Toys, shoes, dresses, musical instruments, fossil replicas, drones, cars and even houses are all amongst the many things being 3D printed today – there is even a specially designed 3D printer being sent to the International Space Station to be used to create replacement parts in zero-G.
The field of medicine is no exception to this revolution, and a lot of this is driven by medical imaging. In this post I’ve highlighted six ways medical imaging solutions and 3D printing are being used in combination now in the real world and also will be in the near future.
1. Anatomic Models
The first and most obvious application of 3D printing in medicine is to create physical models of anatomic features for education of physicians, patients, and the public. The NIH has a free library of examples of organs, proteins, viruses, bones, and other biological structures all of which are ready to print into 3D plastic models. The anatomical structures were, of course, primarily made from CT or MR scans.
However, printing a general anatomical model is a little different from ordering one from a medical supply company. As Dr. Rajiv Chopra, Associate Professor of Translation Research at UT Southwestern’s Advanced Imaging Research Center, says, “Once you own one example model normal heart, you really don’t need another. That alone certainly does not justify getting a 3D printer.”
Where 3D model printing actually starts to make real sense is when it is used to create a model from a specific patient’s particular anatomy using medical imaging data. This has been shown to be particularly useful when surgeons need to plan complex surgeries.
2. Custom Implants
Medical imaging can also be used with 3D printing to go a step beyond and create not just models, but actual replacement implants customized to exactly fit the patient’s needs.
There have been a number of recent dramatic examples of replacing parts of a patient’s face, skull and cranium with plastic analogs.
Researchers at Peking University have begun 3D printing patient-specific custom vertebrae and implanting them in patients with a range of conditions including cervical spondylosis. In this case titanium was the medium of choice.
Such custom implants need not be permanent. One early success at the University of Michigan involved creating an artificial trachea via 3D printing for an infant at risk of suffocation death due to tracheobronchomalacia. The baby’s body would eventually naturally dissolve and eliminate the material from which the artificial trachea was made, but by that time the child’s own windpipe would have grown strong enough that the risk of fatal obstruction was in the past.
Traditionally manufactured implanted devices like hip and joint replacements can also be improved with 3D printing. The end parts that come in contact with the patient’s skeletal structure can be custom shaped from CT scans to be a perfect fit. Traditionally the orthopedic surgeon would use a saw, chisel, and hammer on the bone to make room for a standard replacement to fit the patient. Now the part can be made to fit the bone instead of simply fitting the custom end pieces.
3. Custom Prosthetics
There are numerous examples of amputees, their friends, their families and volunteers designing and printing customized prostheses that are preferred over available commercial versions. This is also true in parts of the world where advanced electronic prosthetics are difficult to acquire for cost or logistics reasons.
In some cases people are adding flourishes to add a sense of style or fun to something they need but which is usually utilitarian in design.
4. Experimental Medical Devices and Lab Equipment
Another application is for researchers who need to create a device that does not yet exist. Dr. Chopra said, “The ability to create specific equipment parts as needed for your experiments makes a 3D printer an essential part of any research lab.”
There are a number of laboratory component designs available at the NIH 3D Print Exchange web site. However, some researchers have gone beyond fast-tracking lab equipment assembly to the creation of patient-specific mechanical devices to aid physicians in treatment.
As an example of such experimental devices, Dr. Chopra and his colleague Dr. Travis Browning, a Radiologist and Assistant Professor in UT Southwestern’s Department of Radiology, are investigating making patient-specific biopsy guidance devices in order to simplify challenging needle approaches and increase the chance of a successful extraction from the target tissue.
5. Pharmaceutical Delivery Devices
Researchers at Louisiana Tech University have also managed to adapt low-cost printers to create an alternative to the beads often used to implant antibiotics for smart drug delivery. In this case, medical imaging would not be used to custom design the printed devices but would be involved in implantation and tracking.
6. Artificial Organs
While all of the other examples above involve printing objects made of plastic, metal and other non-living materials, there is another kind of 3D printing in the experimental stages that intends to print objects composed of living cells.
While this “bio-printing” technology is still in its infancy, earlier this year researches at the University of Sydney, MIT, Harvard, and Stanford worked together to develop a device that allowed them to successfully print blood vessels. In a TED talk in 2011, Dr. Anthony Atala discussed the potential of this technology to print functioning organs (e.g. kidneys) for transplants instead of having people on long waiting lists for compatible organs to come available from a donor.
Is your organization making any strides in combining medical imaging and 3D printing? If you have an interesting story to share, I’d love to hear from you. Just leave a comment.