ABSTRACT
Congenital malformations of the brain and spinal cord represent one of the most important problems facing clinicians, neuroscientists, and public health officials. Encouraging progress has been made, but the etiologies of most congenital malformations of the brain and spinal cord remain unknown, and the goal of preventing most congenital nervous system malformations has not been realized. The epidemiologic study of congenital malformations differs from the epidemiologic study of other chronic diseases. Individual malformations tend to be timing specific rather than etiologically specific. Anencephalus is due to a failure of the rostral neural tube closure. Anencephaly commonly involves the forebrain and variable amounts of the upper brain stem. Myelomeningocele results from a partial failure of caudal neural tube closure during primary neurulation. Neural tube defect is the generic term used to describe a malformation resulting from the nonclosure of the neural tube.
