Skull Osteology

Question 1

cribriform plate

Answer 1

olfactory nerve bundles (CN I)

Question 2

optic canal

Answer 2

Optic Nerve (CN II)
Ophthalmic artery

Question 3

superior orbital fissure

Answer 3

• Oculomotor Nerve (CN III)
• Trochlear N (CN IV)
• Trigeminal N, ophthalmic branch (CN V,1) : lacrimal, frontal, nasociliary branches
• Abducens N (CN VI)
• Superior ophthalmic vein

Question 4

foramen rotundum

Answer 4

Trigeminal N., Maxillary branch (CN V,2)

Question 5

foramen ovale

Answer 5

• Trigeminal N., Mandibular branch (CN V,3)
• Accessory meningeal artery
• lesser petrosal n (occasionally)

Question 6

foramen spinosum

Answer 6

• middle meningeal a/v

- meningeal branch of mandibular n (CN V,3)

Question 7

foramen lacerum

Answer 7

greater petrosal nerve crosses this space

Question 8

carotid canal

Answer 8

• internal carotid artery

- internal carotid nerve plexus

Question 9

internal acoustic meatus

Answer 9

• Facial N (CN VII)
• Vestibulocochlear N (CN V VIII)
• labyrinthine a

Question 10

jugular foramen

Answer 10

• inferior petrosal venous sinus
• Glossopharyngeal N (CN IX)
• Vagus N (CN X)
• Accessory N (CN XI)
• sigmoid venous sinus
• posterior meningeal artery

Question 11

hypoglossal canal

Answer 11

• Hypoglossal N (CN XII)

Question 12

foramen magnum

Answer 12

• medulla oblongata
• meninges
• vertebral arteries
• meningeal branches of vertebral arteries
• spinal roots of accessory nerves

Question 13

what bones make up the orbit?

Answer 13

• orbital plate of frontal bone
• greater wing of sphenoid
• lesser wing of sphenoid
• orbital plate of ethmoid bone
• lacrimal bone
• orbital plate of maxilla
• orbital plate of zygomatic bone

Question 14

sutures of the palate (and the bones forming them)

Answer 14

Medial palatine suture: btwn 2 palatine processes of maxilla

Transverse palatine suture: btwn horizontal plate of palatine bone and palatine process of maxilla

Question 15

bregma

Answer 15

• on top of head

- where sagittal suture meets coronal suture

Question 16

asterion

Answer 16

• posterolateral

- temporal, parietal, occipital meet

Question 17

pterion

Answer 17

• lateral
• meeting of frontal, parietal, temporal, GW sphenoid
• very thin, blood vessels flow underneath –> epidural hematoma if trauma here

Question 18

persistent metopic suture

Answer 18

frontal suture persists into adulthood

Question 19

fontanelle bone

Answer 19

bone forms in fontanelle

Question 20

sutural/wormian bones

Answer 20

puzzle piece-like bones formed in sutures

Question 21

inion

Answer 21

external occipital protuberance

Question 22

nuchal line

Answer 22

external occipital crest

below inion

Question 23

paranasal sinuses

Answer 23

frontal
ethmoid
maxillary
sphenoid

developed POST-NATALLY

Question 24

growth of maxillary sinus can cause

Answer 24

Maxillary sinus grows towards teeth:

• impinge nerve roots
• infection spreads from sinus to teeth (or other direction)

Question 25

mastoiditis

Answer 25

Middle ear infection. Spread due to air cells in mastoid process. Complications: - vertigo (CN VIII) - hearing loss (CN VIII) - facial paralysis (CN VII)

Question 26

arachnoid granulations

Answer 26

Structures CSF flows through. | Imprint on calvaria.

Question 27

diploic veins

Answer 27

Normal structures that may look like fractures on xray. Usually 4 on each side. Drain diploe sandwich of calvaria. Connect to nearest venous sinus.

Question 28

foramen cecum

Answer 28

tiny foramen anterior to cribriform plate

Question 29

clinoid processes

Answer 29

anterior/posterior | sphenoid bone

Question 30

parts of the sella turcica

Answer 30

- anterior clinoid processes (sphenoid) - tuberculum sellae - sella turcica (over sphenoid sinus) - dorsum sellae - posterior clinoid processes

Question 31

branches of trigeminal nerve (CN V)

Answer 31

1) ophthalmic division - superior orbital fissure - supraorbital foramen 2) maxillary division - foramen rotundum - infraorbital groove - infraorbital foramen 3) manibular - foramen ovale

Question 32

hardest bone in the body

Answer 32

petrous part of temporal bone | -contains inner ear

Question 33

arcuate eminence

Answer 33

Curved outline from anterior semicircular canal. Petrous part of temporal bone

Question 34

3 pathways after entering internal acoustic meatus

Answer 34

1) facial canal - exit via groove for greater petrosal n - parasympathetic 2) Petrotympanic fissure - to mandibular fossa - parasympathetic 3) Stylomastoid foramen - motor (CN VII: facial)

Question 35

dural venous sinuses

Answer 35

drain into jugular foramen

Question 36

tympanic canaliculus

Answer 36

where the parasympathetic nerves traveling with CN IX re-enters the skull after exiting from jugular foramen

Question 37

pterygopalatine fossa is the gateway to

Answer 37

- nose - orbit - palate - cranial base - pharynx

Question 38

can take pulse from facial artery where?

Answer 38

antegonial notch