Cavernous Sinus: Relations and Laboratory Identifications

Boundaries

1. anterior: superior orbital fissure
2. posterior: apex of the petrous portion of temporal bone (region of the lacerate foramen)
3. superior: diaphragma sellae
4. inferior: greater wing of sphenoid bone lateral to sella turcica and medial to foramen ovale
5. medial: sella turcica (sphenoid sinus, carotid groove)
6. lateral: separation of meningeal dura from periosteal dura near foramen ovale

Related Bony Landmarks

1. lacerate foramen - transmits emissary v. between cavernous sinus and pterygoid venus plexus
2. pterygoid canal - anterior lip of lacerate foramen
3. sella turcica - dorsum sellae, hypophyseal fossa (for the hypophysis), tuberculum sellae
4. anterior clinoid processes - lateral to path of internal carotid a., support diaphragma sellae
5. chiasmatic groove - marks location of optic chiasm, anterior boundary of middle cranial fossa
6. posterior clinoid processes - support diaphragma sellae
7. trigeminal cave - region marking location of trigeminal ganglion
8. foramen rotundum - transmits maxillary from cavernous sinus to pterygopalatine fossa
9. foramen ovale - near, but lateral to cavernous sinus
10. groove for the greater superficial petrosal nerve - leads from canal anterior and medial to cavernous sinus
11. carotid canal - opening into cavernous sinus and lacerate foramen
12. clivus of occipital bone - region of the basilar venus plexus, leads to anterior vertebral venus plexus
13. groove for inferior petrosal sinus - between clivus and petrous portion of temporal bone, inferior petrosal sinus
14. groove for superior petrosal sinus - along superior petrosal ridge of petrous portion temporal bone
15. lesser wing of sphenoid bone - marking location sphenoparietal sinus

Contents

1. oculomotor nerve - superior at level of anterior clinoid process
2. trochlear nerve - related to lateral lip of diaphragma sellae
3. ophthalmic nerve (of V1) - lateral on internal carotid artery
4. abducens nerve - lateral on internal carotid artery
5. maxillary nerve (of V2) - floor of cavernous sinus, lateral on internal carotid artery
6. internal carotid plexus - autonomic plexus on carotid artery
7. greater superficial petrosal nerve - entering cavernous sinus near lacerate foramen and carotid canal
8. deep petrosal nerve - sympathetic motor root derived from internal carotid plexus
9. nerve of the pterygoid canal
10. sympathetic root of ciliary ganglion - hard to find on dissection
11. carotid siphon - internal carotid artery medial in cavernous sinus and lateral to sphenoid sinus (an air sinus)
12. inferior hypophyseal artery

Related Structures

1. diaphragma sellae - contains intercavernous sinus, spread of infection from oposite cavernous sinus
2. hypophysis (pituitary gland) - in hypophyseal fossa
3. sphenoid air sinus
4. superior petrosal sinus - tributary
5. inferior petrosal sinus - tributary
6. basilar venous plexus - on clivus, drains through foramen magnum, anterior internal vertebral venus plexus
7. sphenoparietal sinus - tributary
8. emissary vein through lacerate foramen and foramen ovale from pterygoid venous plexus
9. superior ophthalmic vein - anterior continuation of cavernous sinus