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Transcript
THE NEUROLOGICAL
EXAMINATION
Prof Mohammad Abduljabbar
Resources
• Neuroanatomy through Clinical Cases
by Hal Blumenfeld
• http://www.neuroexam.com/
• http://www.utoronto.ca/neuronotes/Neu
roExam/main.htm
• The Technique of the Neurologic
Examination by William DeMyer
• DeJong’s Neurologic Examination by
William W. Campbell
You must do a minimum basic
examination on every patient but you
don’t need to do every test
Tools of the trade
NEUROLOGICAL EXAM
• MENTAL STATUS
• CRANIAL NERVES
• MOTOR EXAM
– STRENGTH
– GAIT
– CEREBELLAR
• REFLEXES
• SENSATION
MENTAL STATUS
Level of Consciousness
• Awake and alert
• Agitated
• Lethargic
– Arousable with
• Voice
• Gentle stimulation
• Painful/vigorous stimulation
• Comatose
Mental Status Exam
•1. Level of alertness,attention and
cooperation
•We can test attention by seeing if the patient can remain focused on a
simple task, such as spelling a short word forward and backward (W-O-R-L-D
/ D-L-R-O-W is a standard), repeating a string of integers forward and
backward (digit span), or naming the months forward and then backward.
Normal digit span is 6 or more forward, and 4 or more backward, depending
slightly on age and education. Degree of cooperation should be noted,
especially if it is abnormal, since this will influence many aspects of the
exam.
LANGUAGE
•
•
•
•
•
•
FLUENCY
NAMING
REPETITION
READING
WRITING
COMPREHENSION
Aphasia vs. dysarthria
Mental Status Exam
•3. Speech and language
•Spontaneous speech: Note the patient's fluency, including phrase length, rate, and
abundance of spontaneous speech. Also note tonal modulation and whether paraphasic
errors (inappropriately substituted words or syllables), neologisms (nonexistent words), or
errors in grammar are present.
•Comprehension: Can the patient understand simple questions and commands?
Comprehension of grammatical structure should be tested as well
•Naming: Ask the patient to name some easy (pen, watch, tie, etc.) and some more
difficult (fingernail, belt buckle, stethoscope, etc.) objects
•Repetition: Can the patient repeat single words and sentences (a standard is "no ifs ands
or buts")?
•Reading: Ask the patient to read single words, a brief passage, and the front page of the
newspaper aloud and test for comprehension.
•Writing: Ask the patient to write their name and write a sentence.
MEMORY
• IMMEDIATE
– REALLY A MEASURE OF ATTENTION
RATHER THAN MEMORY
•
•
•
•
REMOTE
3 OBJECTS AT 0/3/5 MINUTES
HISTORICAL EVENTS
PERSONAL EVENTS
Mental Status Exam
•4. Memory for recent and remote events
•Recent memory: Ask the patient to recall three items or a brief story after a delay of 3 to
5 minutes. Be sure the information has been registered by asking the patient to repeat it
immediately before initiating the delay. Provide distracters during the delay to prevent the
patient from rehearsing the items repeatedly.
•Remote memory: Ask the patient about historical or verifiable personal events.
•Memory can be impaired on many different timescales. Impaired ability to register and
recall something within a few seconds after it was said is an abnormality that blends into
the category of impaired attention. If immediate recall is intact, then difficulty with recall
after about 1 to 5 minutes usually signifies damage to the limbic memory structures
located in the medial temporal lobes and medial diencephalon
ORIENTATION
• PERSON
– NOT WHO THEY ARE BUT WHO YOU
ARE
• PLACE
• TIME
OTHER COGNITIVE
FUNCTIONS
•
•
•
•
•
CALCULATION
ABSTRACTION
SIMILARITIES/DIFFERENCES
JUDGEMENT
PERSONALITY/BEHAVIOR
Mental Status Exam
•6. Apraxia
•The term apraxia will be used here to mean inability to follow a motor command that is
not due to a primary motor deficit or a language impairment. It is apparently caused by a
deficit in higher-order planning or conceptualization of the motor task. You can test for
apraxia by asking the patient to do complex tasks, using commands such as "Pretend to
comb your hair" or "Pretend to strike a match and blow it out" and so on. Patients with
apraxia perform awkward movements that only minimally resemble those requested,
despite having intact comprehension and an otherwise normal motor exam. This kind of
apraxia is sometimes called ideomotor apraxia. In some patients, rather than affecting the
distal extremities, apraxia can involve primarily the mouth and face, or movements of the
whole body, such as walking or turning around.
