Occipital Sinus

The occipital sinus (lat. sinus occipitals) is one of the paired formations of the posterior cranial fossa, an arcuate fissure that opens back into the foramen magnum, and from above into the superior occipital groove.

**Topography.** The occipital sinus is located at the posterior edge of the foramen magnum and has the appearance of a horizontally running fissure. The external carotid artery enters it in front, and the vertebral arterial cone emerging from it from behind, which also participates in the formation of the sinus. The posterior cerebral arteries, carrying blood from the lateral parts of the cranial cavity, exit into the abducens, posterior rectus and temporo-parietal regions.