H&N3 - Major Blood Vessels of Head & Neck

Question 1

What are the main arteries of the neck?

Aorta + 11 others

Answer 1

1. ) Aorta –> Brachiocephalic Trunk + Left Common Carotid + Left Subclavian
2. ) Brachiocephalic Trunk –> Right Subclavian + Right Common Carotid
3. ) Common Carotid –> Internal Carotid (no branches) + External Carotid
4. ) Subclavian –> Thyrocervical Trunk + Internal Thoracic + Vertebral
5. ) Thyrocervical Trunk –> Ascending Cervical + Transverse Cervical + Inferior Thyroid + Suprascapular

Question 2

5 features of the Common Carotid Artery

Answer 2

1.) Found in carotid triangle under SCM and medial to the IJV
2.) CC bifurcates at the level of the superior border of the thyroid cartilage (C4)
3.) Bifurcation is a common site for atheroma formation causing stenosis –> TIA. If it ruptures, can cause a stroke
4.) Carotid Sinus and Body - sinus is a swelling at region of bifurcation where baroreceptors are found.
- carotid body contains peripheral chemoreceptors detecting arterial oxygen
5.) Carotid sinus massage can be used to cause bradycardia since
the baroreceptors detect an increase in pressure
- can be used in patients with SVTs..

Question 3

4 features of the Internal Carotid Artery (ICA) and Cavernous Sinus

Route
Cavernous Sinus
Cavernous Sinus Contents x5
Ophthalmic Artery Branches x4

Answer 3

1. ) Route - enters the skull through the carotid canal and courses through the cavernous sinus
2. ) Cavernous Sinus - plexus of veins on the upper surface of the sphenoid
3. ) Cavernous Sinus Contents - ICA, CNIII (oculomotor), CNIV (trochlear), CNV (trigeminal), CNVI (abducent), -
   - it contains 2 branches of the trigeminal nerve: CNVa (ophthalmic) and CNVb (maxillary)

4.) ICA branches off the ophthalmic artery which has 4 important branches: supratrochlear, supraorbital, anterior and posterior ethmoidal

Question 4

What are the 8 branches of the External Carotid Artery (ECA)?

6 branches, 2 terminal branches

Some Anatomists Like Freaking Out Poor Medical Students

Answer 4

6 Branches
Superior Thyroid
Ascending Pharyngeal
Lingual
Facial
Occipital
Posterior Auricular

2 Terminal Branches
Maxillary
Superficial Temporal

Question 5

5 features of blood supply and venous drainage to the scalp

5 arteries and veins

Answer 5

1.) Blood supply made up of ICA and ECA branches,
ICA: supratrochlear and supraorbital (ophthalmic)
ECA: superficial temporal, posterior auricular, occipital
2.) All 5 arteries have corresponding veins.
3.) Supratrochlear vein + supraorbital vein –> angular vein –> facial vein –> IJV
4.) Some deep parts of the scalp in temporal region have veins which drain to the pterygoid venous plexus
5.) Emissary veins connect veins in the skull to dural venous sinuses
- this means infection from scalp can spread to the cranial cavity and affect meninges

Question 6

3 features of blood supply to the nasal septum

5 arteries

Answer 6

1. ) 5 Arteries:
   - anterior and posterior ethmoidal (ophthalmic),
   - septal branch of sphenopalatine (branch of maxillary), greater palatine, septal branch of superior labial (ECA)
2. ) There is an anastomoses of all 4 arteries in the Kiesselbach area
3. ) Kiesselbach area is the most common site for nose bleeds (epistaxis)

Question 7

4 features of blood supply to the dura and skull

Answer 7

1. ) supplied by the anterior and posterior MMA (maxillary) which passes through the foramen spinosum
2. ) MMA runs between the inner table of the skull and the periosteal layer of the dura
3. ) grooves/impressions are present on skull showing the travel path of the arteries
4. )fracture at the pterion can rupture the MMA causing an extradural haemorrhage

Question 8

Clinical relevance of blood supply to the scalp

4 points

Answer 8

1. ) Rich blood supply with many anastomoses means profuse bleeding if an artery is damaged
2. ) Walls of arteries are closely attached to connective tissue which limits constriction so you can get profuse bleeding
3. ) Deep laceration involving epicranial aponeurosis causes profuse bleeding because the opposing pull of occiptofrontalis opens blood vessels
4. ) Blood supply to the skull is mostly the middle meningeal artery (MMA) so loss of scalp doesn’t lead to bone necrosis

Question 9

4 features of blood supply and venous drainage of the face

9 Arteries 9 Veins

Answer 9

1. ) 9 Arteries - supraorbital and supratrochlear, transverse facial, angular, lateral nasal, maxillary, superior and inferior labial, and facial artery
2. ) facial artery can be pulsated at inferior border of the mandible, anterior to the masseter muscle
3. ) 9 Veins - supraorbital and supratrochlear, angular, superior and inferior labial, facial, common facial, IJV, EJV
4. ) facial vein drains into the cavernous sinus and deep facial veins drain into the pterygoid venous plexus
   - infection from facial vein can spread to dural venous sinuses

Question 10

3 features of the dural venous sinuses

Answer 10

1. ) lie between the periosteal and meningeal layers of the dura mater
2. ) there are 11 venous sinuses which all converge at the confluence of sinuses
3. ) from the confluence, the transverse sinus continues and curves into the sigmoid sinus which continues as the IJV, leaving the skull through the jugular foramina

Question 11

5 features of measuring jugular venous pressure (JVP)

Answer 11

1. ) Use the right IJV because of the direct connection to the right atrium
2. ) Patient is sat at a 45 degree angle w/ head tilted to the left
3. ) The pulsations are observed through SCM
4. ) You measure the height from sternal angle you can see the pulsations then add 5cm
5. ) It is measured in cmH2O