3-D printer helps doctors prep for complex surgeries
Dr. Joseph Madsen entered the operating room at Boston Children’s Hospital on New Year’s Eve and stood over Myalynn Ranson, a teenager with plans to become a marine biologist and travel the world — if only her violent seizures would stop.
Madsen’s challenge was to remove a chunk of abnormal tissue from the left side of Myalynn’s brain, the likely culprit in the seizures, without damaging her memory or slicing a blood vessel.
As he made the first incision that morning, he felt an extra dose of confidence knowing he had done this very procedure before. He had practiced on an exact replica of Myalynn’s brain produced with a 3-D printer in the basement of Children’s Hospital.
Children’s has embarked on one of the nation’s most ambitious programs to integrate 3-D printing technology into medical care with the aim of avoiding surgical complications, reducing the length of operations, and ultimately cutting costs. The hospital has one printer buzzing 24 hours a day and will add two more, at the cost of $400,000 each, later this year.
3-D printing is the technology of making three-dimensional objects from digital files — in medicine, typically MRI or CT scans. Children’s has produced more than 170 models over the past 18 months, printing not just replica brains, but also skulls, spines, rib cages, and blood vessels.
With these models, surgeons, like baseball players taking batting practice, can make practice cuts before a major surgery.
“We’re trying to reduce surprise,” said Dr. Peter Weinstock, director of the hospital’s simulator program, which includes 3-D models and other forms of simulation. “We’re trying to make surgeons more prepared to take care of these kids. The fact that they’ve seen the anatomy before is a complete game changer.”
Myalynn, at 16, was already familiar with brain surgery; she had a tumor removed three years ago. But since then, the teen from West Springfield has suffered violent seizures that could strike at any time. Sometimes, she had long stretches without a seizure. Other times, she endured four in a day.
Medication didn’t help. The seizures got longer. Her mother, of necessity, became a light sleeper.
“You can only do so much when you have a child like that,” said her mother, Celinez Jodoin. “You’ve got to protect them. My biggest job is to make sure she doesn’t tumble and hit her head and break anything.”
After talking to doctors, Myalynn and her mother realized another surgery was the best option. Myalynn’s brain had become a complicated tangle of healthy tissue, tumor, and scar tissue from her previous operation. Doctors at Children’s request 3-D models when they’re confronted with particularly complex cases, so Madsen, Myalynn’s neurosurgeon, ordered a model of her brain.
Many hospitals contract with outside vendors to produce 3-D models, but at Children’s everything is done in-house. Children’s began its program with 20 printed models in 2013 and now prints dozens of models every month for neurosurgeons, plastic surgeons, orthopedic surgeons, and others.
Engineers use different materials and dyes to make the most realistic copy of a patient’s anatomy. The models, made of acrylic resin, take several hours to print.
Using data from Myalynn’s MRI scans, the printer was programmed to create a life-size replica of her brain that Madsen could hold in his hands. It contained the unique abnormalities of her brain tissue, the intermingling of her blood vessels. Madsen conducted a mock operation: Masked and gloved in an operating room, scalpel in hand and microscope overhead, he carefully made his cuts into the model brain.
The practice run gave him a blueprint for what to do when Myalynn’s real brain was in front of him a few days later. It also helped him explain the operation to Myalynn and her mother.
“He made sure he pinpointed every detail of what he was going to do,” Jodoin said. “I absolutely think it can bring comfort to a family to know the doctor is very serious about this, that he’s tested on a model.”
On the day of the surgery, Madsen peeled back the skin on the side of Myalynn’s head, drilled through the bone, and used his instruments to gently probe the brain, hunting for the bad tissue that needed to come out. The 3-D model was in the operating room with him. He glanced at it a few times to remind himself of the meticulous plan of attack he had practiced earlier.
At the end of the day, after five hours of surgery and many more hours scanning and measuring his progress, Madsen had removed a couple of ounces from Myalynn’s brain and was confident the girl would be healthier as a result.
Other hospitals in Boston and around the world have turned to 3-D printers, not only for surgical models but also to create customized prosthetics or implants for patients.
Brigham and Women’s Hospital uses models to prepare for the most complex facial surgeries, including transplants. Beth Israel Deaconess Medical Center is experimenting with 3-D-printer-made stents that keep airways open for people who have trouble breathing. Tufts Medical Center is making prosthetic ears for babies born without them.
Minneapolis-based Stratasys Ltd., one of the world’s top sellers of 3-D printers and maker of the printer used by Children’s, said its sales to the medical industry grew 25 percent last year, and they’re projected to grow even faster in the year ahead.
3-D printing is no longer just a fad in medicine, says Scott Rader, general manager of medical solutions for Stratasys: “We have now seen physicians who are really thinking about how to implement excellence in patient care using 3-D printing.”
Children’s Hospital is planning to launch a study to measure the benefits of using 3-D printers. But the anecdotal response from surgeons so far indicates that models are saving time in the operating room. Complex surgeries can run tens of thousands of dollars, so shaving even minutes from a long operation can cut costs. Faster operations could also allow hospitals to accommodate more surgeries per day.
Models can save time by limiting surgeon guesswork. Dr. John Meara, who repairs face and skull defects in children, said he has changed operating plans many times based on something — generally a piece of bone — he saw or felt in a model.
“In the past, sometimes you had to make many incisions in the operating room,” said Meara, plastic surgeon-in-chief at Children’s. “Now I’m making those decisions on a model ahead of time.”
Hospitals now cover the costs of the models, which at Children’s range from about $50 to $2,000 depending on their size and complexity. But the widespread adoption of 3-D models hinges on whether insurance companies will deem them sufficiently vital, medically, to reimburse.
While Children’s is encouraging doctors to consult models even for some routine surgeries, many physicians believe the technology should be used selectively.
At Tufts Medical Center’s Floating Hospital for Children, Dr. Andrew R. Scott, an ear, nose, and throat surgeon who operates on infants, said he orders models only for special and complex cases because he is concerned about exposing patients to unnecessary radiation from CT scans, which are required to produce 3-D models of bones.
“Like a lot of technologies, it has the risk of being overdone,” Scott said. “It’ll be interesting to see where this evens out in time.”
A few days after Myalynn’s surgery, she was back home in West Springfield, resting in sweatpants. The swelling of her face had come down. A blue scarf wrapped around her head covered her scar.
Myalynn has not had a seizure since the surgery, but it is still too early to know whether the procedure worked. She and her family are hoping she is rid of the illness that would otherwise keep her from spending the night at a friend’s house, getting her driver’s license, and, in a couple of years, going off to college.
“If this becomes a success for her,” her mother said, “it’ll be a brand new day for us.”