Dural venous sinuses

  • Collectors that drain the veins of the brain away towards the internal jugular veins
  • Within the dura mater
  • Two physiological blood streams
    • Superior blood stream (vault) :superior sagittal sinus, inferior sagittal sinus and straight sinus
    • Inferior blood stream (basis)

Superior sagittal sinus

  • Median
  • Within the superior edge of the falx cerebri, along its full length
  • Large diameter, increasing from front to back
    → transverse sinuses, via the confluence of sinuses

Inferior sagittal sinus

  • Median
  • Small diameter
  • within the posterior two thirds of the inferior edge of the falx cerebri
  • → straight sinus

Straight sinus

Occipital sinus

  • Median
  • Arises from the small veins around the foramen magnum
  • Within the posterior edge of the falx cerebelli
  • → transverse sinuses, via the confluence of sinuses

Transverse sinus

  • Within the posterior edge of the tentorium cerebelli to the basis of the petrous part of the temporal bone
  • → sigmoid sinus

Sphenoparietal sinus

  • Along the posterior edge of the lesser wing of sphenoid bone
  • → cavernous sinus

Anterior and posterior intercavernous sinuses

Cavernous sinus

  • Short and large
  • Lateral to the sella turcica, from the superior orbital fissure to the apex of the petrous part of the temporal bone
  • Crossed by:
  • Contains within its lateral wall:
    • Oculomotor nerve (III)
    • Trochlear nerve (IV)
    • Ophtalmic branch of trigeminal nerve (V1)
  • → inferior and superior petrosal sinuses

Superior petrosal sinus

  • Within the posterior edge of the tentorium cerebelli, along the superior edge of the petrous part of the temporal bone
  • → sigmoid sinus

Sigmoid sinus

  • On the inside surface of the mastoid process
  • Tortuous path
  • Continues into the internal jugular vein at the level of the jugular foramen

Basilar plexus

  • On the basilar part of the occipital bone
  • Between the inferior petrosal sinuses

Inferior petrosal sinus

  • At the junction between the petrous part of the temporal bone and the basilar part of the occipital bone
  • Joins the internal jugular vein where the sigmoid sinus forms the internal jugular vein, at the level of the jugular foramen