Acalvaria

A rare congenital malformation characterized by the absence of calvarial bones, dura mater and associated muscles while skull base, facial bones and brain structures are normal. Central nervous system is usually unaffected, however some neuropathological abnormalities such as holoprosencephaly, hydrocephalus, micropolygyria and gyration anomalies can be present. Prenatal diagnosis by ultrasonography is usually confirmed by magnetic resonance imaging as it can be confused with anencephaly or ence