Download THE NEUROLOGIC EXAMINATION Kelly A. Malloy, OD, FAAO

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THE NEUROLOGIC EXAMINATION
Kelly A. Malloy, OD, FAAO, Diplomate
Erin M. Draper, OD, FAAO
● The content of this COPE Accredited CE activity was prepared independently by Kelly A. Malloy and
Erin M. Draper without input from members of the optometric community.
● Kelly A. Malloy and Erin M. Draper have no direct financial or proprietary interest in any companies,
products or services mentioned in this presentation.
● The content and format of this course is presented without commercial bias and does not claim
superiority of any commercial product or service.
COURSE DESCRIPTION: A case based approach is used to highlight testing of the cranial nerves as
well as motor, sensory and coordination testing. This course focuses on the neurologic examination, and
its importance as a complement to the eye examination. Identification of associated neurologic signs and
symptoms helps with localization, diagnosis and treatment.
COURSE OBJECTIVES:
1. To review the neurologic pathways of the cranial nerves, as well as motor, sensory and
coordination function.
2. To understand when a neurologic examination is warranted to aid in the diagnosis of your patient.
3. To learn how to perform a cursory neurologic examination as a complement to the eye
examination.
4. To use the neurologic examination in combination with your eye exam to anatomically localize the
source of the problem.
5. To understand the importance of anatomic localization in arriving at an accurate and efficient
diagnosis.
6. To understand how to briefly assess the mental status of your patient.
COURSE OUTLINE:
I.
THE NEUROLOGIC EXAMINATION
a. UNDERSTANDING THE ANATOMY
i. Cranial Nerves
1. CN I
a. The olfactory nerve
i. Project to uncus of temporal lobe
2. CN II
a. The optic nerve
i. Project from retina to visual pathway in cerebral cortex
3. CN III
a. The oculomotor nerve
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i. Originates in anterior midbrain
ii. Travels through cavernous sinus and superior orbital
fissure
iii. Innervates medial, superior and inferior rectus
iv. Parasympathetics travel with CN III to cilliary body and
pupillary sphincter muscle
4. CN IV
a. The trochlear nerve
i. Originates in midbrain
ii. Crosses after leaves dorsal or posterior midbrain
iii. Travels through cavernous sinus and superior orbital
fissure
iv. Innervates superior oblique muscle
5. CN V
a. The trigeminal nerve
i. Originates in mid pons
ii. Motor division
1. To muscles of mastication
iii. Sensory division – pressure, pain and temperature
1. V1 – through superior orbital fissure (goes
through cavernous sinus)
2. V2 – through foramen rotundum (goes through
cavernous sinus)
3. V3 – through foramen ovale
6. CN VI
a. The abducens nerve
i. Originates in pons
ii. Through subarachnoid space, over clivus, into
cavernous sinus
iii. Travels through superior orbital fissure
iv. Innervates lateral rectus
7. CN VII
a. The facial nerve
i. Originates in pons
ii. Motor Division
1. Primarily facial expression
a. Upper face bilateral innervation
b. Lower face contralateral innervation
2. Parasympathetic secretomotor to lacrimal,
submandibular and sublingual glands.
