Definition

Noun: - A cavity in the brain: The fourth ventricle is an irregularly shaped, fluid-filled cavity located within the brainstem, between the third ventricle (above) and the central canal of the spinal cord (below). It is part of the ventricular system that contains cerebrospinal fluid.

Usage

The term "fourth ventricle" is used specifically in anatomical and medical contexts to describe this particular structure. - The tumor was located adjacent to the fourth ventricle. - Cerebrospinal fluid flows from the third ventricle into the fourth ventricle.

Advanced Usage

• "Fourth ventricle outlet": Refers to the openings (foramina) in the fourth ventricle that allow cerebrospinal fluid to flow into the subarachnoid space.
  • Obstruction of the fourth ventricle outlets can cause hydrocephalus.

Variants and Related Words

• Ventricle (noun): A general term for any of the system of communicating cavities in the brain.
  • The lateral ventricles are the largest.
• Ventricular (adjective): Pertaining to a ventricle.
  • The ventricular system is essential for CSF circulation.

Synonyms

• Cavity of the rhombencephalon: A more technical synonym, as the fourth ventricle is located within the hindbrain (rhombencephalon).

Related Phrases

• Floor of the fourth ventricle: The ventral surface of this cavity, which forms part of the brainstem.
  • Important cranial nerve nuclei are located in the floor of the fourth ventricle.
• Roof of the fourth ventricle: The dorsal surface of this cavity.
  • The fourth ventricle roof is partially formed by the cerebellum.

Noun

1. an irregular ventricle between the third ventricle and the central canal of the spinal cord