Week 2: Head and Neck 2: Face and Skull

Question 1

What are the 3 branches of the trigeminal nerve?

Answer 1

• ophthalmic
• mandibular
• maxillary

Question 2

What are the 3 groups of muscles in the head?

Answer 2

• muscles of facial expression
• muscles of mastication
• extraocular muscles

Question 3

What are the 6 muscles of facial expression?

Answer 3

1. occipitofrontalis
2. orbicularis oculi
3. buccinator
4. orbicularis oris
5. dilators of the mouth
6. platysma

Question 4

Which nerve innervates the muscles of facial expression?

Answer 4

facial nerve (CN VII)

Question 5

What is the action of occipitofrontalis?

Answer 5

• pulls the scalp anteriorly
• wrinkles the forehead
• elevates the eyebrows
• posterior part pulls scalp posteriorly

Question 6

What is the function of orbicularis oculi?

Answer 6

closes the eyelids

Question 7

What is the action of orbicularis oris?

Answer 7

sphincter of the mouth

Question 8

What is the function of the dilators of the mouth?

Answer 8

control the aperture of mouth

Question 9

What is the function of the buccinator muscles?

Answer 9

• keep the cheek taut
• resists distension when whistling, sucking and blowing
• to pull back the angle of the mouth and to flatten the cheek area, which aids in holding the cheek to the teeth during chewing

Question 10

What is the action of platysma muscle?

Answer 10

tenses the skin of the inferior face and neck

Question 11

What are the sensory functions of the facial nerve?

Answer 11

provides innervation to the external auditory meatus, the tympanic membrane and pinner of the ear.
Also provides taste sensation to the anterior 2/3rds of tongue

Question 12

what is the tympanic membrane?

Answer 12

• a.k.a eardrum

- separates outer ear from middle ear

Question 13

Which two muscles act as dilators of the eyelid?

Answer 13

1. iris dilator muscle

2. pupillary dilator muscle

Question 14

Paralysis of the orbicularis oculi can lead to what complications?

Answer 14

• failure of eyelid closure
• ectropion of the lower eye lid (sags outward)
• lead to corneal injury due to lack of protection, dryness

Question 15

What is the function of the buccinator muscle in neonates?

Answer 15

suckling

Question 16

Which salivary glands are the largest?

Answer 16

the parotid glands

Question 17

Where is the parotid gland?

Answer 17

it occupies the interval between the mastoid process (origin of SCM) posteriorly, and the ramus of the mandible (covered by the masseter muscle), which it overlaps anteriorly

Question 18

Where does the parotid duct penetrate the buccinator muscle?

Answer 18

opposite crown of the 2nd upper molar tooth

Question 19

How do secretions from the parotid gland reach the mouth?

Answer 19

the parotid duct carries secretions - it travels over the masseter muscle to pierce the buccinator muscle and open (drain) into the mouth

Question 20

What is the name of the duct that drains saliva from the parotid gland into the oral cavity, at area of upper cheeks?

Answer 20

stensen’s duct

Question 21

where does the facial nerve divide into its 5 terminal branches?

Answer 21

in the parotid gland

the nerve lies superficially within the gland so is vulnerable to damage

Question 22

What are the five branches of the facial nerve (CN VII)?

Answer 22

1. temporal branch
2. zygomatic branch
3. buccal branch
4. marginal mandibular branch
5. cervical branch

Question 23

What structures lie within the substance of the parotid gland?

Answer 23

• facial nerve
• the retromandibular vein
• external carotid artery

Question 24

What is the retromandibular vein formed from?

Answer 24

the union of the superficial temporal vein and maxillary vein

Question 25

what are the two terminal branches of the external carotid artery called?

Answer 25

maxillary artery and superficial temporal artery

Question 26

What are the 7 anterior branches of the external carotid artery? (Some Anatomists Like Freaking Out Poor Medical Students)

Answer 26

1. superior thyroid artery 2. ascending pharyngeal artery 3. lingual artery 4. facial artery 5. occipital artery 6. posterior auricular artery 7. superficial temporal artery

Question 27

The middle meningeal artery is a branch from which artery?

Answer 27

maxillary

Question 28

What does the middle meningeal artery supply?

Answer 28

the dura mater and calvaria

Question 29

Which bones converge at the pterion?

Answer 29

temporal parietal frontal sphenoid

Question 30

What type of intracranial bleeding might result from a fracture at the pterion?

Answer 30

extradural haematoma

Question 31

What are the 4 pulses we can palpate in the face and which artery is being palpated in each case?

Answer 31

1. Temporal pulse - superficial temporal artery 2. Temporal pulse - anterior branch of superficial temporal artery 3. Carotid pulse - common carotid 4. Facial pulse - facial artery

Question 32

Where do we palpate the facial pulse?

Answer 32

angle of mandible - aligns with corner of mouth

Question 33

Where to we palpate temporal pulse?

Answer 33

either: - area anterior to ear - lateral to eyebrow at level of upper eyelid

Question 34

Where do we palpate carotid pulse?

Answer 34

lateral to upper border of thyroid and medial to anterior border of sternocleidomastoid

Question 35

What is the function of the hypoglossal nerve?

Answer 35

innervates tongue musculature

Question 36

explain the course of the hypoglossal nerve

Answer 36

- loops around internal and external carotid arteries | - runs toward tongue

Question 37

What are the orbits?

