Cranial Nerve Examination Flashcards

1
Q

Cranial Nerve l: Olfactory Nerve

  1. type: sensory/motor/parasympathetic? [1]
  2. function? [1]
  3. tract? [3]
  4. how to examine? [1]
A
  1. Sensory nerve
  2. Smell
  3. Olfactory cells of nasal mucosa → olfactory bulbs → pyriform cortex
  4. Ask patient if there has been any changes in their sense of smell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Cranial Nerve lI: Optic Nerve

  1. type: sensory/motor/parasympathetic? [1]
  2. function? [1]
  3. tract? [4]
  4. how to examine? [7]
A
  1. Sensory nerve
  2. Vision
  3. Retinal ganglion cells → optic chiasm → thalamus → primary visual cortex in occipital lobe
  4. Examination:
    • Optic discs with ophthalmoscope
    • Pupillary responses
    • Pupillary reflexes
    • Swinging light test
    • Visual acuity (using Snellen chart)
    • Visual fields and blind spot (tested by confrontation)
    • Eye muscles and movement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the abnormality seen in the following ophthalmoscopic image and what features lead you to this diagnosis? [4]

A
  • Papilloedema
    1. haemorrhage
    2. obscuration of blood vessels
    3. blurring of disc margins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the abnormality seen in the following opthalmascopic image and what features lead you to this diagnosis? [2]

A
  • optic atrophy/neuritis
    • pale optic disc
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is used to test visual acuity? [1]

A

Snellen Chart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe how each eye muscle moves the eye

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Cranial Nerve III: Oculomotor → the motor component:

  1. Nucleus name & location? [2]
  2. Functions? [2]
  3. Structures innervated? [5]
A
  1. Nucleus:
    • oculomotor nucleus
    • found in midbrain
  2. Functions:
    • movement of eyeball
    • lens accommodation
  3. Structures innervated:
    • inferior oblique muscle
    • superior rectus muscle
    • medial rectus muscle
    • inferior rectus muscle
    • levator palpebrae superioris muscle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Cranial Nerve III: Oculomotor → the parasympathetic component:

  1. Nucleus name & location? [2]
  2. Function? [1]
  3. Structures innervated? [2]
A
  1. Nucleus:
    • Edinger-Westphal nucleus
    • found in midbrain
  2. Function:
    • pupil constriction
  3. Structures innervated:
    • ciliary muscle
    • pupillary constrictor muscles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the diagnosis? [1]

A

Complete left oculomotor nerve palsy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Cranial Nerve IV: Trochlear

  1. type: sensory/motor/parasympathetic? [1]
  2. functions? [2]
  3. nucleus location? [2]
  4. structure innervated? [1]
A
  1. Motor nerve
  2. Functions:
    • moves eyeball
    • depresses the adducted eye
    • intorts the abducted eye
  3. Nucleus location:
    • inferior colliculus of midbrain
  4. Structure innervated:
    • superior oblique muscle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is unique about cranial nerves II and IV? [1]

A

II and IV are only nerves to decussate to contralateral side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Cranial Nerve VI: Abducens

  1. type: sensory/motor/parasympathetic? [1]
  2. functions? [1]
  3. nucleus location? [1]
  4. structure innervated? [1]
A
  1. Motor nerve
  2. Function:
    • eyeball movement to the side
  3. Nucleus:
    • pons
  4. Structure innervated:
    • lateral rectus muscles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the diagnosis? [1]

A

left abducens nerve palsy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is internuclear ophthalmoplegia, what does it result from and what condition is it commonly associated with? [3]

A
  1. Disorder of conjugate gaze which presents as failure of adduction of affected eye with nystagmus on lateral gaze in contralateral eye and can be unilateral or bilateral
  2. Results from lesion of medial longitudinal fasciculus (connects 3rd and 6th nerve nuclei)
  3. Commonly seen in multiple sclerosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe Horner’s Syndrome:

