The Skull - Week 2

Question 1

what are meninges?

Answer 1

• connective tissue layers that house and support the brain
• outer layers are called dura mater
• folds of dura put tension on bone and produce features

Question 2

what are the outer layers of dura mater?

Answer 2

• outer periosteal layer follows bone
• inner meningeal layer follows major brain partitions

Question 3

dural venous sinuses

Answer 3

formed at junction of periosteal dura mater and meningeal dural folds
- venous drainage of blood from brain

Question 4

cranial nerves

Answer 4

peripheral nerves originating from the brain and brainstem

Question 5

how many cranial nerves are there?

Answer 5

12

Question 6

cranial nerve I

Answer 6

olfactory nerve

Question 7

CNI exit and function

Answer 7

• exit: cribiform plate (ethmoid)
• function: olfactory mucosa

Question 8

Cranial Nerve II

Answer 8

optic nerve

Question 9

CN II exit and function

Answer 9

• exit: optic canal (sphenoid)
• target/function: retina - vision

Question 10

Cranial Nerve III

Answer 10

oculomotor nerve

Question 11

CN III exit and function

Answer 11

• exit: superior orbital fissure (sphenoid)
• target/function: extrinsic and intrinsic eye muscles

Question 12

Cranial Nerve IV

Answer 12

trochlear nerve

Question 13

CN IV exit and function

Answer 13

exit: superior orbital fissure (sphenoid)
target/function: extrinsic eye muscle

Question 14

Cranial Nerve V

Answer 14

trigeminal nerve

Question 15

what are the divisions of the trigeminal nerve?

Answer 15

V1, V2, and V3

Question 16

CN V1 exit and function

Answer 16

ophthalmic nerve
exit: superior orbital fissure
function: cutaneous innervation of upper face

Question 17

CN V2 exit and function

Answer 17

maxillary nerve
exit: foramen rotundum (sphenoid)
function: cutaneous innervation of midface

Question 18

CN V3 exit and function

Answer 18

mandibular nerve
exit: foramen ovale (sphenoid)
function: cutaneous innervation of lower face/jaw, muscles of mastication

Question 19

Cranial Nerve VI

Answer 19

abducens nerve

Question 20

CN VI exit and function

Answer 20

exit: superior orbital fissure (sphenoid)
target/function: extrinsic eye muscle

Question 21

Cranial Nerve VII

Answer 21

facial nerve

Question 22

CN VII exit and function

Answer 22

exit: internal auditory meatus (temporal)
target/function: glands, mm of facial expression, and taste

Question 23

Cranial Nerve VIII

Answer 23

vestibulocochlear nerve

Question 24

CN VIII exit and function

Answer 24

exit: internal auditory meatus (temporal)
target/function: inner ear (balance and hearing)

Question 25

Cranial Nerve IX

Answer 25

glossopharyngeal nerve

Question 26

CN IX exit and function

Answer 26

exit: jugular foramen (occipital/temporal) target/function: parotid gland, stylopharyngeus muscle, taste

Question 27

Cranial Nerve X

Answer 27

vagus nerve

Question 28

CN X exit and function

Answer 28

exit: jugular foramen (occipital/temporal) target/function: gut, pharyngeal, and laryngeal mm, and taste

Question 29

Cranial Nerve XI

Answer 29

accessory nerve

Question 30

CN XI exit and function

Answer 30

exit: jugular foramen (occipital/temporal) target/function: trapezius and sternocleidomastoid mm

Question 31

Cranial Nerve XII

Answer 31

hypoglossal nerve

Question 32

CN XII exit and function

Answer 32

exit: hypoglossal canal (occipital) target/function: all intrinsic (most extrinsic) tongue mm

Question 33

cartoid canal

Answer 33

internal cartoid artery goes through the auditory canal in the petrous portion

Question 34

foramen spinosum

Answer 34

middle meningeal artery

Question 35

foramen lacerum

Answer 35

few vessels

Question 36

craniometrics

Answer 36

- quantitative description of skull size and shape - provides standardized protocol, comparable data - statistical evaluation of populations

Question 37

frankfort horizontal position

Answer 37

- plane is defined by three points with the skull facing to the left - right porion - left porion - left orbitale

Question 38

maximum cranial height

Answer 38

ba - b

Question 39

maximum cranial length

Answer 39

g - op

Question 40

cranial base length

Answer 40

ba - n

Question 41

basion - prosthion length

Answer 41

ba - pr

Question 42

maximum cranial breadth

Answer 42

eu - eu

Question 43

maximum frontal breadth

Answer 43

ft - ft

Question 44

bizygomatic diameter

Answer 44

zy - zy

Question 45

nasal breadth and height

Answer 45

breadth: al - al height: n - ns

Question 46

upper facial height

Answer 46

n - pr

Question 47

arachnoid mater

Answer 47

- the middle layer of your meninges that lies directly below the dura mater - thin layer that lies between dura and pia mater - no blood vessels or nerves

Question 48

pia mater

Answer 48

- the delicate, innermost membrane enveloping the brain and spinal cord - made of connective tissue and tiny blood vessels

Question 49

arachnoid granulations

Answer 49

tufts of arachnoid membrane invaginated into the dural sinuses through which cerebrospinal fluid (CSF) enters the venous system. The lesions are primarily located in the parasagittal region along the superior sagittal sinus[1], which is occasionally seen at the transverse sinus.

Question 50

arachnoid fovea

Answer 50

pits or depressions found on the endocranial surface

Question 51

pituitary gland

Answer 51

- It sits in an indent in the sphenoid bone called the sella turcica. - functions in making several horomones and is apart of the endocrine system

Question 52

sella turcica

Answer 52

depression in the sphenoid that contains the pituitary gland

Question 53

falx cerebri

Answer 53

the largest of the four partitions of the dura mater, and represents an invagination of the meningeal layer of dura into the longitudinal fissure of the brain

Question 54

crista galli

Answer 54

- a thick, midline, smooth triangular process arising from the superior surface of the ethmoid bone, projecting into the anterior cranial fossa. - It separates the olfactory bulbs, which lie on either side of it in the olfactory fossae of the cribriform plate

Question 55

dural venous sinuses

Answer 55

- a group of sinuses or blood channels that drains venous blood circulating from the cranial cavity. - sagittal sulcus

Question 56

sigmoid sulcus

Answer 56

The inner surface of the mastoid portion of the temporal bone presents a deep, curved groove, the sigmoid sulcus, which lodges part of the transverse sinus

Question 57

jugular foramen

Answer 57

- soft tissue structures: CN IX, X, and IX - located inferior to the foramen ovale

Question 58

internal jugular vein

Answer 58

x