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Flashcards in Cranial nerves Deck (18)
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1
Q

What nerve innervates the muscles of mastication?

A

Trigeminal nerve (V3)

2
Q

What are the muscles of mastication?

A

3 close the jaw:

  • -masseter
  • -temporalis
  • -medial pterygoid

1 opens the jaw: lateral pterygoid

3
Q

Result of facial nerve (CN VII) lesion

A
  • -ipsilateral facial paralysis (paralysis of muscles of facial expression)
  • -inability to close eye (orbicularis oculi)
  • -loss of corneal reflex (efferent limb)

if the lesion is to the proximal facial nerve:

  • -loss of taste sensation to anterior 2/3 of the tongue
  • -hyperacusis (increased sensitivity to sound because of paralysis of stapedius muscle)
  • -disturbed lacrimation and salivation
4
Q

What is facial nerve palsy?

A

complete destruction of the facial nerve nucleus itself, or its effert fibers (the facial nerve)

5
Q

With regard to facial lesions, where would an upper motor neuron lesion be, and what would be the result?

A

Lesion of the motor cortex or connection between the cortex and the facial nucleus.

Results in contralateral paralysis of lower face.
**The forehead is spared due to bilateral UMN innervation

6
Q

What would be the result of a lower motor neuron (LMN) lesion to the facial pathway

A

ipsilateral paralysis of the upper and lower face.

7
Q

What diseases is facial nerve palsy associated with?

A
  • -Lyme disease
  • -herpes simplex
  • -herpes zoster (less common)
  • -sarcoidosis
  • -tumors
  • -diabetes
8
Q

Treatment of facial nerve palsy

A

corticosteroids

9
Q

An inability to chew would result from a lesion to what nerve?

A

Trigeminal (V3)

a lesion of this nerve would cause the jaw to deviate to the side of the lesion (side of muscle weakness) due to unopposed force from opposite pterygoid muscle

10
Q

Physical exam manifestation of a CN X lesion

A

uvula deviates away from the side of the lesion

11
Q

Physical exam manifestation of CN XII lesion

A

Tongue deviates toward the side of the lesion due to weakened tongue muscles on affected side.

(genioglossus, hypoglossus, styloglossus)

12
Q

Physical exam manifestation of CN XI lesion

A

Weakness turning head to contralateral side of lesion (Right sternocleidomastoid contracts to turn head to the left)

Shoulder droop/weakness in attempt to shrug shoulder on the side of the lesion (trapezius)

13
Q

Impairment of facial sensation would result from a lesion to what nerve?

A

Trigeminal

14
Q

The three cranial nerves that supply taste

A

7, 9, 10

15
Q

What nerve is required to say “mi”?

A

CN 7 is needed to move the lips while saying “mi”

16
Q

What nerve is needed to say “kuh”?

A

CN X is needed to raise the palate while saying “kuh”

17
Q

What nerve carries general somatic sensation from the posterior part of the upper pharynx?

A

CN IX

18
Q

gag relfex afferent, efferent?

A

CN 9, 10