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Encyclopedia > Inferior petrosal sinus
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Several large dural sinuses, such as the superior and inferior sagittal sinuses, are visible with a sagittal cut through the brain.

The dural venous sinuses (also called dural sinuses or cerebral sinuses) are venous channels found between layers of dura mater in the brain. They receive blood from internal and external veins of the brain and ultimately empty into the internal jugular vein. Damage to the walls of the dural sinuses may result in dural sinus thrombosis. Comparative brain sizes In animals, the brain, or encephalon (Greek for in the head), acts as the control center of the central nervous system. ... In geology, a vein is a finite volume within a rock, having a distinct shape, filled with mono or poly mineralic crystal aggregates, which were precipitated from an (aqueous) fluid or melt. ... The dura mater (from the Latin hard mother), or pachymeninx, is the tough and inflexible outermost of the three layers of the meninges surrounding the brain. ... Comparative brain sizes In animals, the brain, or encephalon (Greek for in the head), acts as the control center of the central nervous system. ... Red blood cells (erythrocytes) are present in the blood and help carry oxygen to the rest of the cells in the body Blood is a circulating tissue composed of fluid plasma and cells (red blood cells, white blood cells, platelets). ... In geology, a vein is a finite volume within a rock, having a distinct shape, filled with mono or poly mineralic crystal aggregates, which were precipitated from an (aqueous) fluid or melt. ... The external and internal jugular veins are veins that bring deoxygenated blood from the head back to the heart via the superior vena cava. ...

Contents


Venous sinuses

Superior sagittal sinus

The superior sagittal sinus lies within the superior border of the falx cerebri, a two-layered dural structure separating the two cerebral hemispheres. It begins at the crista galli, near the origin of the falx cerebri, and terminates at the confluence of sinuses. The superior sagittal sinus is usually continuous with the right transverse sinus. The falx cerebri (Latin: scythe of the brain) is an extension of the protective dura mater that projects into the longitudinal fissure that seperates the two cerebral hemispheres. ... The dura mater (from the Latin hard mother), or pachymeninx, is the tough and inflexible outermost of the three layers of the meninges surrounding the brain. ... The crista galli (Latin: crest of the cock) is a median ridge of bone that projects from the cribriform plate of the ethmoid bone. ...


The surrounding dura mater contains a number of blood-filled venous lacunae which open into the superior sagittal sinus. Blood from nearby veins may drain into the superior sagittal sinus directly or indirectly via these lacunae. Ultimately, the superior sagittal sinus drains blood from the superior cerebral, emissary, and diploic veins, as well as various unnamed veins on the superficial surface of the brain.


Inferior sagittal sinus

The smaller inferior sagittal sinus courses along the inferior border of the falx cerebri, superior to the corpus callosum. It receives blood from the deep and medial aspects of the cerebral hemispheres and drains into the straight sinus. Grays FIG. 733– Corpus callosum from above. ...


Straight sinus

The straight sinus lies in the falx cerebri superior to the tentorium cerebelli, a bilayer of dura mater superior to the cerebellum. The straight sinus receives blood from the inferior sagittal sinus as well as from the great cerebral vein of Galen. It is usually continuous with the left transverse sinus. 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. ... Figure 1a: A human brain, with the cerebellum in purple. ...


Occipital sinus

The occipital sinus courses through falx cerebelli, inferior to the straight sinus. It drains blood from veins inferior to the cerebellum.


Confluence of sinuses

The superior sagittal, straight, and occipital sinuses connect at a series of channels that comprise the confluence of sinuses, which is found beneath the occipital protuberance of the skull. They drain blood into the right and left transverse sinuses. An older, Latinate term for the confluence of sinuses is torcula herophili. A hippopotamus skull A skull, or cranium, is a bony structure of Craniates which serves as the general framework for a head. ...


Transverse sinuses

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The transverse sinuses are formed by the tentorium cerebelli and drain into the right and left sigmoid sinuses.

The transverse (or lateral) sinuses are formed within the tentorium cerebelli and course along a groove in the occipital bone. They carry venous blood from the confluence of sinuses and superior sagittal sinus towards the temporal bone, where it is drained into the right and left sigmoid sinuses. 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. ... The occipital bone [Fig. ... The temporal bones (os temporales) are situated at the sides and base of the skull. ...


