Prenatally Diagnosed Holoprosencephaly: Review of the Literature and Practical Recommendations for Pediatric Neurologists

Holoprosencephaly (HPE) is one of the most common malformations in embryonic development. HPE represents a continuum spectrum that involves the midline cleavage of forebrain structures. Facial malformations of varying degrees of severity are also observed. It is probable that HPE results from a combination of genetic mutations and environmental influences during the initial weeks of pregnancy. Some patients with HPE experience early death, whereas others go on to experience neurodevelopmental impairment. Accurate fetal imaging can facilitate diagnosis and prenatal counseling, although more subtle brain abnormalities can be difficult to diagnose prenatally. Fetal counseling can be complex, given that the etiopathogenesis remains unclear and variable penetrance is prevalent in inherited genetic mutations. The aim of this narrative review is to examine the literature on HPE and to offer recommendations for pediatric neurologists for fetal counseling and postnatal care.