3-16 The Abnormal Neuro Exam Flashcards
What is the usefulness of the neurological history vs. the exam?
The neurological history, particularly in how the symptoms develop over time (minutes, days, weeks, years, etc.) helps determine the “WHAT” of diagnosis: stroke, infection, demyelination, tumor, seizure, trauma, etc.
The neurological examination helps to determine the “WHERE,” since we know so much about the FUNCTIONS of each segment of the central and peripheral neurological systems
What is the order of the neuro exam?
- Mental status examination
- Cranial nerves
- Cerebellum
- Strengths
- Deep tendon reflexes
- Sensory testing, as needed
- Gait, if possible
What does LOL AMEN mean?
Mental Status Exam
- Level of consciousness
- Orientation
- Language -these may be sufficient in most cases
- Attention
- Memory
- Executive/Intellectual function
- Non-dominant hemisphere
What are the 7 components of the MSE? Quick descriptor for each one?
- Level of consciousness: fully alert, lethargic/sleepy, stuporous, comatose
- Orientation: person, place, time
- Language: spontaneous/fluent/articulation, comprehension/commands, naming, repetition
- Attention: digit span, spelling, months/days forwards/backwards
- Memory: anterograde (recent), retrograde (distant)
- Executive/Intellectual function: verbal fluency, similarities, proverbs, estimates
- Non-dominant hemisphere: visual-spatial and construction skills, neglect, music
Why would you do a mental status exam?
It allows the diagnosis of important medical conditions, and helps in diagnosing and localizing these conditions:
Coma
Aphasia
Delirium
Apraxia and Agnosia
Dementia
Finding these abnormal conditions is far more helpful than simply concluding a patient as “altered mental status,” or as having a “changed mental status.”
Will performing a mental status exam rustle patient’s jimmies?
Generally not, no. (Unless they are standardized patients)
Second and third year medical students may feel most patients will somehow be offended by a mental status examination, or they will feel insulted
In reality, most patients do not have any objections to mental status examinations, unless they are physical uncomfortable or have significant psychiatric problems
Generally, how soon can you start MSE testing when dealing with a patient?
As soon as you start taking history.
it is always good to determine, tactfully, in advance, how much mental status testing can and should be done with each individual patient
Some mental status testing can be done as soon as the history is begun, in reality, as a student gains experience
(Pearl: can also document CN II-XII grossly intact by having a normal patient conversation. This only applies in the real world, though, not PCM.)
What are the various terms to describe LOC? What are the descriptions?
This is the subjective assessment of the physician:
ALERT: fully awake without stimulation, and able to cooperate in a history and physical examination
LETHARGIC: Patient prefers to sleep, but will stay awake with minimal verbal or physical stimulation
STUPOROUS: Patient requires repeated physical stimulation to stay awake
COMATOSE: A sleep like state in which the patient CANNOT be awakened: no further mental status testing is possible!
What is the significance of an abnormal LOC?
A lowered level of consciousness is always significant
Finding a previously alert patient is stuporous or comatose means something is seriously wrong, and is often an early sign of either a new disorder or a worsening of a known one
What problems could be present in a patient with an abnormal LOC?
- The patient has had a new problem such as a decline in the function of an organ system: CNS, heart, lungs, kidneys, liver
- A new medication has produced an adverse effect
- The bacterial infection has spread to the blood: sepsis
- The patient’s hematocrit, glucose or partial pressure of oxygen has declined, or the partial pressure of carbon dioxide has risen
What is the value of testing orientation in the MSE?
Orientation - test for person/name, place, and date/time.
Some physicians add a fourth factor: awareness of their reason for being in the hospital or the doctor’s office
May be affected by any of the medical conditions that cause delirium or dementia
Not always valuable in localizing brain disease, but traditionally tested in virtually all patients
How is orientation documented??
Documentation, if a normal level of consciousness and orientation: AOX3, which is a minimum mental status examination for patients with no apparent neurological disease
What types of abnormal language problems might be picked up on MSE?
Aphasia
Broca’s aphasia
Wernicke’s aphasia
Anomia, (sometimes agraphia too)
Dysarthria
What does aphasia indicate?
Aphasia is ALWAYS an indication that the patient’s DOMINANT HEMISPHERE is impaired:
stroke, hemorrhage, seizure, or trauma, if it is a sudden result,
or a tumor or dementia, if GRADUAL over many months or years
Describe the location and symptoms of Broca’s aphasia.
BROCA’S APHASIA: frontal lobe, usually accompanied by hemiplegia, retained understanding, brief “telegraphic” output
Describe the location and symptoms of Wernicke’s aphasia.
WERNICKE’S APHASIA: less common, superior temporal lobe, fluent, poor understanding
What do Broca’s aphasia and Wernicke’s aphasia have in common?