Mental Status Exam
•Folstein Mini-mental status exam
•This is a screening tool used to follow the cognitive decline
associated with dementia. It has been in wide use since 1975 and
takes 5-10 minutes to administer. It is a limited test instrument. This
examination is not suitable for making a diagnosis but can be used to
indicate the presence of cognitive impairment, such as when
dementia or head injury are suspected. People from different cultural
groups or low intelligence or education may score poorly on this
examination in the absence of cognitive impairment and well
educated people may score well despite having cognitive impairment
Mental Status Exam
•9. Sequencing tasks and frontal release signs
•Frontal lobe lesions in adults can cause the reemergence of certain primitive reflexes
that are normally present in infants. These so-called frontal release signs include the
grasp, snout, root, and suck reflexes. Of these reflexes, the grasp reflex is the most
useful in evaluating frontal lobe dysfunction.
•Patients with frontal lobe dysfunction may have particular difficulty in changing from
one action to the next when asked to perform a repeated sequence of actions.This
phenomenon is called perseveration
Mental Status Exam
•10. Delusions and Hallucinations
•Does the patient have any delusional thought processes? Does he have auditory or visual
hallucinations? Ask questions such as, "Do you ever hear things that other people don't
hear or see things that other people don't see?" "Do you feel that someone is watching you
or trying to hurt you?" "Do you have any special abilities or powers?"
•These abnormalities can be seen in toxic or metabolic abnormalities and other causes of
diffuse brain dysfunction, and in primary psychiatric disorders. In addition, abnormal
sensory phenomena can be caused by focal lesions or seizures in visual, somatosensory, or
auditory cortex, and thought disorders can be caused by lesions in the association cortex
and limbic system
Mental Status Exam
•11. Mood
•Signs of major depression include depressed mood, changes in eating and sleeping
patterns, loss of energy and initiative, low self-esteem, poor concentration, lack of
enjoyment of previously pleasurable activities, and self-destructive or suicidal thoughts
and behavior. Anxiety disorders are characterized by preoccupation with worrisome
thoughts. Mania causes patients to be abnormally active and cognitively disorganized.
CRANIAL NERVES
CRANIAL NERVE EXAM
• I - OLFACTORY
– DON’T USE A NOXIOUS STIMULUS
– COFFEE, LEMON EXTRACT
• II - OPTIC
– VISUAL ACUITY
– VISUAL FIELDS
– FUNDOSCOPIC EXAM
Cranial Nerve1
Olfaction
• Not tested much unless a frontal lobe
tumor is suspected
• May be damaged in patients with closed
head injuries,nasal obstruction,viral
infections, and can be abnormal in
Parkinsons disease, Alzheimer’s,and
Multiple Sclerosis
• Test by asking if patients can
smell,coffee,vanilla, or cinnamon in each
nostril. Avoid http://www.neuroexam.com/
noxious odors ( ie NH3)
http://www.braininjury.com/images/cranialnerveinjury.jpg
http://commons.wikimedia.org/wiki/Image:Head_olfactory_ne
rve.jpg
Cranial Nerve 2
Optic Nerve
•Visual Acuity (test with hand card)
•Color Vision (loss of color vision especially
red is an important symptom of optic neuritis)
•Visual Fields (can be tested at the bedside
by counting fingers in each quadrant)
•Visual Extinction (to detect visual neglect)
•Funduscopic Examination
Cranial Nerve 2 and 3
Pupillary responses
•The size and shape of the pupil should be recorded at rest. Under normal conditions, the pupil
constricts in response to light. Note the direct response, meaning constriction of the illuminated pupil,
as well as the consensual response, meaning constriction of the opposite pupil.
•Test the pupillary response to accommodation. Normally, the pupils constrict while fixating on an
object being moved from far away to near the eyes.
•Direct response (pupil illuminated). The direct response is impaired in lesions of the ipsilateral optic
nerve, the pretectal area, the ipsilateral parasympathetics traveling in CN III, or the pupillary constrictor
muscle of the iris.
•Consensual response (contralateral pupil illuminated). The consensual response is impaired in lesions
of the contralateral optic nerve, the pretectal area, the ipsilateral parasympathetics traveling in CN III,
or the pupillary constrictor muscle.
