Scalp and face

Question 1

What is the ‘S’ layer of the scalp?

Answer 1

Skin

Question 2

What is the ‘C’ layer of the scalp?

Answer 2

connective tissue - (dense: containing nerves and vessels)

Question 3

What is the ‘A’ layer of the scalp?

Answer 3

aponeurosis - (galea aponeurtica)

Question 4

What is the ‘L’ layer of the scalp?

Answer 4

loose connective tissue - (on which the upper 3 layers move upon)

Question 5

What is the ‘P’ layer of the scalp?

Answer 5

pericranium (periosteum of the skull vault)

Question 6

What are the 5 layers of the scalp are bounded by?

Answer 6

1. Superciliary arches
2. Superior temporal lines
3. External occipital protuberance and superior nuchal line

Question 7

Describe general organisation of blood supply in the head and neck: common, external, and internal carotid arteries.

Answer 7

The right side of the head and neck is supplied by the right common carotid artery. The brachiocephalic artery comes off the arch of the aorta, which then divides into the right subclavian artery and the right common carotid artery.
The left side of the head and neck is supplied by the left common carotid artery, this branches directly off of the arch of the aorta.
These common carotid arteries then go on to divide into two branches, internal and external. The internal carotid artery goes directly to the brain and only branches when inside the brain. The external carotid artery has all of the branches, and so is the arterial supply for all of the face and neck.

Question 8

What is a pharyngeal arch, and what does each pharyngeal arch have its own?

Answer 8

Very particular part of the embryo in the neck region
Each has its own:
Cartilage skeleton
Muscular component
Sensory nerve supply
Motor nerve supply

Question 9

What does a muscle bring with it when it migrates?

Answer 9

Its blood and nerve supply

Question 10

Which pharyngeal arch are the muscles of mastication derived from? Which Cranial Nerve are they innervated by?

Answer 10

Muscles of mastication are derived from the 1st pharyngeal arch and are therefore innervated by the Trigeminal nerve (V). The 1st pharyngeal arch later splits in two to form the maxillary and mandibular regions.

Question 11

Which pharyngeal arch are the muscles of facial expression derived from? Which cranial nerve are they innervated by?

Answer 11

Muscles of facial expression are derived from the 2nd pharyngeal arch and therefore are innervated by the facial nerve (VII). They are found in the superficial fascia of the skin - they originate from bone or fascia and insert into the skin.

Question 12

What is the role and features of the occipitofrontalis muscle?

Answer 12

Occipitofrontalis moves the scalp, wrinkles the forehead and raises the eyebrows.
2 bellies; frontal & occipita. Galea aponeurotic 3rd scalp layer is unique as 1 tendon connects to the two muscle bellies

Question 13

What is the function of the two parts of the orbicularis oculi muscle?

Answer 13

Orbital part: broad ring that encircles the orbit and passes over supracililary arch
Closes the eye forcefully and produces some wrinkling of the forehead
Palpebral (eyelid) part: origiates at the medial palpebral ligament and pass laterally over the eyelid
Closes the eye gently

Question 14

What is the role and features of the orbicularis oris?

Answer 14

Completely encircles the mouth and is evident in actions such as whistling or pursing the lips
Fibres originate from the maxilla, mandible and buccinator muscle
Contraction narrows the mouth and closes the lips

Question 15

Role and features of the buccinator

Answer 15

Muscular component of the cheek - used for forcefully expelling air once cheeks have been inflated
Contraction of buccinator keeps the cheek against the teeth therefore aids in mastication
‘Suckling muscle’ or used when you purse your lips

Question 16

What are the 5 terminal branches of the facial nerve from upper to lower?

Answer 16

Temporal (1)
Zygomatic (2)
Buccal (3)
Marginal mandibular (4)
Cervical (5)

Question 17

Which structures pass through or deep to the parotid gland?

Answer 17

Facial nerve (VII)
Exit skull at stylomastoid foramen and passes into the parotid gland
Divides into upper and lower trunks (variable). This is because the facial nerve has to supply all the muscles of facial expression
Passes through the substance of the gland
External carotid artery & branches
Retromandibular vein & tributaries

Question 18

Detail on parotid stones .

Answer 18

Quite common due to the chemical composition of saliva (many salts)
These stones usually get stuck along the duct
This causes intense pain when salivating

Question 19

Detail on facial muscle tightening.

Answer 19

SMAS = Superficial Musculoaponeurotic system of the face
Extended from the platysma to the galea aponeurotica and is continuous with temporoparietal fascia and galea
Connects to the dermis of the skin through vertical septa

Question 20

Detail on Frey’s syndrome.

Answer 20

Innervation of the parotid gland by parasympathetic NS
Complication forms after penetrating wounds to the parotid gland, resulting in parasympathetic secretory fibres of auriculotemporal nerve joining the distal ends of the great auricular nerve.
Results in sweat forming over the skin instead of internal salivation

Question 21

What is unusual about the retromandibular vein?

Answer 21

splits into anterior and posterior portion.

Question 22

What does the pterygoid plexus drain?

Answer 22

Drain regions supplied by the maxillary artery; nasal cavity, roof/lateral aspects of oral cavity, all teeth, muscles of ITF, paranasal sinuses and nasopharynx

Question 23

What is the role of the facial nerve?

Answer 23

Innervation to the muscles of facial expression

Question 24

What is the role of the trigeminal nerve? What are the 3 branches of the trigeminal nerve?

Answer 24

Cutaneous innervation.
V1 Ophthalmic (sensory)
V2 Maxillary (sensory)
V3 Mandibular (mixed)

Question 25

What is the cervical plexus?

Answer 25

a network of nerve fibres that supplies innervation to some of the structures in the neck and trunk.

Question 26

What are the sensory branches of the cervical plexus - ventral rami of C1-C4?

Answer 26

Lesser occipital nerve C2
Great auricular nerve C2,C3
Transverse cervical nerve C2,C3
Supraclavicular nerve C3,C4

Question 27

What are the motor branches of the cervical plexus - ventral rami of C1-C4?

Answer 27

Phrenic nerve - C3,C4,C5 keeps the diaphragm alive
Ansa Cervicalis C1-C3 loop
Infrahyoid muscle