Managing congenital anomalies with fetoscopic therapy

March 20, 2020

Mayo Clinic is pioneering advances in fetal surgery, allowing for earlier intervention to manage congenital anomalies such as congenital diaphragmatic hernia, bladder outlet obstructions, spina bifida, twin-to-twin transfusion syndrome and many other conditions. Typically these problems, which carry significant risk of mortality and disability, have been treated after birth.

Rodrigo Ruano, M.D., Ph.D., with Obstetrics and Gynecology at Mayo Clinic in Rochester, Minnesota, and a multidisciplinary team of experts are working to develop surgical methods to reverse these conditions in utero. In 2018, their report in Mayo Clinic Proceedings described two successful cases of prenatal management of severe congenital diaphragmatic hernia with fetal surgery.

In this Q&A, Dr. Ruano discusses advances in fetal surgery, specifically regarding fetal endoscopic tracheal occlusion for congenital diaphragmatic hernia.

Fetal surgeries require a multidisciplinary team. What does that team look like at Mayo Clinic?

This multidisciplinary approach is the key point at Mayo Clinic — it is what really makes our program strong. Different physicians from different specialties come together to provide the best possible care. To execute these procedures, an integrative team is involved; it includes specialists in fetal regenerative medicine and surgery, pediatric anesthesiology, pediatric surgery, pediatric otolaryngology, neonatology, obstetric anesthesiology, and maternal-fetal medicine. As a major tertiary medical center, Mayo Clinic Children's Center has the expertise to manage patients with complex conditions.

What is fetal endoscopic tracheal occlusion?

Fetal endoscopic tracheal occlusion (FETO) is a procedure that is offered for babies with severe congenital diaphragmatic hernia before they are born. Its objective is to promote lung growth. The procedure is performed with ultrasound-guided uterine access and fetoscopic deployment of a detachable tracheal balloon at 26 to 30 weeks of gestation. The balloon is intended to remain in place until about 34 weeks of gestation, when it is removed through a fetoscopic procedure. The treatment optimizes lung parenchymal growth, improving pulmonary hypoplasia and vascular remodeling.

As reported in 2018, a Mayo Clinic multidisciplinary team provided prenatal regenerative medicine service for two fetuses, resulting in fetal lung growth. Why is regenerative medicine proving to be safe and feasible?

At Mayo Clinic, we care for the whole patient. For infants, this process begins before birth. As described in our report, we cared for two fetuses with congenital diaphragmatic hernia. We're committed to advancing this area. Three pieces are essential to success:

  • An integrated, multidisciplinary team that addresses the needs of both the mother and the fetus
  • A well-coordinated group, organized by a fetal regenerative specialist
  • An advanced medical center that has necessary resources, infrastructure and expertise

Fetal endoscopic tracheal occlusion promotes lung growth ― a clear clinical example of in utero regenerative medicine.

What were the perinatal outcomes for the maternal patients and their babies mentioned in your report?

Our first patient underwent spontaneous labor and delivered a healthy baby girl at 38.6 weeks, 10 weeks after tracheal balloon placement and three weeks after balloon removal. After the birth, both the mother and baby were in stable condition. The baby had diaphragmatic repair soon after birth and now she is at home with normal life.

Regarding the second patient, the mother presented with preterm prelabor rupture of membranes at 32.3 weeks, four weeks after tracheal balloon placement. After an emergent removal of the balloon by ex utero intrapartum treatment (EXIT) procedure, a modified cesarean delivery was performed. A baby boy was born and transferred to the neonatal intensive care unit, but had the diaphragm repaired soon after birth and he is at home doing very well in room-air condition.

How are the infants faring today?

Lung growth essentially doubled in one fetus and increased by a third in the other. After birth, when the infants left the hospital, the first, the baby girl, was breathing normally and the second, the baby boy, required minimal oxygen support. But now, both babies are breathing normally.

The baby girl was discharged home on room air 33 days after delivery; the baby boy was discharged 41 days after delivery. Both infants are feeding, growing and gaining weight well. Neither of them have any respiratory symptoms nor are there developmental concerns.

What do these outcomes mean for fetal surgery in the future?

Our results provide a blueprint for other fetal regenerative services that focus on improving prenatal care. These services address anomalies beyond congenital diaphragmatic hernia to include spina bifida, lower urinary tract obstruction, twin-to-twin transfusion syndrome, fetal tumors and severe cardiac anomalies. Our team has recently started to offer fetoscopic repair of spina bifida with promising outcomes for mothers and babies.

For more information

Ruano R, et al. Fetoscopic therapy for severe pulmonary hypoplasia in congenital diaphragmatic hernia: A first in prenatal regenerative medicine at Mayo Clinic. Mayo Clinic Proceedings. 2018;83:693.