New insights in cerebral findings associated with fetal myelomeningocele: a retrospective cohort study in a single tertiary centre

Objective To investigate cerebral anomalies other than Chiari type 2 malformation in fetuses with myelomeningocele (MMC). Design A retrospective cohort study in a single tertiary centre. Setting A review of associated cerebral anomalies in cases with prenatal diagnosis of myelomeningocele. Population Seventy cases of fetal myelomeningocele. Methods Ultrasound and MRI images were blindly reviewed. Postnatal imaging and results of the postmortem results were also reviewed. The association between cerebral anomalies and the following ultrasound findings was measured: level of the defect, ventriculomegaly, microcephaly and fetal talipes. Main outcome measures A microcephaly was observed in 32/70 cases (46%) and a ventriculomegaly was observed in 39/70 cases (56%). Other cerebral anomalies were diagnosed in 47/70 (67%). Results Other cerebral anomalies were represented by 42/70 cases with abnormal CC (60%), 8/70 cases with perinodular heterotopia (PNH; 11%), 2/70 cases with abnormal gyration (3%). MRI performed only in fetal surgery cases confirmed the ulltrasound findings in all cases and provided additional findings in two cases (PNH). Risk ratios of fetal cerebral anomalies associated with MMC did not reach significance for microcephaly, ventriculomegaly, talipes or the level of the defect There was an overall good correlation between pre- and postnatal findings with a Kappa value of 0.79 [95% CI 0.57-1] and 82% agreement. Conclusion Fetal brain anomalies other than Chiari type 2 malformation are frequently observed in fetuses with myelomeningocele, predominantly represented by CC anomalies. Whether these associated cerebral anomalies have an impact on selecting cases eligible for fetal surgery needs further evaluation. Tweetable abstract Fetal cerebral anomalies other than Chiari type 2 malformation, microcephaly, and ventriculomegaly may be associated with MMC in up to 67% of the cases.

Automated summary

The study found that besides Chiari type 2 malformation, other cerebral anomalies are frequently observed in fetuses with myelomeningocele, with the most common being abnormalities of the corpus callosum. Whether these associated cerebral anomalies affect the selection of cases eligible for fetal surgery requires further evaluation.