Reaching into a beat-up, red-and-white cooler lined with a white terry-cloth towel, Dr. Matthew Bramlet pulls out a replica of an infant's heart.
The size of a small pear and chalky to the touch, the model was made in a 3-D printer. Last spring, Dr. Bramlet, 38, a pediatric cardiologist at Children's Hospital of Illinois in Peoria, commissioned it from the hospital's new innovation lab while planning surgery for a girl with a congenital heart defect. Constructed using images from the patient's MRI scans and printed with polymer powder and liquid glue, it duplicates nearly every detail of the original—including a critical element that an echocardiogram, CT scan and MRI had all missed in their two-dimensional incarnations: Deep inside the 9-month-old's heart were many, many more holes.
Shocked by what he was seeing, Dr. Bramlet immediately showed his findings to the patient's cardiac surgeon, Dr. Randall Fortuna, 47. “We scratched our heads before surgery and asked if it was real,” Dr. Fortuna says. If this replica was telling the truth, the surgery they had planned potentially would be harmful. It was clear they needed a plan B.
In recent years, 3-D printing, also known as additive manufacturing, has been ballyhooed as a game-changing technology because of its ability to make customized objects with no additional tooling or material waste. The process, involving a machine rapidly layering materials to make an object from a digital model, has made inroads in industries from aerospace to consumer electronics.
The technology was developed in the 1980s mainly to produce small volumes of scale models; much attention lately has focused on hobbyists printing functional guns. But the shift from the garage to the factory floor has begun. Additive manufacturing is poised to almost triple in value to about $6 billion annually worldwide by 2017, according to one estimate, boosted in part by a recent decision by General Electric Co. to spend tens of millions of dollars “printing” fuel nozzles for its newest jet engine.
But adoption of 3-D printing is happening fastest in the medical industry. Commercially, companies such as Beltone, a Glenview-based hearing-aid maker, uses 3-D printing to make the majority of its hearing aids, and Kalamazoo, Mich.-based Stryker Corp. uses it to produce knee implants. With the Midwest's cluster of research institutions and manufacturing expertise, this region is emerging as fertile ground for developing clinical uses for 3-D printing.
There are still significant regulatory hurdles to the widespread use of 3-D implants and prosthetics, though. So the technology's most immediate impact is on personalized surgery and pre-surgical planning. The ability to create a 3-D print directly from CT scans and MRIs allows Drs. Fortuna and Bramlet, and others like them, an unprecedented level of insight into a patient's anatomy before ever setting scalpel to skin.
“The overall direction is to make complex operations simpler,” says Dr. Bohdan Pomahac, 43, a plastic surgeon at Brigham & Women's Hospital in Boston and a pioneer in facial transplants who uses 3-D printing to plan his surgeries. “This may be one of the most profound tools that we hope to use in the coming future.”
In August 2011, Dr. Katherine Barsness walked into the innovation lab at Northwestern University's Feinberg School of Medicine and saw a small 3-D printed ribcage taped to the wall. It was a eureka moment of sorts for the training of doctors. A pediatric surgeon and assistant professor at Feinberg specializing in minimally invasive surgery, she had been frustrated by the traditional pediatric surgical teaching tool—live pigs. Aside from the ethical quandaries involved in using live animals, their size and anatomy were a poor substitute for a newborn baby.
Nine months after setting eyes on the plastic ribcage, Dr. Barsness, 44, was filing a provisional patent for a true-to-size newborn ribcage with silicon skin made from 3-D printed molds. Inside, she placed fetal bovine tissue from slaughterhouses, surgically altered to create the exact birth defect surgeons must correct during training. “Having the actual anatomy is moving us so many steps into the future,” she says.
At a recent training session in the innovation lab, Dr. Barsness hovers as two Northwestern surgical fellows work on the simulation models. “Don't poke the liver,” she says to Eric Grossman, a second-year fellow reconnecting an esophagus to a stomach. “The entire operation happens within the space of an egg,” she notes.
Dr. Alexander Dzakovic, 42, a pediatric surgeon at Loyola University Health System helping Dr. Barsness with the day's training, sums it up: “You don't want their learning curve to be in the patient.”
