Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Neuroanaesthesia PPT 9 Cns Neurological Examination Part 1 Lecture Notes
NEUROLOGICAL EXAMINATION
Components of a CNS EXAMINATION
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Higher mental functions
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Cranial Nerves
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Motor system examination ? bulk, tone, power
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Reflexes.
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Coordination ? fine movements, balance and gait.
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Sensory system examination.
Higher mental functions
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The mental status examination is a structured assessment of the patient's behavioural and
cognitive functioning.
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The specific cognitive functions of alertness, language, memory, constructional ability, and
abstract reasoning are the most clinically relevant.
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It should be a requisite part of standard neurologic examination ? at least Mini Mental State
Examination should be performed in neurologic patients.
Appearance and General Behavior
These variables give the examiner an overall impression of the patient.
The patient's physical appearance (apparent vs. stated age), grooming
(immaculate/unkempt), dress (subdued/riotous), posture (erect/kyphotic), and
eye contact (direct/furtive) are all pertinent observations aiding the diagnosis.
Certain specific syndromes such as unilateral spatial neglect and the
disinhibited behavior of the frontal lobe syndrome are readily appreciated
through observation of behaviour alone.
Structured Examination of Cognitive Abilities
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Performing a mini-mental status examination.
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Or a using a Mental status questionnaire.
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These measures only give a snapshot of patients cognition.
Mini mental state examination
MMSE is a 30 point scoring system and is one of the most widely used brief
screening systems for cognitive state.
Components include: I. Orientation
ii. Registration
iii. Attention and Calculation
iv.Recall
V. Language
1.Orientation ( total 10 points )
What is the orientation to time? time ( 1 point) date ( 1 point)
day ( 1 point) Month ( 1 point) year( 1 point) ?
A total of 5 points.
What is the name of this: (orientation to place) Ward ( 1 point)
hospital ( 1 point) district ( 1 point) town ( 1 point) country ( 1 point)
A total of 5 points.
2. Registration ( 3POINTS )
Name any three objects
Score 1, 2, 3 points according to how many the patient repeats.
Re-submit the list until the patient is word perfect in order to use this for a
later test of recall
Score only for first attempt 3 points
3. Attention and calculation
Have the patient subtract 7 from 100 and then from
the result a total of five times.
Score 1 point for each correct subtraction 5 points
4.Recall ( 3points)
Ask for three objects used in the registration test.
one point being awarded for each correct answer.
A total of 3 points avoided per correct recall.
5.Language and Intelligence (9points)
1 point each for two objects correctly named (pencil and watch) 2 points.
1 point for correct repetition (No ifs and buts) 1 point.
3 points if three-stage commands correctly obeyed
`Take this piece of paper in your right hand, fold it in half, and
place it on the floor'. 3 points.
1 point for correct response to a written command such as `close your eyes'.
1 point.
Have the patient write a sentence. Award 1 point if the sentence is
meaningful, has a verb and a subject. 1 point
Test the patient's ability to copy a complex diagram of two intersected
pentagons. 1 point
Total score is 30. Maximum score of 30 is normal.
Scores between 15 and 22 suggest mild to moderate dementia.
Scores lower than 21 are associated with severe cognitive impairment
CRANIAL NERVE EXAMINATION
12 pairs of cranial nerves:
CN1 Olfactory
CN2 Optic
CN3 Oculomotor
CN4 Trochlear
CN5 Trigeminal
CN6 Abducens
CN7 Facial
CN8 Vestibulocochlear
CN9 Glossopharyngeal
CN10 Vagus
CN11 Spinal Accessory nerve
CN12 Hypoglossal
On broad inspection
Look for facial asymmetry
Look for ocular deviation , Ptosis or
Unequal pupils ( Anisocoria )
CN1 ? Olfactory nerve
SENSORY ONLY cranial nerve
Smell sensation
to test olfactory function, the patient should be asked to distinguish between smells
such as coffee and cinnamon or other mild spices.
Noxious stimulation (such as smelling ammonium salts) that irritate the nasal mucosa
should be avoided.
Test each nostril separately with familiar smells (e.g. coffee)
CN2 ? Optic nerve examination
SENSORY only cranial nerve.
