Cranial Nerve Assessment is a crucial step in neurological assessment. By following the simple theoretical aspects it can be made on your fingertips....here is an try to make the stuff easier for you....

1. CRANIAL NERVE
ASSESSMENT
Dr. PAWAN SHARMA (PT)
M.P.T. (NEURO)
ASSISTANT PROFESSOR,
SHRI U.S.B. COLLEGE OF PHYSIOTHERAPY
ABU-ROAD, RAJASTAHAN
Email- pawan.physio2011@gmail.com
Contact- 07727989353

2. IV Trochlear
III Oculomotor
VII Facial
VI Abducens
V Trigeminal
CEREBRAL
HEMISPHERE
MIDBRAIN
PONS
MEDULLA
CRANIAL NERVES
II Optic
I Olfactory
VIII Vestibulo-
cochlear
XII Hypoglossal
XI Accessory
X Vagus
IX Glossopharyngeal
CRANIAL NERVES
2

3. CRANIAL NERVES
 The 12 pairs of cranial nerves are part of the
peripheral nervous system.
 The Roman numeral is based on descending
order of the cranial nerve's attachment to the
CNS.
 As a rule, cranial nerves do not cross in the
brain.
 Cranial nerves may be sensory, motor both
somatic or parasympathetic, or have mixed
function.
General Characteristics:
CRANIAL NERVES
3

4. REMEMBER ME…
 SOME
 SAYS
 MONEY
 MATTERS
 BUT
 MY
 BROTHER
 SAYS
 BIG
 BRAIN
 MATTERS
 MOST
S-SENSORY
M- MOTOR
B- BOTH
All in
sequence
CRANIAL NERVES
4

5. CN I - OLFACTORY
• ORIGIN: Cerebral hemisphere
• INNERVATION: Nasal mucous
membranes.
• FUNCTION: Sense of smell
• DYSFUNCTION: Anosmia
CLINICAL EVALUATION
• Use non-noxious aromatic
substances, i.e. coffee, lemon,
garlic, etc.
• Test each nostril separately.
• Mark if any abnormality noted
CRANIAL NERVES
5

6. CN II – OPTIC NERVE
• VISUAL ACUITY: Snellen
chart for distant vision,
Jaegers chart, newspaper or
fingers for near vision.
• VISUAL FIELDS:
Confrontation.
• FUNDI AND OPTIC DISCS:
Visualization of the termination
of the optic nerve by looking
through pupil with
ophthalmoscope.
CRANIAL NERVES 6

7. CN II – OPTIC NERVE(cont..)
 Tested by-
1. Visual acuity
2. Color vision
3. Visual field
CRANIAL NERVES
7
Near field
Far field
Color
matching
Confrontation
test

8. CN II – OPTIC NERVE(cont..)
 Visual acuity-
 Snellen chart(Far vision)
◦ Chart is placed at 20 feet or 6
meter and patient is asked to
read it
◦ The formula is d/D
 Where d is 6 meter and D is
the distance from which he can
read it clearly
 Normal is 6/6 or 20/20
 Jaegers chart(Near vision)
◦ Paragraphs are printed in
successive coarser type with
0 is finest and 7 is biggest
◦ Patient is asked to read
through the hole
CRANIAL NERVES
8

9. CN II – OPTIC NERVE(cont..)
 Color vision-
◦ Checked by asking to
match different colors
• Day or night blindness
can be assessed
• Visual field-
 Confrontation test
 Peripheral visual fields-
 Goldmann Perimeter
CRANIAL NERVES 9

10. SPECIFIC DYSFUNCTIONS
• Blurred vision or complete blindness.
• Ipsilateral vision loss - Optic atrophy, retinal/optic
nerve lesions, trauma.
• Visual loss (one or both eyes) - Optic chiasm or
occipital lobe lesions.
• Hemianopia - (loss of half of visual field in one or
both eyes) - Lesions of optic chiasm, tracts, or
radiations.
• Cortical blindness - Lesion of occipital cortex
bilaterally, pupil reflexes intact.
• Papilledema - Optic nerve tumor, venous
obstruction, chronic increased ICP.
• Optic atrophy - MS, optic neuritis, increased ICP.
• Scotomas- (Abnormal blind spots on visual fields)
- optic neuritis or atrophy.
CRANIAL NERVES
10

11. CN III – OCULOMOTOR NERVE
 ORIGIN: Midbrain
 INNERVATION: EOM's;
eyelid; ciliary; and sphincter of
iris.
 FUNCTION: Eye movement
inward (medially), upward,
downward, and outward; pupil
Constriction, shape and
equality; elevates upper eyelid;
accommodation reflex.
 DYSFUNCTION: Unable to
look up, down, or medial
(dysconjugate gaze); ptosis,
pupil dilatation - bilateral or
ipsilateral, and loss of
accommodation reflex.
CRANIAL NERVES
11

