Making Realistic 3D Printed Organs to Plan Surgery

What if a surgical model not only could mimic the look and feel of a patient’s organ but also give surgeons quantitative feedback as they use it to practice the procedure? A team of scientists in the McAlpine Research Group at the University of Minnesota have been trying to answer this question, creating a prostate model that accomplishes exactly that.

In their article for the Annual Review of Analytical Chemistry, titled “3D Printed Organ Models for Surgical Applications,” Kaiyan Qiu, Ghazaleh Haghiashtiani, and Michael C. McAlpine from the University of Minnesota, review current materials used in 3D printed patient-specific organ models used in surgical pre-planning, as well as the state-of-the-art materials and techniques that allow them to replicate many kinds of human tissue.

The use of 3D models in medicine and anatomy is not new. Centuries ago, they were fashioned out of clay, wax, wood, glass, plaster, or even ivory, and they served as teaching tools or as illustrations of the mechanisms of disease, without having to resort to human dissection.

More recently, the boom in 3D printing technology has allowed medical professionals to visualize organs that might require surgery. Using data collected with imaging techniques such as CT scans, MRIs, or ultrasounds, these models can be fabricated to the exact specifications of a person’s organ.

This is of vital importance. A recent study has shown that an average of more than 250,000 people die each year in the United States as a result of medical errors, including more than 4,000 “never events” in surgery — events that should never have happened. Although complete elimination of errors is impossible, proper surgical planning and rehearsal can be key to reducing their occurrence. Model organs are quickly becoming invaluable tools to help prepare for surgery, not just allowing doctors to get a better feel for the organ on which they must operate, but also letting them plan the procedure. Recently, a 3D printed model of a patient’s hip joint changed the surgical team’s minds about the best treatment plan and resulted in performing a hip replacement instead of reconstruction of the damaged hip joint.

Current materials used in 3D printing have limitations, however. Compared to 2D slices of MRI or CT scans, 3D hard plastic models have helped increase the accuracy of surgeons by helping them to visualize the organ. They can also help inform the patients about their conditions and show inexperienced surgeons what to expect from the operation. Their main flaw is that they are not pliable enough to allow for surgical rehearsal. In contrast, rubber-like materials can provide a tactile feel closer to the actual organ they are meant to model and allow for cutting and suturing, but their properties do not precisely match those of an actual organ in elasticity, hardness, or color.

“These present the correct anatomy, but they’re incapable of providing quantitative feedback or even accurate tactile sensation,” said Dr. Qiu, a postdoctoral researcher in the McAlpine group and lead author of the article.

To remedy this, the three co-authors and their team have developed silicone-based 3D printing materials, or “inks,” that can be finely tuned to mimic these properties. Using a customized direct-write assembly 3D printer with a fine nozzle, they were able to construct a prostate model whose dimensions were obtained with MRI imaging and whose physical properties were established by mechanical tests on actual patient prostate samples, which informed their inks.

Screen Shot 2018-03-28 at 11.52.08They were also able to print and integrate electronic sensors onto and within the model that, when connected to a computer, provided quantitative feedback. This capability could enhance surgical precision in an actual procedure, as well as help train surgeons for steadiness, flexibility, and dexterity, just like a high-tech game of “Operation,” where a loud buzz goes off every time the player is too heavy-handed.

“When surgeons practice using different surgical tools, they can know how much force to apply as they get real-time feedback,” said Dr. Qiu. “They can adjust it and use that knowledge in real surgery to avoid damaging tissue.”

They’re not stopping there, setting their sights on more complex 3D models. Some could account for different types of tissue simultaneously printed with different inks. “We could replicate cancerous tissue and healthy tissue within the same model,” says Ms. Haghiashtiani. Another direction is to develop dynamic models, such as a 3D printed heart that can beat like a real one. A third idea is to create models that integrate sensors capable of taking various types of measurements at once, like temperature and multidirectional pressure.

Ultimately, they say, it is possible that their models could replace real organs.

“We are also working on bioprinting, where we can print organs that can replicate biological functions,” said Dr. Qiu.

“If we could get to this point, if we have the technology, you could say ‘why not use this for transplants?’” added Ms. Haghiashtiani.

Read more about prior limitations, current progress, and future perspectives in this important area in their Annual Review of Analytical Chemistry article. 

The Annual Review of Analytical Chemistry, first published in 2008, provides a perspective on the field of analytical chemistry. The journal draws from disciplines as diverse as biology, physics, and engineering, with analytical chemistry as the unifying theme.

 

 

Connect With Our Experts using Remarq

We are pleased to announce a partnership with Remarq, a new scholarly collaboration network from RedLink, that facilitates online annotation and encourages informed conversation between readers, authors, and editors. To use this new service, sign up here.

