The choroid plexus is made up of a mass of blood vessels surrounded everywhere by a layer of delicate connective tissue. This connective tissue layer is the basement membrane for the ependymal cells, which form the outer surface of the plexus, and which are continuous with the ependymal covering of the ventricular walls.
Two types of blood vessels make up the choroid plexus. One group has the usual structure of the arterial system, and lies in the midst of the plexus. Those of the second type are thin walled vessels, on which the ependymal layer with its underlying connective tissue, is applied, forming a finely villous structure.
The blood supply in man is obtained from the anterior choroid branch of the internal carotid and the posterolateral choroid, a branch of the posterior cerebral. The return of venous blood is through the choroid vein into the internal cerebral veins which join
TAFT AE. A NOTE ON THE PATHOLOGY OF THE CHOROID PLEXUS IN GENERAL PARALYSIS. Arch NeurPsych. 1922;7(2):177-182. doi:10.1001/archneurpsyc.1922.02190080026003