2.1 blood vessels of the head and neck

Question 1

what muscle runs between the internal jugular vein and the external jugular vein?

Answer 1

the sternocleidomastoid

Question 2

where is the carotid sinus?

Answer 2

where the common carotid artery bifuricates in the neck at the superior border of the thyroid cartilage at around C4

Question 3

what vessel lies in close proximity to the recurrent laryngeal nerve and what does it branch from?

Answer 3

the inferior thyroid artery, a branch of the common carotid artery

Question 4

what is contained within the carotid sheath?

Answer 4

the carotid artery
vagus nerve
jugular vein

Question 5

What structure forms the superior border of the carotid triangle?

Answer 5

posterior belly of the digastric muscle

Question 6

What structure forms the medial/inferior border of the carotid triangle?

Answer 6

superior belly of the omohyoid muscle

Question 7

What structure forms the lateral border of the carotid triangle?

Answer 7

medial border of the sternocleidomastoid muscle

Question 8

what is contained in the carotid triangle?

Answer 8

the carotid sinus
common carotid artery and bifurication ( atherosclerosis/ carotid sinus massage/ central pulse)
vagus nerve
hypoglossal nerve
internal jugular vein (access site for central line)

Question 9

why is the bifurication of the common carotid a location that results in much pathology?

Answer 9

Bifurcation is a common site of atherosclerosis. Causes the artery to narrow (stenose). Plaque rupture can release an embolus which can travel to the brain. Can cause a stroke or TIA depending on the size. Can also cause transient loss of vision (Amaurosis Fugax)

Question 10

what is a carotid endarterectomy?

Answer 10

an incision in to the neck and carotid artery at the level of the bifurication to remove plaque tissue.

Question 11

what is a carotid massage?

Answer 11

when you apply pressure at the site of the carotid sinus to increase baroreceptor activity feedback to the heart to slow it down

Question 12

why is the internal jugular vein a good site for a central venous line?

Answer 12

as it is a large vein and very superficial so easy to access

Question 13

what branches does the internal jugular artery give in the neck?

Answer 13

none - enters the base of the skull via the carotid canal an supplies intracranial structures

Question 14

the vertebral arteries branch form which major artery?

Answer 14

arise from the left and right subclavian arteries

Question 15

describe the path of the vertebral arteries?

Answer 15

branch from the subclavian veins
ascend up the cervical vertebrae through the transverse foramina
enter the base of the skull via the foramen magnum
left and right vertebral arteries terminate by fusing and forming the basilar artery

Question 16

where is the carotid canal?

Answer 16

in the petrous part of the temporal bone

Question 17

after leaving the carotid canal, what does the internal carotid artery travel through?

Answer 17

the cavernous sinus

Question 18

what is the venous sinus?

Answer 18

Venous type structure on the upper surface of the sphenoid bone

Question 19

what structures

run through the cavernous sinus?

Answer 19

CNV1 ophthalmic division 
CN V2 maxillary division
CN III oculomotor 
CN IV trochlear
CN V trigeminal (only 2 divions)
CN VI abducens 
internal carotid artery

Question 20

what does the ophthalmic artery branch from?

Answer 20

the internal carotid artery

Question 21

what important structure does the ophthalmic artery follow?

Answer 21

the optic nerve

Question 22

what are the 3 main branches of the ophthalmic artery?

Answer 22

supratrochlear artery
supra-orbital artery
central retinal artery

Question 23

how can carotid artery atherosclerosis cause blindness?

Answer 23

if an emboli dislodges and travels via the ophthalmic artery to block the central retinal artery

Question 24

what are the main branches of the internal carotid artery?

Answer 24

ophthalmic artery
anterior cerebral artery
middle cerebral artery
posterior communicating artery

Question 25

what are the branches of the external carotid artery?

Answer 25

some anatomists like freaking out poor medical students 
superior thyroid
ascending pharyngeal
lingual 
facial
occipital
posterior auricular 
maxillary 
superficial temporal

Question 26

what is the clinical importance of the superficial temporal artery?

Answer 26

Giant cell arteritis (GCA) / Temporal arteritis

• Frequent, severe headaches
• Scalp tenderness particularly over the temple
• Jaw pain while eating/talking
• Loss of vision/visual changes Without treatment patients can permanently lose their eye sight

Question 27

how is giant cell arteritis treated?

Answer 27

emergency! high dose steroids

Question 28

what arteries contribute to the blood supply of the scalp?

Answer 28

supraorbital artery
supratrochlear artery 
superficial temporal artery
posterior auricular artery
occipital artery

Question 29

what are the different layers of the scalp?

Answer 29

skin
connective tissue
aponeurosis
loose areolar tissue 
periosteum 
bone

Question 30

why does the scalp bleed so heavily in head injuries?

Answer 30

Artery walls held open by connective tissue and so cant constrict. Lots of anastomoses
Lacerations deep enough to involve the epicranial aponeurosis of occipitofrontalis can pull cuts open

Question 31

what are the superficial arteries of the face?

Answer 31

Supraorbital art. 
Supratrochlear art.
Transverse facial art.
Angular art. 
Lateral nasal art.
Maxillary art.
Superior & Inferior Labial art.
Facial art.

Question 32

what does the maxillary artery supply?

Answer 32

deeper facial structures

Question 33

what are the key branches of the maxillary artery?

Answer 33

sphenopalatine artery

middle meningeal artery

Question 34

what passes through the foramen spinosum?

Answer 34

the middle meningeal artery

Question 35

what vessel passes under the pterion?

Answer 35

anterior middle meningeal artery

Question 36

what is the most common cause of an extradural haemorrhage?

Answer 36

a middle meningeal artery rupture

Question 37

what is the management of a extradural haemorrhage?

Answer 37

Needs specialist neurosurgical treatment
Craniotomy – opening of the cranium to relieve the pressure
Evacuate the clot forming and stop the bleeding

Question 38

what veins drain the scalp into the external jugular vein?

Answer 38

suprorbital vein
supratrochlear vein
superficial temporal vein
occipital vein
posterior auricular vein

Question 39

what drains into the dural venous sinuses?

Answer 39

brain structures

scalp via the emissary veins

Question 40

why do emissary veins pose an infection risk?

Answer 40

as the emissary veins drain the scalp, an extracranial structure with direct connection to the external environment into the dural venous sinuses that are intracranial. This allows infections to spread from extracranial to intracranial

Question 41

what structures drain into the cavernous sinus?

Answer 41

brain
superior and inferior ophthalmic veins
facial veins

Question 42

what is the danger triangle of the face?

Answer 42

in the midline of the face, encompassing the nose and the upper lip.
The region where the facial vein can drain backwards into the cavernous sinus
Infections in that area can spread via the deep facial vein and ultimately end up in the dural venous sinuses

Question 43

what is the confluence of the sinuses?

Answer 43

an area at the back of the skull where the superior sagittal sinus and the inferior sagittal sinus meet

Question 44

what is the sigmoid sinus?

Answer 44

a continuation of the transverse sinus proceeding the internal jugular vein

Question 45

how do we measure jugular venous pressure?

Answer 45

We use the right Int. Jugular Vein as connects linearly with the right atrium
Patient at 45 degrees Head turned slightly to the left
IJV mostly hidden by sternocleidomastoid
Look for pulsations through the muscle
Measure the height from the sternal angle and add 5cm, gives an estimate of the right atrial pressure in cmH2O