Arteries of head and neck Flashcards
What are the main arteries supplying the head and neck?
Common carotid arteries
Vertebral arteries
What do the common carotid arteries arise from?
Right common carotid artery arises as medial branch from brachiocephalic trunk
Left common carotid artery arises as last branch from aortic arch
Is the right common carotid artery longer or the left common carotid artery? Why?
Left common carotid artery
because it arises directly from the arch of the aorta
What is the surface landmark as to where the brachiocephalic trunk divides into the right common carotid artery?
Right sternoclavicular joint
Where does the common carotid artery travel after it has arisen?
Ascends up the neck
How does the common carotid artery ascend up the neck?
In the carotid sheath
What are the branches of the common carotid artery?
Internal carotid artery
External carotid artery
Where in the neck itself does the common carotid artery bifurcate into the internal and external carotid arteries?
Carotid triangle
At what level does the common carotid artery bifurcate into the internal and external carotid arteries?
C4
Superior margin of thyroid cartilage
Where can the common carotid artery be palpated?
In the carotid triangle just below its bifurcation
Why might palpating a patient’s common carotid artery be avoided?
Carotid sinus baroreceptors may be hypersensitive
may result in bradycardia, hypotension
which would lead to underperfusion of brain, syncope
What is located at the bifurcation of the common artery between the internal and external carotid arteries?
Carotid body
What is the carotid body?
Group of chemoreceptors
What is the function of the carotid body?
Detect changes in partial pressures of oxygen and carbon dioxide in the blood
What is located in the internal carotid artery just after it has arisen?
Carotid sinus
What is the carotid sinus?
Swelling in internal carotid artery just after it has arisen
Contains baroreceptors
What is the clinical significance of the carotid sinus?
Can massage it
to alleviate supraventricular tachycardias
How does massaging the carotid sinus alleviate supraventricular tachycardias?
Increased pressure in carotid sinus
baroreceptor reflex
decreased heart rate
What pathological process occurs at the bifurcation of the common carotid artery into the internal and external carotid arteries as a common site?
Atheroma formation
What are the complications of atheromatous plaques at the bifurcation of the common carotid artery into the internal and external carotid arteries?
Rupture of plaque, clot formation
rupture of clot, embolus
gives transient ischaemic attack or stroke
How can atheromatous plaques at the bifurcation of the common carotid artery into the internal and external carotid arteries be treated?
Carotid end arterectomy
which is where an incision is made into the common carotid artery, and the plaque is physically removed
What are the risks of a carotid end arterectomy?
Damage to internal jugular vein
Damage to vagus nerve, hypoglossal nerve
Where does the internal carotid artery travel in the neck?
Ascends up the neck
How does the internal carotid artery ascend up the neck?
In the carotid sheath
What does the internal carotid artery enter after the neck?
Cranial cavity
How does the internal carotid artery enter the cranial cavity?
Through carotid canal of petrous part of temporal bone
Where does the internal carotid artery travel in the cranial cavity?
Travels antero-medially
then through cavernous sinus
then turns on itself to travel postero-superiorly
What does the internal carotid artery do in the cranial cavity?
Gives off branches
What is the first branch of the internal carotid artery?
Opthalmic artery
What are some important branches of the ophthalmic artery?
Central retinal artery
Supra-orbital artery
Supra-trochlear artery
Anterior ethmoidal arteries
What is the blood supply of the retina?
Only the central retinal artery
so it is a true anatomical end artery
What is the clinical significance of the central retinal artery being an end artery?
Blockage of this artery gives loss of blood supply to retina, become ischaemic hypoxic
immediate loss of vision on that side
What are the causes of blockage to the central retinal artery? Which is the most common cause?
Thrombus
Embolism, from atherosclerotic plaque in carotid artery - most common cause
Where does the external carotid artery travel in the neck?
Ascends up the neck
How does the external carotid artery ascend up the neck?
Posteriorly to condylar process of the mandible
Anteriorly to the lobule of the ear
What does the external carotid artery do in the neck?
Gives off branches
What branches does the external carotid artery give off in the neck, in the order that they arise?
Superior thyroid artery
Ascending pharyngeal artery
Lingual artery
Facial artery
Occipital artery
Posterior auricular artery
Maxillary artery
Superficial temporal artery
Where does the external carotid artery end?
Parotid gland
How does the external carotid artery end in the parotid gland?
