Rhomboid fossa

Information about Rhomboid fossa

Brain:
Hind-brain of a human embryo of three months—viewed from behind and partly from left side. (Rhomboid fossa labeled at center.)
Rhomboid fossa.
Latinf. rhomboidea
subject #187 798
NeuroNameshier-628
Dorlands/Elsevier f_14/12376599
The anterior part of the fourth ventricle is named, from its shape, the rhomboid fossa, and its anterior wall, formed by the back of the pons and medulla oblongata, constitutes the floor of the fourth ventricle.

It is covered by a thin layer of gray substance continuous with that of the medulla spinalis; superficial to this is a thin lamina of neuroglia which constitutes the ependyma of the ventricle and supports a layer of ciliated epithelium.

Parts

The fossa consists of three parts, superior, intermediate, and inferior.
  • The superior part is triangular in shape and limited laterally by the superior cerebellar peduncle; its apex, directed upward, is continuous with the cerebral aqueduct; its base is represented by an imaginary line at the level of the upper ends of the superior foveae.
  • The intermediate part extends from this level to that of the horizontal portions of the taeniae of the ventricle; it is narrow above where it is limited laterally by the middle peduncle, but widens below and is prolonged into the lateral recesses of the ventricle.
  • The inferior part is triangular, and its downwardly directed apex, named the calamus scriptorius, is continuous with the central canal of the closed part of the medulla oblongata.
The sulcus limitans forms the lateral boundary of the medial eminence.

Features

In the superior part of the rhomboid fossa it corresponds with the lateral limit of the fossa and presents a bluish-gray area, the locus cæruleus, which owes its color to an underlying patch of deeply pigmented nerve cells, termed the substantia ferruginea.

At the level of the colliculus facialis the sulcus limitans widens into a flattened depression, the superior fovea, and in the inferior part of the fossa appears as a distinct dimple, the inferior fovea.

Lateral to the foveæ is a rounded elevation named the area acustica, which extends into the lateral recess and there forms a feebly marked swelling, the tuberculum acusticum.

Winding around the inferior peduncle and crossing the area acustica and the medial eminence are a number of white strands, the striæ medullares, which form a portion of the cochlear division of the acoustic nerve and disappear into the median sulcus.

Below the inferior fovea, and between the trigonum hypoglossi and the lower part of the area acustica is a triangular dark field, the ala cinerea, which corresponds to the sensory nucleus of the vagus and glossopharyngeal nerves.

The lower end of the ala cinerea is crossed by a narrow translucent ridge, the funiculus separans, and between this funiculus and the clava, is a small tongue-shaped area, the area postrema.

On section it is seen that the funiculus separans is formed by a strip of thickened ependyma, and the area postrema by loose, highly vascular, neuroglial tissue containing nerve cells of moderate size.

Additional images


Hind- and mid-brains; postero-lateral view.

Figure showing the mode of innervation of the Recti medialis and lateralis of the eye.




This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.

 •  • [ e]
Brain: rhombencephalon (hindbrain)
Myelencephalon/medulla
anterior/ventral: Arcuate nucleus of medulla • Pyramid (Decussation) • Olivary body • Inferior olivary nucleus • Anterior median fissure • Ventral respiratory group posterior/dorsal: VII,IX,X: Solitary/tract • XII, X: Dorsal • IX,X,XI: Ambiguus • IX: Inferior salivatory nucleus • Gracile nucleus/Cuneate nucleus/Accessory cuneate nucleus • Area postrema • Posterior median sulcus • Dorsal respiratory group raphe/reticular: Sensory decussation • Reticular formation (Gigantocellular nucleus, Parvocellular reticular nucleus, Ventral reticular nucleus, Lateral reticular nucleus, Paramedian reticular nucleus) • Raphe nuclei (Obscurus, Magnus, Pallidus) tracts: Corticospinal tract (Lateral, Anterior) • Inferior cerebellar peduncle • Olivocerebellar tract • Spinocerebellar (Dorsal, Ventral) • Spinothalamic tract • PCML (Posterior external arcuate fibers, Internal arcuate fibers, Medial lemniscus) • Extrapyramidal (Rubrospinal tract, Vestibulospinal tract, Tectospinal tract)
Metencephalon/pons
Metencephalon/cerebellumVermis • Flocculus • Arbor vitae • Cerebellar tonsil • Inferior medullary velum
Molecular layer (Stellate cell, Basket cell, Parallel fiber) • Purkinje cell layer (Purkinje cell) • Granule cell layer (Golgi cell) • Mossy fibers • Climbing fiber
Deep cerebellar nuclei (Dentate, Emboliform, Globose, Fastigial)
Fourth ventricleapertures (Median, Lateral) • Rhomboid fossa (Vagal trigone, Hypoglossal trigone, Obex, Sulcus limitans, Facial colliculus, Medial eminence) • Lateral recess
Latin}}} 
Official status
Official language of: Vatican City
Used for official purposes, but not spoken in everyday speech
Regulated by: Opus Fundatum Latinitas
Roman Catholic Church
Language codes
ISO 639-1: la
ISO 639-2: lat
..... Click the link for more information.
NeuroNames is a system of nomenclature for the human and/or macaque brain.

It is maintained by the University of Washington and is a part of a tool called "BrainInfo". BrainInfo helps one identify structures in the brain.
..... Click the link for more information.
Elsevier, the world's largest publisher of medical and scientific literature, forms part of the Reed Elsevier group. Based in Amsterdam, the company has substantial operations in the UK, USA and elsewhere.
..... Click the link for more information.
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 ventricle.
..... Click the link for more information.
The pons (sometimes pons Varolii after Costanzo Varolio) is a structure located on the brain stem. It is rostral to the medulla oblongata, caudal to the midbrain, and ventral to the cerebellum.
..... Click the link for more information.
The medulla oblongata is the lower portion of the brainstem.

