CNS exam Flashcards
Scope of the system
Narrow the picture as much as possible using a good history. Look to answer these questions:
Local or diffuse?
How has it developed over time?
Restricted to nervous system or include other systems?
CNS, PNS or Both?
Goal: Integrate History and PE
Get to WHERE the lesion is
Then you can develop a meaningful “WHAT the lesion is” differential. Don’t jump too fast
CNS scope
Cortex Basal Ganglion Brain Stem Cerebellum Spinal Cord
PNS scope
Cranial Nerves Sensory Afferents Motor Efferents Neuromuscular Junction Muscle itself
Anxiety and depression
estimated to be 30% of primary care visits.
Unexplained persistent symptoms frequent:
Headache, GI issues, insomnia, fatigue, chronic pain
Mental Status Exam
1. Appearance and Behavior level of consciousness posture, motor behavior, hygiene 2. Mood/Affect 3. Speech/Language articulation, relevance, word finding, rate, fluency 4. Thoughts/Perceptions logic, coherence, content, insight, judgment 5. Cognitive/Executive Function orientation, memory, abstract thinking, performance
- Appearance and Behavior
Level of Consciousness: State of awareness of self and environment. Impaired by disease of the brainstem reticular activating system, or damage in parts of BOTH hemispheres
ALERT: Awake, not sleepy or tired, responding appropriately to the environment
LETHARGIC (sleepy): awake, but tending to fall asleep if not gently stimulated
STUPOROUS: falling asleep unless vigorously stimulated
COMATOSE: a sleep-like state from which the patient cannot be awakened
Posture and Motor Activity:
Calm? Constant motion?
Depression with anxiety?
Side effect to neuroleptic medication?
thyroid medication?
Hygiene
You think it is fine, They think they smell.
Delusion?
. Affect/Mood
Observe expressions and affect
Appropriate for situation? Engaged? Angry? Anxious? Indifferent? Detached?
Depression Drugs Fatigue ETOH Insomnia Meds Concentration Steroids Endocrine
Anxiety: Palpitations Breathless Tremors Numbness Dry mouth ETOH withdrawl? Hyperthyroid?
Fear
Paranoia?
Complex Partial Seizure?
Completely appropriate?
Language
The clinical exam of language should include assessment of: Spontaneous Speech Naming Comprehension Repetition Reading Writing
You are evaluating for Aphasia: Disorder in producing or understanding language.
Spontaneous Speech: Look for
Articulation Appropriate word finding. Assess for Paraphasia = Substituting similar sounding syllables or words; Paraphasic errors. “pen” for “pencil” “plentil” for “pencil” Is there normal prosody: the melody or variable tone of speech?
Spontaneous Speech:
Verbal Fluency: do they maintain appropriate rate, flow, volume, content, meaning and melody (prosody)?
If your patient lacks meaning or fluency, evaluate for Aphasia: Disorder in understanding or producing language: spoken or written
Testing for Aphasia:
Naming: test the ability to name objects
ANOMIA: loss of the ability to name common objects; the most common deficit in true aphasia
Comprehension: follow commands.
“Point to nose” Point to nose then knee”
Repetition: have the patient repeat some simple words or a phrase
“No if’s, and’s or but’s”
Reading and Writing: short exercises
Aphasia
Disorder in understanding or producing language: spoken or written
Injury, Disease, Psychogenic
Dysphasia
Impairment in use of speech that is clear “Dys-phasia”
Failure to arrange properly in sentence
Dysarthria
Imperfect articulation due to lack of motor coordination; damaging event CNS or PNS. Language comprehension and use may be fine.
More stuff on aphasia
Aphasia is due to a localized lesion of the dominant hemisphere of the brain:
The left cerebral hemisphere in 99% of all right-handed patients and probably 70% of left-handed patients
Most ambidextrous patients are also left hemisphere dominant
Aphasia may be the only sign of a new neurological disease, such as stroke, tumor or head trauma, or recent seizure
Wernicke’s area
transforms sensory input into neural word representations to give a word meaning.
Broca’s area
transforms these neural word representations into actual articulations that can be spoken.
