THE MORPHOLOGY OF THE PIAL BLOOD VESSELS AND ITS BEARING ON THE FORMATION AND ABSORPTION OF THE CEREBROSPINAL FLUID

Abstract

Hassin states that the pial arteries and veins possess, in addition to the well-established tunics, an additional layer which may be termed periadventitia. This is, in turn, invested with mesothelial cells. The author concludes that the complex structure of a pial blood vessel precludes the assumption that the spinal fluid originates from the blood vessels by the process of dialyzation, and that it is also absorbed by them.