Vessels of the Head and Neck Flashcards
What are the main arteries of the head and neck?
Common Carotid (I&E) Vertebral Arteries Inferior Thyroid Suprascapular Superficial Cervical
What are the branches that come off the subclavian artery?
Vertebral Arteries
Thryocervical Trunk
Internal Thoracic
Describe the course of the common carotid
Ascends in the Carotid Sheath
Anterior to SCM and IJV
Splits at the level of C4, superior border of the thyroid cartilage
Anterior triangle
What is the Carotid Sinus?
A swelling at the bifurcation
Has baroreceptors which detect arterial BP changes
What is the Carotid Body?
Located at the bifurcation
contain peripheral chemoreceptors
detect the change in pO2
Quite insensitve
What can happen at the level of C4?
Bufurcation can narrow (stenosis)
turbulance can occur, atheroma formation
If this embolises it can cause stroke or TIA
What does the ICA supply?
Internal structures of the head
No branches in the neck
Give some branches of the ICA
Opthalmic Artery - Supplies Eyes
Branches to Supraorbital and Supratrochlear which supply the scalp
What are the branches of the ECA?
Some Anatomists Like Freaking Out Poor Medical Students
What are the terminal branches of the ECA?
Superficial Temporal
Maxillary
Which branches of the ECA supply the scalp?
Occipital
Superficial Temporal
Posterior Auricular
Which branches of the ICA supply the scalp?
Supratrochlear
Supraorbital
Both come from the Opthalmic branch of the ICA
What are the layers of the scalp?
Skin Dense Connective Tissue Aponeurosis Loose CT Periostium
Which branch of the ECA suppies the deep facial structures?
Maxillary Artery
What are the important branches of the Maxillary Artery (ECA)?
Middle Meningeal (Supplies dura and skin) can cause extradural haemorrage if damaged at the pterion
Sphenopalatine
Infraorbital,
Buccal and Inferior Alveolar
What is the order of the brain covering? aka the Meninges
Dura Mater
Arachnoid Mater
Pia Mater
What are the layers of the dura mater?
What runs in them?
Describe these…
Periosteal layer and Meningeal Layer Dural Venous Sinuses Superior and Inferior Saggital Sinuses, Transverse and Vertical Drain to Cavernous Sinus Lined by endothelium
How do veins of the scalp drain?
Drain via emissary veins (valveless) into dural venous sinuses, which drain to the cavernous sinus/ptergoid plexus and then the the IJV
What are the branches of the thyrocervical trunk?
Inferior Thryoid
Suprascapular
Superficial Cervical
Where do the vertebral arteries run?
What do they supply?
In the transverse foramina of C6 to C1 The brain (makes up circle of Willis with the ICA)
What is the drainage of the supraorbital/tochlear veins?
Join to form the angular vein
which drains to the facial vein
What is the drainage of the facial vein?
Facial Vein drains the the IJV, can go via the pterygoid plexus and cavernous sinus
What is the drainage of the deep parts of the scalp?
They drain to the pterygoid plexus
What is the significance of the scalp being drained this way?
Infection of the scalp can spread to the cranial cavity and cause meningitis
Which vessel do we use to estimate the JVP?
External Jugular Vein
Easier to access
What can cause a raised JVP?
Right Heart Failure
Fluid Overload
Tricuspid Regurgitation
Pulmonary Embolism (Massive) SVC Obstruction Pericardial Tamponade
What is the course of the IJV?
Exit the skull via the jugular foramen
Descend the neck in the carotid sheath
Lateral the the common carotid
Deep to the SCM
What is the course of the EJV?
Runs through the carotid triangle
crosses the SCM anteriorly then goes into the posterior triangle where it goes behind the SCM
Unites with the Subclavian to become the brachiocephalic
What causes lots of bleeding with a cut on the scalp?
Aponeurosis is pulled by occipitofrontalis which holds a deeper laceration open
Anastomoses cause a lot of bleeding
What do the branches of the thryocervical trunk supply?
Inferior Thyroid…
Suprascapular - Shoulder
Cervical - Neck
