Dural venous sinuses, Ankur Saxena

Human Cranial, Dural, Venous Sinuses, Undergraduate medical students

1. Dural Venous Sinuses

2. Venous channels situated between inner & outer layers of Dura mater D rain the venous blood of the brain & bones of the skull. T ransmit the venous blood to the internal jugular vein. Communicates with the internal vertebral venous plexus through the foramen magnum Also communicates with the scalp veins through the emissary veins Valveless

3. The D ural sinuses maybe divided into 2 groups 1- single: S uperior saggital , I nferior saggital & Occipital 2- Paired: Spheno-parietal , Cavernous , Superior petrosal , Inferior petrosal & Sigmoid.

4. 1- Superior sagittal sinus Attachments. B egins in front at the frontal crest & ends behind at the internal occipital protuberance The superior sagittal sinus receives the following : 1- Superior cerebral veins 2- dipolic veins 3- Emissary veins 4- arachnoid granulation 5- meningeal veins

5. 2 – Inferior sagittal sinus It occupies the posterior 1/2 or 2/3 of the lower free border of falx cerebri . It ends posteriorly by joining the straight sinus It receives cerebral veins from the medial surface of the cerebral hemisphere

6. 3- Straight sinus It lies at the junction of the falx cerebri and tentorium cerebelli It receives : 1- inferior sagital sinus 2- great cerebral vein It ends at internal occipital protuberance by becoming the left transverse sinus

7. 4- Transverse sinus Paired sinus It extends horizontally in the attached border of tentorium cereblli. The right sinus receive the superior sagittal sinus however ,the left sinus receive the inferior sagittal sinus Each sinus end by becoming continuous with sigmoid sinus Transverse sinus receive the following tributaries : 1- Superior petrosal sinus 2- cerebellar veins 3- Occipital diploic vein.

8. 5- occipital sinus It is the smallest dural sinus & is situated in the attached margin of the falx cerebelli It continuates with the internal vertebral plexus

9. 6 - S pheno-parietal sinus paired sinus It lies on the edge of the lesser wing of sphenoid 7- superior petrosal sinus It is a paired sinus situated on the upper border of the petrous bone It lies at the attachment border of tentorium cerebelli It continues with cavernous sinus anteriorly & with transverse sinus posteriorly.

10. 8- Inferior petrosal sinus It is a paired sinus situated between the petrous bone & basilar part of occipital bone It communicates with cavernous sinus anterior & with superior bulb of internal jugular vein posterior

11. 9- Cavernous sinus Position : it lies on the side of the body of sphenoid Relation: A- Medially Sphenoid air sinus Pituitary gland B- Laterally Trigeminal ganglion Uncus of temporal lobe C- Nerves in its lateral wall 3 RD cranial nerve 4 th cranial nerve Ophthalmic division of 5 th cranial nerve maxillary division of 5 th cranial nerve D- Structures within its cavity Internal carotid artery Abducent nerve

12. Tributaries of cavernous sinus : A- Anteriorly 1- Ophthalmic vein 2- Spheno-parietal sinus   B- Posterior ly Superior petrosal sinus Inferior petrosal sinus   C- Medially Anterior & posterior intercavernous sinuses  

13. D- Superior Superficial middle cerebral vein Veins from inferior surface of brain E- Inferior Emissary vein through the carotid canal which connects the sinus with internal jugular vein Emissary vein through the foramen ovale which connects the sinus with pterygoid venous plexus

14. The cavernous sinus communicates with the veins of the face through 2 routes : Superior ophthalmic veins, Deep facial vein, pterygoid plexus of veins & emissary vein through the foramen Ovale.  

15. 10- Sigmoid sinus It is wide S- shaped sinus which begins at the lateral & of transverse sinus . The sinus ends by passing through the jugular foramen where it becomes continues with internal jugular vein It has the following tributaries Posterior condylar emissary vein Mastoid emissary vein

16. Applied Anatomy : Cavernous Sinus Thrombosis. Meningioma.