Answer 37

- eye sockets | - bilateral bone cavities in the facial skeleton, formed by 7 bones of the skull

Question 38

What 4 foramina are located in the orbits?

Answer 38

- optic canal - superior orbital fissure - infra orbital groove - infra orbital foramen

Question 39

What are the 7 extraocular muscles?

Answer 39

- superior rectus muscle - inferior rectus muscle - medial rectus muscle - lateral rectus muscle - superior oblique muscle - inferior oblique muscle - levator palpebrae superioris

Question 40

what is the function of the superior rectus muscle and which cranial nerve is it innervated by?

Answer 40

- elevates the eyeball | - supplied by CN III (Oculomotor nerve)

Question 41

what is the function of the inferior rectus muscle and which cranial nerve is it innervated by?

Answer 41

- depresses the eyeball | - supplied by CN III (oculomotor)

Question 42

what is the function of the medial rectus muscle and which cranial nerve is it innervated by?

Answer 42

- adducts the eyeball (looks towards nose) | - supplied by CN III (oculomotor)

Question 43

what is the function of the lateral rectus muscle and which cranial nerve is it innervated by?

Answer 43

- abducts the eyeball (looks laterally) | - supplied by CN VI (abducens nerve)

Question 44

what is the function of the superior oblique muscle and which cranial nerve is it innervated by?

Answer 44

- inverts (medially rotates) the eyeball | - supplied by CN IV (trochlear nerve)

Question 45

what is the function of the inferior oblique muscle and which cranial nerve is it supplied by?

Answer 45

- everts (laterally rotates) the eyeball | - supplied by CN III (oculomotor)

Question 46

what is the function of the levator palebrae superioris and which cranial nerve is it innervated by?

Answer 46

- muscle that lifts the eyelids | - supplied by CN III (oculomotor)

Question 47

What is diplopia?

Answer 47

double vision - when you look at 1 object but see 2 images

Question 48

Explain how you would examine the cranial nerves involved in eye movements

Answer 48

- oculomotor: ask patient to look medially. check that upper lid is fully retracted on upward gaze - abducens: ask patient to look laterally - trochlear: ask patient to look medially then look downwards

Question 49

What is ptosis?

Answer 49

- drooping or falling of the upper eyelid | - results from malfunction of levator palpebrae superioris

Question 50

What is horners syndrome?

Answer 50

characterised by miosis (constriction of pupil - resulting in decreased pupil size), ptosis and anhidrosis (absence of sweating of the face)

Question 51

Why does mild ptosis occur in Horner's syndrome?

Answer 51

damage to oculomotor nerve which innervates levator palpebrae superioris

Question 52

What are the 3 intraocular muscles?

Answer 52

-sphincter pupillae -dilator pupillae -ciliary muscle these muscles are WITHIN the eye

Question 53

Which intraocular muscles are supplied by the oculomotor nerve?

Answer 53

ciliary and sphincter pupillae muscles

Question 54

What is the function of the ciliary muscles?

Answer 54

changes the shape of the lens when your eyes focus on a near object

Question 55

What is the function of the dilator pupillae muscle?

Answer 55

Dilate the pupil when available light decreases

Question 56

What is the function of the sphincter pupillae muscle?

Answer 56

Constricts the pupil in bright light

Question 57

Where is the temporomandibular joint?

Answer 57

the joint is formed by the articulation between the mandibular fossa of the temporal bone and the condylar process of the mandible

Question 58

What is the function of the temporomandibular joint?

Answer 58

gliding, rotation, flexion (elevation) and extension (depression) of the mandible

Question 59

Why is dislocation of the TMJ rare?

Answer 59

the articular tubercle acts with the ligaments to prevent dislocation

Question 60

What is protrusion?

Answer 60

for the mouth to open the condylar process glides anteriorly to lie directly beneath the articular tubercle

Question 61

What are the 4 muscles of mastication?

Answer 61

1. temporalis 2. masseter 3. lateral pterygoid 4. medial pterygoid

Question 62

Where does the temporalis muscle originate and insert?

Answer 62

Origin: temporal fossa of the skull Insertion: coronoid process of the mandible

Question 63

Where does the masseter muscle originate and insert?

Answer 63

Origin: zygomatic process of the temporal bone Insertion: lateral aspect of the ramus and angle of the mandible

Question 64

Where does the lateral pterygoid originate and insert?

Answer 64

Origin: lateral aspect of the lateral pterygoid plate of the sphenoid bone Insertion: condyloid process of the mandible

Question 65

Where does the medial pterygoid originate and insert?

Answer 65

Origin: medial aspect of the lateral pterygoid plate Insertion: medial aspect of the angle of mandible

Question 66

How can the mandible move laterally?

Answer 66

due to contractions of the medial and lateral pterygoid muscles

Question 67

What are the muscles of mastication supplied by?

Answer 67

the mandibular branch of the trigeminal nerve

Question 68

Which muscles are involved in protrustion of mandible?

Answer 68

lateral pterygoid assisted by medial pterygoid

Question 69

Which muscles are involved in retraction of mandible?

Answer 69

temporalis, masseter, geniohyoid and digastric

Question 70

Which muscles are involved in elevation of mandible?

Answer 70

temporalis, masseter, medial pterygoid

Question 71

Which muscles are involved in depression of mandible?

Answer 71

gravity, digastric, geniohyoid and mylohyoid muscles