The superior medullary velum (anterior medullary velum) is a thin, transparent

lamina Lamina may refer to: People * Saa Emerson Lamina, Sierra Leonean politician * Tamba Lamina, Sierra Leonean politician and diplomat Science and technology * Planar lamina, a two-dimensional planar closed surface with mass and density, in mathem ...

white matter White matter refers to areas of the central nervous system that are mainly made up of myelinated axons, also called Nerve tract, tracts. Long thought to be passive tissue, white matter affects learning and brain functions, modulating the distr ...

which - together with the

inferior medullary velum The inferior medullary velum (posterior medullary velum) is a thin layer of white substance, prolonged from the white center of the cerebellum, above and on either side of the nodule; it forms the infero-posterior part of the fourth ventricle Th ...

- forms the roof of the

fourth ventricle The fourth ventricle is one of the four connected fluid-filled cavities within the human brain. These cavities, known collectively as the ventricular system, consist of the left and right lateral ventricles, the third ventricle, and the fourth ...

. It extends between the two superior cerebellar peduncles. The lingula of cerebellum covers - and adheres to - its dorsal surface.

Anatomy

Relations

The superior medullary velum extends between the dorsomedial margins of the two superior cerebellar peduncles. On the dorsal surface of its lower half the

folia ''La Folía'' (Spanish), or ''Follies'' (English), also known as ''folies d'Espagne'' (French), ''La Follia'' (Italian), and ''Folia'' (Portuguese), is one of the oldest remembered European musical themes, or primary material, generally melodic, ...

and lingula are prolonged. It forms, together with the superior cerebellar peduncle, the roof of the upper part of the fourth ventricle; it is narrow above, where it passes beneath the facial colliculi, and broader below, where it is continuous with the white substance of the superior

vermis The cerebellar vermis (from Latin ''vermis,'' "worm") is located in the medial, cortico-nuclear zone of the cerebellum, which is in the posterior fossa of the cranium. The primary fissure in the vermis curves ventrolaterally to the superior s ...

. A slightly elevated ridge, the

frenulum veli The frenulum veli, or frenulum of superior medullary velum, also known as the ''frenulum veli medullaris superioris'', ''cerebellar frenulum'', or ''frenulum cerebelli'', is a slightly raised white band passing from the inferior end of the medial ...

, descends upon its upper part from between the inferior colliculi, and on either side of this the

trochlear nerve The trochlear nerve (), ( lit. ''pulley-like'' nerve) also known as the fourth cranial nerve, cranial nerve IV, or CN IV, is a cranial nerve that innervates a single muscle - the superior oblique muscle of the eye (which operates through the pu ...

emerges.

Blood supply

Blood is supplied by branches from the

superior cerebellar artery The superior cerebellar artery (SCA) is an artery of the head. It arises near the end of the basilar artery. It is a branch of the basilar artery. It supplies parts of the cerebellum, the midbrain, and other nearby structures. It is the cause of t ...

Additional images

File:Gray708.svg, Scheme of roof of fourth ventricle. 1. Posterior medullary velum 2. Choroid plexus 3. Cisterna cerebellomedullaris of subarachnoid cavity 4. Central canal 5. Corpora quadrigemina 6. Cerebral peduncle 7. Anterior medullary velum 8. Ependymal lining of ventricle 9. Cisterna pontis of subarachnoid cavity (Arrow = Flow of cerebrospinal fluid (CSF) through foramen of Magendie) File:Gray715.png, Mesal aspect of a brain sectioned in the median sagittal plane. File:Gray709.png, Rhomboid fossa. File:Human brain midsagittal view description.JPG, Human brain midsagittal view description File:Slide2PITER.JPG, Fourth ventricle. Posterioe view.Deep dissection.

References

External links