invasive and unsatisfactory procedures that involve putting shattered bones back together and joining them with pins, bars and screws. And considering that such procedures often require multiple operations, the combination of 3D scanning and 3D printed replacements is also far more cost effective.
And be sure to check out the video below that shows the Utrecht procedure. Be warned, the video contains actual footage of the surgery, and is therefore not recommended for the squeamish! English subtitles are also available via the video controls.