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Rhomboid Fossa
The rhomboid fossa is a rhombus-shaped depression that is the anterior part of the fourth ventricle. Its anterior wall, formed by the back of the pons and the medulla oblongata, constitutes the floor of the fourth ventricle. It is covered by a thin layer of grey matter continuous with that of the spinal cord; 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 :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 :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 li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhombus
In plane Euclidean geometry, a rhombus (plural rhombi or rhombuses) is a quadrilateral whose four sides all have the same length. Another name is equilateral quadrilateral, since equilateral means that all of its sides are equal in length. The rhombus is often called a "diamond", after the diamonds suit in playing cards which resembles the projection of an octahedral diamond, or a lozenge, though the former sometimes refers specifically to a rhombus with a 60° angle (which some authors call a calisson after the French sweet – also see Polyiamond), and the latter sometimes refers specifically to a rhombus with a 45° angle. Every rhombus is simple (non-self-intersecting), and is a special case of a parallelogram and a kite. A rhombus with right angles is a square. Etymology The word "rhombus" comes from grc, ῥόμβος, rhombos, meaning something that spins, which derives from the verb , romanized: , meaning "to turn round and round." The word was used both by Eucl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medial Eminence
In the human brain, the rhomboid fossa is divided into symmetrical halves by a median sulcus which reaches from the upper to the lower angles of the fossa and is deeper below than above. On either side of this sulcus is an elevation, the medial eminence, bounded laterally by a sulcus, the sulcus limitans. In the superior part of the fossa the medial eminence has a width equal to that of the corresponding half of the fossa, but opposite the superior fovea it forms an elongated swelling, the ''colliculus facialis'', which overlies the nucleus of the abducent nerve, and is, in part at least, produced by the internal genu of the facial nerve The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of tas .... References External links * https://web.archive.org/web/20081224022115/http://isc.temple.ed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gracile Nucleus
In neuroanatomy, the dorsal column nuclei are a pair of nuclei in the dorsal columns in the brainstem. The name refers collectively to the cuneate nucleus and gracile nucleus, which are present at the bottom of the medulla oblongata. Both nuclei contain second-order neurons of the dorsal column–medial lemniscus pathway, which carries fine touch and proprioceptive information from the body to the brain. Fibres reach the thalamus. Structure Nerve pathways The dorsal column nuclei each have an associated nerve tract in the spinal cord, the gracile fasciculus and the cuneate fasciculus. Both dorsal column nuclei contain synapses from afferent nerve fibers that have travelled in the spinal cord. They then send on second-order neurons of the dorsal column–medial lemniscal pathway. Neurons of the dorsal column nuclei eventually reach the midbrain and the thalamus. They send axons that form the internal arcuate fibers. These cross over at the sensory decussation to form th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Funiculus (neurology)
A funiculus or column is a small bundle of axons (nerve fibres), enclosed by the perineurium. A small nerve may consist of a single funiculus, but a larger nerve will have several funiculi collected together into larger bundles known as fascicles. Fascicles are bound together in a common membrane, the epineurium. Funiculi in the spinal cord are portions of white matter. Examples include: * Anterior funiculus of the spinal cord * Lateral funiculus of the spinal cord * Posterior funiculus of the spinal cord * Funiculus separans of the rhomboid fossa The rhomboid fossa is a rhombus-shaped depression that is the anterior part of the fourth ventricle. Its anterior wall, formed by the back of the pons and the medulla oblongata, constitutes the floor of the fourth ventricle. It is covered by a th ... References Neuroanatomy {{Neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Funiculus Separans
The cells of the dorsal nucleus of vagus nerve are spindle-shaped, like those of the posterior column of the spinal cord, and the nucleus is usually considered as representing the base of the posterior column. It measures about 2 cm. in length, and in the lower, closed part of the medulla oblongata is situated behind the dorsal nucleus of the vagus; whereas in the upper, open part it lies lateral to that nucleus, and corresponds to an eminence, named the vagal trigone (ala cinerea), in the rhomboid fossa. The vagal trigone is separated from the area postrema by a narrow strip of thickened ependyma The ependyma is the thin Neuroepithelial cell, neuroepithelial (Simple columnar epithelium, simple columnar ciliated epithelium) lining of the ventricular system of the brain and the central canal of the spinal cord. The ependyma is one of the fou ... – the funiculus separans. References External links * https://web.archive.org/web/20070927162218/http://www.ib.amwaw.edu.pl/an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glossopharyngeal Nerves
The glossopharyngeal nerve (), also known as the ninth cranial nerve, cranial nerve IX, or simply CN IX, is a cranial nerve that exits the brainstem from the sides of the upper medulla, just anterior (closer to the nose) to the vagus nerve. Being a mixed nerve (sensorimotor), it carries afferent sensory and efferent motor information. The motor division of the glossopharyngeal nerve is derived from the basal plate of the embryonic medulla oblongata, whereas the sensory division originates from the cranial neural crest. Structure From the anterior portion of the medulla oblongata, the glossopharyngeal nerve passes laterally across or below the flocculus, and leaves the skull through the central part of the jugular foramen. From the superior and inferior ganglia in jugular foramen, it has its own sheath of dura mater. The inferior ganglion on the inferior surface of petrous part of temporal is related with a triangular depression into which the aqueduct of cochlea opens. O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sensory Nucleus Of The Vagus
{{Disambiguation ...
