H&N 3: Blood Vessel And Lymphatics Flashcards
The vertebral arteries are branches of which arteries?
Subclavian
What is the path of the vertebral arteries?
From subclavian arteries, ascend through the transverse foramina of the cervical vertebrae and go through the foramen magnum. They curve around the medulla and meet the vertebral artery on the other side to form the basilar artery
What do the vertebral arteries supply?
Posterior parts of neck and posterior parts of brain
Which common carotid artery is longer and why?
The left is slightly longer, as it arises directly form the arch of the aorta whereas the right CCA arises from the brachiocephalic trunk
Where do the common carotids terminate?
At the superior level of the thyroid gland
Here they divide into their internal and external branches
How can rubbing the carotid sinus alleviate supra ventricular tachycardias?
This is where the baroreceptors are located
Rubbing stimulates the effect of raised BP so will signal to the heart to beat slower
How could you tell the difference between the IJV and EJV in the neck?
IJV lies under SCM, lateral to common carotid
EJV lies over SCM, and has lots of branches
The carotid sinus and carotid body have which important receptors?
Carotid sinus has baroreceptors which detect arterial BP changes
Carotid body has chemoceptors which deter arterial O2
Is the carotid triangle a division of the anterior or posterior triangle?
Anterior
What are the boundaries of the carotid triangle?
Superior: posterior belly of digastric
Lateral: SCM
Medial: superior belly of omohyoid
What are the contents of the carotid triangle?
Bifurcation of the common carotid artery, internal jugular vein
What are the branches of the external carotid artery?
(Some anatomists like freaking out poor medical students) Superior thyroid Ascending pharyngeal Lingual Facial Occipital Posterior auricular Maxillary Superficial temporal
What is the blood supply to the scalp? And which branches are from the ICA or the ECA?
Supraorbital & supratrochlear are from the ICA (branches of ophthalmic)
Superficial temporal, posterior auricular and occipital are from the ECA
What is the venous drainage of the scalp?
Supraorbital Supratrochlear Superficial temporal Posterior auricular Occipital
How is a scalp infection able to spread to the cranial cavity and possibly affect the meninges?
Valveless emissary veins of the scalp connect to diploic veins of the skull and then to dural venous sinuses
What is the significance of a skull fracture at the pterion?
Weakest part of the cranium, anterior branch of middle meningeal artery lies behind the pterion so is likely to be damaged, if ruptured it can lead to an extradural haematoma where blood accumulates between the dura and the skull
Which bone does the cavernous sinus lie by?
Sphenoid bone
What is the cavernous sinus?
A pair of dural venous sinuses
Located next to the sphenoid bone
Within it is: internal carotid artery (allows arterial blood to cool before reaching the brain), CN III (oculomotor), IV (trochlear), V1 (ophthalmic), V2 (maxillary), V1 (abducens)
How can an infection of the face spread to the venous sinuses?
The facial vein is connected to the cavernous sinus by the superior ophthalmic vein
Facial vein is valveless so blood can reverse direction
JVP is observing pulsations through which vein?
IJV
this lies behind SCM so we look for muscle pulsing
Use the right IJV as it effectively connection to the right atrium
Have the patient at 45 degree angle
What is the difference between regional and terminal lymph nodes in the head and neck?
Regional lymph nodes drain into terminal lymph nodes
Regional lymph nodes drain specific areas, lie in the superficial cervical fascia and can be readily palpated
Terminal lymph nodes receive drainage from a number of regional lymph nodes, and lie in the deep cervical fascia (most are in the carotid sheath)
What are the superficial lymph nodes of the head and neck?
Submental Submandibular Pre auricular Post auricular Occipital Superficial cervical Anterior cervical Posterior cervical
What are the deep lymph nodes of the head and neck?
Jugulodigastric
Juguloomohyoid
Supra clavicular
How would swollen lymph nodes feel in infection?
Tender and mobile