Sigmoid sinuses

Each sigmoid sinus begins beneath the temporal bone and follows a tortuous course to the jugular foramen, at which point the sinus becomes continuous with the internal jugular vein. The temporal bones (os temporales) are situated at the sides and base of the skull. ... The external and internal jugular veins are veins that bring deoxygenated blood from the head back to the heart via the superior vena cava. ...


Petrosal sinuses

The four petrosal sinuses drain venous blood from the paired cavernous sinuses (which are not actually sinuses; rather, they are a collection of thin-walled veins that lie outside the dura mater). The superior petrosal sinuses deliver blood to the transverse sinuses, while the inferior petrosal sinuses deliver blood directly to the internal jugular veins or indirectly via the sigmoid sinuses. They are often referred to as the greater and lesser petrosal veins. 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. ...


Structure

The walls of the dural venous sinuses are composed of dura mater lined with endothelium, a specialized layer of flattened cells found in blood vessels. They differ from other blood vessels in that they lack a full set of vessel layers (e.g. tunica media) characteristic of arteries and veins. The dura mater (from the Latin hard mother), or pachymeninx, is the tough and inflexible outermost of the three layers of the meninges surrounding the brain. ... The endothelium is the layer of thin, flat cells that lines the interior surface of blood vessels, forming an interface between circulating blood in the lumen and the rest of the vessel wall. ... Squamous cells are basically types of cells which can be identified histologically by the fact that they look flattened and thin under a microscope. ... The arterial system The blood vessels are part of the circulatory system and function to transport blood throughout the body. ... The tunica media (or just media) is the middle layer of an artery. ... Section of an artery An arterial road is a class of highway. ... In geology, a vein is a finite volume within a rock, having a distinct shape, filled with mono or poly mineralic crystal aggregates, which were precipitated from an (aqueous) fluid or melt. ...


Clinical relevance

Damage to the dura mater, which may be caused by skull fracture, may result blood clot formation (thrombosis) within the dural sinuses. While rare, dural sinus thrombosis may lead to hemorrhagic infarction with serious consequences including epilepsy, neurological deficits, or death. The dura mater (from the Latin hard mother), or pachymeninx, is the tough and inflexible outermost of the three layers of the meninges surrounding the brain. ... Thrombosis is the formation of a clot or thrombus inside a blood vessel, obstructing the flow of blood through the circulatory system. ... A subconjunctival hemorrhage is a common and relatively minor post-LASIK complication. ... In medicine, infarction is necrosis of tissue due to upstream obstruction of its arterial blood supply. ...


References

  • Kiernan, John A. (2005). Barr's The Human Nervous System: An Anatomical Viewpoint, 428-230, Lippincott Williams & Wilkins. ISBN 0-7817-5154-3.
  • de Bruijn SF, Stam J (1999). Randomized, placebo-controlled trial of anticoagulant treatment with low-molecular-weight heparin for cerebral sinus thrombosis. Stroke 30 (3): 484-8. PMID 10066840.

  Results from FactBites:
 
Inferior petrosal sinus - Wikipedia, the free encyclopedia (334 words)
The inferior petrosal sinus is situated in the inferior petrosal sulcus formed by the junction of the petrous part of the temporal with the basilar part of the occipital.
It begins in the postero-inferior part of the cavernous sinus, and, passing through the anterior part of the jugular foramen, ends in the superior bulb of the internal jugular vein.
The inferior petrosal sinus receives the internal auditory veins and also veins from the medulla oblongata, pons, and under surface of the cerebellum.
Superior petrosal sinus - Wikipedia, the free encyclopedia (278 words)
The superior petrosal sinuses (or greater petrosal veins) deliver blood to the transverse sinuses, while the inferior petrosal sinuses deliver blood directly to the internal jugular veins or indirectly via the sigmoid sinuses.
Along with the inferior petrosal sinus, they drain venous blood from the paired cavernous sinuses.
The superior petrosal sinus, small and narrow, connects the cavernous with the transverse sinus.
  More results at FactBites »

 
 

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