Anatomy of the Face, Scalp and Parotid

Question 1

List the 5 layers of the scalp, from superficial to deep

Answer 1

Skin
Connective tissue
Aponeurosis
Loose connective tissue
Periosteum/pericranium

Question 2

What is the significance of the loose connective tissue layer of the scalp?

Answer 2

Allows movement of the skin, connective tissue and aponeurosis on the periosteum

Question 3

Which layer of the scalp contains the neurovascular plane?

Answer 3

Connective tissue (also contains fat)

Question 4

What are the anatomical margins of the scalp?

Answer 4

Supraorbital margins anteriorly
External occipital protuberance posteriorly
Level of the zygomatic arches laterally

Question 5

Why do scalp wounds gape?

Answer 5

Because the laceration divides the aponeurosis between the frontalis and occipitalis bellies of occipitofrontalis

Question 6

Why do scalp wounds often bleed profusely?

Answer 6

Because the neurovascular plane contains rich anastamoses between the internal and external carotid arteries, and these vessels are held open by fibrous septa which adhere to their margins, preventing constriction and clotting

Question 7

Why is facial infection a risk factor for encephalitis?

Answer 7

Because some blood from the face (particularly a triangular area surrounding the nose) is sometimes drained via emissary veins into the cranial sinuses

Question 8

Where do the muscles of facial expression originate and insert?

Answer 8

Arise from underlying bone or fascia

Insert into skin of face

Question 9

Which nerve is the 2nd pharyngeal arch associated with?

Answer 9

Facial (CNVII)

Question 10

List the 4 layers of the face, from superficial to deep

Answer 10

Skin
Connective tissue
Muscles of facial expression
Periosteum/pericranium

Question 11

What nerve supplies the skin of the head anterior to the ears?

Answer 11

Trigeminal (CNV)

Question 12

What are three divisions of the trigeminal nerve and what does each branch supply?

Answer 12

Opthalmic: orbit, forehead, top of scalp
Maxillary: cheek, maxilla
Mandibular: mandible (jaw)

Question 13

What nerve supplies the skin of the head posterior to the ears?

Answer 13

Dorsal rami of the cervical spinal nerves (except C1 which has no cutaneous supply)
C2: back of head
C3: neck
Below: back

Question 14

What symptom is characteristic of trigeminal neuralgia?

Answer 14

Episodes of intense, disabling facial pain (tend to be over 1 of the 3 divisions of the nerve)

Question 15

Which foraminae is each of the branches of the trigeminal nerve associated with?

Answer 15

Opthalmic: superior orbital fissue
Maxillary: foramen rotundum
Mandibular: foramen ovale

Question 16

Where does the ganglion of the trigeminal nerve sit?

Answer 16

At the apex of the petrous part of the temporal bone

Question 17

What arteries supply the centre of the forehead and what are these arteries branches of?

Answer 17

Supratrochlear (more medial) and supraorbital (more lateral) branches of the internal carotid artery (via the opthalmic artery)

Question 18

What is the branch of the external carotid artery supplying the scalp and where does it run?

Answer 18

Superficial temporal, running over the zygomatic arches to the forehead

Question 19

Describe the course of the facial artery

Answer 19

Given off by the external carotid artery, winds over inferior angle of mandible (following a tortuous course), gives off branches to the face and nose, ends at the medial angle of the eye

Question 20

What arteries supply the posterior head?

Answer 20

Posterior auricular

Occipital

Question 21

Describe the lymph drainage of the head

Answer 21

Lymph drains into a ring of lymph nodes surrounding the base of the skull, which includes:
Submental nodes
Submandibular nodes
Pre-auricular and parotid nodes
Mastoid (or post-auricular) nodes
Occipital nodes
These then drain to the deep cervical nodes

Question 22

What is the parotid and where is it located?

Answer 22

A serous salivary gland located inferior to the zygomatic arch, anterior to the ear and the mastoid process of the temporal bone, superior to the angle of the mandible, posterior to the masseter, and superficial to the styloid process of the temporal bone

Question 23

What is the significance of the parotid fascia?

Answer 23

Swelling of the parotid gland causes pain because the fascia is a dense fibrous envelop and has no “give”

Question 24

What four structures are related to the parotid gland?

Answer 24

Parotid lymph nodes are scattered throughout
From superficial to deep, the following structures pass through:
Facial nerve (CNVII)
Retromandibular vein
External carotid artery

Question 25

Describe the course of the facial nerve

Answer 25

Runs through the internal auditory meatus, travels through the stylomastoid foramen, gives off the posterior auricular branch, enters the back of the parotid gland, creates plexiform arrangement (“pes anserinus”) within the gland from which 5 terminal branches emerge

Question 26

What two veins join to form the retromandibular vein?

Answer 26

The superficial temporal and maxillary veins

Question 27

What happens to the external carotid artery as it enters the parotid gland?

Answer 27

Divides into two terminal branches, the superficial temporal and maxillary arteries

Question 28

Which artery gives off the middle meningeal artery, and how does it enter the skull?

Answer 28

The maxillary artery

Via foramen spinosum

Question 29

What symptoms does injury to the facial nerve produce?

Answer 29

Full or partial paralysis of the muscles of facial expression on the side of the injury
Flattening of the nasolabial fold
Sometimes dribbling