Cranial Nerves: Motor Flashcards Preview

Clinical Human Anatomy: Head and Neck > Cranial Nerves: Motor > Flashcards

Flashcards in Cranial Nerves: Motor Deck (48):
1

What is CN III?

Oculomotor

2

Where is the location of neuron cell bodies of CN III?

Upper Midbrain--oculomotor nucleus

3

What is the passage of CN III through the skull?

Superior Orbital Fissure --Sphenoid bone

4

Where does the oculomotor nerve emerge?

near median plane at junction of midbrain and pons-->cavernous sinus--> superior orbital fissure

5

Where does the rectus m. originate?

common tendinous ring---oculomotor nerve ends up here

6

Levator palpebrae innervated by:

Oculomotor III

7

Superior Rectus m. innervated by:

Oculomotor III

8

Inferior Rectus m innnervated by:

Oculomotor III

9

Medial Rectus m. innervated by:

Oculomotor III

10

Inferior Oblique m. innervated by:

Oculomotor III

11

Oculomotor nerve palsy

causes ptosis = eyelid droop due to paralysis of levator palpebrae muscle

12

Ptosis

paralysis of levator palpebrae~ eyelid droop

13

What is the resting position of the eye?

Down and out when oculomotor isn't working---when superior oblique and lateral rectus m. aren't working

14

CC: pupil is fixed and dialated

Oculomotor III is out

15

A cavernous sinus injury causes damage to what cranial nerve?

CN III

16

An aneurysm of posterior cerebral or superior cerebellar artery causes damage to which cranial nerve?

CN III

17

CN IV

Trochlear

18

Function of trochlear nerve?

somatic motor--eye movement

19

Location of neuron cell body of Trochlear nerve

Lower midbrain: trochlear nucleus

20

Where does trochlear nerve pass through skull

Superior Oribital fissure: sphenoid bone

21

Where does the trochlear nerve emerge from midbrain?

from dorsal aspect of midbrain

22

What is the only nerve to emerge dorsally from the skull?

Trochlear nerve

23

What structure does the trochlear nerve innervate?

Superior oblique muscle

24

What happens when the Trochlear nerve is injured?

Can't look down when eye is adducted which is called diplopia

25

What causes injury to trochlear nerve?

cavernous sinus injury

26

What is CN VI

Abducent

27

What is the fnx f CN VI?

somatic eye movement

28

Location of NCB of Abducent?

Pons--abducent nucleus

29

How does the Abducent nerve exit the skull?

sphenoid bone--superior orbital fissure

30

What is the route of the Abducent nerve?

emerges near medial plane at jnx of pons and medulla--> through the cavernous sinus and superior orbital fissure--> through common tendinous ring

31

What structure does the Abducent nerve innervate?

Lateral rectus muscles

32

What causes horizontal diplopia (double vision)

Abducent nerve (VI)

33

What causes impaired eye abduction?

Abducent nerve damage VI

34

Which way does the eye turn when the Abducent nerve is damaged?

Eye turns medially~ medial rectus muscle out)

35

What causes injury to Abducent nerve VI?

Cavernous sinus injury and fracture to base of skull

36

What nerve is CN XI?

Accessory nerve

37

Where is the location of neuronal cell bodies of CN XI?

Spinal Cord: anterior horn of cervicle region

38

Where does the Accessory nerve pass through the skull?

Rootlets (intermediate in position of exit from sp cd) via foramen magnum
--exits via jugular foramen

39

What structures are innervated by the Accessory nerve?

SCM and and Trapezius

40

What kind of injury would cause damage to accessory XI

neck laceration

41

Special part of CN XI

spinal root represents CN XI in it's entirety, cranial roots emerge from medulla but those are part of CN X

42

What nerve is CN XII?

Hypoglossal nerve

43

The location of the NCB of CN XII?

Medulla--hypoglossal nucleus

44

Where does the CN XII pass through the skull?

Occipital bone--hypoglossal canal

45

What is the route of CN XII?

Emerges from sides of medulla anterior to olives--> passes through hypoglossal canal--> curves forward near angle of mandible superior to ansa cervicalis to enter tongue

46

What structures does hypoglossal XII innervate?

All intrinsic tongue muscles
All extrinsic tongue muslces except Palatoglossus (CN X)

47

What happens to tongue when there is a peripheral lesion in Hypoglossal CN XII?

tongue deviates towards side of injury
--lick your wounds

48

What would cause an injury to hypoglossal CN XII

Neck laceration