Major BLood Vessels of the Head and Neck Flashcards
What major vessel is superficial to the sternocleidomastoid?
External jugular vein
What arteries arise from the arch of the aorta?
Brachiocephalic trunk on right - gives off
common carotid and subclavian artery
Then the common carotid and subclavian on the left.
What branches does the common carotid artery give off in the neck?
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What does the common artery give off when it bifurcates?
External and Internal arteries
What branches does the subclavian artery give off?
Vertebral artery
Internal thoracic artery
Thyrocervical artery
What branches does the thyrocervical artery give off?
And what do they supply?
Suprascapular artery - supplies shoulder
Transverse cervical artery - supplies the neck
Ascending cervical artery - supplies the neck
Inferior thyroid artery - supplies the lower pole of the thyroid gland
Describe the vertebral arteries - where they arise, their route and what they supply.
They arise from the subclavian arteries on the left and right
They ascend in the neck through the transverse foramina in cervical vertebrae 6-1
They supply the brain
Describe the internal carotid artery - where it arises, branches and entrance into skull
It arises from the bifurcation of the common carotid artery
It gives off no branches in the neck
Enters Skull through carotid canal
Where does the common carotid artery bifurcate?
At about the level of the superior border of the thyroid cartilage
What is the carotid sinus?
A swelling at the region of the bifurcation
The location of baroreceptors for detecting changes in arterial BP.
What is the carotid body?
Found at the bifurcation of the carotid artery
It has lots of peripheral chemoreceptors which detect arterial pO2.
Bifurcation of the common carotid artery is a common site for what?
Atheroma formation
Why is an atheroma formation dangerous at the bifurcation of the common carotid artery?
Rupture of the clot can cause an embolus to travel to the brain and can cause a TIA or stroke
What lies within the carotid sheath?
Common carotid artery
Internal jugular vein
Vagus nerve
Deep cervical lymph nodes
What are the borders of the carotid triangle?
Superior - posterior belly of digastric
Lateral - sternocleidomastoid
Medial - superior belly of omohyoid
What is inside the carotid triangle?
Internal jugular vein
Bifurcation of the common carotid artery
-external and internal carotid artery
Why is the carotid triangle useful clinically?
Important for surgical approach to the carotid arteries or internal jugular vein
Can also access the vagus and hypoglossal nerves
Carotid pulse can be felt
Carotid sinus massage
What are the branches of the external carotid artery?
Superior thyroid Lingual Facial Ascending pharyngeal Occipital Posterior auricular
Terminal branches
- Superficial temporal
- Maxillary
Describe the blood supply to the scalp
Lots of anastomoses
5 arteries:
- Supra-orbital artery \\ these are branches of the
- Supratrochlear artery /// internal carotid artery
- Superficial temporal artery \ \ \ these are branches
- Posterior auricular artery »_space;> of the
- Occipital artery / / / external carotid artery
Name the layers of the scalp
Skin Connective tissue (dense) Aponeurosis Loose connective tissue Periosteum
(Vessels of the scalp lie in the subcutaneous connective tissue layer)
What is the clinical relevance of the blood supply to the scalp?
Walls of the arteries are closely associated with the connective tissue, so it limits the constriction of arteries and can result in profuse bleeding
Numerous anastomoses - profuse bleeding
Deep lacerations involving the cranial Aponeurosis cause profuse bleeding as it is attached to two muscles either side that will pull it apart when lacerated
Loss of scalp blood supply does not mean bone necrosis.
What generally accompanies the arteries of the scalp?
Superficial veins
- Superficial temporal veins
- Occipital veins
- Posterior auricular veins
Where do the supraorbital and supratrochlear veins meet and where do they drain to?
They unite at the medial angle of the eye to form the angular vein, which drains into the facial vein
Where do some deep parts of the scalp drain into?
In the temporal region some of the veins drain into the pterygoid venous plexus.
How do the veins of the scalp connect to the diploic veins of the skull?
And what is the clinical relevance of this?
Through several emissary veins
This is relevant because they therefore connect to dural venous sinuses
And emissary veins are valve less.
And so infection can spread from the scalp to the cranial cavity and effect the meninges
What is the main artery that supplies the dura and skull?
And where does it arise from?
The middle meningeal artery, which is a branch of the maxillary artery
What does the middle meningeal artery branch into?
The posterior branch and the anterior branch of the middle meningeal artery.
What is the clinical relevance of the route of the anterior branch of the middle meningeal artery?
It runs close to the Pterion, which is connection of 4 bones of the skull and is thinner there than usual
And so it is easier to break at the pterion which could lead to damage to the anterior branch of the middle meningeal artery and cause an extradural haemorrhage
What is a craniotomy?
And how is performed to preserve blood supply?
An operation to gain access to the brain
When cutting away the bone and Scalp, reflect it inferiorly to preserve blood supply.
What are the branches of the facial nerve?
And where are they located?
Superior and inferior labial artery - located above and below the lip
Angular artery - the angle of the eye
Lateral nasal artery - On the nose
Which arteries supply the superficial areas of the face?
And which artery supplies the deep areas of the face?
The facial artery and superficial temporal arteries are the main suppliers of the superficial face
The maxillary artery is the main supplier to the deep parts of the face.
Where can the facial artery pulse be felt
At the inferior border of the mandible, anterior to the masseter muscle
What are dural venous sinuses?
Endothelium lined spaces between periosteal and meningeal layers of dura
They receive blood from the large veins draining the brain
Name the dural venous sinuses
Superior sagittal sinus Inferior sagittal; sinus Cavernous sinus Sigmoid sinus Transverse sinus
Describe the venous drainage of the face
Superficial veins are: -Supra-orbital -Supratrochlear -Angular vein -Superior and inferior labial veins -Facial vein -Common facial vein -Internal jugular vein And they drain in that order
Describe the cavernous sinus and the contents of the cavernous sinus
A plexus of extremely thin-walled veins on upper surface of sphenoid
Also in cavernous sinus:
- Internal carotid artery
- CNIII oculomotor
- CNIV trochlear
- CNVI abducent
- 2 branches of trigeminal
- Also has the pituitary gland
What is the clinical relevance of the cavernous sinus?
The facial veins communicate with the cavernous sinus, and if you get an infection in the face, if in the right area it can move into the cavernous sinus and cause other problems including damage to the nerves present.
What vein is the best indication of right atrial pressure?
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