Fetal Care Center Wins Innovation Research Award with New Fetal ETV Procedure
A new procedure to address fetal hydrocephalus is on the horizon. Researchers at Cincinnati Children’s recently tested an updated version of endoscopic third ventriculostomy (ETV) during the intrauterine period that has demonstrated outstanding results.
Led by Jose L. Peiro, MD, PhD, director of endoscopic fetal surgery in the Fetal Care Center, a team of Cincinnati Children’s researchers received the Award for Best Innovation during the June International Pediatric Endosurgery Group meeting in Miami. They were recognized for their achievements in testing prenatal ETV in fetal lambs.
“This is the first time this procedure has been conducted this way in any model,” Peiro says. “While other researchers have inserted a camera into the fetal lamb brain before, they did not complete the ventriculostomy. This is the innovative part, and it will give us the opportunity to study the effects of the surgery and increase our skills before implementing this procedure in humans."
Current Fetal Hydrocephalus Treatment
Fetal hydrocephalus occurs in roughly one out of every 2,000 births. Fetal ultrasound can reveal whether an unborn child has a build-up of cerebrospinal fluid (CSF) in the cerebral ventricles. If accumulation is detected, fetal magnetic resonance imaging (MRI) can help to determine the severity of the condition.
Currently, ventricular derivation with shunt-devices or ETV are the only surgical intervention available to treat congenital hydrocephalus. However, it can only be done after birth. Consequently, while it helps manage the condition, it cannot fully address it.
"During fetal development, this cerebral compression causes lots of problems, including irreversible brain damage,” Peiro says. “During the first days of life, these babies need a shunt that can remove the extra fluid and provide decompression. But, by then, it’s too late. The brain has already been harmed.” As a result, he says, these children have neurodevelopmental and cognitive problems that will require life-long care. In some cases, fetal hydrocephalus can be fatal.
Fetal ETV in the Fetal Lamb Model
Attempts to develop an in-utero fetal intervention for hydrocephalus have been ongoing for nearly 40 years, Peiro says. Neurosurgeons have tried placing ventricular amniotic shunts to relieve pressure on the brain, but this strategy has been unsuccessful.
“Many times, these little tubes get dislodged, blocked, or the amniotic fluid backflows into the ventricle,” he says. “That’s a bad thing.”
Other groups have tried to re-engineer shunts to make them more effective. However, Peiro and his group wanted to approach this problem in a different way.
“We wanted to be more original and look for a solution that fixes the problem without leaving a device in the brain,” he says. “Instead, we turned to the best animal model for fetal therapy—the fetal lamb.”
Peiro’s team injected several fetal lambs with intracisternal BioGlue to induce fetal hydrocephalus. Three weeks later, they confirmed the condition via ultrasound. After placing the pregnant sheep under general anesthesia, they performed fetal ETV on each lamb.
Although fetal lambs have longer skulls, the team successfully performed an intraventricular neuroendoscopy getting a good view of each lamb’s brain. Using an endoscope, they located and perforated the tuber cinereum region of the third ventricle, allowing the accumulated CSF to escape.
“Our results demonstrate that the ventricles do reduce in pressure and decrease in size,” Peiro says. “These outcomes show we were successful and that it’s feasible to do this procedure.”
The Next Step for Fetal ETV
Although their study shows fetal ETV can effectively alleviate fetal hydrocephalus, there’s still a long road ahead. The next step is to examine the molecular and cellular changes that occur in brains impacted by this condition.
“We will be working with microscopes to examine the development and neural progenitor cells in the brain that are improved by this technique,” he says. “That will also allow us to study the long-term effects on these animals postnatally.”
Ultimately, Peiro says, his team plans to pursue Institutional Review Board approval for a clinical trial that will prove fetal ETV is feasible and safe in humans.
“Our goal is that one day moms with babies who have this condition can contact and come to us for this procedure,” he says. “We’ll be very happy to add another procedure to the fetal surgery arsenal that we currently offer for other conditions.”
