Transcript Cranial Nerves

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Clinical Assessment
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The “FACE” of Cranial Nerves
J Carley MSN, MA, CNE
Fall 2009
I Olfactory
II Optic
III Oculomotor
IV Trochlear
V Trigeminal
VI Abducens
VII Facial
VIII Acoustic
IX Glossopharyngeal
X Vagus
XI Spinal Accessory
XII Hypoglossal
Cranial Nerves
Cranial Nerves
 When assessing the cranial nerves, there are 3 items
the examiner must know:
 Function (Motor, Sensory, Mixed)
 Testing
 Signs of Dysfunction
Cranial Nerves
O O
O
T
T
A
F
A
G
 CN I – Olfactory Nerve
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Function: special sensory
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Testing:
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Use 2-3 vials of familiar odors
Test one nostril at a time with patient’s eyes closed
Use least irritating scent first and allow the patient to rest in
between vials
Signs of Dysfunction: anosmia
V
S
H
Cranial Nerves
O O
 CN II – Optic Nerve
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Function: special sensory
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Testing:
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Snellen Eye chart
Fundus Exam
Visual fields via confrontation
Pupillary Light reflex
Signs of Dysfunction
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Blindness
Loss of pupillary constriction (sensory)
O
T
T
A
F
A
G
V
S
H
Cranial Nerves
O O
O
T
 CN III – Occulomotor Nerve
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Function: somatic & visceral motor
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Testing:
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Six Cardinal Fields of Gaze
Pupillary Light reflex: (motor)
Accommodation
Signs of Dysfunction:
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Eye turned down & out w/ ptosis
Mydriasis, Loss of accommodation, Diplopia
T
A
F
A
G
V
S
H
Cranial Nerves
 CN IV – Trochlear Nerve
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Function: somatic motor
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Testing:
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Six Cardinal Fields of Gaze
Signs of Dysfunction:
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Vertical diplopia
Excycodeviation of the eye
O O
O
T
T
A
F
A
G
V
S
H
Cranial Nerves
O O
 CN V – Trigeminal Nerve
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Function:
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Branchial motor – mastication
General Sensory – sensory to the face
O
T
T
A
F
A
G
V
S
H
Cranial Nerves
O O
O
 CN V – Trigeminal Nerve
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Testing:
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Sharp & light touch over the three divisions
Corneal Blink Reflex (sensory)
Clinch teeth & Jaw Jerk
Signs of Dysfunction:
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Weakness
Hemianesthesia
Absent Corneal Blink Reflex
T
T
A
F
A
G
V
S
H
Cranial Nerves
O O
 CN VI – Abducens Nerve
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Function: somatic motor
Testing:
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Six Cardinal Fields of Gaze
Signs of Dysfunction:
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Horizontal diplopia
Medial deviation of the eye
O
T
T
A
F
A
G
V
S
H
Cranial Nerves
O O
 CN VII – Facial Nerve
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Function:
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Branchial motor – facial muscles
Visceral motor – glandular fcn
General Sensory – skin of the auricle
Special Sensory - taste
O
T
T
A
F
A
G
V
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H
Cranial Nerves
O O
O
T
T
 CN VII – Facial Nerve
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Testing:
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Branchial motor component: facial expression
Special Sensory: taste to the anterior 2/3 of tongue
Signs of Dysfunction:
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Hemiparesis
Dry eye
Lagophthalmos
Dry mouth
Loss of taste
A
F
A
G
V
S
H
Cranial Nerves
O O
O
T
T
A
F
A
 CN VIII – Acoustic
(Vestibulocochlear) Nerve
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Function: special sensory
Testing: hearing tests: Rinne, Weber, Audiology, whisper,
fingertips
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Signs of Dysfunction:
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Vertigo
Nystagmus
Disequilibrium
Sensorineural deafness
G
V
S
H
Cranial Nerves
O O
O
T
T
A
F
A
G
V
 CN IX – Glossopharyngeal Nerve
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Function:
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Branchial Motor – elevation of pharynx during swallowing &
speech
Visceral Motor – parotid gland fcn
Visceral Sensory – communication between carotid body & sinus
General Sensory - tongue
Special Sensory - taste
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H
Cranial Nerves
O O
O
T
T
A
F
 CN IX – Glossopharyngeal Nerve
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Testing:
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Branchial Motor: swallowing
General Sensory: gag reflex
Special sensory: taste of posterior 1/3 of tongue
A
G
V
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H
Cranial Nerves
O O
O
T
T
A
F
 CN IX – Glossopharyngeal Nerve
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Signs of Dysfunction
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Dysphagia
Dry mouth
Loss of taste
Loss of gag reflex
TYPICALLY, IX and X are
tested together
A
G
V
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H
Cranial Nerves
O O
O
T
T
A
F
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G
 CN X – Vagus Nerve
Function:
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Branchial Motor – deglutition & phonation
Visceral Motor – smooth muscles of the thoracic & abdominal
viscera
Visceral Sensory – thoracic & abdominal viscera
General Sensory – external ear
TYPICALLY, IX and X
are tested together
V
S
H
Cranial Nerves
O O
O
T
T
A
F
A
G
V
 CN X – Vagus Nerve
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Testing:
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Branchial motor: swallowing, gag reflex, soft palate elevation with uvula
remaining while saying “Ah”
Signs of Dysfunction:
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Dysphagia
Hoarseness
Uvula deviation
S
H
Cranial Nerves
O O
O
T
T
A
 CN XI – Spinal Accessory Nerve
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Function: somatic motor
Testing: Resisted shoulder elevation & head rotation
Signs of Dysfunction:
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Atrophy & Weakness
Fasciculations
Neck or shoulder deviation
F
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G
V
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H
Cranial Nerves
O O
O
T
T
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 CN XII – Hypoglossal Nerve
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Function: somatic motor
Testing:
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Stick out tongue
Press tongue against check while palpating to test muscle strength
Articulation of hard consonants: ‘L’, ‘T’, ‘D’, & ‘N’
Signs of Dysfunction:
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Atrophy & Weakness
Deviation
Dysarthria
H