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Encyclopedia > Body of sphenoid bone
Bone: Body of sphenoid bone
Figure 2: Sphenoid bone, anterior and inferior surfaces.
Figure 3: Sphenoid bone, upper and posterior surfaces.
Latin corpus ossis sphenoidalis
Gray's subject #35 147
Dorlands/Elsevier c_56/12260702

The body of the sphenoid bone, more or less cubical in shape, is hollowed out in its interior to form two large cavities, the sphenoidal air sinuses, which are separated from each other by a septum. Figure 1 : Sphenoid bone, upper surface. ... Latin is an ancient Indo-European language originally spoken in Latium, the region immediately surrounding Rome. ... Elseviers logo. ... Figure 1 : Sphenoid bone, upper surface. ... Three dimensions A cube (or hexahedron) is a Platonic solid composed of six square faces, with three meeting at each vertex. ... Look up septum in Wiktionary, the free dictionary. ...

Contents

Superior surface

The superior surface of the body [Fig. 1] presents in front a prominent spine, the ethmoidal spine, for articulation with the cribriform plate of the ethmoid bone; behind this is a smooth surface slightly raised in the middle line, and grooved on either side for the olfactory lobes of the brain. The superior surface of the body of the sphenoid bone (Fig. ... The cribriform plate of the ethmoid bone (horizontal lamina) [Fig. ... Your skull is in your back (this is obviously not true, I was just testing the website to see if it really works) The ethmoid bone (os ethmoidale) is a bone in the skull that separates the nasal cavity from the brain. ... In animals, the brain, or encephalon (Greek for in the head), is the control center of the central nervous system. ...


This surface is bounded behind by a ridge, which forms the anterior border of a narrow, transverse groove, the prechiasmatic groove, above and behind which lies the optic chiasma; the groove ends on either side in the optic foramen, which transmits the optic nerve and ophthalmic artery into the orbital cavity. The optic chiasm is the part of the brain where the optic nerves partially cross, those parts of the right eye which see things on the right side being connected to the left side of the brain, and vice versa. ... The superior surface of the sphenoid bone is bounded behind by a ridge, which forms the anterior border of a narrow, transverse groove, the chiasmatic groove (optic groove), above and behind which lies the optic chiasma; the groove ends on either side in the optic foramen, which transmits the optic... MRI scan of human eye showing optic nerve. ... The opthalmic artery is a branch of the internal carotid artery which supplies branches to supply the eye and other structures in the orbit: Central retinal artery Supraorbital artery Supratrochlear artery Lacrimal artery Dorsal nasal artery Short posterior ciliary arteries Long posterior ciliary arteries Posterior ethmoidal artery Anterior ethmoidal artery... In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. ...


Behind the chiasmatic groove is an elevation, the tuberculum sellae; and still more posteriorly, a deep depression, the sella turcica (the Turkish saddle), the deepest part of which lodges the pituitary gland and is known as the hypophyseal fossa. The Sella turcica (literally Turkish saddle) is a saddle-shaped depression in the sphenoid bone at the base of the human skull. ... The pituitary gland, or hypophysis, is an endocrine gland about the size of a pea that sits in a small, bony cavity (sella turcica) at the base of the brain. ... The Sella turcica (literally Turkish saddle) is a saddle-shaped depression in the sphenoid bone at the base of the human skull. ...


The anterior boundary of the sella turcica is completed by two small eminences, one on either side, called the middle clinoid processes, while the posterior boundary is formed by a square-shaped plate of bone, the dorsum sellae, ending at its superior angles in two tubercles, the posterior clinoid processes, the size and form of which vary considerably in different individuals. The Sella turcica (literally Turkish saddle) is a saddle-shaped depression in the sphenoid bone at the base of the human skull. ... In the sphenoid bone, the anterior boundary of the sella turcica is completed by two small eminences, one on either side, called the middle clinoid processes, while the posterior boundary is formed by a square-shaped plate of bone, the dorsum sellæ, ending at its superior angles in two tubercles...


The posterior clinoid processes deepen the sella turcica, and give attachment to the tentorium cerebelli. The tentorium cerebelli (Latin: tent of the cerebellum) is an extension of the dura mater that seperates the cerebellum from the inferior portion of the occipital lobes. ...