Location

By anatomical terms of location, it is rostral to the spinal cord and caudal to the pons, which is in turn ventral to the cerebellum.
..... Click the link for more information.
spinal chord is a thin, tubular bundle of nerves that is an extension of the central nervous system from the brain and is enclosed in and protected by the bony vertebral column.
..... Click the link for more information.
Glial cells, commonly called neuroglia or simply glia (greek for "glue"), are non-neuronal cells that provide support and nutrition, maintain homeostasis, form myelin, and participate in signal transmission in the nervous system.
..... Click the link for more information.
The superior cerebellar peduncles (brachia conjunctiva), two in number, emerge from the upper and medial part of the white substance of the hemispheres and are placed under cover of the upper part of the cerebellum.
..... Click the link for more information.
Taenia (Latin for "flat band") can refer to:
  • Taenia (tapeworm)
  • Taenia (architecture)
  • Taenia thalami
  • Taenia of fourth ventricle

..... Click the link for more information.
The lateral recess is a projection of the fourth ventricle which extends into the inferior cerebellar peduncle of the brainstem.


..... Click the link for more information.
The Locus ceruleus, also spelled locus caeruleus or locus coeruleus (Latin for 'the blue spot'), is a nucleus in the brain stem responsible for physiological responses to stress and panic.

The locus ceruleus was first discovered by Félix Vicq-d'Azyr.
..... Click the link for more information.
vagal trigone (ala cinerea), in the rhomboid fossa.

Additional images



Rhomboid fossa.


External links

  • http://www.ib.amwaw.edu.pl/anatomy/atlas/image_04be.

..... Click the link for more information.
Funiculus (Latin for "slender rope") commonly refers to:
  • in neurology, a bundle of nerve fibers, such as:
  • Anterior funiculus of the spinal cord

..... Click the link for more information.
Clava can refer to:
  • Mu Boötis, a triple star system in the constellation Boötes.
  • Clava cairn, a type of Bronze Age circular chamber tomb cairn.
  • gracile tubercle

..... Click the link for more information.
Public domain comprises the body of knowledge and innovation (especially creative works such as writing, art, music, and inventions) in relation to which no person or other legal entity can establish or maintain proprietary interests within a particular legal jurisdiction.
..... Click the link for more information.
Henry Gray's Anatomy of the Human Body (or Gray's Anatomy as it has commonly been shortened) is an English-language human anatomy textbook widely regarded as a classic work on the subject.
..... Click the link for more information.
In animals, the brain or encephalon (Greek for "in the skull"), is the control center of the central nervous system, responsible for behavior. The brain is located in the head, protected by the skull and close to the primary sensory apparatus of vision, hearing,
..... Click the link for more information.
The rhombencephalon (or hindbrain) is a developmental categorization of portions of the central nervous system in vertebrates.

The rhombencephalon can be subdivided in a variable number of transversal swellings called rhombomeres.
..... Click the link for more information.
The myelencephalon is a developmental categorization of a portion of the central nervous system. The myelencephalon is composed of the medulla oblongata; contains a portion of the fourth ventricle; as well as the glossopharyngeal nerve (CN IX), vagus nerve (CN X), accessory nerve
..... Click the link for more information.
The medulla oblongata is the lower portion of the brainstem.

Location

By anatomical terms of location, it is rostral to the spinal cord and caudal to the pons, which is in turn ventral to the cerebellum.
..... Click the link for more information.
arcuate nucleus is a group of neurons located on the anterior surface of the medullary pyramids. They receive fibers from the corticospinal tract and send their axons through the external arcuate fibers and striae medullares to the cerebellum via the inferior cerebellar peduncle.
..... Click the link for more information.
The interior district of the medulla oblongata is named the pyramid and lies between the anterior median fissure and the antero-lateral sulcus.

Its upper end is slightly constricted, and between it and the pons the fibers of the abducent nerve emerge; a little below the
..... Click the link for more information.
pyramidal decussation.

Having crossed the middle line, they pass down in the posterior part of the lateral funiculus as the lateral cerebrospinal fasciculus.

Additional images



Diagrams of the medulla spinalis.

..... Click the link for more information.
In anatomy, the olivary bodies or simply olives (Latin oliva and olivae, singular and plural, respectively) are a pair of prominent oval structures in the medulla oblongata, the lower portion of the brainstem. They contain the olivary nuclei.
..... Click the link for more information.
The inferior olivary nucleus is the largest nucleus situated in the olivary body, part of the medulla oblongata.

It consists of a gray folded lamina arranged in the form of an incomplete capsule, opening medially by an aperture called the hilum.
..... Click the link for more information.
The anterior median fissure (ventral or ventromedian fissure) contains a fold of pia mater, and extends along the entire length of the medulla oblongata: it ends at the lower border of the pons in a small triangular expansion, termed the foramen cecum.
..... Click the link for more information.
The ventral respiratory group (VRG) is a column of neurons located in the ventrolateral region of the medulla, extending from the caudal facial nucleus to -400μm obex.
..... Click the link for more information.
The solitary nucleus and tract are structures in the brainstem that carry and receive visceral sensation and taste from the facial (VII), glossopharyngeal (IX), vagus (X) cranial nerves, as well as the cranial part of the accessory nerve (XI).
..... Click the link for more information.
The solitary tract (Latin: tractus solitarius) is a compact fiber bundle that extends longitudinally through the posterolateral region of the medulla. The solitary tract is surrounded by the nucleus of the solitary tract, and descends to the upper cervical segments
..... Click the link for more information.

This article is copied from an article on Wikipedia.org - the free encyclopedia created and edited by online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of the wikipedia encyclopedia articles provide accurate and timely information please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.