Flashcards in Session 3 - Major Blood Vessels of the Head and Neck Deck (43):
Where does the external jugular vein run in relation to the sternocleidomastoid?
The external jugular vein runs over the top of the sternocleidomastoid.
What does the brachiocephalic trunk bifurcate into?
Common carotid artery
The vertebral, internal thoracic and thyrocervical arteries all arise from which blood vessel?
What blood vessels does the common carotid artery bifurcate into?
Internal and external carotid arteries
What are the branches of the thyrocervical trunk?
Inferior thyroid artery
Ascending cervical artery
Transverse cervical artery
Describe the route of the vertebral arteries.
Arise from the subclavian arteries.
Ascend in the neck through the transverse foramina of cervical vertebrae 6-1.
Pass through the foramen magnum.
Supply the brain.
Does the internal carotid artery give off any branches in the neck?
Describe the location of the internal jugular vein in relation to the common carotid artery and sternocleidomastoid.
The internal jugular vein lies laterally to the common carotid artery. Both run under the sternocleidomastoid.
At what level does the common carotid artery bifurcate?
At about the level of the superior border of the thyroid cartilage. C3-C4.
The bifurcation of the common carotid artery is a common site for the formation of what?
What is the carotid sinus?
A dilation of the internal carotid artery at the region of the bifurcation of the common carotid artery. It is the location of baroreceptors for detecting changes in arterial blood pressure.
What is the carotid body?
A cluster of chemoreceptors and supporting cells located near the bifurcation of the common carotid artery. Mainly detect changes in the partial pressure of oxygen, but are also sensitive to changes in carbon dioxide, pH and temperature.
What are the borders of the carotid triangle?
Superior - posterior belly of the digastric muscle
Lateral - medial border of sternocleidomastoid
Inferior - superior belly of the omohyoid muscle
What are the main contents of the carotid triangle?
Common carotid artery (bifurcate in carotid triangle)
Internal jugular vein
What can carotid sinus massage be used to treat?
Stimulates vagus input to the heart by activating baroreceptors in the carotid sinus. This causes a drop in heart rate.
Describe the route of the internal carotid artery.
Arises from the common carotid artery, runs up the neck.
Enters the skull through the carotid canal in the petrous part of the temporal bone.
Turns medially and horizontally.
Enters the cranial cavity and then makes a S-shaped bend.
Courses through the cavernous sinus.
What structures run through the cavernous sinus?
Internal carotid artery
CN III - oculomotor
CN IV - trochlear
CN Va - opthalmic
CN Vb - maxillary
Plexus of extremely thin walled veins on the upper surface of the sphenoid bone.
The opthalmic artery is a branch of what artery?
Internal carotid artery
The supratrochlear and supraorbital arteries arise from what artery?
Name the branches of the external carotid artery. Which of these branches are terminal branches?
Superior thyroid artery
Ascending pharyngeal artery
Posterior auricular artery
Superficial temporal artery (terminal)
Maxillary artery (terminal)
Name the arteries supplying the scalp. Which arteries arise from the internal carotid artery and which arteries arise from the external carotid artery?
Arising from the internal carotid (via opthalmic artery):
Arising from external carotid:
Superficial temporal artery
Posterior auricular artery
Blood vessels of the scalp lie in what layer?
Subcutaneous connective tissue layer (dense connective tissue)
What is the main blood vessel supplying the skull?
Middle meningeal artery
Why do scalp wounds bleed profusely?
Walls of the arteries are closely attached to the connective tissue, limiting constriction.
Numerous anastomoses - profuse bleeding.
Explain why loss of scalp does not lead to bone necrosis.
Blood supply to the skull is mostly through the middle meningeal artery, it is not supplied by arteries of the scalp.
Name the superficial arteries of the face.
Transverse facial artery
Lateral nasal artery
Superior labial artery
Inferior labial artery
Where can the pulse of the facial artery be palpated?
Inferior border of the mandible, anterior to the masseter muscle.
The middle meningeal artery supplies what structures?
Skull and dura
The middle meningeal artery is a branch of which artery?
What is Kiesselbach’s area?
Region in the anteroinferior part of the nasal septum containing Kiesselbach’s plexus.
What four arteries anastomose to form Kiesselbach’s plexus?
Anterior ethmoidal artery (branch of opthalmic artery)
Sphenopalatine artery (branch of maxillary artery)
Greater palatine artery (branch of maxillary artery)
Septal branch of the superior labial artery (branch of artery)
The Kiesselbach’s area is a common site for what, especially in young children?
Epistaxis (nose bleed)
Rupture of the middle meningeal artery will lead to what sort of haemorrhage?
In a craniotomy, why is the bone and scalp flap reflected inferiorly?
To preserve the blood supply
Where do the supraorbital and supratrochlear veins unite, what vein do they form and what vein does it drain into?
Supraorbital and supratrochlear veins unite at the medial angle of the eye to form the angular vein which drains into the facial vein.
What veins connect venous drainage of the scalp to dural venous sinuses?
Do veins of the face have valves?
Deep facial veins drain into what plexus?
Pterygoid venous plexus
What is the danger triangle of the face?
Area of the face where infections can spread from the face through the venous system to dural venous sinuses.
Name all the main dural venous sinuses.
Superior sagittal sinus
Inferior sagittal sinus
The sigmoid sinuses drain into what veins?
Internal jugular veins
What vein is used to measure jugular venous pressure? Why?
Right internal jugular vein. Effectively like a direct connection to the right atrium, so better indication of pressure in the right atrium.