iii. Sensory Division
1. From anterior 2/3 of tongue
8. CN VIII
a. The vestibulocochlear nerve
i. Originates in pons
ii. Through acoustic canal
1. Acoustic branch
2. Vestibular branch
9. CN IX
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a. The glossopharyngeal nerve
i. Originates in medulla
ii. Through jugular foramen
iii. Sensory
1. Posterior 1/3 of tongue, pharynx, tonsils and
middle ear
iv. Motor
1. Swallowing via stylopharynegeous muscle
10. CN X
a. The vagus nerve
i. Originates in medulla
ii. Through jugular foramen
iii. Longest of all cranial nerves
iv. Motor
1. Soft palate, pharynx, larynx
v. Sensory
1. Larynx, vocal cords
vi. Innervates viscera
vii. Motor parasympathetic for organs from neck to colon
11. CN XI
a. The spinal accessory nerve
i. Originates in medulla
ii. Travels into skull through foramen magnum and exits
through jugular foramen
iii. Motor
1. Sternocleidomastoid and trapezius
12. CN XII
a. The hypoglossal nerve
i. Originates in medulla
ii. Through hypoglossal canal
iii. Motor innervation of tongue
ii. Motor Pathways
1. Corticospinal and Corticobulbar Pathways
a. Originate in precentral gyrus
b. Corticobulbars project to motor neurons of the cranial nerve
nuclei
c. Become pyramids in medulla
d. Corticospinals cross in the lower medulla
iii. Sensory Pathways
1. End at the somatosensory cortex
2. Medial Lemniscal Pathway
a. Carries discriminative touch information
b. Cross in the medulla
3. Sensory Trigeminal Pathway
a. Carries proprioceptive touch
b. Cross in the medulla
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4. Spinothalamic Pathway
a. Carries pain and temperature
b. Cross in spinal cord
iv. Coordination Pathways
1. Primary motor cortex – execute movement
2. Secondary motor cortex –planning of movement
3. Cerebellum
a. Coordinates voluntary movement
b. Maintains balance and posture
c. Motor Learning – fine tuning of movements
v. Deep Tendon Reflexes
1. Two neuron reflex arc
2. Travels from muscle to brain and back to contract muscle
vi. Mental Status
1. Frontal Lobe
a. Controls speech, personality, problem solving, attention
2. Parietal Lobe
a. Controls spatial and visual perception, language construction
3. Temporal Lobe
a. Controls receptive language, organizing and sequencing,
memory and hearing
b. INTERPRETING THE NEUROLOGIC EXAMINATION
i. Look for symmetry between both sides
ii. May be subtle difference on one side as compared with the other side
iii. Need to know what is normal, and how that differs with age, etc.
c. PERFORMING THE NEUROLOGIC EXAMINATION
i. Cranial Nerve Testing
1. CN I
a. Have patient close eyes and occlude one nostril
i. Have patient smell and identify smell
1. Eg: Coffee
b. Repeat with other nostril occluded
c. Compare responses
2. CN II
a. Tested as part of comprehensive eye examination
3. CN III
a. Tested as part of comprehensive eye examination
4. CN IV
a. Tested as part of comprehensive eye examination
5. CN V
a. Sensory V
Use tissue, cotton swab, or finger
Compare both sides
i. V1 - Test sensation above eyes
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6.
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8.
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10.
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ii. V2 - Test sensation below eyes and above mouth
iii. V3 - Test sensation at mouth and below
b. Motor V (Muscles of Mastication)
i. Have patient chew
ii. Feel masseter muscle
CN VI
a. Tested as part of comprehensive eye examination
CN VII (Muscles of Facial Expression)
a. Testing upper face
i. Raise eyebrows
ii. Frown
b. Testing lower face
i. Smile
ii. Puff out cheeks
CN VIII
a. If possible – use a tuning fork
b. If no tuning fork
i. Ticking watch
ii. Rubbing fingers together
iii. Crumpling a tissue
CN IX and X (usually tested together)
a. Check for difficulty swallowing
b. Check for nasal or hoarse voice
c. Have patient protrude tongue and say “Ahhh”
i. Using penlight, watch for elevation of soft palate,
constriction of pharynx, and uvula remaining midline
ii. Abnormality would be
1. No elevation of soft palate
2. Uvula deviating to one side
CN XI
a. Testing sternocleidomastoid (SCM)and trapezius muscles
b. Peripheral lesions
i. Ipsilateral SCM weakness and ipsilateral trapezius
weakness
c. Central lesions
i. Ipsilateral SCM weakness and contralateral trapezius
weakness
d. Ask patient to shrug shoulders against examiners pushing
resistance
i. Look for symmetry, or lack thereof
e. Ask patient to turn head to right and left sides against examiners
pushing resistance
i. Look for symmetry, or lack thereof
CN XII
a. Ask patient to protrude tongue
i. It should go out straight