Both have ANOMIA, or inability to name objects, and inability to repeat
Both usually have limitations in writing, AGRAPHIA
Describe dysarthria, and what causes it.
DYSARTHRIA
slurred or thick speech
may be due to disease of either hemisphere, and sometimes the brainstem, or may be due to a decline in consciousness or medication effect,
or diseases of the larynx or mouth
How do you test language function in patients?
§First of all, listen to patients, beginning with your history taking
§Have patients REPEAT words or simple phrases
§Have patients READ a paragraph
§Have patients WRITE a sentence
§Have patients carry out two or three step functions you read to them: “Close your eyes, stick out your tongue, and raise your right arm”
§Have patients NAME some simple objects, such as a pen, a comb, a cup, etc.
What is apraxia?
Apraxia: Loss of skilled movements and gestures (procedural memory)
loss of complex, multi-step actions, such as combing the hair, brushing the teeth, shaving or putting on makeup, or even getting dressed
Patients cannot carry out these tasks, even though they have sufficient motor and sensory functions to do them
Why does apraxia happen?
Partial damage to the dominant lobe
Likely due to damage to connections between different sites in the cerebral cortex
Common in stroke survivors and in severely demented people
What is Gerstmann Syndrome?
a syndrome specifically caused by damage to the angular gyrus of the dominant PARIETAL lobe
What are the symptoms of Gerstmann syndrome?
- ACALCULIA: Inability to understand numbers or to calculate
- AGRAPHIA: Inability to write
- Inability to distinguish the left and right sides of the patient (or of the examiner)
- Inability to distinguish the individual fingers
What does the loss of attention suggest?
MSE: Attention (Concentration)
may suggest the beginning of delirium
How can attention be evaluated?
- Do the months (or the days of the week) forward and then backwards
- Serial sevens, subtracting seven starting from 100
- Read a series of letters, asking the patient to raise his hand when he hears the letter “A”
- Have the patient spell “WORLD” forwards and backwards
What is delirium? What are the symptoms?
Delirium: the acute confusional state
May be referred to also as ENCEPHALOPATHY
There may be agitation (aggressive and dangerous behavior), sometimes hallucinations, tremors, wide fluctuations in blood pressure and pulse rate suggesting autonomic nervous system involvement
Usually there is hyper-reactivity to environmental stimulation, or at other times, extreme sleepiness
What does delirium suggest, clinically? What is it often due to?
Delirium suggests in most cases a diffuse systemic problem is affecting large sections of the brain, such as both hemispheres or the entire brainstem
Often due to INFECTIONS INCLUDING SEPSIS, NEW MEDICATIONS (especially opioids), decline of respiratory, hepatic or renal function, meningitis or encephalitis, or ALCOHOL WITHDRAWAL
§Localizes to widespread dysfunction of the entire brain
How do you do MSE testing in a patient with delirium?
Patients with delirium can not reliably be tested for any later parts of the MSE beyond attention, and even their language function may be partially impaired
They are too inattentive to do memory testing, and executive and nondominant hemisphere functions are also damaged
The physician cannot conclude that a delirious patient has these other MSE abnormalities until the delirium clears
What is delirium likely to be comorbid with?
DEMENTED PATIENTS ARE MORE PRONE TO DELIRIUM THAN NONDEMENTED PATIENTS, and sometimes the diagnosis of dementia is first considered in an older patient who has had a first episode of delirium
What regions of the brain does memory testing in the MSE highlight?
Localizes to BILATERAL medial temporal lobe damage, particularly the HIPPOCAMPUS, but the amygdala and the frontal lobes are essential for good memory function
How does Alzheimer’s disease affect memory?
Alzheimer’s disease almost always begins as a progressive loss of memory; first recent, and then distant memory
What is the difference between anterograde and retrograde memory?
ANTEROGRADE: recent memory, or the ability to store new information, up to a few days
RETROGRADE: more distant memories, including autobiographical (dates of graduation, marriage, etc.) or historical (date of wars, elections, sports, etc.)
How is anterograde memory tested?
Testing recent memory: “Please listen to these 3 words, and then repeat them. I will ask you to remember them soon.” Memorize your OWN 3 words, and ask them in approximately 3 – 10 minutes. Some patients deserve a second try.
Occasionally a normal patient will recall only 2/3, but recalling 0, or 1 words on two attempts is pathologic
In addition to recalling 3 words, what are some other methods of testing anterograde memory?
Also tested by:
- “How long have you been in the hospital?”
- Giving a patient a brief story to remember, perhaps three or four sentences long
- “What did you have for breakfast (or lunch, dinner)?”
- Hide three objects in your examining room as the patient watches, and then ask the patient where they were hidden
How and why is retrograde memory tested?
Less often tested, mostly for confirming a diagnosis of dementia
Examples:
- When did you graduate from high school?
- When did you get married?
