2 - Skull, Scalp, Superficial Face and Neck

Question 1

What is the name of the structure that surrounds the brain? What is the top of this structure called?

Answer 1

The neurocranium, the top of which is called the calvaria (skullcap).

Question 2

What is the name for the skeleton of the face?

Answer 2

Viscerocranium.

Question 3

What is the anatomical position of the head?

Answer 3

When the orbitomeatal plan is horizontal.

Question 4

What are the bones of the skull?

Answer 4

Parietal (2), frontal, occipital, temporal (2), sphenoid, and ethmoid bones.

Question 5

What is the name of the junction between the cranial and sagittal suture?

Answer 5

Bregma.

Question 6

What is the H-shaped suture junction on either side of the head called? What is it’s significance?

Answer 6

Pterion.

70% of people have a blood vessel that runs deep to it called the middle meningeal artery which supplies the dura mater.

Fractures here can injure this artery and cause the dura mater to be stripped away, resulting in a epidural hematoma.

Question 7

What is the name for the junction of the nasal bones with the frontal bone?

Answer 7

The nasion.

Question 8

Name the term that describes the membranous intervals between the cranial bones of a newborn? What is their function.

Answer 8

Fontanelle - allows bones to move as the baby’s head passes through the birth canal.

Question 9

Describe type I, II, and III Le Fort fractures.

Answer 9

Type I: just bone of upper jaw

Type II: Maxila broken off

Type III: Maxilla and zygomatic bone detached (viscerocranium separated from neurocranium).

Question 10

What are the layers of the scalp from superficial to deep?

Answer 10

Skin, connective tissue (highly innervated and many blood vessels), aponeurosis, loose connective tissue, and pericranium.

Question 11

The epicranial aponeurosis is also called the ______ _______ and connects the bellies of the ______ and ______.

Answer 11

Also called the galea aponeurotica.

Connects the bellies of the frontalis and occipitalis.

Question 12

What scalp layer facilitates the spread of infection?

Answer 12

The loose connective tissue, because it separates easily from the other layers and can allows infections to be transmitted along blood vessels.

Question 13

If a scalp wound gapes, what layer has the wound most likely penetrated?

Answer 13

The epicranial aponeurosis, because it’s muscle bellies will pull back and contract, causing the wound to gape.

Question 14

Why do scalp wounds bleed profusely?

Answer 14

Because the fibrous connective tissue doesn’t allow the vessels to contract and seal off to stop the bleeding.

Instead they are held open by the tissue.

Question 15

Facial muscles differ from other muscles in the body because they insert into _____?

Answer 15

The skin.

This allows us to make facial expressions.

Question 16

What innervates the muscles of facial expression (motor)? Where is it located and what is its path?

Answer 16

The facial nerve (cranial nerve VII)

Emerges through stylomastoid foramen (part of temporal bone) and gives off posterior auricular branch before it goes into the parotid gland and branches into other divisions to go to the other muscles of facial expression.

Question 17

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

Answer 17

Tell Ziggy Bob Marley Called

Temporal 
Zygomatic 
Buccal 
Marginal mandibular 
Cervical

Question 18

What happens to the muscles of facial expression is cranial nerve VII (facial nerve) is injured distal to the stylomastoid foramen?

Answer 18

Bells palsy.

Droopy, sagging face.

Question 19

What nerve innervates the skin of the face and scalp (sensory)? What dermatomes does it correspond with?

Answer 19

The trigeminal nerve (cranial nerve V).

C2 and C3 (there is no C1 dermatome).

Question 20

Why is the trigeminal nerve called the triple twin? What are the names of the branches?

Answer 20

There is one nerve on each side of the pons, and each has three branches:

V1: Opthalmic (along frontal bone)
V2: Maxillary (maxilla)
V3: Mandibular (lower jaw and temporal bone)

Question 21

What is trigeminal neuralgia (Tic Douloureux)?

Answer 21

Sudden, extreme pain from a region of the face.

Patient will wince, causing the “tic”

Question 22

What is the path of the trigeminal nerve? What houses the nerve cell bodies? What type of neuron are they?

Answer 22

Emerges from the brainstem at mid-pons level.

Trigeminal ganglion houses cell bodies of sensory neurons. These bind sensory info in from the face and are comparable to the DRG . (also pseudounipolar).

Question 23

What superficial branches does the external carotid artery give off to the face and scalp?

Answer 23

Facial artery, superficial temporal artery, and the transverse facial artery.

Question 24

What superficial branches does the internal carotid artery give off to the face and scalp?

Answer 24

The supratrochlear artery and the supraorbital artery.

Question 25

Describe the location and branching of the facial artery (branch of the external carotid artery).

Answer 25

Palpable anterior to the masseter m.

Gives off superior and inferior labial branches and then becomes the angular artery.

Question 26

What vein feeds the facial vein and where is it located in relation to the corresponding artery?

Answer 26

The angular vein drains into the facial vein, they are located posterior to the artery.

Question 27

What two facial veins meet to drain into the retromandibular vein?

Answer 27

The superficial temporal vein and the maxillary vein.

Question 28

The posterior branch of the superficial temporal vein and the auricular vein meet to drain into the _______?

Answer 28

External jugular vein, which is superficial to the sternocleidomastoid muscle

Question 29

The anterior branch of the superficial temporal vein meets the facial vein to drain into the ______?

Answer 29

Internal jugular vein, which is deep to the sternocleidomastoid muscle.

Question 30

The facial vein communicates with the ____ ____ vein, which drains into the ______?

Answer 30

Superior opthalmic vein, which drains into the cavernous sinus.

Question 31

How could an infection on the face spread to the meninges and brain within the cranial cavity?

Answer 31

Because the veins don’t have valves and the blood can therefore flow in the opposite direction.

Question 32

What is the danger triangle? Why did it get this name?

Answer 32

The nose and the upper lip.

Infection here can get from the face to the interior of the cranial cavity.

Question 33

What is the function of the external ear? What it is composed of?

Answer 33

Collect sound waves.

Composed of skin and elastic cartilage.

Question 34

Describe the anatomy of the middle ear. What are its components? What is their function?

Answer 34

An air filled chamber with auditory oscicles: the malleus, incus, and stapes.

These mechanically transfer energy from the typanic membrane to the oval window on the inner ear.

Question 35

What are the two muscles of the middle ear and their functions? What innervates each?

Answer 35

1. Stapedius: connects to the stapes and holds it steady to prevent excessively loud sounds (innervated by facial nerve - CN VII)
2. Tensor Tympani: attaches to the malleus and decreases the amplitude of the oscillations to prevent overly loud sounds (innervated by facial nerve - CN VII)

Question 36

How might injury to the facial nerve effect the function of the ears?

Answer 36

Sounds may be overly loud. This is because the facial nerve innervates the stapedius and the tensor tympani, which both function to decrease sound intensity.