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.

 

 

“Queen of Carbon Science” Mildred Dresselhaus Dies

Screen Shot 2017-02-22 at 17.20.21.pngMildred S. Dresselhaus, the Massachusetts Institute of Technology (MIT) physicist known as the “Queen of Carbon Science,” died at the age of 86 years in Cambridge, Massachusetts on Monday, February 20, 2017. She was the first woman at MIT to attain the rank of full, tenured professor, and the first woman to receive the National Medal of Science in Engineering.

Dr. Dresselhaus spent her career studying the properties of carbon and was instrumental in developing carbon nanotubes, which have shown promise in the creation of better electricity conduction and stronger materials. She also contributed to the development of thermoelectric materials, which can transform temperature difference into electricity.

Read her autobiographical article in the 2011 Annual Review of Condensed Matter Physics.

Vision Science: How Do We See in 3D?

How do we see in 3D when we start with a 2D projection on our retinas? How can a flat painting give the illusion of depth and perspective?

In the video describing his latest article in Annual Reviews, Andrew Welchman, a researcher at the University of Cambridge, explains how our neurons put all this information together to produce 3D views.

Read the full article from the Annual Review of Vision Science.

Runners-Up for Person of the Year: CRISPR Scientists

Time Magazine named U.S. President-Elect Donald Trump its 2016 Person of the Year, but amongst the runners-up are the scientists who identified the mechanisms and developed the technique of gene editing using clustered regularly interspaced short palindromic repeats (CRISPR), as well as those who are attempting to find direct applications in human health.

The implications are significant for the treatment of diseases with genetic components. If gene sequences can be altered, they can also be corrected to eliminate the risk of illnesses such as cystic fibrosis or Huntington’s Disease. They can also be used in the treatment of certain cancers. The technique is all the more revolutionary because it is cheap, very accurate, and easy to use.

While many of the scientists involved in these discoveries co-signed a letter urging caution in the use of CRISPR, wary as they are of genome modifications that could be passed on to offspring, this new technology also offers a lot of hope for many diseases that have not yet found a cure.

Jennifer Doudna, of the University of California at Berkeley, along with Emmanuelle Charpentier of the Max Planck Institute, developed a way to simplify this technology and apply it to all kinds of DNA. Feng Zhang, of the Massachusetts Institute of Technology, showed it was possible to use it on human DNA. Carl June, of the University of Pennsylvania, is now attempting to harness CRISPR to treat cancer.

Congratulations to all of them.

Browse Dr. Doudna’s articles for Annual Reviews:

U.S. Public Opinion and the Environment

Two authors scheduled to write for the 2017 Annual Review of Political Science signed a piece in the Washington Post exploring how much resistance U.S. President-Elect Donald J. Trump’s appointee to the Environment Protection Agency (EPA) may face.

Citing work they have done for the next volume of our journal, Political Scientists Patrick J. Egan, of New York University, and Megan Mullin, of Duke University, show that of all the issues, the environment is where the political divide between Republicans and Democrats is starkest. While polarization has been growing between left and right, they most disagree on spending to protect the environment, above the reduction of poverty, childcare, schools, and science.

They conclude that President-Elect Trump’s nominee for the EPA, Scott Pruitt, while being the most conservative appointment for the agency since 1981, will probably not see much political resistance for his agenda to reduce regulation to curb climate change.

MIT Astrophysicist Sara Seager Profiled in NYTimes

Sara Seager, astrophysicist and planetary scientist at the Massachusetts Institute of Technology (MIT) and contributing author of the Annual Review of Astronomy and Astrophysics, was interviewed in The New York Times Magazine of Dec. 7, 2016.aa480631-f16

Dr. Seager’s work has taken her to seek exoplanets—planets that orbit stars outside our own solar system—and, more specifically, exoplanets that would share characteristics with Earth. A rocky planet that would be far enough from its star that its water would be liquid and life on it possible.

Her research allowed for the discovery of the first exoplanet atmosphere. Using light, she is able to identify the elements and gases that exist in these atmospheres. The ultimate goal, she says, is to determine whether we are alone in the universe.

Read Dr. Seager’s article for the 2010 Annual Review of Astronomy and Astrophysics:

Seven Annual Reviews Authors Win Breakthrough Prizes

The 2016 Special Breakthrough Prize in Fundamental Physics was awarded to Kip S. Thorne, of the California Institute of Technology (CalTech), and Rainer Weiss, of the Massachusetts Institute of Technology. They lead the LIGO Project with CalTech’s Ronald W.P. Drever, also a recipient of the prize, and they share this honor with the other 1012 who were part of this research. Together they were the first to detect the gravitational waves predicted by Albert Einstein.

Find Dr. Thorne’s article in the 1972 Annual Review of Astronomy and Astrophysics:

Find Dr. Weiss’ article in the 1980 Annual Review of Astronomy and Astrophysics:

Five Breakthrough Prizes in Life Sciences were awarded in 2017, to the following laureates:

Stephen Elledge, of the Howard Hughes Medical Institute, Harvard Medical School, and Brigham and Women’s Hospital, “for elucidating how eukaryotic cells sense and respond to damage in their DNA and providing insights into the development and treatment of cancer.”