Aphasia
Loss of power of expression or the comprehension of spoken or written language
Damage to Broca’s or Wernicke’s or their interconnection causes aphasia
the language of broca’s vs wernicke’s aphasia
Brocas Aphasia click to see video
“Expressive” Aphasia
understanding of spoken language mostly preserved
Wernicke’s Aphasia click to see video
“Receptive” Aphasia
fluent speech that makes no sense
Thoughts and Perception
Brocas Aphasia click to see video
“Expressive” Aphasia
understanding of spoken language mostly preserved
Wernicke’s Aphasia click to see video
“Receptive” Aphasia
fluent speech that makes no sense
Cognitive Function
Orientation: Person, Place, Time
Attention: Ability to concentrate
Memory: Recent and Remote
Executive Function
Abstract Thinking/Insight
Calculation
Constructional Ability
Orientation
PERSON (name): seldom lost unless the patient has aphasia or schizophrenia
- PLACE (location): often lost in some hospitalized patients, or delirious/extremely demented outpatients
- TIME: most commonly lost of these three; include time of day, day of week, month, year if possible
Typically, physicians write “A&O x 3”
Memory
RECENT Memory: the ability to store new information, up to a few days
REMOTE Memory: more distant memories. Includes autobiographical (dates of graduation, marriage, etc.) or historical (date of wars, elections, sports, etc.)
Can be the only sign or symptom of a brain disease
Alzheimer’s dementia almost always begins as a progressive loss of memory; first recent, and then distant memory
Recent Memory
Testing recent memory: “Please listen to these 3 words, and then repeat them. I will ask you to remember them soon.” Ask them in approximately 3-5 minutes.
Occasionally a normal patient will recall only 2/3, but recalling 0, or 1 words on two attempts is pathologic
Also tested by:
1. “How long have you been in the hospital?” 2. Giving a patient a brief story to remember, perhaps three or four sentences long 3. “What did you have for breakfast (or lunch, dinner)?”
Remote Memory
Less often tested, mostly for confirming a diagnosis of dementia
Examples:
1. When did you graduate from high school? 2. When did you get married? 3. How many children do you have? 4. When did you retire? 5. When did the Vietnam War (or World War II) occur? 6. Can you name some recent presidents?
Executive Function: Insight
Insight/Judgment, Reasoning Ability, Abstract thinking
It tests the “higher abilities” that patients should possess, or had before they became ill
Tests mostly for dementia, or any disease of the FRONTAL lobes and their connections
Crucial in diagnosing Alzheimer’s Disease and the other common causes of dementia.
Proverbs
1. “Look before you leap” 2. “People in glass houses shouldn’t throw stones” 3. “Still waters run deep”
Situational questions for choice “What would you DO if you:
1. Found a closed envelope fully-addressed and stamped ? 2. Found a wallet on the street?
Similarities can be tested; How are the following alike (or different)?
1. Apples and oranges 2. Tables and chairs 3. Californians and Texans 4. Shirts and dresses
Delirium
acute confusion episode, may be due to infection, uremia, alcohol withdrawal. Disoriented, poor judgment, delusions common, attention poor, mood fluctuates
“Everything’s an Emergency!”
Dementia:
insidious, slowly progressive, affect often flat, maintains orientation and attention until late in process. Altzheimer’s, B12 deficiency, hypothyroid, head trauma. Can have acute angry, delusional episodes later in the course of disease.
What’s the best way to distinguish agitated dementia from delirium?
Attention testing typically the best exam to distinguish agitated dementia from delirium . Poor attention think delirium
____ is often disturbed, but ___ is seldom disturbed
Language is often disturbed, but speech is seldom disturbed
Executive Function: Calculation
Number span: normal patients should be able to repeat 5 or 6 numbers in correct order, or do 4 numbers in reverse order
- Spelling a common word, backwards and forwards, ‘WORLD’
- Do the months of the year or the days of the week, forwards and backwards
- Doubling a number; 9X9=81, 162, 324
Executive Function: Constructional Ability
Constructional Ability: copy a figure or ask them to draw something simple
Integration of Motor Activity: ask to perform a task, see if they can. Apraxia is the inability to perform the command. Can also be tested here.