Despite growing enthusiasm for the use of 3-D printing in medical training, cost is a significant obstacle. “The disadvantages are that it's not covered by insurance yet, the software is expensive, you need a lab and you need a strong collaboration between the surgical and radiology departments,” says Dr. Frank Rybicki, 47, a radiologist and the director of the Applied Imaging Science Laboratory at Brigham & Women's Hospital.
“There is tremendous interest,” says Dr. John Hibbeln, 55, a radiologist at Rush University Medical Center who runs the hospital's three-month-old 3-D printing lab. “The question is now that of modern medical economics. How do we pay for these? These are not inexpensive devices.”
High-resolution printers run from about $40,000 to upward of $1 million, and federal funding is increasingly difficult to obtain. The National Institutes of Health awarded money in the 2013 fiscal year to only 17 percent of applicants, the lowest rate since at least 1997, according to data from the Bethesda, Md.-based agency.
Most of the research on the clinical use of 3-D models is financed by universities and foundations. Dr. Barsness has received nearly $300,000 in grants from the junior board of the Ann & Robert H. Lurie Children's Hospital of Chicago Research Center, the Feinberg school and the Children's Surgical Foundation.
The lab that printed Dr. Bramlet's infant heart was funded by Chicago-based trading firm Jump Trading LLC. The company donated $25 million to create the Jump Trading Simulation and Education Institute in Peoria. The 67,000-square-foot facility opened last April in partnership with the University of Illinois College of Medicine and OSF Healthcare. In February, Jump Trading donated another $25 million to fund a joint medical research project between Jump and the University of Illinois at Urbana-Champaign's College of Engineering. About a quarter of the institute's $3 million annual budget is devoted to innovation, with $150,000 of that devoted to 3-D research.
When he can sit still, Dr. Pravin Patel, a pediatric plastic surgeon at the Craniofacial Center at the University of Illinois and Shriners Hospitals for Children, works so closely with his resident bioengineer and director of research, Linping Zhao, that they share an office. Together, they map out surgeries for some of the Midwest's toughest cases of facial and cranial reconstruction.
For Dr. Patel, 55, personalizing surgery with the help of 3-D printed models is invaluable. “In the past, you would do it on the table,” he says. “This was a breakthrough for surgeons because now you could hold it in your hand, cut it up, move it around. You can rehearse your operation.”
Dr. Patel holds a plastic 3-D printed model of a patient's fibula and skull. The patient was born without an eye and ear, as well as part of her jaw, eye socket and cheekbone, so Dr. Patel and Mr. Zhou are planning a surgery that uses part of the fibula to reconstruct the jaw and face. Using the model, they map out the surgery, cut by cut, and commission printed “surgical jigs,” or cutting templates, that will offer a road map in the operating room.
Medical Modeling Inc., a contract 3-D printing firm in Golden, Colo., has done all of Dr. Patel's printing for years. President Andy Christensen says that when he founded his company 15 years ago, medical modeling for surgery was virtually nonexistent. Today, personalized surgery—customized models, templates and instruments—is the majority of his work. Wohlers Associates Inc. of Fort Collins, Colo., which produces an annual report tracking 3-D technology, estimates that more than 50,000 patients a year worldwide are being treated with guided surgery and 3-D printed instruments. “I think a lot of times things are overhyped,” Mr. Christensen says of the media coverage of 3-D printing. But personalized surgery “deserves the hype.”
On April 10, 2013, at the Children's Hospital of Illinois in Peoria, Dr. Fortuna scrubbed in to operate on the 9-month-old girl with the congenital heart defect. He went into surgery planning to repair the interior pathways of the heart. But with the model in mind, Dr. Fortuna was prepared to perform a different procedure entirely—an interim one that would allow the baby's heart to grow larger before he tried a permanent repair.
In the operating room, Dr. Fortuna opened up the girl's chest and found what the model had shown: more holes. The procedure planned without the 3-D model “would have created a lot of problems.” So Dr. Fortuna did the temporary fix, which included a larger shunt to improve blood flow to the lungs. The child is fine for now but will require more surgery.
Afterward, he went back to his office and dialed Dr. Bramlet. “Matt,” he said, “your heart tells the truth.”"3-D printing is revolutionizing surgery" originally appeared in Crain's Chicago Business.