Report on 100 Prenatal Surgeries for Spina Bifida Support it as New Standard of Care

Reporting on 100 recent cases of fetal surgery for spina bifida, specialists from The Children’s Hospital of Philadelphia achieved results similar to those in a landmark clinical trial that established a new standard of care for prenatal repair of this birth defect.

The single-center study from the Center for Fetal Diagnosis and Treatment at CHOP represents the largest series reported since 2011 when the National Institutes of Health-sponsored Management of Myelomeningocele Study (MOMS) published its results in the New England Journal of Medicine.

Three years ago, the MOMS showed that fetal surgery led to decreased rates of shunting, which involves implanting a tube to drain excess fluid from the brain, at 12 months of age. Fetal surgery also reversed a life-threatening condition called Arnold Chiari 2 malformation, otherwise known as hindbrain herniation, and improved the children’s outcomes, including their ability to walk at 30 months of age.

“The MOMS trial presented very encouraging results and helped experts develop guidelines for optimal care, but there were questions about whether the benefits of this procedure could be reproduced outside the setting of a rigorous trial,” said Julie S. Moldenhauer, MD, a maternal-fetal medicine specialist at CHOP and lead author of the current paper in the journal Fetal Diagnosis and Therapy. “This study shows that an experienced program can achieve comparable results, and that we can modify our techniques to improve on the trial outcomes.”

CHOP’s center was one of the three fetal surgery programs that participated in the randomized MOMS trial, and has been performing fetal myelomeningocele (fMMC) repairs since 1998. In total, CHOP has performed more than 1,175 fetal surgeries for a range of birth defects, the largest number of any hospital in the world.

The current study draws on a cohort from all patients referred to CHOP for potential fMMC repair between January 2011 and March 2014. Of 587 total referrals, the program designated 139 to be candidates for the fetal surgery, and 100 mothers completed the surgery.

The current cohort had a decreased incidence of preterm premature rupture of membranes (PPROM) compared to the MOMS group; average operative times were significantly shorter; there were decreases in the incidence of pulmonary edema and the transfusion rate at the time of cesarean delivery. Also, early neonatal MRIs showed that 71 percent of the infants had no evidence of hindbrain herniation, in which part of the cerebellum (hindbrain) protrudes through the opening in the base of the skull into the spinal canal and obstructs the flow of cerebrospinal fluid, leading to a progressive hydrocephalus.

In addition, when compared to prenatal ultrasound evaluations of the anatomic level of the myelomeningocele, 55 percent of the newborns in the study had improved functional motor level, but the authors added that follow-up research will be needed to determine if this benefit persists in longer-term outcome studies.