12. CN III – OCULOMOTOR
NERVE(cont..)
• Observe for eye opening and
symmetry.
• Direct light response - brisk,
sluggish, or non-reactive.
• Consensual response -
present or absent.
• Pupil size and shape.
• Accommodation.
• Extra ocular movement
(EOM's) (Abducens).
CRANIAL NERVES
12

13. CRANIAL NERVE FUNCTION & MUSCLE
INNERVATION
RELATIVE TO EYE MOVEMENT
Superior rectus
CN III
Inferior oblique
CN III
Lateral rectus
CN VI
Medial rectus
CN III
Superior oblique
CN IV
Inferior rectus
CN III

14. CN IV – TROCHLEAR NERVE
 ORIGIN: Midbrain
 INNERVATION: Superior
oblique muscle.
 FUNCTION: Down and
inward movement of the
eye.
 DYSFUNCTION: Loss of
downward, inner
movement of eye,
dysconjugate gaze.
CRANIAL NERVES 14
SUPERIOR OBLIQUE MUSCLE

15. CN VI – ABDUCENS NERVE
 ORIGIN: Pons
 INNERVATION: Lateral
rectus muscle.
 FUNCTION: Outward,
lateral movement of eye.
 DYSFUNCTION: Loss of
lateral eye movement,
dysconjugate gaze.
CRANIAL NERVES 15
Clinical evaluation of CN III, IV, VI
•Extraocular movements (EOM's)
•CN IV (Trochlear) and CN VI tested with CN III (Oculomotor)
LATERAL RECTUS
MUSCLE

16. CN V – TRIGEMINAL NERVE
 ORIGIN: Pons. The sensory
nucleus extends from the
pons to the midbrain, and also
to the medulla and spinal
cord.
 INNERVATION: Three
branches of CN V:
Ophthalmic, maxillary, &
mandibular.
 Motor innervation to
masseter & temporal
muscles.
 Sensory innervation to skin &
mucous membranes in head;
teeth, tongue, external
auditory canal, and cornea.
CRANIAL NERVES
16

17. CN V – TRIGEMINAL NERVE(cont..)
 FUNCTION: Sensation of
pain, touch, hot, & cold; motor
movement of masseter &
temporal muscles.
 DYSFUNCTION: Loss of
sensation - if affecting all
three branches, indicative of
peripheral injury.
 Brainstem or upper cervical
cord injury may result in loss
of sensation to one or more
branches of the trigeminal
nerve.
 Loss of corneal reflex.
CRANIAL NERVES
17

18. CN V – TRIGEMINAL NERVE(cont..)
 Paresthesia and/or severe
pain indicative of nerve
compression or irritation
(Trigeminal neuralgia)
 Deviation of jaw towards the
same side, loss of sensation.
 Inability to bite down and
chew, inability to close jaw.
 Chewing, speaking, washing
face, cold water, may
precipitate the
attack…TRIGGER POINT
CRANIAL NERVES
18

19. CN V – TRIGEMINAL
NERVE(cont..)
 Tic douloureux or
trigeminal neuralgia
 Paroxysmal attacks of
severe, short, sharp, stabbing
pain affecting one or more
branch of the nerve.
 Most excruciating pain
known (?)
 Caused by inflammation of
nerve
 In severe cases, nerve is cut;
relieves agony but results in
loss of sensation on that side
of the face
CRANIAL NERVES 19

20. TESTING TRIGEMINAL NERVE
o Sensation-
o Checked by extroceptive
modalities like superficial pain,
thermal, light touch over jaw,
cheeks, and forehead.
o Motor examination-
o Muscle power of masticatory
muscle namely the masseter
and temporalis.
o Inability to raise, depress,
protrude, retract and deviate
the mandible
o Jaw deflected toward same
side
CRANIAL NERVES
20

21. TESTING TRIGEMINAL NERVE
 Jaw jerk-
o Ask the patient to relax
jaw. Place finger on the
chin and tap it with
hammer.
o closing of mouth is the
response
o Brisk is normal
o Exaggerated is
pathological
◦ Corneal reflex-
o Cornea is touched with wisp
of wet cotton
o Response is closing of both
eyes
o Afferent- ophthalmic div of
VI nerve
o Efferent- Facial nerve CRANIAL NERVES
21

22. CN VII- FACIAL NERVE
 ORIGIN: Pons & medulla.
 INNERVATION: Anterior
two-thirds of tongue; facial
muscles, scalp, ear, and
neck.
 FUNCTION:
 Control of facial muscles
(expressions)
 Motor limb of blink &
corneal reflex
 Secretion of salivary &
lacrimal glands
 Sensation of taste, anterior
two-thirds tongue.
CRANIAL NERVES
22