Annual Reviews President and Editor-In-Chief Richard Gallagher said:

“We are excited to introduce the Remarq scholarly collaboration network on the Annual Reviews site. Remarq promotes informed discussion and teaching by facilitating annotation of our articles. You can make your comments available to the entire audience or restrict them to personal use. A group sharing option will soon be added. I encourage all users to sign up. It truly is an opportunity to ‘Connect With Our Experts’.”

Watch this two minute video to find out how it works:

  1. Readers register with Remarq, using your ORCID, LinkedIn credentials, or email address.
  2. Authors may register with Remarq and then claim their articles. Remarq will alert authors every time a reader posts a question or comment in relation to their article.
  3. Users can make annotations and notes that are either private or public.  In the coming weeks, Remarq will also add a feature to allow the creation of collaborative groups.
  4. To maintain an appropriately high level of discourse on our site, we are drafting guidelines for constructive engagement.
  5. Article sharing is encouraged and permitted within the Remarq network and participants may do so without fear of breaking copyright rules.
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We will be writing to all our authors soon to encourage them to register, but if you want to get started now you can sign up here.

About. Annual Reviews is a nonprofit publisher dedicated to synthesizing and integrating knowledge for the progress of science and the benefit of society. To find out how we create our highly cited reviews and stimulate discussion about science, please watch this short video. Members of the media can visit our Press Center to sign up for journal access.

Eugene Garfield – 1925-2017 – a life of impact

Eugene Garfield. May 9th, 2007.

By Richard Gallagher, President and Editor-In-Chief of Annual Reviews. 

It is with great sadness that I write to share the news that Dr. Eugene Garfield, one of the longest serving members of the Annual Reviews Board of Directors, passed away yesterday (26th February 2017) at the age of 91. Throughout his tenure Gene provided invaluable and enthusiastic support to us.

That Gene’s life created an impact is undisputed.

He first mentioned the idea of an impact factor in science in 1955 and an article in JAMA tells the story of how he and Irving H. Sher created it. In research that he conducted in the late 1950s, he developed the concept of citation analysis, which provided researchers with a powerful network to identify, connect and retrieve information, decades before the internet.

Although he was an information scientist at heart, Gene’s entrepreneurial flair is revealed in a catalogue of highly successful business ventures. The products that he developed from this research, including Current Contents and the Science Citation Index, are still in use today. Gene founded a very successful business, the Institute for Scientific Information (ISI), to produce these products and they were for many years part of Thomson Reuters until their IP and Science business was bought out in 2016 (now Clarivate Analytics). 

His influence extended well beyond scientific information.  Google co-founders Larry Page and Sergey Brin acknowledged Gene in their academic work on PageRank, the algorithm that powers their company’s search engine, leading Gene to be described as “the grandfather of Google.”

My relationship with Gene and his wife Meher goes back prior to my arrival at Annual Reviews in May 2015. I was privileged to work with him between 2002 and 2010 as Editor and Publisher at The Scientist, a professional magazine for life scientists that Gene founded in 1986. He had boldly envisaged it as a daily newspaper for scientists distributed at campuses across the country, and we brought his vision to reality with The Scientist Daily, launched a decade ago. Ellis Rubinsten, an early employee of The Scientist who became Editor of Science, says that Gene’s encouragement of great science journalism ended up transforming both Science and Nature’s research coverage.

Gene was also a pioneering employer. The ISI office had a state-of-the-art childcare facility attached, maximizing convenience for the staff. And he trained and supported many of the female leaders in the publishing industry today. The awards that he inspired also give an indication of his interests, including The Eugene Garfield Residency in Science Librarianship and the ALISE Eugene Garfield Doctoral Dissertation Competition. He also supported and was a Board Member of Research!America.

News of a memorial service will be forthcoming and we will share it here. All of us at Annual Reviews offer our sincere condolences to his family. We are grateful for his life. He will be greatly missed. 

Image credit: Chemical Heritage Foundation to Wikimedia Commons. CC BY-SA.

In Conversation with Barry M. Staw, of Berkeley-Haas

Barry M. Staw, Professor Emeritus at the Haas School of Business at the University of California, Berkeley, talks to Frederick P. Morgeson, Professor at the Eli Broad College of Management at Michigan State University and Editor of the Annual Review of Organizational Psychology and Organizational Behavior.

In this conversation, Dr. Staw discusses the inspiration behind his work on escalation of commitment, a construct he formulated based in part on his family history and, later, studying the nature of the U.S.’ engagement in the Vietnam war. He also gives advice to younger researchers, from where to find inspiration for research and staying grounded in reality to preserving a unique voice in research articles.

Watch the video series here.

Group Affect

We always think of emotions as an internal feelings. Research, however, shows that emotions are contagious, and can spread quickly amongst co-workers.

Studies have even demonstrated that shared positive and negative emotions influence productivity. So how does emotional contagion help maintain group cohesiveness in a professional environment, and how can leaders cultivate positive affect for better results?

Sigal Barsade and Andrew Knight discuss their work in their article on group affect and its accompanying animated video:

Group Affect from Annual Reviews on Vimeo.