Dr. Elledge is scheduled to write an article for the 2017 Annual Review of Cancer Biology.

Harry F. Noller, of the University of California, Santa Cruz, “for discovering the centrality of RNA in forming the active centers of the ribosome, the fundamental machinery of protein synthesis in all cells, thereby connecting modern biology to the origin of life and also explaining how many natural antibiotics disrupt protein synthesis.”

Find Dr. Noller’s articles in the Annual Review of Biochemistry:

Roeland Nusse, of Stanford University and the Howard Hughes Medical Institute, “for pioneering research on the Wnt pathway, one of the crucial intercellular signaling systems in development, cancer and stem cell biology.”

Find Dr. Nusse’s articles in the Annual Review of Cell and Developmental Biology:

• Yoshinori Ohsumi, of the Tokyo Institute of Technology, “for elucidating autophagy, the recycling system that cells use to generate nutrients from their own inessential or damaged components.” This comes two months after Dr. Ohsumi won the 2016 Nobel Prize in Physiology or Medicine.

Find Dr. Ohsumi’s articles in the Annual Review of Cell and Developmental Biology:

Huda Y. Zoghbi, of the Baylor College of Medicine, Texas Children’s Hospital, and Howard Hughes Medical Institute, “for discoveries of the genetic causes and biochemical mechanisms of spinocerebellar ataxia and Rett syndrome, findings that have provided insight into the pathogenesis of neurodegenerative and neurological diseases.”

Find Dr. Zoghby’s articles in the Annual Review of Neuroscience, the Annual Review of Physiology, and the Annual Review of Genomics and Human Genetics:

How Social Science Can Help Shape Election Law

In this video, Richard Holden, Professor of Economics at UNSW Australia Business School, and author of this comprehensive review, sheds light on the democratic process and the surprising factors that influence how people vote.

The review presents existing social-science research that helps us think through the voting process, including how electoral boundaries are drawn, the redistricting process, what might explain the high incumbent reelection rate in the United States, and how geography influences voting. All this has particular relevance in today’s context of highly polarized and partisan politics that encourages nefarious practices like gerrymandering to win votes. Professor Holden’s review suggests that social science can be a powerful tool to inform election law and support a healthy and transparent democratic process in an increasingly complex political climate.

Learn more with this article, which we’ve made freely available:

Free Trade and the U.S. Election

2908273630_bd93cee6f3_zAs we approach the end of the 2016 presidential campaign in the United States, we explore one of the most heatedly discussed issues: international trade and the various trade deals the country has entered.

Hillary Clinton, the Democratic Party’s nominee, has been criticized by Donald Trump, the Republican Party’s nominee, for her support of the North American Free Trade Agreement (NAFTA), signed in 1994 between the U.S., Canada, and Mexico by her husband, then-U.S. President Bill Clinton. During her tenure as Secretary of State under President Barack Obama, she spoke in favor of the Trans-Pacific Partnership (TPP), a proposed deal between 12 countries of the Pacific Rim that has become a priority for the current administration.

Secretary Clinton now says NAFTA didn’t live up to its potential and will need to be renegotiated—a promise made by the Obama campaign in 2008, which his administration didn’t keep. She also says that the latest version of the TPP, which would cover 40% of the global economy with approximately 800 million consumers, doesn’t meet her “high bar” for “creat[ing] American jobs, rais[ing] wages and advanc[ing] our national security.”

Another proposed deal in the early stages of the negotiating process is the Transatlantic Trade and Investment Partnership (TTIP), between the European Union and the United States, covering a third of global trade.

Mr. Trump, on the other hand, has built his platform on a blanket rejection of free trade.

As the political tide seems to have turned toward protectionism, World Trade Organization Director General Roberto Azevedo has expressed concern about the anti-trade rhetoric on both sides of this campaign. With election day looming, what can we learn about trade deals, regional and global, and their long-term effects on participating economies, specifically on poverty, the environment, and public health? Do they result in net gains or net losses?

Learn more with these five articles, which we’ve made freely available:

Photo credit.

Fighting the Tobacco Epidemic

On November 1, France launched “Moi(s) sans tabac” (“month/me without tobacco”), the very first national campaign of its kind, which will use all existing social media and digital tools to encourage smokers to quit. Inspired by the UK’s “Stoptober” campaign, which started in 2012, it sets the goal of stopping for the entire month of November, 30 days without smoking, which multiply the chances of quitting by five.

9786177825_73ed90e5fb_zUsers can sign up online to join the community and get personalized advice; call a phone number where they can talk to smoking cessation specialists; or download an application that can track their progress, cheer them on, and calculate their savings. On November 1, over 130,000 smokers had signed up.

It is estimated that tobacco is as addictive as heroin, with approximately 60% of those who try it becoming addicted. Of regular smokers, experts calculate that about half will die of smoke-related consequences. In France, there are around 73,000 smoke-related deaths each year. In 2003, a government report found that France’s male population had the highest level of cancer-related deaths, more than any country in the European Union, caused directly by cigarette use.

How did this tobacco epidemic begin? What are some environmental factors that play into tobacco addiction? What are some intervention that have been effective in helping smokers quit?

Read more about tobacco and health here:

Photo credit.