23. CN VII- FACIAL NERVE(cont..)
 Motor-
◦ Facial asymmetry - Ipsilateral weakness/paralysis, right or left,
indicative of damage to motor nucleus or peripheral component
(lower motor neuron lesion) EX: Bell's palsy
◦ Contralateral weakness/paralysis of lower face indicative of
Contralateral motor cortex damage (upper motor neuron lesion)
or hemispheric lesion, i.e. massive CVA.
◦ Bilateral weakness or paralysis , E.g. myasthenia gravis or
Guillian Barre.
 Parasympathetic-
◦ Loss or excessive tearing or salivation
• Sensory-
◦ Loss of taste from anterior 2/3
 Combined problem-
◦ speech difficulty and drooling/difficulty handling food
CRANIAL NERVES
23

24. CN VII- FACIAL NERVE(cont..)
 CLINICAL EVALUATION
o MOTOR FUNCTION:
o Observe for facial symmetry
o Flattening of nasolabial fold
o Ask patient to wrinkle
forehead, puff cheeks, smile,
show teeth, close eyes
against resistance, and
whistle.
o Wrinkle forehead- Frontalis
o Close eye- orbi oculi
o Purse lip- Buccinator
o Show teeth- Orbi oris
CRANIAL NERVES
24

25. CN VII- FACIAL NERVE(cont..)
 SENSORY FUNCTION:
• Test each side of tongue
separately.
• Test for sweet (tip of
tongue); sour (sides of
tongue); salty (over most of
tongue, but concentrated on
sides).
• Give sip of water between
tastes.
• Prevent flowing it to the
posterior aspect of tongue
• Reflex-
• Corneal reflex
• Glabellar reflex- Parkinson's
disease
CRANIAL NERVES
25

26. CN VII- FACIAL NERVE(cont..)
Guess your
observation
CRANIAL NERVES 26

27. BELLS PALSY
• Bell’s palsy: paralysis of
facial muscles on affected
side and loss of taste
sensation
• Caused by herpes simplex
I virus, trauma,
• Lower eyelid droops
• Corner of mouth sags
• Eye cannot be completely
closed (dry eye may occur)
• Lacrimation is seldom
affected
• Condition my disappear
spontaneously without
treatment
 Bells phenomenon-
Upward and outward
movement of eye
CRANIAL NERVES
27

28. CN VIII – VESTIBULOCOCHLEAR
NERVE
 ORIGIN: Pons and medulla
 INNERVATION:
◦ Cochlear - ear
◦ Vestibular - ear
 FUNCTION:
◦ Cochlear - Hearing
◦ Vestibular - Balance,
maintenance of body
position, and proprioception.
◦ Rule out for presence of
wax, pus, blood or foreign
body Before testing
CRANIAL NERVES
28

29. COCHLEAR NERVE
 Rinne’s test-
◦ For comparing bone and air
conduction
◦ Tuning fork placed at the
mastoid till the sound stop
being heard
◦ Then is placed in front of
ear to be tested
◦ +ve Rinne test i.e. air and
bone both are retained
◦ -ve Rinne test i.e. air is lost
but bone is
retained(conductive
deafness)
◦ If both are lost i.e.
sensorineural deafness
◦ BERA TEST CRANIAL NERVES
29

30. COCHLEAR NERVE(cont..)
 Weber's test-
◦ Evaluates lateralization
◦ Use vibrating tuning fork on
top of patient's head, ask
patient where he hears it
(one or both sides).
◦ Normally heard equally on
both the sides
◦ If one ear is occluded then
it acts like a resonating
chamber and hear more on
that side
◦ Conductive deafness-
involved side
◦ Sensorineural- Uninvolved
side
CRANIAL NERVES
30

31. VESTIBULAR NERVE
 Look for Vertigo,
Nystagmus, loss of balance
 NYLEN-BARANY
MANEUVER
◦ Patient lie down supine
with head off the bed
◦ 45 degree extended
◦ Lateral flexion to the
same side produces
Nystagmus
• Other tests are
• caloric test(cows)
• Galvanic test
• Rotation test
CRANIAL NERVES
31

32. CN VIII – VESTIBULOCOCHLEAR
NERVE
 DYSFUNCTION (Cochlear)
◦ Unilateral deafness
◦ Loss of sound appreciation
◦ Tinnitus
◦ (Rinne Test) AC >BC is
normal
◦ both diminished
indicative of nerve
damage
◦ BC> AC middle ear
disease.
◦ (Weber Test)
◦ Lateralization to good
ear is nerve damage,
◦ lateralization to bad
ear is, middle ear
CRANIAL NERVES 32

33. CN VIII – VESTIBULOCOCHLEAR
NERVE
 DYSFUNCTION
(VESTIBULAR)
◦ Vertigo
◦ Balance disturbances
 Vestibular branch normally
not tested unless patient
gives history of vertigo or
balance Disturbance
history is positive, caloric
testing is done by
physician.
CRANIAL NERVES 33