ii. An abnormal response is deviation to one side
1. Tongue will deviate ipsilateral to peripheral
lesion
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2. Tongue will deviate contralateral to a central
lesion
b. Ask patient to move protruded tongue side to side
1. If this is not symmetric, it may indicate mild
unilateral CN XII involvement
c. Look also for atrophy, fasciculations, (suggest LMN problem)
ii. Motor Pathways
1. Muscle Strength
a. Test for weakness of various muscles throughout the body
b. Ask patient to move against resistance
i. Flexors
ii. Extensors
2. Muscle tone / rigidity
3. Posture
4. Tremors
5. Abnormal Movements
iii. Sensory Pathways
1. Relies on subjective responses
2. Done with patients eyes closed or covered
3. Compared symmetry of response on both sides of body
4. Types of sensation tested
a. Light touch
i. Use cotton swab or fingers
b. Pain
i. Alternately use sharp and blunt end of safety pin, or
broken edge of wooden stick of cotton applicator
c. Temperature
i. Use cold surface of metal object, possibly
transilluminator
d. Vibration
e. Joint position
i. Move fingers / toes up or down and see if patient know
how they were moved
f. 2 Point Discrimination
i. Use an unraveled paper clip so it has to ends near each
other
ii. How far apart do they have to be for patient to recognize
them as 2 distinct objects
iv. Coordination / Cerebellum
1. Appendicular Coordination
a. Rapid Alternating Movements
i. Look for dysdiadochokinesis
b. Precise Finger Tapping
c. Finger-Nose Testing
i. Look for ataxia
d. Heel-Shin Testing
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2. Rhomberg Test
a. Patient asked to stand with feet together and then with eyes
closed as well
i. Look for instability / falling to the side
ii. Indicates problem with proprioception, vestibular system,
and/or midline cerebellar lesion
3. Gait
a. Ordinary Gait
b. Tandem Gait
v. Deep Tendon Reflexes
1. Tested with reflex hammer
a. Brisk reflexes: abnormality of UMN or pyrimidal tract
b. Decreased reflexes: abnormality of anterior horn, LMN, nerve or
motor end plate
vi. The Mental Status Examination
1. Assessment of consciousness (Glasgow Coma Scale)
a. Objective way of recording the conscious state of a person for
initial as well as subsequent assessment
b. Composed of three tests: eye, verbal and motor responses.
c. The three values separately as well as their sum are considered.
The lowest possible GCS (the sum) is 3 (deep coma or death),
while the highest is 15 (fully awake person).
d. Elements of the Scale (including associated score for each)
i. Eye response
1. Does not open eyes
2. Opens eyes in response to painful stimuli
3. Opens eyes in response to voice
4. Opens eyes spontaneously
ii. Verbal response
1. Makes no sounds
2. Incomprehensible sounds
3. Utters inappropriate words
4. Confused, disoriented
5. Oriented, converses normally
iii. Motor response
1. Makes no movement
2. Extension to painful stimuli (decerebrate
response)
3. Abnormal flexion to painful stimuli (decorticate
response)
4. Flexion / Withdrawal to painful stimuli
5. Localizes painful stimuli
6. Obeys commands
e. Brain injury is classified as:
i. Severe (GCS <9)
ii. Moderate (GCS 9-12)
iii. Minor (GCS = or > 13)
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2. Mini-Mental Status Examination (MMSE)
a. Scaled points based on performance
b. Maximum score: 30 points
c. Scoring
i. 27-30 : normal cognition
ii. 19-24: mild impairment
iii. 10-18: moderate impairment
iv. <9; severe impairment
d. Multiple components to test
i. Orientation to time
1. 5 possible points
2. Year, month, date, day, time
ii. Orientation to place
1. 5 possible points
2. Country, city/town, street, place, floor, etc.
iii. Registration
1. 3 possible points
2. Repeating named prompts
iv. Attention and Calculation
1. 5 possible points
2. Serial “7’s” , or spelling “world” backwards
v. Recall
1. 3 possible points
2. Recall 3 words told to patient earlier during test
vi. Language
1. 2 possible points
2. Naming common objects
vii. Repetition
1. 1 possible point
2. Speaking back a phrase
viii. Complex Commands
1. 6 possible points
d. Helping with Localization (as demonstrated through clinical cases)
i. Afferent Visual System Problem
1. Optic Neuropathy
a. Neuro retinal rim pallor
b. Relative afferent pupillary defect (RAPD)
c. Dyschromatopsia
d. Visual field loss
e. Associated with
i. Diplopia from CN III, IV, VI involvement
1. Orbit
2. Cavernous sinus
a. Also sensory loss ipsilateral distribution
of V1 and V2
2. Homonymous Hemianopia
a. Optic Tract
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i.
ii.
iii.
iv.
v.
