This article will address the topic of Median aperture, which represents a point of interest and relevance today. Median aperture is a topic that has aroused the interest of many, since it has important implications in different areas of daily life. Along the following lines, Median aperture will be analyzed from different perspectives, in order to provide a comprehensive and complete vision of this topic. From its origin to its impact on society, Median aperture is a topic that generates great debate and interest, which is why it is essential to delve into its study to understand its scope and relevance in the contemporary world.
Median aperture | |
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![]() Scheme of roof of fourth ventricle. The arrow is in the median aperture. | |
Details | |
Identifiers | |
Latin | apertura mediana |
NeuroNames | 641 |
TA98 | A14.1.05.722 |
TA2 | 5970 |
FMA | 75015 |
Anatomical terms of neuroanatomy |
The median aperture (median aperture of fourth ventricle or foramen of Magendie) is an opening at the caudal portion of the roof of the fourth ventricle.[1] It allows the flow of cerebrospinal fluid (CSF) from the fourth ventricle into the cisterna magna.[2][3] The other openings of the fourth ventricle are the lateral apertures - one on either side.[4] The median aperture varies in size but accounts for most of the outflow of CSF from the fourth ventricle. [1]
The median foramen on axial images is posterior to the pons and anterior to the caudal cerebellum. It is surrounded by the obex and gracile tubercles of the medulla, tela choroidea of the fourth ventricle and its choroid plexus, which is attached to the cerebellar vermis.[4][5]
The foramen of Magendie is named for François Magendie, who first described it.[6] The term "foramen of Magendie" is commonly used, and this opening is frequently described and illustrated as a foramen in the inferior roof of the fourth ventricle. However, the opening is an aperture, rather than a foramen.[5]
The choroid plexuses are highly vascular structures that project into each of the ventricles and continuously produce cerebrospinal fluid by active secretion from the blood. CSF escapes from the fourth ventricle (to the subarachnoid space) via three openings: the single median aperture and the two lateral apertures. It is ultimately reabsorbed into the venous system via the arachnoid granulations which run along the superior aspect of the cerebral hemispheres ... correspond to the arachnoid villi, finger-like projections into a large venous channel called the superior sagittal sinus.
CSF is produced by the choroid plexuses of the lateral, third, and fourth ventricle. The production of CSF is not pressure regulated, and it continues to be produced even if the reabsorption mechanisms are obstructed. The circulation of CSF is as follows: Lateral ventricle → interventricular foramen of Monroe → third ventricle → aqueduct of sylvius → fourth ventricle → foramen of Magendie (median aperture)/foramen of Luschka (lateral aperture) → subarachnoid space.