In the time since initial results of the Management of Myelomeningocele Study (MOMS) were announced in December 2010, fetal myelomeningocele (fMMC) repair has become an accepted standard of care option for prenatally diagnosed spina bifida in appropriately selected fetal surgery candidates, and optimal care guidelines have been developed.
To determine the reproducibility of results outside the setting of a rigorous trial, the Center for Fetal Diagnosis and Treatment at The Children’s Hospital of Philadelphia recently reviewed outcomes for fMMC repair since the MOMS results were reported, from referral and evaluation through surgery, delivery and neonatal discharge.
From Jan. 1, 2011, through March 7, 2014, 587 women were referred to our center for an indication of fMMC. Of these, 348 presented for prenatal evaluation at CHOP consistent with the protocol used in the MOMS trial, and 29 percent (100) of those women were candidates and were taken to the operating room for fMMC repair.
Perioperative care and postoperative follow-up were consistent with the MOMS trial protocol. However, if patients remained stable without complication, and their referring physicians were willing to care for them, patients returned to their home institution for delivery as determined on a case-by-case basis, which is an alteration from the MOMS trial.
A closer look at our findings
Our findings (which include only immediate neonatal outcomes) show that our experience with fMMC at CHOP beginning in 2011 is comparable to the MOMS trial results published in the New England Journal of Medicine, and we have seen improvements in many areas. Complications included membrane separation (22.9 percent), preterm premature rupture of membranes (32.3 percent), and preterm labor (37.5 percent). Average gestational age (GA) at evaluation, fMMC repair and delivery were 21.9 weeks, 23.3 weeks and 34.3 weeks, respectively, and 54.2 percent delivered > 35 weeks. The perinatal loss rate was 6.1 percent (two IUFD and four neonatal demises).
For 90.8 percent of women, delivery occurred in our Garbose Family Special Delivery Unit, the world’s first birth facility specifically designed for women carrying babies with prenatally diagnosed birth defects; of those, 3.4 percent received a transfusion at the time of delivery. There was no evidence of hindbrain herniation on MRI in 71.1 percent of neonates. Two neonates received ventriculoperitoneal shunts prior to discharge, and dehiscence of the fetal repair was noted in three neonates. In comparison to prenatal
anatomic lesion level by ultrasound, we saw an improvement in functional motor level by at least one level in 55 percent of neonates.
The perinatal loss rate of 6.1 percent in our series was higher than that of the prenatal repair group in the MOMS trial of 3 percent. We saw a higher rate of respiratory distress syndrome (51.8 percent vs. 21 percent) and apnea (57.8 percent vs. 36 percent) in our group due to broader inclusion criteria for these diagnoses. This has prompted our team to create a clinical care pathway for these neonates to monitor them closely for apnea.
Based on this data, we believe that fMMC repair outside of the MOMS trial at an experienced program will have similar outcomes. We will continue to follow patients to determine the rates of shunt placement and hindbrain herniation at 12 months of age, and to determine how longer-term functional motor outcomes correlate with the neonatal assessment.
With lessons learned and modifications in perioperative technique, it is likely that we can improve on these outcomes. We will continue to collaborate with centers that are performing fMMC repair to track results long term and promote further research to optimize safety and outcomes.
See a detailed report of fetal MMC repair outcomes at CHOP »
Moldenhauer JS, Soni S, Rintoul NE, Spinner SS, Khalek N, Martinez-Poyer J, Flake AW, Hedrick HL, Peranteau WH, Rendon N, Koh J, Howell LJ, Heuer GG, Sutton LN, Johnson MP, Adzick NS. Fetal Myelomeningocele Repair: The Post-MOMS Experience at the Children’s Hospital of Philadelphia. Fetal Diagn Ther. 2014 Aug 15. [Epub ahead of print].
More on prenatal surgery for MMC
Read more articles from this issue of In Utero Insights, where we share findings and best practices gleaned from — and since — the MOMS trial, including: