Covers the fourth ventricle as a fluid-filled cavity in the hindbrain between the brainstem and cerebellum, and its role in cerebrospinal fluid circulation. It describes the ventricle's extent and diamond, tent-shaped form, then its roof and floor (the rhomboid fossa) with their boundaries and medullary vela, followed by the lateral recesses and their exits to the subarachnoid space. It closes with the choroid plexus, its site, shape and arterial supply, and notes the ventricle's development from the neural tube's central canal.
Topic 130 of 236 in the MU Pleven syllabus for Anatomy Bones and Muscles (Medicine, Year 2). The free AceMed note covers it in 4 sections, about 282 words (2 min of reading), with 10 flashcards.
In this note
FOURTH VENTRICLE
Boundaries:
Recesses:
Choroid Plexus:
FOURTH VENTRICLE
The fourth ventricle is a fluid-filled cavity located in the hindbrain, between the brainstem and the cerebellum.
It is one of the four ventricles in the brain and plays a crucial role in the circulation & drainage of cerebrospinal fluid (CSF).
It extends from the cerebral aqueduct superiorly, to the central canal and spinal cord inferiorly.
It is lined by an epithelial layer called the ependyma.
Shape: Diamond-shaped when viewed in cross-section. tent-shaped when seen from the side.
Boundaries:
1 - Roof (Dorsal wall):
Composed of a thin layer of tissue known as the tela choroidea, which is continuous with the roof of the 3rd ventricle.
Formed by superior medullary velum
band of ependyma stretched btw the 2 sup. cerebellar peduncles.
and inferior medullary velum.
Floor (Ventral wall)
Also referred to as the rhomboid fossa.
It is visible into a right and left half by the posterior median sulcus, and into a superior & inferior triangle by the striae medullares.