  1. symptoms? [4]
  2. causes? [9]
A
  1. Symptoms:
    • Miosis
    • Ptosis
    • Apparent enophthalmos
    • Anhidrosis
  2. Causes/Pathogenesis:
    • Results from ipsilateral disruption of cervical/thoracic sympathetic chain:
      • Congenital
      • Brainstem stroke
      • Cluster headache
      • Apical lung tumour
      • Multiple sclerosis
      • Carotid artery dissection
      • Cervical rib
      • Syringomyelia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Cranial Nerve V: Trigeminal → the sensory component:

  1. Nucleus locations? [2]
  2. Structures innervated? [4]
A
  1. Nucleus:
    • pons
    • medulla
  2. Structures innervated:
    • face → ophthalamic, maxillary + mandibular divisions
    • anterior 2/3rds of tongue
17
Q

Cranial Nerve V: Trigeminal → the motor component:

  1. Nucleus location? [1]
  2. Function? [1]
  3. Structures innervated? [4]
A
  1. Nucleus:
    • pons
  2. Function:
    • mastication
  3. Structures innervated:
    • masseter
    • temporalis
    • medial pterygoids
    • lateral pterygoids
18
Q
  1. What is the diagnosis?
  2. What nerve is affected?
  3. Who is at increased risk of developing this?
  4. How do you treat it?
A
  1. Diagnosis:
    • Herpes zoster ophthalmicus
  2. What nerve does it affect?
    • Affects V1 of trigeminal nerve
  3. Who is at increased risk?
    • Elderly
    • Immuno-compromised
  4. Treatment:
    • Oral acyclovir
19
Q

Cranial Nerve VII: Facial → the motor component:

  1. Nucleus location? [1]
  2. Function? [1]
A
  1. Nucleus:
    • pons
  2. Function:
    • innervates muscle of facial expression
20
Q

Cranial Nerve VII: Facial → the sensory component:

  1. Nucleus location? [1]
  2. Function? [1]
  3. Structures innervated? [1]
A
  1. Nucleus:
    • medulla
  2. Function:
    • taste
  3. Structures innervated:
    • anterior 2/3rds of tongue
21
Q

Cranial Nerve VII: Facial → the parasympathetic component:

  1. Nucleus location? [1]
  2. Functions? [2]
  3. Structures innervated? [2]
A
  1. Nucleus:
    • medulla
  2. Function:
    • salivation
    • lacrimation
  3. Structures innervated:
    • salivary glands
    • lacrimal glands
22
Q

How do you distinguish between an upper motor neurone lesion (UMN lesion) and lower motor neurone lesion (LMN lesion)? [2]

A
  1. Upper motor neurone lesions will present as weakness of inferior facial muscles
    • The forehead is spared
  2. Lower motor neurone lesions will present as weakness of superior and inferior facial muscles
    • = Bell’s palsy
23
Q

The Corneal Reflex:

  1. how do you test it?
  2. what nerves are you testing?
  3. what is it a test of?
A
  1. How to test it?
    • lightly touch cornea with cotton wool
  2. What nerves are you testing?
    • afferent: CN V
    • efferent: CN VII
  3. What is it a test of?
    • test of pontine function
24
Q

Cranial Nerve VIII: Vestibulocochlear

  1. type: sensory/motor/parasympathetic? [1]
  2. functions? [2]
  3. nucleus location? [2]
  4. structure innervated and tracts? [4]
A
  1. Sensory nerve
  2. Functions:
    • hearing
    • balance
  3. Nucleus location:
    • pons
    • medulla
  4. Structure innervated:
    • cochlear → auditory cortex in the temporal lobes
    • nerve endings within semi-circular canals → cerebellum and spinal cord
25
Q

Cranial Nerve IX: Glossopharyngeal → the sensory component:

  1. Nucleus location? [1]
  2. Functions? [3]
  3. Structures innervated? [3]
A
  1. Nucleus:
    • medulla
  2. Functions:
    • taste
    • proprioception for swallowing
    • blood pressure receptors
  3. Structures innervated:
    • posterior 1/3rd of tongue
    • pharyngeal wall
    • carotid
26
Q

