Postnatal in-vivo MRI findings in anencephaly.

We report on the MRI findings of an anencephalic infant who survived 10 weeks postnatally. MRI showed absence of the cranial vault, all supratentorial structures, and the cerebellum. A brainstem primordium without pontine prominence was present. The brainstem was surrounded by the area cerebrovasculosa. The absence of a pontine prominence in an anencephalic infant without cerebellar tissue supports the hypothesis that absent pontine prominence is found in children with a prenatal loss of cerebellar tissue.