Mini Mental Status Exam:
Screening tool for mental status
23-30= normal 19-23= borderline
Mental Status Screening
Recent study found elderly well still able to visit their doctor alone for a routine PE rated their cognition equally good as those with known dementia. Yikes.
Use cognitive screening tests like MMSE or Folstein
Refer to Neurophychologist for full evaluation, diagnosis and treatment options depression, dementia, concussion/TBI detect malingering determine competence cognitive rehabilitation (TBI) behavioral therapy (chronic pain
cerebellum
The cerebellum receives sensory and motor input to coordinate motor activity, maintain equilibrium and control posture.
cerebellar testing
Gait Regular walk Tandem: one foot in front of the other Heel/toe: away on heels, back on toes Heel to Knee and slide down shin (heel to shin) Bilateral smoothness, accuracy Repeat eyes closed for higher sensitivity Romberg/Pronator Drift: tested together
tracts and the cerebellar testing
Posterior column = motor efferents
Contralateral lesion in corticospinal tract because it decussates as it leaves the medulla; this tract is most responsible for motor signals to the hands, particularly fine movement. So drift in the right arm is a bad signal originating in the left corticospinal tract before it decussates.
Tandem is one foot directly in front of the other, can go forward then backwards. Be there to catch them if needed
Heel/Toe is walking forward on heels, then turning around and walking forward on toes. The order is not important
Romberg
tests ataxia specific to posterior column function. While positioned and eyes open, balance is maintained. Closing eyes removes visual input and ataxia (falling over) occurs. Direction of the fall may indicate where the lesion is.
Pronator drift:
in same stance as for Romberg, if the arm drifts downward (and occasionally lateral) when eyes are closed it is specific for a contralateral corticospinal tract lesion/disease
Cerebellar ataxia is present with eyes open or closed, ie, not a function of proprioceptive input.
Fingers to nose cerebellar testing
Finger-to-Nose Eyes Open (“your nose, my finger”)
Make sure the patient extends his arm “completely” to reach your own index finger, this enhances any
abnormality if present.
Move finger up, down and
cross midline
Clumsy, vary in speed/force, past point
= Dysmetria
Finger to Nose Eyes Closed (drunk test)
Standing, eyes closed, arms stretched
out to side, bring each in to nose.
Poor coordination worsens with eyes
closed.
voice dysmetria
Voice Dysmetria:
Count to 10 as quickly as possible.
Motor coordination
dysdiadochokinesis and cerebellar testing
Rapid Alternating Movements
Flip hand over in other palm
rapid; must lift hand off palm
Can also use the thigh
DYSDIADOCHOKINESIS: one movement cannot be abruptly stopped and followed by the opposite movement: slow, irregular and clumsy
what does the cranial nerve exam do?
Localizes pathologic processes specific to individual cranial nerves and can indicate where pathology is involved. This assists in diagnostic accuracy of neurologic disorders.
Olfactory nerve
Olfactory is seldom tested, unless the patient complains of a loss of smell, or there is a frontal injury or possible frontal lobe tumor
Usually tested only for presence/absence, with some coffee beans, or cinnamon
Abnormalities seen with concussion(mild traumatic brain injury or TBI)
Typically, physicians will write, “Cranial nerves 2 through 12 intact.” CN 2-12 intact
But be sure to DO IT if you document this
Optic nerve
Acuity
Pupillary Reflex: Afferent is CN II, it senses the light. Efferent: CN III (Oculomotor) Visual field exam
Ophthalmoscopic examination is direct
visualization of retina including optic disc and vessels. Optic nerve exam is primarily functional
CN III, IV, VI
Look at eyes in the primary position:
esotropia (medial deviation)
exotropia (lateral deviation)
Efferent pupillary response to light
(III Oculomotor: levator palpebrae, sup/inf rectus, inf oblique, medial rectus)
Extraocular movements: Six cardinal directions
Trochlear (IV Superior Oblique) moves the eye downward and out.
