Dural venous sinuses

Sagittal sinuses

Straight sinus

Each anterior cerebral vein leaves the longitudinal cerebral fissure inferiorly and crosses the optic chiasm ventrally to join the respective deep middle cerebral (which coursed medially through the lateral sulcus of Sylvius). Together, these vessels form the basal vein of Rosenthal that also receives tributaries from the anterior pontomesencephalic (draining from the anterior pons), lateral mesencephalic veins (from the superior pons) and branches from the superior colliculi.

The paired internal cerebral veins (formed from the thalamostriate and choroidal veins) merge with the basal vein of Rosenthal, the posterior mesencephalic veins and the dorsal vein of corpus callosum to form the great cerebral vein of Galen at the end of the splenium of corpus callosum. The great cerebral vein of Galen then drains to the straight sinus. The straight sinus is a midline structure that lies within the posterior end of the falx cerebri and the middle of the tentorium cerebelli. It also terminates at the level of the internal occipital protuberance.

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Sphenoparietal sinuses

The sphenoparietal sinus courses along the free border of the lesser wing of the sphenoid bone. It follows the groove of the bone and drains into the cavernous sinus after receiving a tributary on either side from the superficial middle cerebral vein. The superficial middle cerebral vein communicates with the superior cerebral veins via the superior anastomotic vein of Trolard. It therefore aids in draining blood from the cerebral hemispheres as well as the optic part of the frontal lobe.

Cavernous sinuses

In addition to receiving tributaries from the sphenoparietal sinus, the cavernous sinus also receives tributaries from the superior and inferior ophthalmic veins, and efferent hypophyseal veins. This pair of sinuses, also called the parasellar sinuses, is located on either side of the sella turcica of the sphenoid bone. Their cavities have a spongy appearance that is formed by the numerous vessels passing through it.

In addition to acting as a conduit for blood, the cavernous sinus also facilitates the passage of the: 

• CN III (oculomotor)
• CN IV (trochlear)
• CN V1 (ophthalmic division of trigeminal)
• CN V2 (maxillary division of trigeminal)
• CN VI (abducent)
• cavernous part of the internal carotid artery

The cavernous sinus is the only one of the paired dural sinuses that communicates with each other. These sinuses have two intercavernous branches arching over the diaphragma sellae of the pituitary gland; one anterior and the other posterior to the infundibulum. They drain posteriorly by the petrosal sinuses.

Petrosal sinuses

Occipital sinus

Coursing through the fixed part of the falx cerebelli toward the internal occipital protuberance, from the edge of the foramen magnum, is the occipital sinus.

Transverse sinuses

The left and right transverse sinuses travel in the base of the tentorium cerebelli, along the occipital bone. It communicates with the straight sinus, superior sagittal sinus and the occipital sinus at a point called the confluence of sinuses; at the level of the internal occipital protuberance. The sinus also receives venous contributions from the inferior cerebral vein and the inferior anastomotic vein of Labbé, which communicates with the vein of Trolard and the superficial middle cerebral vein.

To quickly remember the tributaries to the confluence of sinuses you can use the mnemonic "TOSS" (Transverse sinus, Occipital sinus, Superior sagittal sinus, Straight sinus).

For more details about the dural venous sinuses, take a look at the videos, illustrations. and quizzes included in the following study unit:

Sigmoid sinus

Finally, the sigmoid sinuses are a paired, bilateral, s-shaped set of sinuses that course along the floor of the posterior cranial fossa. They are the terminal parts of the dural venous sinuses that continue from the transverse sinuses at the level of the tentorium cerebelli. Just after the sigmoid sinus receives the inferior petrosal sinus, it forms a jugular bulb that enters the jugular foramen with CN IX (glossopharyngeal), CN X (vagus) and CN XI (accessory) as the internal jugular vein.