Cranial Nerve Details

Question 1

What are the 2 classes of fcn for CN III?

Answer 1

GSE and GVE

Question 2

What is the GSE fcn of CN III?

Answer 2

Inf, sup, med recti mm, inf oblique and palpabrae superioris mm.

Question 3

What is the GVE fcn of CN III?

Answer 3

Parasymp to constrictor pupillae (constriction) and ciliary mm. (accomodation/focussing)

Question 4

What are some unique features of the trochlear n.?

Answer 4

• only n. that exits dorsal brain
• only n. where all lower motor neuron fibers decussate
• longest intracranial course
• smallest # of axons

Question 5

What mm. does the anterior trunk of V-1 innervate?

Answer 5

Mm. of mastication and anterior belly digastric.

- mastication mm: temporalis, masseter, lateral pterygoid, medial pterygoid

Question 6

What is the GSA innervation of V2?

Answer 6

Skin at mid-face, upper teeth, nasal and palatal mucosa

Question 7

What is the SVE innervation of CN V?

Answer 7

Mm. of mastication, anterior belly digastric, tensor tympani, mylohyoid, tensor palatini (1st arch mm.)

Question 8

What are the 3 terminal branches of V1?

Answer 8

NFL
Nasociliary
Frontal–supraorbital (lateral), supratrochlear (medial)
Lacrimal

Question 9

What is “Standing Room Only Stupid”?

Answer 9

The order of foramina:
Superior orbital fissure
Rotundum
Ovale
Spinosum

Question 10

What CN do you use to force your eyes closed?

Answer 10

CN VII

Question 11

What CN do you use when you look at bright lights?

Answer 11

CN III (sphincter pupillae)

Question 12

What CN do you use to open your eyes?

Answer 12

CN III (levator palpabrae)

Question 13

Which n. opens the pupils wide? Extra wide?

Answer 13

• Sympathetics

- Sympathetics–tarsal m. of Mueller

Question 14

What is the GVA innervation of CN VII?

Answer 14

Deep sensation from soft palate

Question 15

What is the SVA innervation of CN VII?

Answer 15

Taste from ant 2/3 tongue

Question 16

What is the GVE innervation of CN VII?

Answer 16

Motor to sublingual, submandibular, lacrimal glands, + glands of nasopharynx and hard/soft palates.

Question 17

What is the SVE innervation of CN VII?

Answer 17

Motor to mm. of facial expression, post belly digastric, stylohyoid, stapedius

Question 18

What is the GSA innervation of CN VII?

Answer 18

Small part of ear pinna sensation

Question 19

Corda tympani travels to the tongue via what n.?

Answer 19

• Lingual n.

Question 20

Lingual n. is a branch of what n.?

Answer 20

V-3

Question 21

(not good question?) What glands does the corda tympani supply? What supplies the other glands of the facial n.?

Answer 21

• Submandibular and sublingual glands

- Greater petrosal n.

Question 22

CN VII enters the skull at the ___________ and exits the skull at the ___________.

Answer 22

• Internal acoustic meatus

- Stylomastoid foramen

Question 23

What is the GVA innervation of CN IX?

Answer 23

Deep sensation from post tongue, soft palate, pharynx, mucosa of tymp cavity, post auditory tube, carotid body and sinus

Question 24

What is the SVA innervation of CN IX?

Answer 24

Taste post 1/3 tongue and adjacent pharynx

Question 25

What is the GVE innervation of CN IX?

Answer 25

Parotid salivary gland (secretomotor) | 3rd pharyngeal arch

Question 26

What is the SVE innervation of CN IX?

Answer 26

Stylopharyngeus m.

Question 27

Describe the glossopharyngeal n's path.

Answer 27

``` GLOAP: Glossopharyngeal n. Lesser petrosal n. Otic ganglion Auriculotemporal n. Parotid gland ```

Question 28

What is the GVA innervation of CN X?

Answer 28

Sensory from pharynx, esophagus, trachea, larynx, and abd viscera ("neck and down")

Question 29

What is the SVA innervation of CN X?

Answer 29

Taste buds of epiglottis and glottis

Question 30

What is the GSA innervation of CN X?

Answer 30

Sensation from small part of ear pinna, canal, and tympanic membrane

Question 31

What is the SVE innervation of CN X?

Answer 31

All mm. of pharynx (except stylopharyngeus), all mm. of the palate (except tensor veli palatini) levator palatini, all mm. of larynx, cricoid cartilage, and esophagus.

Question 32

What are sx of CN III nerve palsy?

Answer 32

- Downward and outward gaze - Dilated pupil - Ptosis (drooping of upper eyelid)

Question 33

What are sx of CN VI nerve palsy?

Answer 33

When looking one direction, palsied eye cannot gaze laterally (remains straight forward)

Question 34

What are sx of CN VII nerve palsy?

Answer 34

Bell's palsy: facial droop

Question 35

What are sx of CN XI nerve palsy?

Answer 35

Uneven shoulders (trapezius affected). Can affect SCM as well.

Question 36

What are sx of CN XII nerve palsy?

Answer 36

Tongue deviation in direction of lesion

Question 37

What CN's have parsympathetics?

Answer 37

3, 7, 9, 10

Question 38

Which CN's share the jugular foramen?

Answer 38

9, 10, 11

Question 39

Which CN's relay sensory innervation from the ear skin?

Answer 39

7, 9, 10

Question 40

CN VII and VIII share what foramen?

Answer 40

Internal acoustic/auditory meatus