Open Fetal Microneurosurgery for Intrauterine Correction of Encephalocele: A Prospective 1-Year Follow-Up Study

We aim to describe the feasibility and outcomes of fetuses with occipital encephalocele treated with intrauterine repair by open microneurosurgery.

Between 2021 and 2025, a consecutive cohort of fetuses with occipital encephalocele referred to 2 fetal surgery centers in Nicaragua and Mexico were selected for intrauterine correction by open fetal microneurosurgery. Inclusion criteria were fetuses at less than 28 weeks with isolated occipital encephalocele, Chiari III malformation (obliteration of the cisterna magna with protrusion of cerebral tissue), and microcephaly. We report the procedure-related characteristics, perinatal and neurological outcomes (hydrocephalus, meningitis, seizures, cognitive delay, motor dysfunction, and visual impairment) within the first 12 months of age.

Twelve cases were evaluated during the study period but only 6 cases were selected for fetal intervention. Open fetal microneurosurgery was successfully performed in all cases at a median gestational age (GA) of 25+2 weeks+days, with a median surgical time of 93 min. Regression of Chiari and reversal of microcephaly was observed in 4/6 and 6/6 cases, respectively. The median GA at birth was 36+5 weeks+days. Preterm rupture of the membranes and preterm delivery was reported in 3/6 cases. No cases of perinatal death were reported. Within the first 12 months of age, none of the children developed meningitis, cognitive delay, or hydrocephalus requiring ventriculoperitoneal shunting. Motor dysfunction, seizures, and visual disorders were reported in 1/6, 1/6, and 3/6 cases, respectively.

In this small series of fetuses with occipital encephalocele, open fetal microneurosurgery was feasible and was associated with promising outcomes.