Exencephaly is a lethal congenital fetal brain developmental anomaly (neural tube defect).
- maternal serum alpha feto protein (MSAFP) levels are highly elevated (x 2.5 MoM)
Imaging features have some overlap with that of anencephaly except that there is some brain tissue presence:
- cranial vault is absent or poorly formed, cephalad to orbits
- the nasal bone may be absent in most cases
- brain tissue is herniating or dangling in amniotic fluid
- brain tissue may be attached to the amniotic membrane
Treatment and prognosis
Exencephaly is a precursor to anencephaly, and essentially a lethal condition. Advise and counselling for abortion is to be given to the parents.
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