Pathway of External & Internal Jugular Veins

(hey guys..and girls..erm, reli reli sori for not being able to b there at the prac today..sori!!! here's my part..hope it helps..)

External Jugular Veins
- begins near the angle of the mandible
- union of posterior auricular vein and retromandibular vein
(*revision: retromandibular vein is formed when superficial temporal vein meets maxillary vein)
- crosses SCM obliquely and deep to the platysma
enters the anteroinferior part of the lateral cervical region
pierce the investing layer of deep cervical fascia (posterior of SCM)
- terminates in the subclavian vein

Internal Jugular Veins
- starts at the jugular foramen, a continuation of the sigmoid sinus
the dilated area at the start of the IJV at the jugular foramen is called superior bulb of the IJV
- descends in the carotid sheath with:

• superior to the carotid bifurcation - internal carotid artery
• inferior to the carotid bifurcation - common carotid artery & vagus nerve

- passes throught the anterior cervical region
passes deep to the SCM
passes deep to the gap between the sternal and clavicular head of SCM
- terminates posterior to the sternal end of the clavicle where it merges with the subclavian vein to form the brachiocephalic vein
dilates at the end to form the inferior bulb of the IJV (important because the inferior bulb has a bicuspid valve which permits blood flow to the heart while preventing backflow of blood into the vein)

(Posted by: Vivian)