Divides into its terminal branches
the maxillary artery and superficial temporal artery
What does the superior thyroid artery supply?
Superior pole of thyroid gland
What does the ascending pharyngeal artery supply?
Pharynx
What does the lingual artery supply?
The tongue
What does the occipital artery supply?
Scalp
What does the posterior aricular artery supply?
Scalp
What does the maxillary artery supply?
Deep face structures
What does the superficial temporal artery supply?
Scalp
What are the other arteries supplying the scalp, apart from the superficial temporal, occipital and posterior auricular arteries?
Supra-orbital artery
Supra-trochlear artery
What does the supra-orbital artery arise from?
Opthalmic artery
What does the supra-trochlear artery arise from?
Opthalmic artery
Where does the facial artery travel in the face?
Over inferior border of mandible, anterior to masseter muscle
Supero-medially to medial angle of eye
Where is the facial artery palpated?
Inferior border of mandible, anterior to masseter
What does the facial artery do in the face?
Gives off branches
What are the branches of the facial arteries in the face, in the order that they arise?
Inferior labial artery
Superior labial artery
Lateral nasal artery
Angular artery
Where does the inferior labial artery travel in the face?
Below the lower lip
Where does the superior labial artery travel in the face?
Above the upper lip
Where does the lateral nasal artery travel in the face?
Towards middle of nose
Where does the angular artery travel in the face?
To the medial angle of the eye
Where does the maxillary artery travel in the face?
Deep to the superior ramus of the mandible
over the maxilla below the eye
What does the maxillary artery do in the face?
Gives off branches
What are the important branches of the maxillary artery?
Middle meningeal artery
Sphenopalatine artery
Where does the middle meningeal artery travel after it arises?
Through the foramen spinosum
into the cranial cavity
What does the middle meningeal artery do in the cranial cavity?
Divides into an anterior branch and a posterior branch
What does the middle meningeal artery supply?
Calvaria
Dura
Where does the anterior branch of the middle meningeal artery travel after it arises?
Deep to the pterion
How does the anterior branch of the middle meningeal artery affect the inner surface of the calvaria?
Forms a groove within it
What is the clinical significance of the anterior branch of the middle meningeal artery?
Fracture of pterion, which is the weakest part of the skull
could rupture the middle meningeal artery
giving an extra-dural haemorrhage
Where does the sphenopalatine artery travel after it arises?
Through the sphenopalatine fossa
to the nasal septum
What is the blood supply to the nasal septum?
Kiesselbach’s plexus
What is Kiesselbach’s plexus?
Anastamosis of arteries in nasal septum
What are the most important branches of Kiesselbach’s plexus?
Sphenopalatine artery - septal branch
Anterior ethmoidal arteries
Where do the anterior ethmoidal arteries arise from?
Opthalmic artery
What is the clinical significance of the Kiesselbach plexus?
Leakage from this plexus is most commonly the cause of epistaxis
What is epistaxis?
Nosebleed
What are the branches of the subclavian artery, in the order they arise?
Vertebral artery
Internal thoracic artery
Thyrocervical trunk
Where do the vertebral arteries travel after they arise?
Ascend up the neck
How do the vertebral arteries ascend up the neck?
Through the transverse foramina of C1-C6
Where do the vertebral arteries enter the subarachnoid space?
Between the occipital bone and the atlas
Where do the vertebral arteries enter after the neck?
The subarachnoid space
The cranial cavity
What do the vertebral arteries do in the cranial cavity?
Join together to form the basilar artery
How do the vertebral arteries enter the cranial cavity?
Through the foramen magnum
What does the basilar artery supply?
The brain
Where does the basilar artery travel?
Along the anterior aspect of the brainstem
What does the thyrocervical trunk divide into, in order?
Suprascapular arteries
Transverse cervical artery
Inferior thyroid artery
What do the vertebral arteries supply?
Posterior neck
Posterior parts of brain, so the brainstem and cerebellum
What does the inferior thyroid artery do?
Supplies the inferior pole of the thyroid gland
Gives off ascending cervical artery
What do the ascending and transverse cervical arteries supply?
Neck
Where do the internal thoracic arteries travel after they arise?
Run in an inferior direction, laterally to the sternum
What do the internal thoracic arteries do?
Give off anterior intercostal arteries
What do the internal thoracic arteries end as?
Superior epigastric arteries
