Antenatal Diagnosis of Craniosynostosis

Prenatal diagnosis of craniosynostosis remains challenging in isolated single-suture forms. Abnormal skull shape, abnormal cephalic index, the brain shadowing sign, and ventriculomegaly are the main key features for detecting fetal craniosynostosis in 2D-US. Once craniosynostosis is suspected, patients should be referred to a fetal medicine unit in order to perform a second-level scan by an expert in fetal neurosonography to confirm the diagnosis and to assess the associated malformations. A 3D-US may be an optional additional tool to improve the exploration of the skull sutures and to help future parents visualize the malformation. MRI, as a complementary imaging modality, allows detection and better assessment of central nervous system malformations which may be associated with craniosynostosis. Distinguishing between isolated and syndromic craniosynostosis is crucial during the prenatal period for appropriate counseling and scrutinizing for fetal limbs and facial anomalies is useful. Once the diagnosis of craniosynostosis is made, fetal chromosomal microarray and molecular analysis should be recommended.