The Ventricular System: Anatomy and Common Lesions

Abstract

The ventricular system is an interesting and complex area of the central nervous system. It is bordered by some of the most important and eloquent areas of the brain and can give rise to a wide variety of pathological conditions. Many of these pathologies are unique and cannot be found anywhere else in the body, including the brain tissue proper. The paired C-shaped lateral ventricles are the largest structures of the system and are connected to the third ventricle via the foramen of Monro. The lateral ventricles are frequently accessed for a variety of shunting and endoscopic procedures to create alternative pathways for the flow of cerebral spinal fluid. The foramen of Monro then leads caudally through the third ventricle and cerebral aqueduct to the fourth ventricle. The floor of the fourth ventricle is an operatively complex area that surgeons might encounter because of an obstructive pathology in the area, such as an ependymoma or subependymoma. This chapter discusses the salient surgical anatomy of the cerebral ventricular system in the context of common pathological conditions that can be encountered.