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 Groove or Grooves may refer to: Music * Groove (music) * Groove (drumming) * The Groove (band), an Australian rock/pop band of the 1960s * The Groove (Sirius XM), a US radio station * Groove 101.7FM, a former Perth, Australia, radio station ...

along the interior surface of the

occipital bone The occipital bone () is a cranial dermal bone and the main bone of the occiput (back and lower part of the skull). It is trapezoidal in shape and curved on itself like a shallow dish. The occipital bone overlies the occipital lobes of the cer ...

. They drain from 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 drai ...

(by 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 ...

) to the sigmoid sinuses, which ultimately connect to the

internal jugular vein The internal jugular vein is a paired jugular vein that collects blood from the brain and the superficial parts of the face and neck. This vein runs in the carotid sheath with the common carotid artery and vagus nerve. It begins in the poste ...

. ''See diagram (at right)'': labeled under the brain as "" (for Latin: ''sinus transversus'').

Structure

The transverse sinuses are of large size and begin at the

; one, generally the right, being the direct continuation of the superior sagittal sinus, the other of the straight sinus. Each transverse sinus passes lateral and forward, describing a slight curve with its convexity upward, to the base of the petrous portion of the

temporal bone The temporal bones are situated at the sides and base of the skull, and lateral to the temporal lobes of the cerebral cortex. The temporal bones are overlaid by the sides of the head known as the temples, and house the structures of the ears. ...

, and lies, in this part of its course, in the attached margin of the

tentorium cerebelli The cerebellar tentorium or tentorium cerebelli ( Latin for "tent of the cerebellum") is an extension of the dura mater that separates the cerebellum from the inferior portion of the occipital lobes. Structure The cerebellar tentorium is an arc ...

; it then leaves the tentorium and curves downward and medialward (an area sometimes referred to as the

sigmoid sinus The sigmoid sinuses (sigma- or s-shaped hollow curve), also known as the , are venous sinuses within the skull that receive blood from posterior dural venous sinus veins. Structure The sigmoid sinus is a dural venous sinus situated within the ...

) to reach the

jugular foramen A jugular foramen is one of the two (left and right) large foramina (openings) in the base of the skull, located behind the carotid canal. It is formed by the temporal bone and the occipital bone. It allows many structures to pass, including the ...

, where it ends in the

. In its course it rests upon the squama of the occipital, the

mastoid angle The mastoid part of the temporal bone is the posterior (back) part of the temporal bone, one of the bones of the skull. Its rough surface gives attachment to various muscles (via tendons) and it has openings for blood vessels. From its borders, ...

of the parietal, the mastoid part of the temporal, and, just before its termination, the

jugular process The jugular process is a quadrilateral or triangular bony plate projecting lateralward from the posterior half of the occipital condyle; it is a part of the lateral part of the occipital bone. The jugular process is excavated in front by the jugu ...

of the occipital; the portion which occupies the groove on the mastoid part of the temporal is sometimes termed the

. The transverse sinuses are frequently of unequal size, with the one formed by the superior sagittal sinus being the larger; they increase in size as they proceed, from back to center. On transverse section, the horizontal portion exhibits a prismatic form, the curved portion has a semicylindrical form. They receive the blood from the superior petrosal sinuses at the base of the petrous portion of the temporal bone; they communicate with the veins of the pericranium by means of the

mastoid The mastoid part of the temporal bone is the posterior (back) part of the temporal bone, one of the bones of the skull. Its rough surface gives attachment to various muscles (via tendons) and it has openings for blood vessels. From its borders, ...

and condyloid

emissary vein The emissary veins connect the extracranial venous system with the intracranial venous sinuses. They connect the veins outside the cranium to the venous sinuses inside the cranium. They drain from the scalp, through the skull, into the larger men ...

s; and they receive some of the

inferior cerebral The inferior cerebral veins are veins that drain the undersurface of the cerebral hemispheres and empty into the cavernous and transverse sinuses. Those on the orbital surface of the frontal lobe join the superior cerebral veins, and through these ...

and

inferior cerebellar vein The cerebellar veins are veins which drain the cerebellum. They consist of the superior cerebellar veins and the inferior cerebellar veins (dorsal cerebellar veins). The superior cerebellar veins drain to the straight sinus and the internal cereb ...

s, and some veins from the

diploë Diploë ( or ) is the spongy cancellous bone separating the inner and outer layers of the cortical bone of the skull. In the cranial bones, the layers of compact cortical tissue are familiarly known as the tables of the skull; the outer one ...

. The

petrosquamous sinus The petrosquamous sinus is a fetal vein that generally disappears by birth and, when present, runs backward along the junction of the squama and petrous portion of the temporal, and opens into the transverse sinus The transverse sinuses (lef ...

, when present, runs backward along the junction of the squama and petrous portion of the temporal, and opens into the transverse sinus.

Additional images

File:Gray133.png, Left parietal bone. Inner surface. File:Gray567.png, Dura mater and its processes exposed by removing part of the right half of the skull, and the brain File:Gray570.png, The sinuses at the base of the skull File:Gray908.png, Horizontal section through left ear; upper half of section File:Gray1198.png, Relations of the brain and middle meningeal artery to the surface of the skull File:Gray1209.png, Left temporal bone showing surface markings for the tympanic antrum (red), transverse sinus (blue), and facial nerve (yellow) File:Transverse sinus 2.jpg, Transverse sinuses File:Transverse sinuses 2.jpg, Transverse sinuses

References

External links

Cerebral Venous Sinuses
at neuroangio.org {{Authority control Veins of the head and neck

Structure

Additional images

See also

References

External links