Head And Neck Session 2 Flashcards
Which blood vessel is used to measure right atrial pressure and why?
Internal jugular vein as it is straighter therefore gives a better indication
Which jugular vein is more visible?
External
What is the difference in position of the internal and external jugular veins in relation to SCM?
External is superficial, internal is deep to SCM
How is jugular venous pressure calculated?
Height from sternal angle +5 cm
What structure gives the level of the bifurcation of the CCA?
Superior border of the thyroid cartilage
Which branches does the subclavian artery give rise to?
Thyrocervical trunk
Vertebral artery
Internal thoracic artery
What are the branches of the aorta in the neck?
Brachiocephalic trunk –> subclavian and common carotid
Describe the passage of vertebral arteries from the subclavian artery to the brain.
Ascend through L&R transverse foramina of C6-1 to anastomose with the internal carotid artery to form basilar arteries
Which branch of the CCA does not have any branches in the neck?
Internal
Describe the path of the internal carotid artery.
Through carotid canal to anastomose in the circle of Willis
What is the carotid sinus?
Swelling at the region of the carotid bifurcation where baroreceptors are located
What is a carotid body?
Peripheral chemoceptor with rich vascular supply that can detect arterial pO2
Why is the CCA bifurcation a common site for atheroma formation?
Turbulent flow occurs here
What percentage occlusion of the carotid artery must be achieved before it becomes symptomatic?
> 70%
What is the clinical importance of the carotid triangle of the neck?
Pulse point
Surgical access to carotid artery, IJV, vagus and hypoglossal nerves
Carotid sinus massage in SVT pts
Which are the terminal branches of the external carotid artery?
Superficial temporal and maxillary
What are the branches of the external carotid artery?
Maxillary Facial Lingual Superior thyroid Ascending pharyngeal Occipital Posterior auricular Superficial temporal
What are the two branches of the superficial temporal artery?
Frontal and parietal
What are the layers of the scalp?
Skin Dense CT Aponeurosis Loose CT Periosteum
In which layer of the scalp do the blood vessels lie?
Dense CT
Which arteries supply the scalp?
Superficial temporal Occipital Posterior auricular Supratrochlear Supraorbital
What are the supraorbital and supratrochlear arteries branches of?
Ophthalmic artery, a branch of the ICA
Why does the scalp bleed profusely if damaged?
Close attachment of artery walls to dense CT limits constriction
Numerous anastomoses
How can a deep laceration to the scalp cause profuse bleeding?
Opposing pull of occipitofrontalis via the epicranial aponeurosis holds arteries open