•Accommodation (response to looking at something moving toward the eye). Accommodation is
impaired in lesions of the ipsilateral optic nerve, the ipsilateral parasympathetics traveling in CN III, or
the pupillary constrictor muscle, or in bilateral lesions of the pathways from the optic tracts to the
visual cortex. Accommodation is spared in lesions of the pretectal area.
Pupillary Size is determined by the light input,
sympathetic and parasympathetic tone
Text
CRANIAL NERVE EXAM
• III/IV/VI OCULMOTOR,
TROCHLEAR, ABDUCENS
– PUPILLARY RESPONSE
– EYE MOVEMENTS
– OBSERVE LIDS FOR PTOSIS
• V - TRIGEMINAL
– MOTOR - JAW STRENGTH
– SENS - ALL 3 DIVISIONS
Cranial Nerve 3,4,6
Extraocular Movements
•Observe the eyes at rest to see if there are any abnormalities such as spontaneous
nystagmus (see below)or dysconjugate gaze (eyes not both fixated on the same point)
resulting in diplopia (double vision)
•Test smooth pursuit by having the patient follow an object moved across their full range
of horizontal and vertical eye movements. Test convergence movements by having the
patient fixate on an object as it is moved slowly towards a point right between the
patient's eyes
•In comatose or severely lethargic patients, the vestibulo-ocular reflex can be used to test
whether brainstem eye movement pathways are intact. The oculocephalic reflex, a form
of the vestibulo-ocular reflex, is tested by holding the eyes open and rotating the head
from side to side or up and down
Cranial Nerve 5
Facial Sensation and Muscles of Mastication
•Test facial sensation using a cotton wisp and a sharp object. Also test for
tactile extinction using double simultaneous stimulation.
•The corneal reflex, which involves both CN 5 and CN 7, is tested by
touching each cornea gently with a cotton wisp and observing any
asymmetries in the blink response.
•Feel the masseter muscles during jaw clench. Test for a jaw jerk reflex by
gently tapping on the jaw with the mouth slightly open.
CRANIAL NERVES
• VII - FACIAL
– OBSERVE FOR FACIAL ASYMMETRY
– FOREHEAD WRINKLING, EYELID
CLOSURE, WHISTLE/PUCKER
• VIII - VESTIBULAR
– ACUITY
– RINNE, WEBER
Cranial Nerve 7
Muscles of Facial Expression and
Taste
•Look for asymmetry in facial shape or in depth of furrows such as the nasolabial fold. Also
look for asymmetries in spontaneous facial expressions and blinking. Ask patient to smile,
puff out their cheeks, clench their eyes tight, wrinkle their brow, and so on. Old
photographs of the patient can often aid your recognition of subtle changes
•Check taste with sugar, salt, or lemon juice on cotton swabs applied to the lateral aspect
of each side of the tongue. Like olfaction, taste is often tested only when specific
pathology is suspected, such as in lesions of the facial nerve, or in lesions of the gustatory
nucleus
•The upper motor neurons for the upper face project to the facial nuclei bilaterally.
Therefore, upper motor neuron lesions, such as a stroke, cause contralateral face
weakness sparing the forehead, while lower motor neuron lesions, such as a facial nerve
injury, typically cause weakness involving the whole ipsilateral face.
Cranial Nerve 8
Hearing and Balance
•Test to see can the patient hear fingers rubbed together or words whispered just
outside of the auditory canal and identify which ear hears the sound? A tuning fork can
be used to perform the Weber and Rinne test to evaluate sensorineural and conductive
hearing loss respectively
•Hearing loss can be caused by lesions in the acoustic and mechanical elements of the
ear, the neural elements of the cochlea, or the acoustic nerve (CN VIII). After the
hearing pathways enter the brainstem, they cross over at multiple levels and ascend
bilaterally to the thalamus and auditory cortex. Therefore, clinically significant unilateral
hearing loss is invariably caused by peripheral neural or mechanical lesions.
•Vestibular testing is not done routinely.
CRANIAL NERVES
• IX/X - GLOSSOPHARYNGEAL,
VAGUS
– GAG
• XI - SPINAL ACCESSORY
– STERNOCLEIDOMASTOID M.