Incongruous homonymous hemianopia
Possible small RAPD
Possible band optic disc pallor
Due to location anterior to LGN
May have other neurologic symptoms
1. Close to crus cerebri (corticospinal tract)
a. Contralateral extremity weakness
b. Optic Radiations
i. Homonymous hemianopia
ii. No RAPD, pallor or dyschromatopsia
iii. May have other neurologic symptoms
c. Occipital Lobe
i. Homonymous hemianopia
ii. No RAPD, pallor or dyschromatopsia
iii. No other neurologic symptoms
ii. Efferent Visual System Pathway
1. Anisocoria and/or Ptosis
a. Sympathetic Problem - Horner Syndrome
i. Contralateral CN IV palsy (brainstem)
ii. Ipsilateral lateral medullary syndrome (See
Wallenberg’s syndrome under diplopia)
iii. Hoarseness (phrenic nerve, vernet’s syndrome)
iv. Arm pain (Pancoast tumor)
v. Head / neck pain (carotid dissection)
vi. Contralateral CN IV palsy (Cavernous sinus)
b. Parasympathetic Problem
i. Tonic pupil
1. If Adie’s may be associated loss of deep tendon
reflexes
ii. CN III involvement (see CN III palsy below under
diplopia)
iii. Argyll-Robertson Pupil (peri-aqueductal gray)
1. Neuro-syphilis
a. Broad-based ataxic gait – posterior
columns
b. Frontal lobe – mental status changes
2. Diplopia
a. CN III Palsy
i. Midbrain
1. Contralateral hemiparesis (cerebral peduncle)
2. Contralateral tremor (red nucleus)
3. Contralateral ataxia (dentorubrothalamic)
ii. Subarachnoid/Tentorial
1. Pain
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b.
c.
d.
e.
iii. Cavernous sinus
1. CN IV, CN VI, CN V1, CN V2
2. Ipsilateral Horner syndrome
3. Chiasmal VF defect
iv. Superior Orbital Fissure / Orbit
CN IV Palsy
i. Midbrain
1. Contralateral Horner Syndrome (locus ceruleus)
2. Contralateral INO (MLF)
ii. Anterior Medullary Velum
1. Bilateral CN IV Palsy
2. Dorsal Midbrain Syndrome
iii. Superior Cerebellar Peduncle
1. Truncal Ataxia
2. Ipsilateral Dysmetria
iv. Cavernous Sinus
1. CN III, CN VI, CN V1, CN V2
2. Ipsilateral Horner Syndrome
CN VI Palsy
i. Pons
1. Ipsilateral gaze palsy
2. CN V, CN VII, CN VIII
3. Ipsilateral Horner Syndrome
4. Contralateral hemiparesis
ii. Subarachnoid / Petrous Apex
1. Papilledema, pain, CN VII
iii. Cavernous Sinus
1. CN III, IV, V1, V2
2. Ipsilateral Horner Syndrome
3. Chiasmal VF defect
iv. Superior Orbital Fissure / Orbit
1. Proptosis, RAPD, Dyschromatopsia
INO
i. Adduction Deficit
ii. Contralateral Abducting Nystagmus
iii. Can have co-existant skew deviation
iv. Lesion of MLF
1. Midbrain
a. Loss of convergence ability
2. Pons
3. Convergence spared
v. Depending on size of lesion, other brainstem pathways
may be affected
Skew Deviation
i. Vertical misalignment
ii. Higher eye intorted, lower eye extorted
iii. Graviceptive Pathway
1. Vestibular nerve
2. Lateral Medulla / vestibular nuclei
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a. Wallenberg Syndrome
i. Lateral spinothalamic tract
- Contralateral loss of pain and
temp
ii. Inferior cerebellar peduncle and
lateral spinocerebellar tract
- Ataxia
iii. Descending spinal tract and
nucleus of V
- Initial pain, then loss of pain
and temperature in ipsilateral
face
- Loss of corneal reflex
iv. Dorsal vagal nucleus,
hypoglossal nucleus, Nucleus
amgiguus
- Hoarseness, palatal paralysis,
dysphagia
v. Vestibular nuclei
- Dizziness, diplopia, vertigo,
nystagmus
3. Pons
a. Can be associated with INO
4. Midbrain
a. Can be associated with INO
b. Can be associated with Dorsal Midbrain
syndrome
i. Difficulty with upgaze
ii. Lid retraction
iii. CN IV palsy
iv. Convergence retraction
nystagmus
3. Nystagmus
a. Vertical nystagmus is never congenital
b. Can localize to:
i. Cerebellum
1. Ataxia
2. Balance issues
ii. Cervicomedullary junction
1. Chiari Malfomation
a. Downbeat nystagmus
b. Periodic alternating nystagmus
iii. Interstitial Nucleus of Cajal
1. See-saw nystagmus
2. Brainstem
3. Para-sellar tumors