Visual acuity
Visual fields
Reflexes:
Pupillary light reflex
Accommodation reflex
Colour vision
Fundoscopy
Visual Acuity- Snellen's chart at 6 metres. (bring
them closer if they cannot read top letter)
One eye tested at a time
With normal correction establish the smallest
line patient can read
If acuity too poor for Snellen chart, try:
Finger counting at 20cm
Hand movement
Perception of light
Visual fields:
Ask patient to look at your eye
Test one eye at a time
Cover your eye that is opposite the
patient's covered eye
Ask patient to report finger
movements on both sides, move
inwards until they are able to see them
Compare with your own visual field
Ocular reflexes
Pupillary light reflex
Ask patient to fixate on a distant point
Shine light into one eye
Look for constriction of that pupil (direct
reflex) and the other pupil (consensual
reflex)
Swinging light test
Swing light between the eyes
If optic nerve intact, both stay
constricted
If optic nerve damaged, pupils
appear to dilate when light shone
directly into it
Relative afferent pupillary defect
Accommodation reflex
Ask patient to fixate on distant object
Present an object around 6 inches
from their face and ask them to focus
on it
Look for pupil constriction
Colour vision
Ishihara plates ? ask patient to read
out the numbers
Not always available (available as an
iPhone app!)
Fundoscopy
This involves looking into the back of
the patient's eye with an
ophthalmoscope to visualise the
retina and optic disc.
CN3 (OCULOMOTOR)
CN4 (TROCHLEAR)
CN6 (ABDUCENS)
MOTOR ONLY cranial nerves.
Eye movements:
CN3 ? Superior rectus, Inferior rectus,
Medial Oblique, Inferior oblique
CN4 ? Superior Oblique
CN6 ? Lateral Rectus
On inspection:
Eye moves towards the muscles that still work
Third nerve palsy:
Down and outward deviation
= Tramps Pupil
Fourth nerve palsy:
Subtle ? Head tilted away from lesion
Sixth nerve palsy:
Inward deviation
Inability to look out
Ocular movements
Ask patient to keep their head still and follow
your finger with their eyes
Ask patient to report any double vision in
neutral position or during test
Move your finger slowly through a large double
letter HH
Observe for full eye movements
CN5 ? Trigeminal nerve
SENSORY & MOTOR (mixed) cranial nerve
Sensory ? 3 divisions:
Ophthalmic
Maxillary
Mandibular
Motor:
Muscles of mastication:
Jaw jerk reflex
Sensory testing
Test light touch sensation in each of the areas
shown
Demonstrate on sternum for reference.
Ask patient to close their eyes and report when
they feel it and if it feels normal
Corneal reflex ? touch cornea lightly with cotton
wool and look for blink in both eyes
Motor testing
Muscles of mastication:
Inspect for wasting
Palpate on jaw clenching
Resisted mouth opening
Jaw jerk reflex
Mouth slightly open, jaw relaxed
Place finger on chin and tap with tendon hammer
Normally absent or small
Brisk in UMN lesions
CN7 ? Facial nerve
SENSORY & MOTOR cranial nerve.
Sensory
Taste sensation to anterior 2/3 of
tongue
Motor
Muscles of facial expression
Sensory:
Not routinely tested
Motor
Muscles of facial expression ? ask patient
to:
Raise eyebrows
Close their eyes and don't let you open
them
Smile
Puff out their cheeks
CN8 ? Vestibulocochlear nerve
SENSORY only cranial nerve.
Carries hearing and balance input from ear
Crudely test hearing
Whisper a number into each ear whilst making a
distracting sound in the other ear
Ask patient to repeat the number
If concerned, perform Weber's and Rinne's tests
Weber's test:
? Tuning fork in centre of forehead ? in
which ear does it sound louder?
? Normally equal in both ears.
? Conductive hearing loss:
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Lateralises to affected side
? Sensorineural hearing loss:
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Lateralises to non-affected side
Rinne's test
? Tuning fork on Mastoid
? When sound stops move next to ear
? Ask if can now hear it?
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Yes = Normal
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or Equally affected = Sensorineural
Deafness
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No = Conductive deficit
CN9 & 10 ? GLOSSOPHARYNGEAL & VAGUS NERVE
SENSORY & MOTOR
CN9 Sensory
Nasopharynx
Posterior 1/3 Tongue
Middle + Inner Ear
CN10 Sensory
Pharynx + Larynx
CN10 Motor
Pharynx + Larynx
Palate
Observe for any dysphonia
Ask patient to open mouth wide and say "aah"
Observe for any deviation of the uvula
Deviation would be AWAY from the side of the
lesion
Gag reflex Not routinely done
CN11 ? Spinal accessory nerve
MOTOR only cranial nerve
Trapezius muscle
Sternocleidomastoid muscle
Trapezius muscle
Ask patient to shrug their shoulders
against resistance
Sternocleidomastoid muscle
Ask patient to turn their head to each
side against resistance
CN 12 ? Hypoglossal Nerve
MOTOR only
Muscles of the tongue
Muscles of the tongue : Observe for
fasciculations
Ask patient to stick out their tongue
Observe for deviation
Deviation would be TOWARDS the side of the
lesion
Check power of muscles by asking patient to
push their tongue into the side of their cheek
and pressing on it from the outside
Videos uploaded after sorting permission from "The University of Utah "
neurology center.
This post was last modified on 07 April 2022