Abducens (VI Lateral Rectus) move laterally
Remember the cover/uncover test to check bilateral central focus; looking for strabismus
CN VI palsy
Mild or total loss of lateral rectus function = horizontal diplopia
Often without a localizing sign; INCREASED INTRACRANIAL PRESSURE ANYWHERE may cause a unilateral or bilateral CN VI palsy
CN V: The Trigeminal Nerve
Sensory: for the face, 3 divisions
Test sensation to each bilaterally: soft or temperature, and/or pinpick
Motor: masseter and pterygoid: clench teeth, move jaw side to side
Corneal Reflex: Gently touch lateral cornea w/ cotton or gauze
Afferent: CN V senses the stimulus
Efferent: CN VII motor to blink
Both eyes should blink together
There is sensory innervation from the cervical root in these same distributions.
To localize Trigeminal distribution test across midline in these areas ONLY.
CN VII: The Facial Nerve
Muscles of facial expression
Upper face: closing the eyes, raising the eyebrows
Lower face: smiling
Taste of anterior 2/3 tongue
Lacrimation
Salivation
Stapedius muscle of middle ear (dampens sound)
CN VII can be affected either centrally or peripherally.
Central:
Cortex or brainstem
Muscles of lower face only
Peripheral: muscles of unilateral, same side upper and lower face
Facial nerve central lesions
- Cerebral hemisphere lesion: signal must cross before it is manifested
Lower facial weakness of the opposite side.
Extremities on opposite side - Brainstem lesion:
Lower facial weakness of the same side.
facial nerve peripheral lesions
Peripheral Lesion: After leaving the brainstem
Commonly compressed as it goes through the internal or external auditory canal by unknown, likely auto-immune processes (Bell’s palsy) or tumors, lacerations, infections (Lyme, etc.)
In a PERIPHERAL CN VII lesion, the entire seventh nerve is likely damaged, so there is weakness of the upper AND lower facial muscles on that same side
Facial nerve lesions: peripheral vs central recap
In peripheral VII nerve interruption you will see full, unilateral facial weakness or paralysis on the same side as the nerve problem. Bell’s Palsy is a common example
In central (brainstem or cortex) interruption, only the lower face will be affected. The actual lesion will be on the opposite side if it originates in the cortex ( = cerebral hemisphere), and will be on the same side as the weakness if from the brain stem. Peripheral crossover innervation of upper motor facial nerves is intact.
CN VIII: Vestibulocochlear
Hearing and Balance: The auditory portion of CN VIII is tested by the physician directly; most disorders of the vestibular portion are assumed from a history of positional vertigo
Hearing can be determined subjectively by how well the patient seems to understand the physician’s words, or by the examiner rubbing her index and thumb together one inch lateral to each ear of the patient, or the patient’s hair can be rubbed about one inch lateral to each ear
Injured in concussion (TBI): CN I, VII, VIII can be seen
CN IX, X: Glossopharyngeal and Vagus nerves
CN IX is sensory to the soft palate, and CN X helps to raise the palate, so the Gag Reflex tests them both:
GAG REFLEX: Afferent: CN IX
Efferent: CN X
Glossopharyngeal (IX) provides taste on the posterior 1/3 of tongue
CN XI: Spinal Accessory Nerve
Innervation of the sternocleidomastoid and trapezius muscles
Resist the patient shrug both shoulders simultaneously
Resist a head tilting to each side
CN XII: Hypoglossal
Purely motor to only the tongue
Ask patient to stick out tongue (note if midline) and move side to side
Look also for atrophy or fasiculations of the tongue
In case of a CN XII peripheral lesion, the tongue deviates to the SAME SIDE
summary of screening neuro exam
The exam should contain assessment of:
Mental Status: alertness, appropriate responses, orientation to date and place
Cranial Nerves: acuity, pupillary light reflex, eye motion, hearing, facial strength
Motor: major muscle group strength upper and lower extremity, gait, coordination (finger to nose)
Sensory: test toes/feet – one modality of light touch, pain, temp or proprioception
Reflexes: DTR upper/lower, Babinski
