Superior sagittal sinus
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| Vein: Superior sagittal sinus | ||
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| Dural veins (Superior sagittal sinus labeled as "SIN. SAGITALLIS SUP." at top.) | ||
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| Superior sagittal sinus laid open after removal of the skull cap. The chordæ Willisii are clearly seen. The venous lacunæ are also well shown; from two of them probes are passed into the superior sagittal sinus. | ||
| Latin | sinus sagittalis superior | |
| Gray's | subject #171 654 | |
| MeSH | A07.231.908.224 | |
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 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.
[edit] Details from Gray's anatomy
The superior sagittal sinus (superior longitudinal sinus) occupies the attached or convex margin of the falx cerebri.
Commencing at the foramen cecum, through which it receives a vein from the nasal cavity, it runs from before backward, grooving the inner surface of the frontal, the adjacent margins of the two parietals, and the superior division of the cruciate eminence of the occipital; near the internal occipital protuberance it deviates to one or other side (usually the right), and is continued as the corresponding transverse sinus.
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, 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 (chordæ Willisii) extend transversely across the inferior angle of the sinus; and, lastly, small openings communicate with irregularly shaped venous spaces (venous lacunæ) in the dura mater near the sinus.
There are usually three lacunæ 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 superior cerebral veins, veins from the diploë and dura mater, and, near the posterior extremity of the sagittal suture, veins from the pericranium, which pass through the parietal foramina.
[edit] See also
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.
