Dr. John Meara had a challenge in front of him. His patient, 4-month-old Bentley Yoder, needed to have part of his brain put back into his cranium.
The bones of his skull hadn't fully formed, and his brain was pushed through the bone, forming an eggplant-sized mass above his head. Meara, of Boston Children's Hospital, had a few ideas about way to approach the surgery, but he'd only get one shot at it in the operating room.
If only, he thought, there was a way to practice the procedure ahead of time.
As it happened, he was able to do exactly that before Bentley's surgery thanks to a 3D printing program Boston Children's Hospital started in 2014.
The hospital employs engineers to run the 3D printers, which use MRI or CT scans to reconstruct a patient's face, limb or other body part. In Bentley's case, the hospital made a model of his brain and cranium, and Meara was able to cut into the spongy model to test different methods and to make sure there were no surprises, like abnormal blood vessels, when the baby went under the knife.
"When you print out this model, it's an amazing opportunity for me to actually look at the anatomy and look at the skull from different angles and actually hold it in my hand and spin it around," he said. "It's very critical for these kinds of cases. They're rare, and each one is a little different, so you have to make a treatment plan just for these patients."
Boston Children's Hospital's simulation department has long used the latest technology to give their doctors and surgeons an upper hand when dealing with complicated cases, said Dr. Sanjay Prabhu, co-director of the hospital's SIMPeds 3D Print Service.
The hospital is among a handful using 3D printing to aid surgeons, doctors and medical students. Cincinnati Children's Hospital and New York-Presbyterian Morgan Stanley Children's Hospital have also used 3D printed organs, such as hearts, made from their patients' CT or MRI scans to practice complex surgeries ahead of time.
"We're a small market, but for us every child is important," Prabhu said.
The move to 3D printing at Boston Children's Hospital started when the simulation department tried to create a model of a mandible that was better than the outsourced molds they would purchase from companies, he said. Once word got around the hospital about the 3D-printed molds, orders started coming into the department for spines, skulls and full faces.
"The thing in the operating room is you want to be fast, you want to be safe, so having a model there helps," he said. "The communication improves if you have a tangible model."
"After the tumor's been treated, they take the tumor to the top of the roof and throw it down."
The models offer a few benefits. Doctors can use it to show to their operating room team so everyone is on the same page about what they're removing, what obstacles are in their way and the exact lay of the land, so to speak. And they can color-code different vessels and tumors.
It also helps the patients and their parents understand exactly what the doctors are about to do in the operating room. Meara said he sits parents down before a surgery and uses scans and the printed models to explain what steps he'll take to help their child. Often, the 2D scans leave them with more questions than answers, but they understand when they see the 3D model.
Patients have also found solace in hanging onto the surgical model until after their hospital stay is over, Prabhu said. Patients with cancer will often ask to have the 3D printed model of the tumor after surgery or chemotherapy.
"After the tumor's been treated, they take the tumor to the top of the roof and throw it down," he said.
3D printing means Meara can plan the entire surgery ahead of time, which makes them faster. Faster surgeries mean less bleeding, which can make a huge difference when caring for tiny patients. Even parts of the surgery that had to be done on-the-fly, like cutting screws that hold bones together to the right size, can also be done ahead of time.
"It certainly helps with comfort and the fact that you have a much better sense of anatomically of what you're doing," he said.
Practice can begin early — even before birth. In one case, doctors were trying to decide whether to operate on a fetus in-utero to fix a dangerous facial abnormality. By scanning the fetus's face, doctors were able to take a look at their patient before he'd had his first glimpse of the world.
The 3D printed model showed the baby would be able to be delivered safely without surgery, so doctors postponed the procedure, which had risks on its own. The child was delivered without an issue.
As for baby Bentley, he's a happy, healthy little 1-year-old, Meara said. He said the printed model helped make the surgery quick and relatively straight-forward, in what would have ordinarily been a procedure that kept him on his toes for 10 or more hours.
"He's doing fantastic," Meara said.
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