For the first time, surgery has fixed an abnormal blood vessel in a fetus’s brain. The baby – who has a rare condition called vein of Galen malformation – was born without complications, indicating the procedure can safely treat infants.
The vein of Galen malformation forms before birth when arteries in the brain connect back to the central vein of the limb. This dilates this vein and allows more blood to flow through, putting pressure on the heart and lungs and depriving the brain of oxygen. Babies with this condition usually develop heart failure and stroke-like symptoms within days of birth.
“There are too many patients we can’t help even with the best standard of care,” says Darren Orbach at Boston Children’s Hospital in Massachusetts. Before babies with this condition are born, the placenta helps relieve some of the pressure. Once they are born, it may be too late to perform surgery. “They unfortunately die despite our best efforts, or they are left with severe brain injuries,” he says.
Orbach and colleagues performed surgery to correct the malformation in a fetus at 34 weeks and 2 days gestation. MRI scans revealed that the central vein was more than 14 millimeters in diameter. “When the vein width is 8 millimeters or more, we know with 90 percent certainty that the baby is going to be very sick after birth,” Orbach says. “It was one of the more aggressive deformities we’ve seen.”
The woman carrying the fetus was given spinal anesthesia prior to surgery and the fetus was also given an injectable anesthetic to prevent it from moving during the procedure. After this a needle was inserted into the uterus. Ultrasound imaging helped target it to the back of the fetal head, where the malformation was located.
The surgeons gently push the tip of the needle into the vein. A catheter placed through the needle was then used to insert special metal coils into the extra space created by the deformity. These coils reduce the amount of blood flowing through the vein. The surgery lasted less than 2 hours.
An ultrasound a day later showed a 43 percent decrease in the amount of blood pumped by the fetal heart. MRIs taken before and after surgery also showed that the vein had shrunk to about 5 millimeters in diameter. The baby was born two days later prematurely without any complications. He did not require cardiac medications or additional surgery.
“It was remarkable because these kids are usually so dramatically ill,” says Orbach. They say the baby, who is now 7 weeks old, still appears to be healthy.
This surgery is a promising approach to preventing brain injury and death in infants with vein of Galen malformations, which can’t be treated after birth, says courtney wusthoff at Stanford University in California. “The downside is that any time you’re doing a fetal procedure, there’s a risk of complications and, in particular, preterm birth,” she says.
“It’s obviously very exciting to have this result in the first patient, but it’s really the first patient. We have to do the science and demonstrate that it works on patients,” says Orbach, who will study with an additional 19 participants. I am planning to have surgery.