Fetal surgery for myelomeningocele and the incidence of shunt-dependent hydrocephalus

Context Intrauterine closure of exposed spinal cord tissue prevents seconda ry neurologic injury in animals with a surgically created spinal defect; ho wever, whether in utero repair of myelomeningocele improves neurologic outc ome in infants with spina bifida is not known. Objective To determine whether intrauterine repair of myelomeningocele impr oves patient outcomes compared with standard care. Design Single-institution, nonrandomized observational study conducted betw een January 1990 and February 1999. Setting Tertiary care medical center. Participants A sample of 29 study patients with isolated fetal myelomeningo cele referred for intrauterine repair that was performed between 24 and 30 gestational weeks and 23 controls matched to cases for diagnosis, level of lesion, practice parameters, and calendar time. All infants were followed u p for a minimum of 6 months after delivery. Main Outcome Measures Requirement for ventriculoperitoneal shunt placement, obstetrical complications, gestational age at delivery, and birth weight f or study vs control subjects. Results The requirement for ventriculoperitoneal shunt placement for decomp ression of hydrocephalus was significantly decreased among study infants (5 9% vs 91%, P =.01). The median age at shunt placement was also older among study infants (50 vs 5 days; P =.006). This may be explained by the reduced incidence of hindbrain herniation among study infants (38% vs 95%; P<.001) , Following hysterotomy, study patients had an increased risk of oligohydra mnios (48% vs 4%; P =.001) and admission to the hospital for preterm uterin e contractions (50% vs 9%; P =.002). The estimated gestational age at deliv ery was earlier for study patients (33.2 vs 37.0 weeks; P<.001), and the bi rth weight of study neonates was less (2171 vs 3075 g; P<.001). Conclusions Our study suggests that intrauterine repair of myelomeningocele decreases the incidence of hindbrain herniation and shunt-dependent hydroc ephalus in infants with spina bifida, but increases the incidence of premat ure delivery.