OBSERVATIONS ON THE CEREBROSPINAL FLUID PRESSURE ON SIMULTANEOUS VENTRICULAR AND LUMBAR PUNCTURES

Abstract

THE investigations which form the basis of this report were undertaken with the object of determining the relations existing between the ventricular and lumbar cerebrospinal fluid pressures. In the past it seems to have been taken for granted that the pressure within the cerebral ventricles is always in equilibrium with the pressure throughout the entire extent of the spinal subarachnoid space, except, of course, in the presence of spinal block. From time to time, however, it has been suggested that obstruction at the foramen magnum by herniation of the cerebellar tonsils in cases of intracranial tumour might possibly cause a state of partial block. This suggestion has generally been advanced in explanation of the not unusual finding of a normal, or even subnormal, lumbar pressure despite the presence of clinical signs indicative of high intracranial pressure.