Oestology of the Skull

Question 1

What is the Anterior Fontanelle and where is it found?

Answer 1

Intersection of the inter-frontal, coronal and sagittal sutures. It is diamond-shaped

Question 2

When does the anterior fontanelle disappear?

Answer 2

At one and half years of age

Question 3

What are sutures?

Answer 3

They are an unossified membranous intervals that separate the bones of the vault

Question 4

What is the posterior fontanelle and where is it found?

Answer 4

Lies at the intersection of the sagittal and lambdoid sutures and is triangular.

Question 5

When does the posterior fontanelle fuse?

Answer 5

First year of life

Question 6

Where are many small fontanelles found on the skull?

Answer 6

The lateral aspect

Question 7

What is the clinical importance of fontanelles and sutures?

Answer 7

• Membranous Articulations/ molding during birth
• Allows brain development/ enlargement
• Access into cranium / Venus sinus/ ventricle
• Bulging : increased intracranial pressure
• Depression : dehydration
• Monitor Pulse

Question 8

What is meant by the ventricle?

Answer 8

The cavity inside the cranium

Question 9

When is the one time overlap of sutures occurs?

Answer 9

At birth

Question 10

What is the importance of molding of the neonatal skull at birth?

Answer 10

Allow diameter of the skull to become smaller, therefore easier for baby to come out during natural birth

Question 11

What would happen if there was dehydration of the skull?

Answer 11

Need to be hospitalised fro intravenous fluid

Question 12

If there was assumptions of meningitis what would be done?

Answer 12

Inject into the anterior fontanelle and extract cerebrospinal fluid very easily

Question 13

Name one difference in the size of the cranium between a newborn skull and an adult skull

Answer 13

Newborn skull has a disproportionately large cranium (portion enclosing the brain) relative to the face

Question 14

What cause increase in length of the face?

Answer 14

Growth of the mandible, maxillary sinuses, and the alveolar process of the maxilla

Question 15

What is meant by the neurocranium?

Answer 15

Bones enclosing the brain

Question 16

What is meant by the viscerocranium?

Answer 16

Facial bones

Question 17

List all the facial bones (viscerocranium)

Answer 17

Zygomatic bones
Maxillae
Nasal bones
Lacrimal bones
Vomer
Palatine bones
Inferior concha
Mandible
Sphenoid
Ethmoid

Question 18

List there facial bones which are paired

Answer 18

Zygomatic bones
Maxillae
Nasal bones
Lacrimal bones
Palatine bones
Inferior concha

Question 19

List all the facial bones that are single

Answer 19

Vomer
Mandible
Sphenoid
Ethmoid

Question 20

Are the Zygomatic bones

paired or single?

Answer 20

Paired

Question 21

Are the Maxillae bones paired or single?

Answer 21

Paired

Question 22

Are the Nasal bones paired or single?

Answer 22

Paired

Question 23

Are the Lacrimal bones paired or single?

Answer 23

Paired

Question 24

Are the Vomer bones paired or single?

Answer 24

Single

Question 25

Are the Palatine bones paired or single?

Answer 25

Paired

Question 26

Are the Inferior concha bones paired or single?

Answer 26

Paired

Question 27

Are the Mandible bones paired or single?

Answer 27

Single

Question 28

Are the Sphenoid bone paired or single in the viscerocranium?

Answer 28

Single

Question 29

Are the Ethmoid bones paired or single in the viscerocranium?

Answer 29

Single

Question 30

What is the nasal bone paired?

Answer 30

It has a suture

Question 31

What is the vomer bone part of?

Answer 31

The nasal septum

Question 32

List the bones that form the neurocranium

Answer 32

``` Single Frontal Paired parietal Paired temporal Single Occipital bone Single Sphenoid bone Single Ethmoid bone ```

Question 33

How many cranial bones are there?

Answer 33

8

Question 34

List all the single bones that form the neurocranium

Answer 34

Single Frontal Single Occipital bone Single Sphenoid bone Ethmoid bone

Question 35

List all the paired bones that form the neurocranium

Answer 35

Paired parietal | Paired temporal

Question 36

What are the features of the Norma Frontallis?

Answer 36

Nasion Glabella Supercilary Arches Supraorbital margin

Question 37

What are the foramina in the norma frontalis?

Answer 37

Supraorbital | Infraorbital

Question 38

What is found within the frontal bone?

Answer 38

Superciliary arches Supraorbital margin Glabella

Question 39

What is found within the zygomatic bone?

Answer 39

Temporal process of zygomatic bone

Question 40

What is found in the temporal bone?

Answer 40

``` Zygomatic process of temporal bone Superior and inferior temporal lines External acoustic meatus Mastoid process Styloid process ```

Question 41

What is found in the maxilla?

Answer 41

Hard Palate | Infraorbital fporamen

Question 42

What is found in the occipital bone?

Answer 42

Occipital condyle (projection inside) External occipital protuberance Superior nuchal line

Question 43

What is the name for the large projection behind the ear?

Answer 43

Zygomatic process

Question 44

Where is the pterion found?

Answer 44

2.6 cm behind and 1.3 cm above the frontozygomatic suture

Question 45

What vessel runs along the pterion? Where is it found?

Answer 45

Anterior division of the middle meningeal artery Runs underneath the pterion Found outside the duramater

Question 46

State the consequence of a traumatic blow (perhaps car crash) to the pterion?

Answer 46

The middle meningeal artery could rupture as it passes very close to the pterion. This can cause internal bleeding and an extradural haematoma.

Question 47

List the 3 divisions of the interior base of the skull

Answer 47

Anterior cranial fossa Middle cranial fossa Posterior cranial fossa

Question 48

What separates the anterior cranial fossa from the middle cranial fossa?

Answer 48

The lesser wing of sphenoid

Question 49

What separates the middle cranial fossa from the posterior cranial fossa?

Answer 49

Petrous part of the temporal bone

Question 50

State differences between male and female skulls

Answer 50

- Male skulls are heavier | - Forehead is beetle-browed

Question 51

What causes men to have more projected eyebrows (beetle-browed forehead)?

Answer 51

The frontal sinuses are larger and form more prominent superciliary arches externally