Sensory may refer to: Biology * Sensory ecology, how organisms obtain information about their environment * Sensory neuron, nerve cell responsible for transmitting information about external stimuli * Sensory perception, the process of acquiring and interpreting sensory information * Sensory receptor, a structure that recognizes external stimuli * Sensory system, part of the nervous system of organisms Business and brands * Sensory, Inc., an American speech technology company Other uses * Sensory analysis, a consumer product-testing method * Sensory garden, a self-contained garden area that allows visitors to enjoy a wide variety of sensory experiences See also * Sensor * Sense (other) A sense in biology and psychology, is a physiological mechanism that supports perception. Sense also may refer to: Music * Sense (band), a synthpop trio featuring Paul K. Joyce * Sense (In the Nursery album), ''Sense'' (In the Nursery album), 199 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vagal Trigone
The cells of the dorsal nucleus of vagus nerve are spindle-shaped, like those of the posterior column of the spinal cord, and the nucleus is usually considered as representing the base of the posterior column. It measures about 2 cm. in length, and in the lower, closed part of the medulla oblongata is situated behind the dorsal nucleus of the vagus; whereas in the upper, open part it lies lateral to that nucleus, and corresponds to an eminence, named the vagal trigone (ala cinerea), in the rhomboid fossa. The vagal trigone is separated from the area postrema by a narrow strip of thickened ependyma The ependyma is the thin Neuroepithelial cell, neuroepithelial (Simple columnar epithelium, simple columnar ciliated epithelium) lining of the ventricular system of the brain and the central canal of the spinal cord. The ependyma is one of the fou ... – the funiculus separans. References External links * https://web.archive.org/web/20070927162218/http://www.ib.amwaw.edu.pl/an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypoglossal Trigone
In the upper part of the medulla oblongata, the hypoglossal nucleus approaches the rhomboid fossa The rhomboid fossa is a rhombus-shaped depression that is the anterior part of the fourth ventricle. Its anterior wall, formed by the back of the pons and the medulla oblongata, constitutes the floor of the fourth ventricle. It is covered by a th ..., where it lies close to the middle line, under an eminence named the hypoglossal trigone. It is a slight elevation in the floor of the inferior recess of the fourth ventricle, beneath which is the nucleus of origin of the twelfth cranial nerve. References and the ''Free Medical Dictionary.'' External links * https://web.archive.org/web/20070927162218/http://www.ib.amwaw.edu.pl/anatomy/atlas/image_04be.htm *https://medical-dictionary.thefreedictionary.com/hypoglossal+trigone Cranial nerve nuclei {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Fovea
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Inferior may refer to: * Inferiority complex * An anatomical term of location * Inferior angle of the scapula, in the human skeleton * ''Inferior'' (book), by Angela Saini * ''The Inferior'', a 2007 novel by Peadar Ó Guilín See also *Junior (other) Junior or Juniors may refer to: Arts and entertainment Music * ''Junior'' (Junior Mance album), 1959 * ''Junior'' (Röyksopp album), 2009 * ''Junior'' (Kaki King album), 2010 * ''Junior'' (LaFontaines album), 2019 Films * ''Junior'' (1994 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Facial Colliculus
The facial colliculus is an elevated area located in the pontine tegmentum (dorsal pons), within the floor of the fourth ventricle (i.e. the rhomboid fossa). It is formed by fibres from the facial motor nucleus looping over the abducens nucleus. The facial colliculus is an essential landmark of the rhomboid fossa. Anatomy The facial colliculus occurs within the rhomboid fossa (i.e. the floor of the fourth ventricle) where it is placed lateral to its (midline) median sulcus. Structure The facial colliculus is formed by brachial motor nerve fibres of the facial nerve (CN VII) looping over the (ipsilateral) abducens nucleus, forming a bump upon the surface. Clinical significance A facial colliculus lesion would result in ipsilateral facial paralysis (i.e. Bell's palsy Bell's palsy is a type of facial paralysis that results in a temporary inability to control the facial muscles on the affected side of the face. In most cases, the weakness is temporary and significantly imp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substantia Ferruginea
The substantia ferruginea is an underlying patch of deeply pigmented nerve cells located in the floor of the superior part of the sulcus limitans. It was coined in 1838 and 1851. See also * Rhomboid fossa * Sulcus limitans * Locus ceruleus * 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 ve ... References External linksAtlas Image of the Posterior View of the Floor of Fourth Ventricle Brainstem {{Neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
