Lecture 3- External branch of the carotid artery

Question 1

external carotid artery supplies areas of the head and neck…

Answer 1

external to the cranium

• face
• scalp

Question 2

how does the external carotid artry ascend up the neck

Answer 2

passing posteriorly to the mandibular neck and anteriorly to the lobule of the ear.

Question 3

where does the external carotid artery end

Answer 3

The artery ends within the parotid gland by dividing into the superficial temporal artery and the maxillary artery

Question 4

how many branches does the ECA give off

Answer 4

8

Question 5

pneumonic for learning 6 branches of the external carotid

Answer 5

some

ancient

lover

find

old

positions

more

stimulating

Question 6

some

Answer 6

superior thyroid (anterior branch)

Question 7

ancient

Answer 7

ascending pharyngeal (anterior)

Question 8

lovers

Answer 8

lingual (anterior)

Question 9

find

Answer 9

facial (medial)

Question 10

old

Answer 10

occipital (posterior)

Question 11

positions

Answer 11

posterior auricular (posterior)

Question 12

more

Answer 12

maxillary (terminal)

Question 13

stimulating

Answer 13

superficial temporal (terminal)

Question 14

major branches of the external carotid

Answer 14

facial, maxillary and superfificial

Question 15

maxillary artery

Answer 15

supplies the deep structures of the face

Question 16

facial and superficial temporal arteries generally supply

Answer 16

superficial areas of the face

Question 17

which arteries combine to provide a dense blood supply to the scalpe (which is one reason why injuries to thesscalp cause excessive beleeding)

Answer 17

posterior auricular, occupital and superficial temporal artery

and

two branches of the itnernal carotid artery: supra-orbital and supratrochlear

Question 18

Injuries to the scalp can cause excessive bleeding for various reasons:

Answer 18

1. The walls of the arteries are tightly and closely bound to the underlying connective tissue of the scalp. This prevents them from constricting to limit blood loss following injury or laceration.
2. The numerous anastomoses formed by the arteries produce a very densely vascularised area.
3. Deep lacerations can involve the epicranial aponeurosis, which is worsened by the opposing pulls of the occipital and frontalis muscles.

Question 20

which external carotid artery branch supplies some intracranial structures

Answer 20

middle menigeal artery (branch of the maxilalry artery)

Question 21

middle menigeal artery supplies

Answer 21

• the skull and the dura mater (the outer membranous layer covering the brain). A fracture of the skull at its weakest point, the pterion, can injure or completely lacerate the MMA. Blood will then collect in between the dura mater and the skull, causing a dangerous increase in intra-cranial pressure. This is known as an extradural haematoma.
• The increase in intra-cranial pressure causes a variety of symptoms: nausea, vomiting, seizures, bradycardia and limb weakness. It is treated by diuretics in minor cases, and drilling burr holes into the skull the more extreme haemorrhages.

Question 23

why is the superifical temporarl artery clinically significant

Answer 23

giant cell arteritis (GCA) e.g. temporal arteritis

Question 24

Giant cell arteritis (GCA)/ temporal arteritis

Answer 24

• facial arteries become inflamed and reduce blood supply to the structures they supply
  
  • Frequent, severe headaches
  • Scalp tenderness particularly over the temp
  • Jaw pain while eating/ talking
  • Loss of vision/ visual changes
    
    • Without treatment loss of eye site
    • Treat with high dose of steroids
• Temporal arteritis
  
  • Temporal, jaw, eye regions affected

Question 26

layers of the scalp

Answer 26

scalp pneumonic works

• skin
• connective tissue
• aponeurosis
• loose areolar tissue
• periosteum

Question 27

superfiical arteries of the face

Answer 27

Question 28

where does the middle menigeal enter the skull

Answer 28

foramen spinosum

• splits into anteiror and postewrior middle meningeal artery
• anterior passes under the area of the skull called the pterion (where the bones of the skull come together)