Chronic Decerebrate State in Infancy: Neurologic Observations in Long Surviving Cases of Hydranencephaly

THE TERM hydranencephaly designates the condition in which large portions of the cerebral hemispheres have been reduced to membranous sacs within a cranium of relatively normal size. It may be suspected in the newborn by cranial transillumination, which generally indicates a cerebral thickness of less than 1 cm.^1,2

Although this finding implies that such infants have varying levels of decerebration or decortication in a state sometimes permitting long survival, little attention has been paid to the clinical-physiologic features of hydranencephaly and related disorders with severe bilateral cerebral destruction or malformation. Despite many studies of the behavior of the normal newborn^3-9 and also of the variable sequences of changes in common spastic diplegia^10-12 little can be found concerning the neuroanatomic basis of such common neonatal activity as the Moro and the stepping reflexes. Moreover there are discrepancies between these studies and those in the experimental neurophysiologic literature on