Circulation of the Cerebrospinal Fluid: Demonstration of the Choroid Plexuses as the Generator of the Force for Flow of Fluid and Ventricular Enlargement

Abstract

T HIS paper presents an experimental test of the assumption that the force of formation of cerebrospinal fluid causes the eerebrospinal fluid to circulate and the ventricles to enlarge when its pathways are blocked. These experiments show that this assmnption is wrong and a new description of the circulation of the cerebrospinal fluid is given. I t has always been assumed that the cerebral ventricular enlargement of hydroeephalus was caused by the back pressure of blocked circulation of the cerebrospinal fluid, but this has never been put to experimental test. The clinical facts of hydroeephalus leave no doubt that if some cerebrospinal fluid escapes from the cerebral ventricles internal hydrocephalus will be prevented or cured, if established, and experimental work has generally confirmed these facts. TM Dandy, 4 in his experiments on hydrocephalus and formation of cerebrospinal fluid in dogs, removed the choroid plexus from one lateral cerebral ventricle, plugged the foramen of Monro on the same side, and then occluded the aqueduct of Sylvius. In this animal there was an enlargement of the ventricle with the choroid plexus present and the foramen of Monro open, while the other lateral ventricle remained unchanged. This was interpreted as demonstrating that the choroid plexus produced the cerebrospinal fuid, and this has remained as the basic experimental work showing that the choroid plexuses were the major source of