The perispinal spaces. Constitution, organization and relations with the cerebrospinal fluid (CSF).

In this study the structures of the three meningeal membranes which surround the spinal cord and delineate the perispinal spaces are described. The pia mater is composed of a deep layer and a superficial layer. This structural arrangement accounts for the relations of the pia mater with the spinal vessels and the cerebrospinal fluid (CSF). The morphology, structure and landmark value of the denticulate ligament are then defined. Following a brief description of the dura mater and the arachnoidea, the arrangement of the meningeal sleeves of the spinal nerves is detailed. Meningeal structures similar to the cranial arachnoidal granulations are described, and the question of CSF physiology is considered. The secretion and circulation of the CSF are briefly described, and the problem of spinal resorption is discussed. CSF resorption can be effected by ascending, lymphatic or venous routes.