Enhancing fetal spina bifida repair: do paraspinal myofascial flaps and acellular dermal patches improve postnatal outcomes? A retrospective cohort review

OBJECTIVE: The primary objective of this study was to assess whether incorporating paraspinal myofascial flaps and/or an acellular dermal matrix (ADM) patch during open fetal surgery for open spina bifida (OSB) impacts the need for CSF diversion by 1 year of age. A secondary objective was to determine whether these interventions affect pregnancy outcomes. METHODS: The authors retrospectively reviewed all fetuses undergoing open fetal OSB repair at their center from June 2017 through April 2024. Factors associated with CSF diversion surgery at 1 year of age were collected and included lesion type, lesion level, lateral ventricle size, and gestational age (GA) at surgery. Pregnancy outcomes assessed were GA at delivery and the incidence of prelabor premature rupture of membranes (PPROM). Univariate and multivariate logistic regression were used to evaluate factors associated with postnatal CSF diversion at 12 months. Chi-square tests and 1-way ANOVA were used for group comparisons. RESULTS: Of 57 fetuses treated with surgery, 4 were excluded (due to failed repair, early delivery, neonatal death, or loss to follow-up), leaving 53 neonates for analysis. In univariate analysis, the use of myofascial flaps (OR 0.14, 95% CI 0.01-0.81) and ADM patches (OR 0.26, 95% CI 0.05-0.95) was associated with reduced odds of CSF diversion. In multivariate analysis, ADM patch use remained significantly associated with a reduced need for diversion (aOR 0.24, 95% CI 0.01-0.70), while myofascial flap use showed a trend toward benefit (aOR 0.34, 95% CI 0.01-1.03). PPROM rates were not significantly different between the groups: 32.1% without either intervention, 33.3% with myofascial flap alone, 27.3% with ADM alone, and 16.7% with both (p = 0.85). The mean GA at delivery was also similar: 35.1 ± 1.8 weeks (no ADM patch/flap), 35.4 ± 1.5 weeks (myofascial flap), 35.0 ± 3.2 weeks (ADM patch), and 35.3 ± 2.5 weeks (both) (p = 0.98). CONCLUSIONS: Use of an ADM patch during fetal OSB repair was associated with a lower likelihood of requiring CSF diversion at 1 year. Paraspinal myofascial flaps showed a favorable trend toward similar benefit. Neither intervention increased the risk of PPROM or preterm birth, supporting their safety as surgical adjuncts.