Lecture 3- Internal branch of the carotid artery

Question 1

the head and neck recieves most its blood supply through the

Answer 1

carotid and vertebral arteries

Question 2

anatomy of of the carotid arteries. arise from the arch of the aorta

Answer 2

Question 3

the right common carotid arery arises from

Answer 3

a bifurication of the brachiocephalic trunk (right subclavian is the other branch)

• occurs roughly at the level of the right sternoclavicular joint

Question 4

the left common carotid branches

Answer 4

directly from the arch of the aorta

Question 5

the left and right common carotid arteries ascend up the neck…… to the trachea and the oesophagus

Answer 5

lateral

Question 6

when does the carotid arterie bifuracte into the external and interal carotid arteries

Answer 6

superior margin of the thyroid cartilage (C4)

bifurcation occurs in an anatomical area known as the carotid triangle.

Question 7

features of the common carotid and itnenra carotid at the carotid triangle

Answer 7

slightly dilated here, this area is known as the carotid sinus, and is important in detecting and regulating blood pressure

Question 8

what is also found in the carotid sinus

Answer 8

baroreceptors for HR

the glossopharyngeal nerve feeds this information to the brain, and this is used to regulate blood pressure.

Question 9

Importance of carotid triangle

Answer 9

• Bifurcation of the common carotid occurs here
• Important clinically
  
  • Surgery
  • Atherosclerosis
  • Carotid sinus massage
  • Central pulse
• Access site for vagus and hypoglossal nerves
• Contains internal jugular vein (access site for central line placement)

Question 10

Carotid triangle borders

Answer 10

• Superior border- posterior belly of the digastric muscle
• Medial/inferior border- superior belly of omohyoid muscle
• Lateral border- medial border of SCM

Question 11

the carotid sinus is a common site of

Answer 11

Atherosclerosis

• Bifurcation is a common site of atherosclerosis
• Causes artery to narrow (stenose)
• Plaque rupture can release an embolus which can travel to brain
  
  • Stroke or TIA depending on size
  • Transient loss of vision (amaurosis)

Question 12

procedure on carotid sinus with atherosclerosis

Answer 12

Carotid endarterectomy - to reduce risk of stroke

• Incision in neck and the carotid to remove plaque tissue and stich back up
• Important to know carotid triangle boundaries

Question 13

Carotid sinus massage

Answer 13

• Pressure at the site of carotid bodies
• Increased baroreceptor activity feedback to the heart to slow down
• Important area to feel in clinical examination to determine pulse

Question 14

interanal carotid arteries do not supply

Answer 14

any sturctures in the neck- no branching in the neck

Question 15

where does the intenral carotid artery enter the cranial cavity

Answer 15

via the carotid canal in the petrous part of the temporal bone

Question 16

the internal carotid artery supplies:

Answer 16

The brain

Eyes

Forehead

Question 17

​​Vertebral arteries arise from

Answer 17

left and right subclavian arteries

*

Question 18

how do the vertebral artery ascend up the neck into the skull

Answer 18

• Ascend up the cervical vertebrae through the transverse foramina
• Entering the base of the skull via the foramen magnum

Question 19

internal carotid arteires and vertebral arteries supply the

Answer 19

brain with blood

Question 20

where is the carotid canal found

Answer 20

within the petroud part of the temporal bone

allows intenral carotid to pass through the base and enter the skull

Question 21

how does the internal carotid artery enter the brain via the carotid canal

Answer 21

• Turns medially and horizontally
• Enters the cranium and makes an s-shaped bend
• Moves through cavernous sinus

Question 22

Cavernous sinu

*

Answer 22

• Venous type structure on the upper surface of the sphenoid bone
• Vessels that flow through the carotid sinus:
  
  • Carotid artery
  • CN III (Oculomotor)
  • CN IV (Trochlear)
  • CN VI (Abducens)
  • 2 branches of CN V (Trigeminal) ( CN V1 ophthalmic and CN V2 maxillary)

Question 23

first branch of the internal carotid artery

Answer 23

opthalmic artery (which follows the opthalmic nerve)

Question 24

branches of the opthalmic artery

Answer 24

• central rentianl artery (if you lose blood supply to the ophthalmic artery the retina will die and lose sight)
• supra-orbital artery
• surpatrochlear artery

Question 25

the circle of willis

Answer 25

Question 26

other branches of the itnernal carotid

Answer 26

Other branches provide arterial blood to the brain

◦ Anterior cerebral artery
◦ Middle cerebral artery
◦ Posterior communicating artery