A14 - Blood Supply to the Head

Question 1

What is endocarditis?

Answer 1

an infection in the inner lining and cardiac valves of the heart caused by bacteria infection via the bloodstream

Question 2

What are the great vessels of the heart?

Answer 2

superior/inferior vena cava
pulmonary trunk - left/right pulmonary arteries
Aorta - brachiocephalic trunk, left common carotid, left subclavian

Question 3

What are the branches of the subclavian artery and where do they supply?

Answer 3

vertebral artery - through transverse foramen to brain
thyrocervical trunk - splits to supply the thyroid gland and neck
internal thoracic artery- inside the thorax to supply anterior chest wall

Question 4

What are the two branches of the common carotid artery and where do they supply?

Answer 4

external - leaves the carotid sheath and is external to the cranium

internal - remains in the carotid sheath and is internal to the cranium

Question 5

Where does the bifurcation of the common carotid occur?

Answer 5

level of the superior border of the hyoid bone (thyroid cartilage)

Question 6

What is the proximal band of the internal carotid artery that contains baroreceptors?

Answer 6

carotid sinus

Question 7

What is the difference between the carotid sinus and the carotid body?

Answer 7

the sinus contains baroreceptors, the body contains chemoreceptors

Question 8

What is the meaning of anastomose?

Answer 8

the joining together or arteries

Question 9

How is the circle of willis formed?

Answer 9

vertebral arteries join to create the basilar artery which joins with the internal carotid

Question 10

List the branches of external carotid and the area they supply

Answer 10

superior thyroid 
ascending pharyngeal - pharynx
lingual - tongue
facial - face 
occipital - occipital region 
posterior auricular - behind the ear 
maxillary - maxilla 
supeior temporal - temporal

Question 11

How does bacteria drain from the mouth area?

Answer 11

• inferior alveolar vein drains into the retromandicular vein
• this will drain blood into the internal jugular
• internal jugular will converge with the subclavian
• then into the brachiocephalic vein
• into the superior vena cava to the heart resulting in endocarditis

Question 12

What is the anterior division of the retromandibular vein?

Answer 12

anterior branch of retromandibular joins + facial vein = common facial vein

this will drain into the internal jugular vein

Question 13

what is the posterior division of retromandibular vein?

Answer 13

posterior branch of retromandibular + posterior auricular = external jugular

this will drain into internal jugular

Question 14

What is the importace of the danger triangle?

Answer 14

• facial vein is linked to the intra-cranial dural sinus in the brain
• therefore a communication from the external surface to internal cavity in which bacteria can spread