Fourth Ventricle Shown On The Anatomy Of The Brain

Description

Centered within the posterior fossa, the fourth ventricle appears as a CSF-filled cavity dorsal to the pons and open medulla and ventral to the cerebellum. As the camera advances and the brainstem rotates into a dorsal view, the ventricular floor (rhomboid fossa) is framed by the medial eminence and sulcus limitans, while the roof is formed by the superior and inferior medullary vela with the overlying cerebellar vermis. Superiorly the lumen narrows toward the cerebral aqueduct, and inferiorly it tapers toward the obex and central canal, with the lateral recesses extending laterally toward the foramina of Luschka. CSF dynamics make this space clinically concrete: obstruction at the cerebral aqueduct, fourth ventricular outlets (foramen of Magendie and foramina of Luschka), or the obex produces noncommunicating hydrocephalus with effacement of the fourth ventricle and mass effect on the brainstem. Tumors of the cerebellar vermis or fourth ventricular floor, including medulloblastoma and ependymoma, characteristically distort the roof and rhomboid fossa, and can compromise nuclei in the dorsal pons and medulla. Sequenced motion helps you track how a lesion displaces the ventricle relative to the cerebellum and brainstem, a relationship that can be hard to appreciate from a single axial slice. Use this animation for neuroanatomy and neuropathology teaching on ventricular anatomy, posterior fossa mass effect, and the pathways of CSF circulation, or to support radiology and neurosurgery content that correlates fourth-ventricle distortion with MRI findings and midline suboccipital approaches. Anatomical accuracy verified by SciePro's Medical Advisory Board.