Developmental Neuropathology

The present text was envisioned as a supplement to eXlstmg texts on human neuropathology, covering only those aspects of pediatric neuropathol- ogy which pertain to and are peculiar of the immature nervous system. No coverage-or only brief comment-is given to diseases commonly found in adults which may, on occasion, occur in childhood or infancy as well. The subject matter is divided into three main categories: 1. The 'acquired' lesions dating to the fetal, perinatal or early postnatal periods, 2. the malformations, and 3. the heritable metabolic defects. The first 6 chapters (2-7) are reserved to the lesions most intimately linked to the circumstances of birth. There is some inherent ambiguity in distinguishing between 'acquired' lesions and malformations, as, indeed, no sharp distinction can be made between one and the other. Many malformations result from diseases acquired during fetal life and their peculiarity resides in the fact that the organ becomes affected before its development terminates and in such a way that its subsequent development becomes deranged or partly abrogated. A variety of causes acting at the same developmental period or over a common pathogenetic mechanism may produce the same type of derangement, including chemical, physical, infectious or genetic factors, as pointed out repeatedly in the text. Consequently, the definition of a malformation, as differing from an 'acquired' residual lesion was made dependant on evidence for the derangement of developmental pro- cesses subsequent to the acquisition of the disease.