The superior sagittal sinus (also known as the superior longitudinal sinus), within the

human head In human anatomy, the head is at the top of the human body. It supports the face and is maintained by the skull, which itself encloses the brain. Structure The human head consists of a fleshy outer portion, which surrounds the bony skull. Th ...

, is an unpaired area along the attached margin of the

falx cerebri The falx cerebri (also known as the cerebral falx) is a large, crescent-shaped fold of dura mater that descends vertically into the longitudinal fissure between the cerebral hemispheres of the human brain,Saladin K. "Anatomy & Physiology: The Uni ...

. It allows blood to drain from the lateral aspects of anterior cerebral hemispheres to the

confluence of sinuses The confluence of sinuses (Latin: confluens sinuum), torcular Herophili, or torcula is the connecting point of the superior sagittal sinus, straight sinus, and occipital sinus. It is below the internal occipital protuberance of the skull. It dr ...

Cerebrospinal fluid Cerebrospinal fluid (CSF) is a clear, colorless body fluid found within the tissue that surrounds the brain and spinal cord of all vertebrates. CSF is produced by specialised ependymal cells in the choroid plexus of the ventricles of the ...

drains through arachnoid granulations into the superior sagittal sinus and is returned to venous circulation.

Structure

Commencing at the foramen cecum, through which it receives emissary veins from the nasal cavity, it runs from anterior to posterior, grooving the inner surface of the

frontal Front may refer to: Arts, entertainment, and media Films * ''The Front'' (1943 film), a 1943 Soviet drama film * ''The Front'', 1976 film Music * The Front (band), an American rock band signed to Columbia Records and active in the 1980s and e ...

, the adjacent margins of the two

parietal lobes The parietal lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The parietal lobe is positioned above the temporal lobe and behind the frontal lobe and central sulcus. The parietal lobe integrates sensory informa ...

, and the superior division of the cruciate eminence of the

occipital lobe The occipital lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The name derives from its position at the back of the head, from the Latin ''ob'', "behind", and ''caput'', "head". The occipital lobe is the vi ...

. Near the

internal occipital protuberance Along the internal surface of the occipital bone, at the point of intersection of the four divisions of the cruciform eminence, is the internal occipital protuberance. Running transversely on either side is a groove for the transverse sinus The ...

, it drains into the

and deviates to either side (usually the right). At this point it is continued as the corresponding

transverse sinus The transverse sinuses (left and right lateral sinuses), within the human head, are two areas beneath the brain which allow blood to drain from the back of the head. They run laterally in a groove along the interior surface of the occipital bone. ...

. The superior sagittal sinus is usually divided into three parts: anterior (foramen cecum to bregma), middle (bregma to lambda), posterior (lambda to confluence).Salunke, P., Sodhi, H. B. S., Aggarwal, A., Ahuja, C. K., Dhandapani, S. S., Chhabra, R., & Gupta, S. K. (2013). Is ligation and division of anterior third of superior sagittal sinus really safe? Clinical Neurology and Neurosurgery, 115(10), 1998–2002. http://doi.org/10.1016/j.clineuro.2013.06.003 It is triangular in section, narrow in front, and gradually increases in size as it passes backward. Its inner surface presents the openings of the

superior cerebral veins The superior cerebral veins, numbering eight to twelve, drain the superior, lateral, and medial surfaces of the hemispheres. They are predominantly found in the sulci between the gyri In neuroanatomy, a gyrus (pl. gyri) is a ridge on the c ...

, which run, for the most part, obliquely forward, and open chiefly at the back part of the sinus, their orifices being concealed by fibrous folds; numerous fibrous bands (chordae Willisii) extend transversely across the inferior angle of the sinus; and, lastly, small openings communicate with irregularly shaped venous spaces (venous lacunae) in the dura mater near the sinus. There are usually three lacunae on either side of the sinus: a small frontal, a large parietal, and an occipital, intermediate in size between the other two. Most of the cerebral veins from the outer surface of the hemisphere open into these lacunæ, and numerous arachnoid granulations (Pacchionian bodies) project into them from below. The superior sagittal sinus receives the

, veins from the diploë and

dura mater In neuroanatomy, dura mater is a thick membrane made of dense irregular connective tissue that surrounds the brain and spinal cord. It is the outermost of the three layers of membrane called the meninges that protect the central nervous system. ...

, and, near the posterior extremity of the sagittal suture, veins from the

pericranium The periosteum is a membrane that covers the outer surface of all bones, except at the articular surfaces (i.e. the parts within a joint space) of long bones. Endosteum lines the inner surface of the medullary cavity of all long bones. Structure ...

, which pass through the

parietal foramina A parietal foramen is an opening in the skull for the parietal emissary vein, which drains into the superior sagittal sinus. Occasionally, a small branch of the occipital artery can also pass through it. It is located at the back part of the parie ...

Function

drains through arachnoid granulations into the superior sagittal sinus and is returned to venous circulation.

Additional images

File:Sobo 1909 590.png, Brain with sagittal sinus at centre, with various lacunae. File:Gray133.png, Left parietal bone. Inner surface. File:Gray135.png, Frontal bone. Inner surface. File:Gray193.png, Base of the skull. Upper surface. File:Gray769.png, Diagrammatic representation of a section across the top of the skull, showing the membranes of the brain, etc. File:Gray1196.png, Diagrammatic section of scalp. File:Human brain dura mater description.JPG, Human brain dura mater File:Slide6Neo.JPG, Meninges and superficial cerebral veins.Deep dissection.Superior view. File:Slide7Neo.JPG, Meninges and superficial cerebral veins.Deep dissection.Superior view.

References

External links

* http://neuroangio.org/venous-brain-anatomy/venous-sinuses/ {{Authority control Veins of the head and neck

Structure

Function

Additional images

See also

References

External links