Emissary Veins

Question 1

Definition

Answer 1

Valveless veins connecting Dural sinuses (inside skull) with veins in scalp and face (outside skull) passing through emissary foramina in skull

Question 2

Function

Answer 2

Equalize venous pressure between Dural sinuses and veins outside skull

Question 3

Clinical importance

Answer 3

They can transmit infection from outside skull to Dural sinuses inside skull causing septic thrombosis of sinuses as cavernous sinus thrombosis

Question 4

Site and distribution

Answer 4

1. Veins connected to Superior sagittal sinus
2. Veins connected to cavernous sinus
3. Veins connected to sigmoid sinus

Question 5

Veins connected to superior sagittal sinus (2)

Answer 5

1. Vein through foramen caecum: connects with veins of nose
2. Vein through parietal emissary foramen: connect with scalp occipital vein

Question 6

Veins connected to cavernous sinus (3)

Answer 6

1. Vein through foramen ovale: connect with pterygoid venous plexus
2. Veins through foramen lacerum: connect with pterygoid and pharyngeal venous plexuses
3. Vein through carotid canal: connect with pharyngeal venous plexus or with IJV

Question 7

Veins connected to sigmoid sinus

Answer 7

1. Vein through mastoid foramen: connect with occipital veins
2. Vein through posterior posterior condylar foramen: connect suboccipital venous plexus
3. Vein through hypoglossal canal: connect with IJV