Cranial Nerve IX: Glossopharyngeal → the motor component:

  1. Nucleus location? [1]
  2. Functions? [2]
  3. Structures innervated? [2]
A
  1. Nucleus:
    • medulla
  2. Functions:
    • swallow and gag reflex
    • lacrimation
  3. Structures innervated:
    • pharyngeal muscles
    • lacrimal glands
27
Q

Cranial Nerve IX: Glossopharyngeal → the parasympathetic component:

  1. Function? [1]
  2. Structure innervated? [1]
A
  1. Function:
    • saliva production
  2. Structure innervated:
    • salivary glands
28
Q

What is the diagnosis and how do you know? [2]

A
  1. left glossopharyngeal nerve palsy
  2. glossopharyngeal palsy causes deviation of uvula away from the side of the lesion
29
Q

Cranial Nerve X: Vagus → the sensory component:

  1. Nucleus location? [1]
  2. Functions? [3]
  3. Structures innervated? [3]
A
  1. Nucleus location:
    • medulla
  2. Function:
    • chemoreceptors
    • pain receptors
    • sensation
  3. Structures innervated:
    • chemoreceptors on carotid bodies → monitoring blood oxygen concentration
    • pain receptors → respiratory and digestive tract
    • sensation in external ear, larynx and pharynx
30
Q

Cranial Nerve X: Vagus → the motor component:

  1. Nucleus location? [1]
  2. Functions? [4]
  3. Structures innervated? [4]
A
  1. Nucleus location:
    • medulla
  2. Functions:
    • heart rate and stroke volume
    • peristalsis
    • air flow
    • speech and swallowing
  3. Structures innervated:
    • pacemaker and ventricular muscles
    • smooth muscles of the digestive tract
    • smooth muscles in bronchial tubes
    • muscles of larynx and pharynx
31
Q

Cranial Nerve X: Vagus → the parasympathetic component:

  1. Structures innervated? [2]
A
  1. smooth muscles and glands of the same areas innervated by motor component
  2. as well as thoracic and abdominal areas
32
Q

Cranial Nerve XI: Spinal Accessory

  1. type: sensory/motor/parasympathetic? [1]
  2. functions? [2]
  3. nucleus location? [1]
  4. structures innervated? [2]
  5. how to test it? [2]
A
  1. Motor nerve
  2. Functions:
    • shoulder shrugging
    • head rotation
  3. Nucleus location:
    • medulla
  4. Structure innervated:
    • sternocleidomastoid muscle
    • trapezius muscle
  5. How to test CN XI:
    • Turn your head to the side and resist my hand
    • Shrug your shoulders up and resist my hand
33
Q

Cranial Nerve XII: Hypoglossal

  1. type: sensory/motor/parasympathetic? [1]
  2. functions? [2]
  3. nucleus location? [1]
  4. structure innervated? [1]
A
  1. Motor nerve
  2. Functions:
    • speech
    • swallowing
  3. Nucleus location:
    • medulla
  4. Structure innervated:
    • tongue
34
Q

What is the diagnosis and how do you know? [2]

A
  1. left-sided hypoglossal nerve palsy
  2. tongue deviates towards the side of the lesion
35
Q

Multiple Cranial Nerve Syndromes

What cranial nerves would be affected by a lesion in the:

  1. cavernous sinus? [5]
  2. superior orbital fissue? [4]
  3. cerebellopontine angle? [3]
  4. jugular foramen? [3]
  5. bulbar/pseudobulbar palsy? [4]
A
  1. Cavernous sinus?
    • III
    • IV
    • V (1st and 2nd divisions)
    • VI
    • Horner’s syndrome
  2. Superior orbital fissure?
    • III
    • IV
    • V (1st division)
    • VI
  3. Cerebellopontine angle?
    • V
    • VII
    • VIII
  4. Jugular foramen?
    • IX
    • X
    • (and XI)
  5. Bulbar/pseudobulbar palsy?
    • IX
    • X
    • XI
    • (and XII)