INTRACRANIAL PRESSURE CHANGES DURING FORCED DRAINAGE OF THE CENTRAL NERVOUS SYSTEM

Abstract

In recent studies of the cellular response of the central nervous system to subarachnoid injections of trypan blue, four facts developed which gave rise to this investigation (Kubie and Shults¹): (a) Early in the acute stage of a meningeal irritation, and throughout all later stages, the perivascular spaces and many minute crevices of the central nervous system become lined with small mononuclear cells which we believe to be lymphocytes. (b) Prolonged drainage of the subarachnoid space during the meningeal reaction is accompanied by a gradual alteration of the proportions of the various cells of the cerebrospinal fluid; the lymphocytes increase in relative abundance in the late fractions of the fluid, and finally, in many cases, far outnumber the other elements. (c) Intravenous injections of isotonic or hypotonic solutions which are begun when the spontaneous flow of fluid has almost ceased are accompanied by a renewed outflow of fluid, and