Adult Central Nervous System

Abstract

Historically, the central nervous system (CNS) was regarded as relatively immune to the effects of ionising radiation, and the recognition of the CNS as a radiovulnerable structure occurred later than was the case for many other tissues. Increasingly precise knowledge of the time-dose-volume relationships has allowed (1) the avoidance of catastrophic and often lethal effects in brain and spinal cord when these tissues are unavoidably irradiated during the treatment of adjacent non-CNS tumours, (2) the identification of a group (unfortunately small) of truly radiocurable CNS malignant tumours, and (3) the control of certain technically benign but potentially lethal lesions such as pituitary adenomas, arteriovenous malformations and some meningiomas, many of which are sensitive to radiation doses that are compatible with the longterm functional integrity of the CNS.