On either side of the dorsum sellae is a notch for the passage of the abducent nerve, and below the notch a sharp process, the petrosal process, which articulates with the apex of the petrous portion of the temporal bone, and forms the medial boundary of the foramen lacerum. The sixth out of twelve cranial nerves, the abducens nerve controls the lateral rectus muscle - this means that the action of this nerve controls each eyes ability to look laterally (away from the midline). ... The temporal bones (os temporales) are situated at the sides and base of the skull. ... The foramen lacerum (Latin for lacerated piercing) is a triangular hole in the base of the skull located at the base of the medial pterygoid plate. ...


Behind the dorsum sellae is a shallow depression, the clivus, which slopes obliquely backward, and is continuous with the groove on the basilar portion of the occipital bone; it supports the upper part of the pons. The occipital bone [Fig. ... Position of the pons in the human brain The pons (sometimes pons Varolii after Costanzo Varolio) is a knob on the brain stem. ...


Lateral surfaces

The lateral surfaces of the body are united with the greater wings of the sphenoid and the medial pterygoid plates. The medial pterygoid plate of the sphenoid is narrower and longer than the lateral pterygoid plate; it curves lateralward at its lower extremity into a hook-like process, the pterygoid hamulus, around which the tendon of the Tensor veli palatini glides. ...


Above the attachment of each greater wing is a broad groove, curved something like the italic letter f; it lodges the internal carotid artery and the cavernous sinus, and is named the carotid sulcus. The carotid artery is a major artery of the head and neck that supplies blood to the head and neck. ... The cavernous sinus is a large channel of venous blood creating a sinus cavity bordered by the sphenoid bone and the temporal bone of the skull. ...


Along the posterior part of the lateral margin of this groove, in the angle between the body and greater wing, is a ridge of bone, called the sphenoidal lingula.


Posterior surfaces

The posterior surface, quadrilateral in form [Fig. 3], is joined, during infancy and adolescence, to the basilar part of the occipital bone by a plate of cartilage.


Between the eighteenth and twenty-fifth years this becomes ossified, ossification commencing above and extending downward.


Anterior surface

The anterior surface of the body [Fig. 2] presents, in the middle line, a vertical crest, the sphenoidal crest, which articulates with the perpendicular plate of the ethmoid, and forms part of the nasal septum. The ethmoid bone (os ethmoidale) is a bone in the skull that separates the nasal cavity from the brain. ... The nasal septum or septum nasi separates the left and right airways in the nose, dividing the two nostrils. ...


On either side of the crest is an irregular opening leading into the corresponding sphenoidal air sinus.


These sinuses are two large, irregular cavities hollowed out of the interior of the body of the bone, and separated from one another by a bony septum, which is commonly bent to one or the other side. Look up septum in Wiktionary, the free dictionary. ...


They vary considerably in form and size, are seldom symmetrical, and are often partially subdivided by irregular bony laminae.


Occasionally, they extend into the basilar part of the occipital bone nearly as far as the foramen magnum. They begin to be developed before birth, and are of a considerable size by the age of six. The occipital bone [Fig. ... In anatomy, the foramen magum is the large hole through the occipital bone in the base of the skull, through which the medulla oblongata (an extension of the spinal cord) exits the skull vault. ...


They are partially closed, in front and below, by two thin, curved plates of bone, the sphenoidal conchae, leaving in the articulated skull a round opening at the upper part of each sinus by which it communicates with the upper and back part of the nasal cavity and occasionally with the posterior ethmoidal air cells.


The lateral margin of the anterior surface is serrated, and articulates with the lamina papyracea of the ethmoid, completing the posterior ethmoidal cells; the lower margin articulates with the orbital process of the palatine bone, and the upper with the orbital plate of the frontal bone. The ethmoid bone (os ethmoidale) is a bone in the skull that separates the nasal cavity from the brain. ...


Inferior surface

The inferior surface presents, in the middle line, a triangular spine, the sphenoidal rostrum, which is continuous with the sphenoidal crest on the anterior surface, and is received in a deep fissure between the alæ of the vomer.


On either side of the rostrum is a projecting lamina, the vaginal process, directed medialward from the base of the medial pterygoid plate, with which it will be described. This article is about the leaf, a plant organ. ... The medial pterygoid plate of the sphenoid is narrower and longer than the lateral pterygoid plate; it curves lateralward at its lower extremity into a hook-like process, the pterygoid hamulus, around which the tendon of the Tensor veli palatini glides. ...



 
 

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