2.1 Major Blood Vessels of the Head and Neck Flashcards
What muscle covers blood vessels? What is the exception?
The SCM covers most blood vessels, apart from external jugular vein
Describe the location of the EJV vs IJV in relation to the SCM?
External jugular vein runs along the outside of the SCM, can be seen
Internal Jugular vein is located underneath the SCM, not visible
Describe the relation of the CCA and Vagus Nerve to the IJV
CCA is medial to the Internal Jugular vein
Vagus nerve runs behind it
Label the image below
Where does most of the blood supply to the head and neck come from?
How does this artery divide and what speciifc structures do these supply?
Most of blood supply comes from carotid artery
Divides into
- Internal carotid – brain (with vertebral artery)
- External carotid – face, scalp, skull
What is the blood supply to the scalp?
The ECA and 2 small branches of ICA - supratrochlear and supraorbital
What artery supplies the face?
What is this a branch of?
Facial artery - branch of the ECA
What veins drain into the cavernous sinus and pterygoid plexus?
What is the clinical importance?
Some deep facial and scalp veins - potential route of infection
What 3 branches does the Subclavian artery gives off in the neck?
1) Vertebral a.
2) Thyrocervical a.
3) Internal Thoracic a
What do the vertebral arteries arise from?
Through what structure do they ascend through neck?
Arise of the subclavian arteries on L and R
Ascend in the neck through transverse foramina in cervical vertebrae 6-5-4-3-2-1
What 2 arteries supply the brain?
The Vertebral arteries and Internal carotid arteries
Through what structure does the ICA enter the skull?
Enters skull through carotid canal
What are the 4 major branches of the Thyrocervical Trunk?
1) Suprascapular a.
2) Transverse Cervical
3) Inferior Thyroid
4) Ascending Cervical
What artery supplies the Thyroid?
What does this arise from?
Inferior Thyroid a.
Arises from the Thyrocervical Trunk
At what anatomical location does the CCA bifurcate?
Around the level of the superior border of the thyroid cartilage
What 2 arteries have NO branches in the neck?
The CCA and the ICA
What are the boarders of the carotid triangle?
Superior: digastric (posterior belly) and stylohyoid
Lateral: medial border of SCM
Inferior: superior belly of omohyoid muscle
What are the contents of the carotid triangle?
IJV and bifurcation of CCA
What vein, artery and nerves can be accessed in the carotid triangle?
IJV, CCA, Vagus n. and Hypoglossal n.
Where can the carotid pulse be felt?
In carotid triangle (may also be palpated more inferiorly)
What can be done to a patient with SVT and why?
Carotid sinus massage.
Massaging this area stimulates CN IX (glossopharyngeal n.)
This goes to brain and stimulatess Vagus nerve (CN X) to slow down HR
Where is the carotid sinus located?
What important structures are found here?
Swelling located on the ICA at the region of bifurcation
Location of baroreceptors for detecting changes in arterial BP
Where is the carotid body located?
What important structures are found here?
Located at the bifurcation
Peripheral chemoreceptors which detect arterial O2
Bifurcation of the carotid artery is a common site for what?
Describe what this can lead to
Atheroma formation
Plaque causes narrowing (stenosis) of the artery
Rupture of the fatty deposit can cause an embolus to travel to brain resulting in a TIA or stroke
How many carotid sheaths do we have?
What forms the sheaths?
What is contained in each?
2 carotid sheaths, formed by contributions from investing, prevertebral, and pretracheal layers
Each contains: CCA, ICA, IJV, Vagus n. (ECA leaves sheath at bifurcation)