In a first, a potentially fatal rare blood vessel disorder is treated in the womb

For Darren Orbach, a pediatric neuroradiologist at Boston Children’s Hospital, the first-of-its-kind procedure to fix a potentially deadly vascular malformation in the brain of a fetus was an “exhilarating” experience, despite the sobering potential consequences.

For the expectant parents, it was an exercise in hope.

Orbach recalls the couple had read all about the vein of Galen malformation of the baby they were expecting. They had watched all the hospital videos. They had spoken to parents in an advocacy group for this rare disorder — from those of infants with vein of Galen malformation who didn’t survive to the parents of those who survived and grew up to be healthy adolescents.


“And so they were able to really see the full possible range and understand what they would be facing,” Orbach said.

The vein of Galen malformation occurs when misshapen arteries in the brain connect directly to veins instead of capillaries. As a result, the flow of blood in the brain is so intense it often leads to heart failure, severe brain injury, or even death soon after birth.


Researchers — a multidisciplinary team at Boston Children’s Hospital and Brigham and Women’s Hospital focused on fetal cardiac procedures — collaborated to design a procedure for high-risk infants with this brain problem. After getting approval from both hospitals’ review boards, members of the team also needed approval from the Food and Drug Administration, since they were using medical devices “definitely not made for fetal brain surgery,” Orbach said.

There’s no animal model for this kind of condition. So a specialized group at Children’s Hospital built a simulated fetal phantom brain so researchers could practice the procedure. They answered their own questions as they went: Were they able to see everything under ultrasound? Were they able to see their tools? Could they successfully complete the embolization, a procedure that uses particles like soft platinum coils to close a blood vessel and reduce the abnormal blood flow to the vein of Galen?

Then came the long wait. The vein of Galen malformation is so rare, researchers had to find the right subject — a fetus with a brain in good enough shape at the time of diagnosis but still at very high risk for having a bad outcome after birth if doctors just did the standard treatment. The idea was to intervene before there were any brain injuries.

Orbach spread the word about the research project during talks to scientific and medical groups in late 2020. He and his colleagues also reached out to a patient advocacy support group for parents. That’s ultimately how they found the couple willing to do the surgery.

On March 15, researchers performed the procedure on the fetus at 34 weeks and 2 days gestational age. The very next day, a fetal echocardiography showed a huge improvement in the heart function.

A scientific paper describing the procedure was published in the journal Stroke on Thursday.

Since her birth, the infant hasn’t required medication to treat heart failure, or postnatal surgery to treat the malformation, as is often the case, researchers reported. Nothing concerning has turned up over multiple echocardiograms, brain MRIs, and neurological exams.

“Even right in the moment, to just succeed technically and put those coils out … was exciting,” Orbach said. “We were able to see right away on the ultrasound that the flow came way down. That was a great, great first step.”

Orbach and colleagues watched her in the neonatal intensive care unit (NICU) day after day.

“That’s when it really started hitting home that this baby was just doing great,” Orbach said. “Because all of us who care for these kids see how very sick these babies are, in the NICU, for weeks and weeks or months. And just to see her look fine, really on no medication and not in a breathing tube or anything like that, that was really fantastic.”

While Gary Duckwiler, an interventional neuroradiologist at the David Geffen School of Medicine at UCLA, is impressed by these early results, he remains cautious. With embolization with coils, he explained, “you’re going through the skull into this very high-flow vein in the brain, and precise entry is critical” to avoid complications. “Is there a potential for bleeding in the brain from either the access or the treatment? … But that risk has to be weighed against the potential fatality and neurologic injury associated with this poor prognosis disease.”

Orbach acknowledges this is just the first of 20 patients in a clinical trial to evaluate the safety and effectiveness of the procedure. But he’s optimistic. He says it took courage for the first family to “jump into the deep water” on this unique procedure, but that it hopefully requires less courage now that there’s a good outcome.

“It’s been a long haul to get to the right first patient,” he said. “I’m hoping that as word gets out of this outcome, families will be ready to try this.”

Source: STAT