34. CN IX- GLOSSOPHARYNGEAL
NERVE
 ORIGIN-
◦ Medulla
 INNERVATION:
◦ Mucous membranes of
tonsils, pharynx, posterior
one-third of tongue,
pharyngeal muscles,
carotid sinus and carotid
body
 FUNCTION:
◦ Taste from posterior one-
third of tongue - Afferent
limb of gag, swallow, and
cardiac reflexes.
• DYSFUNCTION:
◦ Loss of taste; Neuralgia
CRANIAL NERVES
34

35. CN X – VAGUS NERVE ORIGIN-
◦ Medulla
 INNERVATION:
◦ Muscles of larynx, pharynx, and
soft palate.
◦ Parasympathetic innervation of
thoracic and abdominal viscera.
 FUNCTION:
◦ Muscles of larynx, pharynx, and
soft palate
◦ Sensation conveyed from the
heart, lungs, digestive tract,
carotid sinus, & carotid body
◦ Efferent limb of gag and swallow
reflex
• DYSFUNCTION:
• Loss of gag & swallow reflex
• Loss of carotid sinus
• oculocardiac reflex; Dysphagia
CRANIAL NERVES 35

36. CN IX- GLOSSOPHARYNGEAL
and CN X - VAGUS
 POSSITIVE FINDINGS-
 Evaluate voice quality
(hoarseness or dysarthria)
 Ask patient to open mouth,
say "ah", observe for
elevation of soft palate,
midline position of uvula.
 Gag reflex, bilaterally
 Swallowing
 Taste (bitter) posterior one-
third tongue
CRANIAL NERVES 36
CN IX and X considered jointly, actions are seldom compared separately; they
are always tested together.

37. CN IX- GLOSSOPHARYNGEAL
and CN X - VAGUS
 Negative Findings
 Loss of voice quality,
(dysarthria or hoarseness)
 Deviation of uvula toward
non-paralyzed side
 Swallowing difficulty or
nasal regurgitation
 Vagal irritation
(bradycardia)
CRANIAL NERVES 37

38. CN XI - SPINAL ACCESSORY
NERVE
 ORIGIN: Medulla
 INNERVATION:
Sternocleidomastoid &
trapezius muscles
 FUNCTION: Motor
function
Sternocleidomastoid &
trapezius
 DYSFUNCTION: Muscle
weakness.
CRANIAL NERVES 38

39. CN XI - SPINAL ACCESSORY
NERVE
• CLINICAL EVALUATION
• Palpate trapezius muscle as
patient shrugs shoulders
against resistance; evaluate
strength.
• Ask patient to turn head to
one side and push against
examiners hand or ask to flex
head against resistance,
palpate and evaluate strength
of sternocleidomastoid
muscle.
• Evaluate both right and left
side, compare for symmetry.
CRANIAL NERVES
39

40. CN XII –HYPOGLOSSAL
NERVE ORIGIN: Medulla
 INNERVATION: Muscles of the
tongue except palatoglossus
 FUNCTION: Movement of the
tongue
 DYSFUNCTION:
◦ Unilateral lesions can cause
paresis, atrophy, furrowing,
fibrillation and fasciculation on
the affected half
◦ On protrusion tongue deviates
towards the affected side due to
unopposed action of the
Contralateral GENIOGLOSSUS
 Flaccid paralysis
◦ Dysphagia
◦ Dysarthria
◦ Dyspnea
◦ Difficulty chewing food
CRANIAL NERVES
40

41. PUPILLARY REFLEX
 Afferent- Optic
 Efferent-
Oculomotor
 Yes(T)
 Yes(O)
 No(T)
 No(O)
 Yes(T)
 No(O)
 No(T)
 Yes(O)
CRANIAL NERVES 41
Normal
Testing side- A and E = +nt
Opposite side- E +nt
Probable lesion in A of eye
being checked
Probable lesion in E of
Opposite eye
Lesion of E on same side and
E of opposite eye is normal
 Afferent- Optic
 Efferent-
Oculomotor
 Yes(T)
 Yes(O)
 No(T)
 No(O)
 Yes(T)
 No(O)
 No(T)
 Yes(O)
Normal
Testing side- A and E = +nt
Opposite side- E +nt

42. CORNEAL REFLEX
CRANIAL NERVES 42
Normal
Testing side- A and E = +nt
Opposite side- E +nt
Probable lesion in A of eye
being checked
Probable lesion in E of
Opposite eye
Lesion of E on same side and
E of opposite eye is normal
 Afferent-Trigeminal
 Efferent- Facial
 Yes(T)
 Yes(O)
 No(T)
 No(O)
 Yes(T)
 No(O)
 No(T)
 Yes(O)
Normal
Testing side- A and E = +nt
Opposite side- E +nt