2.1 Major blood vessels of the Head and Neck Flashcards
Where do the right subclavian and right common carotid originate from?
Brachiocephalic trunk
What arteries arise from the subclavian artery?
Vertebral artery, Internal thoracic artery and Thyrocervical arteries
What does the thyrocervical trunk supply?
Ascending cervical and transverse cervical supply to the neck
Suprascapular artery- shoulder
Inferior thyroid artery- lower pole of thyroid
Describe the route of the vertebral arteries
From subclavian artery to up through transverse foramina in C1-C6, supplies the brain
At what level does the common carotid bifurcate?
The superior border of the thyroid cartilage
What is the carotid sinus?
Swelling at the region of the bifurcation of the common carotid. Location of baroreceptors to detect changes in arterial blood pressure
What is the carotid body?
Peripheral chemoreceptors which detect arterial O2 found in the bifurcation of the common carotid
Describe a carotid artery atheroma
Atheroma formation in the bifurcation of the common carotid. Causes narrowing of the artery and turbulent flow. Emboli can easily move into the brain and cause a stroke
What is the carotid sheath?
A layer of fascia surrounding the common carotid, IJV, vagus nerve and deep cervical lymph nodes
Name the branches of the external carotid artery
Superior thyroid Ascending pharyngeal Lingual Facial Occipital Posterior auricular Superficial temporal Maxillary
Which arteries supply the scalp?
Occipital Posterior auricular Superficial temporal Supratrochlear Supraorbital
Which artery do the supratrochlear and supraorbital originate from?
Opthalmic artery
List the layers of the scalp
Skin Connective tissue Aponeurosis Loose connective tissue Periosteum (Spells SCALP)
Where do the vessels of the scalp lie?
Subcutaneous connective tissue layer
Why can damage to the scalp cause profuse bleeding?
The arteries are closely attached to the connective tissue and there are many anastamoses
How can deep lacerations to the skull cause profuse bleeding?
If the epicranial aponeurosis is damaged the opposing pull of the occipitofrontalis muscle keeps the scalp pulled open
Name the major superficial veins in the scalp
Superficial temporal
Occipital
Posterior auricular
What do the supratrochlear and the supraorbital veins merge to become?
Angular vein
Where does the angular vein drain into?
Facial vein
Where do the veins of the scalp drain to?
Dural venous sinuses
Which veins drain the blood from the skull to the dural venous sinuses?
Diploic veins
Which veins drain the blood from the outer layer of the scalp to the dural venous sinuses?
Emissory veins
Where do the dural venous sinuses lie?
Between the periosteal and the meningeal layers of the dura
What is the cavernous sinus?
A plexus of extremely thin-walled veins on the upper surface of the sphenoid
What other structures lie in the cavernous sinus?
Internal carotid artery
CN III, IV, VI, V1 and V2
What artery supplies the skull with blood?
Middle meningeal artery
Where is the middle meningeal artery vulnerable?
The pterion
What happens if the middle meningeal artery ruptures?
Extradural haemorrhage- pulls periosteal layer off the skull
What is a craniotomy?
Surgery to gain access inside the cranial cavity
Where does the IJV lie?
Under the SCM