– TRAPEZIUS MUSCLE
• XII - HYPOGLOSSAL
– TONGUE STRENGTH
– RIGHT XII THRUSTS TONGUE TO LEFT
Cranial Nerve 9 and 10
Palatal Elevation and Gag Reflex
•Does the palate elevate symmetrically when the patient says, "Aah"? Does the patient
gag when the posterior pharynx is brushed? The gag reflex needs to be tested only in
patients with suspected brainstem pathology, impaired consciousness, or impaired
swallowing.
•Palate elevation and the gag reflex are impaired in lesions involving CN 9, CN 10, the
neuromuscular junction, or the pharyngeal muscles.
Cranial Nerve11
Sternocleidomastoid and Trapezius
Muscles
•Ask the patient to shrug their shoulders, turn their head in both directions, and raise
their head from the bed, flexing forward against the force of your hands.
•Weakness in the sternocleidomastoid or trapezius muscles can be caused by lesions in
the muscles, neuromuscular junction, or lower motor neurons of the accessory spinal
nerve (CN XI). Unilateral upper motor neuron lesions in the cortex or descending
pathways cause contralateral weakness of the trapezius, with relative sparing of
sternocleidomastoid strength
Cranial Nerve12
•Note any atrophy or fasciculations (spontaneous quivering movements caused by firing
of muscle motor units) of the tongue while it is resting on the floor of the mouth. Ask
the patient to stick their tongue straight out and note whether it curves to one side or
the other. Ask the patient to move their tongue from side to side and push it forcefully
against the inside of each cheek
•Fasciculations and atrophy are signs of lower motor neuron lesions. Unilateral tongue
weakness causes the tongue to deviate toward the weak side. Tongue weakness can
result from lesions of the tongue muscles, the neuromuscular junction, the lower motor
neurons of the hypoglossal nerve (CN XII), or the upper motor neurons originating in
the motor cortex. Lesions of the motor cortex cause contralateral tongue weakness.
Hypoglossal Nerve Injury
MOTOR EXAMINATION
Motor Examination
Motor Examination
•Observe: Look for any twitches, tremors, abnormal movements or
postures. Look carefully for hypokinesia,decreased eye blinking or staring
which could be indicative or an extrapyramidal disorder such as Parkinson’s
disease
•In suspected lower motor neuron disorders,look for muscle wasting or
fasiculations
•Palpate muscles in cases of suspected myopathy to check for muscle
tenderness
•Passively move each limb to check muscle tone. Ask the patient to relax
before beginning
MUSCLE OBSERVATION
• ATROPHY
• FASCIULATIONS
ABNORMAL MOVEMENTS
• TREMOR
– REST
– WITH ARMS OUTSTRETCHED
– INTENTION
• CHOREA
• ATHETOSIS
• ABNORMAL POSTURES
TONE
• INCREASED, DECREASED, NORMAL
• COGWHEELING
• CLASP KNIFE
Motor Examination
•Test for subtle weakness first by checking
pronator drift, finger tapping, pronation/supination
movements and toe tapping.
•Then check individual muscles for strength using
the MRC scale to rate strength
STRENGTH
• STRENGTH
–
–
–
–
GRADED 0 - 5
0 - NO MOVEMENT
1 - FLICKER
2 - MOVEMENT WITH GRAVITY
REMOVED
– 3 - MOVEMENT AGAINST GRAVITY
– 4 - MOVEMENT AGAINST RESISTANCE
– 5 - NORMAL STRENGTH
STRENGTH EXAM
• UPPER AND LOWER EXTREMITIES
• DISTAL AND PROXIMAL MUSCLES
• GRIP STRENGTH IS A POOR
SCREENING TOOL FOR STRENGTH
• SUBTLE WEAKNESS
– TOE WALK, HEEL WALK
– OUT OF CHAIR
– DEEP KNEE BEND
REFLEXES
MUSCLE STRETCH
REFLEXES (DEEP TENDON
REFLEXES)
• GRADED 0 - 5
–
–
–
–
–
–
0 - ABSENT
1 - PRESENT WITH REINFORCEMENT
2 - NORMAL
3 - ENHANCED
4 - UNSUSTAINED CLONUS
5 - SUSTAINED CLONUS
MSR / DTR
•
•
•
•
•
BICEPS
BRACHIORADIALIS
TRICEPS
KNEE
ANKLE
OTHER REFLEXES
• Upper motor neuron dysfunction
– BABINSKI
• present or absent
• toes downgoing/ flexor plantar response
– HOFMAN’S
– JAW JERK
• Frontal release signs
–
–
–
–
GRASP
SNOUT
SUCK
PALMOMENTAL
Plantar Response
•Test the plantar response by scraping an object across the sole of the
foot beginning from the heel, moving forward toward the small toe, and
then arcing medially toward the big toe. The normal response is
downward contraction of the toes. The abnormal response, called
Babinski's sign, is characterized by an upgoing big toe and fanning
outward of the other toes.The presence of Babinski's sign is always
abnormal in adults, but it is often present in infants, up to the age of
about 1 year.
