The cranial base in anencephaly and microcephaly studied histologically.

A histological microradiographical analysis was carried out on the cranial base removed at autopsy from three infants--two with microcephalia, one with anencephalia. The histological findings were compared with those from normal individuals of the same age. It was shown that a reduced size of the brain was accompanied by a change in the remodeling pattern of the internal as well as the external surface of the cranial base, leading to a flattening of the cranial base. The findings further suggest that the development of the brain influences the ossification of the chondrocranium.