3D printing guides a tricky brain surgery

3D printingTwo and a half years ago, 15-year-old Adam Stedman had a seizure out of the blue.

“I heard a noise and went in and saw him in a full-blown tonic-clonic seizure,” says his mother, Amy.  Paramedics brought him to the hospital. Any further seizures could mean trouble, they told the Stedmans. “They said, basically, ‘you’re allowed one seizure in your life,’” Amy recalls.

A few months later, on an August evening around 10 p.m., Adam spoke with his girlfriend on the phone. She later told Amy, “Go check on him—he sounds kind of out of it.” That turned out to be a second seizure.

The third seizure, the worst yet, happened on Nov. 11. Adam had the day off from school, and his girlfriend was visiting. The family was eating dinner when the seizure started. It lasted nearly five minutes, and Adam was turning blue. Another seizure followed within weeks. The local hospital in Connecticut did an MRI, and the Stedmans received a call: “Can you come in before the office opens?”

Adam had an arteriovenous malformation, or AVM, a tangle of abnormally connected arteries and veins. Through a recommendation, the Stedmans met five days later with Dr. Edward Smith, a neurosurgeon in Boston Children’s Hospital’s Cerebrovascular Surgery and Interventions Center.

Because the AVM was in the visual processing area of his brain, Adam faced a risk of serious vision loss if the AVM wasn’t removed soon. It could bleed or burst at any time.

But the surgery itself posed a risk, Smith warned.

“They told us to be prepared for serious vision loss,” says Amy.

Dr. Darren Orbach, the neuroradiologist who imaged Adam’s brain, said it was hard to predict from the imaging whether his vision would be affected.

But Adam was ready to proceed. “It was right after my 15th birthday and I just wanted to get it out of my head and get on with my teenage life,” he says.

A dress rehearsal 

Smith decided he needed to rehearse the tricky procedure in advance.  “In AVMs, there’s a need to cut the blood vessels in a very specific sequence, like defusing a bomb,” he explains. “A lot of the vessels were deep, and we needed to get a sense of which were feeding the AVM and which were draining it. You want to turn the faucet off before you close the drain; if not, the sink overflows.”

That’s how Adam became one of the first patients to have his blood-vessel anatomy reproduced through 3D printing technology.  In January 2014, he had an arteriogram—a catheter procedure done under anesthesia that gathers detailed, live x-ray images of the AVM and the vessels feeding it. The imaging data were programmed into a computer and used to reconstruct a life-size 3D replica of Adam’s AVM.

3D printing makes for more efficient surgery

The surgery, performed two months later by Smith and Dr. Michael Scott, went off without complications. Smith was able to remove the AVM in just 2 ½ hours rather than the five he’d prepared the Stedmans for. “The model allowed me to go directly to the right pipes as quickly and efficiently as possible, because I’d practiced those steps ahead of time,” he says.

3D print
Adam’s AVM print

After three nights in the hospital, Adam went home. This past July, he had his one-year follow-up angiogram. “It was totally negative,” says Orbach. “No residual anything.”

Now 17 and in his senior year of high school, Adam has been tapering off his anti-seizure medications under the supervision of his neurologist in Connecticut. He does have a small blind spot in his vision, where the AVM was, forcing him to turn his head to see everything in front of him.

“It’s just a little dot, on the left side,” says Adam. “If I’m looking at something, I can’t see the thing right next to it. Sometimes I look over and say, oh, hey, I didn’t know that was there.”

“With therapy, you can learn to overcome a restriction of your visual field,” says Orbach. “Adam’s not acting as if he has any deficit.”

His parents had been bracing for much worse, and credit the 3D imaging for sparing Adam’s vision. Amy keeps a photo of his 3D-printed vessels on her phone. “I want to dip it in gold and wear it as a necklace,” she says.

Learn more about how Boston Children’s doctors use 3D printing.