The cavernous sinus (Latin: sinus cavernosus) is a large, paired channel filled with venous blood that is located against the lateral aspect of the body of the sphenoid bone on each side of the sella turcica.
The cavernous sinus extends from the medial end of the superior orbital fissure to the apex of the petrous temporal bone and drains into the superior petrosal sinus, and the inferior petrosal sinus.
The cavernous sinus receives venous blood from the following vessels:
- superior ophthalmic vein,
- inferior ophthalmic veins,
- basilar plexus,
- superficial middle cerebral vein,
- inferior cerebral vein,
- sphenoparietal sinus.
And occasionally from:
- central retinal vein,
- frontal tributary of the middle meningeal vein.
The cavernous sinus accommodates the internal carotid artery, and transmits several cranial nerves to the superior orbital fissure and to the foramen rotundum. These are the oculomotor, trochlear, abducens nerves, as well as the ophthalmic and maxillary divisions of the trigeminal nerve. The internal carotid artery and the abducens nerve lie medially in the cavernous sinus, but the oculomotor, trochlear, ophthalmic and maxillary nerves are located within the lateral wall of the sinus.