CEREBELLAR FUNCTION
• RAPID ALTERNATING MOVEMENTS
• FINGER TO FINGER TO NOSE
TESTING
• HEEL TO SHIN
• GAIT
– TANDEM
Coordination
•Normal performance of these motor tasks depends on the integrated
functioning of multiple sensory and motor subsystems. These include
position sense pathways, lower motor neurons, upper motor neurons, the
basal ganglia, and the cerebellum. Thus, in order to convincingly
demonstrate that abnormalities are due to a cerebellar lesion, one must
first test for normal joint position sense, strength, and reflexes and confirm
the absence of involuntary movements caused by basal ganglia lesions. As
already mentioned, limb ataxia is usually caused by lesions of the cerebellar
hemispheres and associated pathways, while truncal ataxia is often caused
by damage to the midline cerebellar vermis and associated pathway
•Tests for Limb Ataxia include: Rapid alternating movements, Finger Nose
Finger test, and Heel Knee Shin test
Gait evaluation
• Include walking and turning
• Examples of abnormal gait
–
–
–
–
–
High steppage
Waddling
Hemiparetic
Shuffling
Turns en bloc
Gait
•Gait involves multiple sensory and motor systems. These include vision,
proprioception, lower motor neurons, upper motor neurons, basal ganglia, the
cerebellum, and higher-order motor planning systems in the association cortex
•Observe:
•Stance, how far apart are the feet, posture, stability, how high the feet are raised off
the floor, trajectory of leg swing and whether there is circumduction (an arced
trajectory in the medial to lateral direction), leg stiffness and degree of knee bending,
arm swing, tendency to fall or swerve in any particular direction, rate and speed,
difficulty initiating or stopping gait, and any involuntary movements that are brought
out by walking. Turns should also be observed closely. The patient's ability to rise
from a chair with or without assistance should also be recorded.
•To bring out abnormalities in gait and balance, ask the patient to do more difficult
maneuvers : ie Tandem Gait
Romberg Sign
• Stand with feet together - assure patient
stable - have them close eyes
• Romberg is positive if they do worse with
eyes closed
• Measures
– Cerebellar function
– Frequently poor balance with eyes open and
closed
– Proprioception
– Frequently do worse with eyes closed
– Vestibular system
SENSORY EXAM
Sensory Exam
•The sensory exam relies to a large extent on the ability or
willingness of the patient to report what he is feeling. It can
therefore often be the most difficult and unreliable part of the
neurologic exam
Primary Sensation
•Light Touch
•Pinprick
•Vibration
•Joint Position
•Temperature
•Two point discrimination
•The pattern of sensory loss can provide important information that helps localize
lesions to particular nerves, nerve roots, and regions of the spinal cord, brainstem,
thalamus, or cortex
SENSORY EXAM
• VIBRATION
– 128 hz tuning fork
• JOINT POSITION SENSE
• PIN PRICK
• TEMPERATURE
Start distally and move proximally
HIGHER CORTICAL
SENSATIONS
• GRAPHESTHESIA
• STEREOGNOSIS
• DOUBLE SIMULTANEOUS
STIMULATION
• BAROSTHESIA
• TEXTURES
Cortical sensation
•Graphesthesia
•Sterognosis
•Double Simultaneous Stimulation
•Intact primary sensation with deficits in cortical sensation such as agraphesthesia or
astereognosis suggests a lesion in the contralateral sensory cortex. Note, however, that
severe cortical lesions can cause deficits in primary sensation as well. Extinction with
intact primary sensation is a form of hemineglect that is most commonly associated with
lesions of the right parietal lobe. Extinction can also be seen in right frontal or
subcortical lesions, or sometimes in left hemisphere lesions causing mild right
hemineglect