

Now, you can hold a copy of your brain in the palm of your hand
This 3D-printed model of Steven Keating's skull and brain clearly shows his brain tumor and other fine details thanks to the new data processing method pioneered by the study's authors. Credit: Wyss Institute at Harvard University


"It never occurred to us to use this approach for human anatomy until Steve came to us and said, 'Guys, here's my data, what can we do?" says Ahmed Hosny, who was a Research Fellow with at the Wyss Institute at the time and is now a machine learning engineer at the Dana-Farber Cancer Institute. The result of that impromptu collaboration—which grew to involve James Weaver, Ph.D., Senior Research Scientist at the Wyss Institute; Neri Oxman, Ph.D., Director of the MIT Media Lab's Mediated Matter group and Associate Professor of Media Arts and Sciences; and a team of researchers and physicians at several other academic and medical centers in the US and Germany—is a new technique that allows images from MRI, CT, and other medical scans to be easily and quickly converted into physical models with unprecedented detail. The research is reported in 3-D Printing and Additive Manufacturing.

"I nearly jumped out of my chair when I saw what this technology is able to do," says Beth Ripley, M.D. Ph.D., an Assistant Professor of Radiology at the University of Washington and clinical radiologist at the Seattle VA, and co-author of the paper. "It creates exquisitely detailed 3-D-printed medical models with a fraction of the manual labor currently required, making 3-D printing more accessible to the medical field as a tool for research and diagnosis."

Imaging technologies like MRI and CT scans produce high-resolution images as a series of "slices" that reveal the details of structures inside the human body, making them an invaluable resource for evaluating and diagnosing medical conditions. Most 3-D printers build physical models in a layer-by-layer process, so feeding them layers of medical images to create a solid structure is an obvious synergy between the two technologies.


The new method described by the paper's authors gives medical professionals the best of both worlds, offering a fast and highly accurate method for converting complex images into a format that can be easily 3-D printed. The key lies in printing with dithered bitmaps, a digital file format in which each pixel of a grayscale image is converted into a series of black and white pixels, and the density of the black pixels is what defines the different shades of gray rather than the pixels themselves varying in color.



"Our approach not only allows for high levels of detail to be preserved and printed into medical models, but it also saves a tremendous amount of time and money," says Weaver, who is the corresponding author of the paper. "Manually segmenting a CT scan of a healthy human foot, with all its internal bone structure, bone marrow, tendons, muscles, soft tissue, and skin, for example, can take more than 30 hours, even by a trained professional—we were able to do it in less than an hour."

The researchers hope that their method will help make 3-D printing a more viable tool for routine exams and diagnoses, patient education, and understanding the human body. "Right now, it's just too expensive for hospitals to employ a team of specialists to go in and hand-segment image data sets for 3-D printing, except in extremely high-risk or high-profile cases. We're hoping to change that," says Hosny.

In order for that to happen, some entrenched elements of the medical field need to change as well. Most patients' data are compressed to save space on hospital servers, so it's often difficult to get the raw MRI or CT scan files needed for high-resolution 3-D printing. Additionally, the team's research was facilitated through a joint collaboration with leading 3-D printer manufacturer Stratasys, which allowed access to their 3-D printer's intrinsic bitmap printing capabilities. New software packages also still need to be developed to better leverage these capabilities and make them more accessible to medical professionals.

Despite these hurdles, the researchers are confident that their achievements present a significant value to the medical community. "I imagine that sometime within the next 5 years, the day could come when any patient that goes into a doctor's office for a routine or non-routine CT or MRI scan will be able to get a 3-D-printed model of their patient-specific data within a few days," says Weaver.

Keating, who has become a passionate advocate of efforts to enable patients to access their own , still 3-D prints his MRI scans to see how his skull is healing post-surgery and check on his brain to make sure his tumor isn't coming back. "The ability to understand what's happening inside of you, to actually hold it in your hands and see the effects of treatment, is incredibly empowering," he says.


Explore further

Custom 3D-printed models help plastic surgeons plan and perform rhinoplasty

More information: Ahmed Hosny et al, From Improved Diagnostics to Presurgical Planning: High-Resolution Functionally Graded Multimaterial 3D Printing of Biomedical Tomographic Data Sets, 3D Printing and Additive Manufacturing (2018). DOI: 10.1089/3dp.2017.0140
Provided by Harvard University
Citation: New 3-D printing technique enables faster, better, and cheaper models of patient-specific medical data (2018, May 30) retrieved 2 August 2021 from https://phys.org/news/2018-05-d-technique-enables-faster-cheaper.html

Feedback to editors

User comments