Figure 5From: A unifying hypothesis for hydrocephalus, Chiari malformation, syringomyelia, anencephaly and spina bifidaHypothetical graph depicting the relation between fetal lateral ventricle size and intracranial pressure and the effect of hindbrain impaction on ventricle size. Hindbrain impaction is caused by a pressure gradient across the foramen magnum. A relatively small intracranial pressure gradient will cause the lateral ventricles to empty. Progressive increase in cerebral pressure will then cause the ventricles to enlarge.Back to article page