- How many children do you have?*
- When did you retire?
- When did the Vietnam War (or World War II) occur?
- Can you name some recent presidents?
What is executive function?
These are the higher functions of the cerebral cortex
They provide “content” to a patient with consciousness
Also called “cognitive ability”
Includes the important functions of insight, judgement, and making important decisions
How is executive function tested?
Can be tested in many ways:
Recent news events, recalling recent Presidents or the current governor of the state, general fund of knowledge (distances, geography), determining similarities of two objects, the interpretation of common proverbs
Why is verbal fluency used in the MSE?
Tests executive function, an excellent test of how the frontal lobes retrieve information from the temporal lobes
How is verbal fluency tested?
- Ask the patient to name as many members of a category as he can:
Examples: animals, girls’ or boys’ names, states in the United States, cities in Colorado, things you can buy in a grocery store or an apartment store, or words beginning with the letter A, F, S, etc.
Most healthy young patients can name 20 or more in one minute, while demented elderly patients will name less than TWELVE in one minute
What is diagnostic of dementia?
Along with possible amnesia, aphasia, apraxia, and decline in the functions of the nondominant hemisphere, the loss of executive function is diagnostic of DEMENTIA;
A more gradual, subtle loss of all of the higher cognitive abilities, which develops over months or years
Unlike delirium, dementia is usually irreversible
What is the typical progression of loss of function in dementia?
Patients will lose their memory in most types of dementia, their ability to do the activities of daily life, their social and occupational skills, and ultimately they will be unable to live independently
As dementias progress over years, the earlier aspects of the mental status exam will also suffer, such as orientation and attention, language, and finally even level of consciousness
What does the parietal lobe do?
§Parietal lobe: visual-spatial skills, constructions, awareness of one’s own body or the environment, especially to the left visual field
What does the temporal lobe do?
Temporal lobe: loss of musical abilities and a tendency to psychiatric disturbances such as psychosis, depression and bipolar disorder, anxiety
What does the occipital lobe do?
Occipital lobe: left homonymous hemianopia and prosopagnosia, inability to recognize faces
What is agnosia?
recognition deficit
Name 4 agnosias, and what they are.
Hemispatial neglect: not appreciating that there are people or objects in the left side of the room or on the left side of a drawing or photograph, in spite of preserved vision
Anosognosia: the inability to recognize hemiparesis in a patient’s left arm or left leg; very common immediately after a stroke
Dressing agnosia: inability to button clothes or put an arm in a sleeve on the left side, or to shave or put on make up on the left side of the face
Prosopagnosia: inability to recognize familiar faces, congenital or acquired
What does a lack of constructional skills indicate?
Again, a sign of nondominant (right) parietal lobe damage
May also reveal hemispatial neglect
Very much impaired in dementias such as Alzheimer’s Disease
How are constructional skills tested?
Can be tested by having the patient draw, or copy, simple and then increasingly complicated figures, such as a circle, a square, a cube, a house, or a clock with all of the numbers
What is the rationale behind testing the CNs? What areas are vulnerable to small changes?
Long known to be a way of localizing a disease to the brainstem, other portions of the head, including the face, or sometimes the neck and upper thorax
The brainstem and the face are especially vulnerable to seemingly small changes, seen with an abnormal cranial nerve examination finding
What do widespread abnormalities of the brainstem lead to?
Widespread abnormalities of the brain stem lead to loss of consciousness, diffuse weakness of the arms and legs, loss of respiration, and eventually loss of cardiac function
What are some important things to check with CN II?
The most important thing to check with CN II is the visual acuity
Pupillary reactivity and funduscopy are also important
What are some changes in the visual field that were mentioned? What can they indicate?
Loss of vision is always a catastrophe for patients, even if it is “only” loss of distance vision or reading ability
Even more serious is the total loss of vision in one o both eyes, or a completely homonymous hemianopia
Tunnel vision, or bitemporal hemianopia, points to a lesion around the pituitary gland
What are the abnormal pupillary reactions?
Loss of the pupillary reflex indicates a problem with the afferent portion (CN II) and/or the efferent portion (CN III)
A pupil that does not react at all to light may be caused by blindness, optic neuritis (sometimes due to multiple sclerosis), an optic nerve tumor, or when it is dilated and unreactive, due to Adie’s pupil (polyneuropathy, especially in diabetics)
A unilateral significantly dilated pupil may be due to a lesion of CN III, including herniation of the ipsilateral cerebral hemisphere!
What can occasionally cause an abnormal CN III finding?
Occasionally due to strokes, diabetes, or even migraine, when temporary
A. These disorders usually “spare the pupil,” if due to ischemia inside of the midbrain
What types of CN III abnormalities will not spare the pupil?
The pupil is NOT spared in lesions from outside the midbrain: tumor, herniation of the ipsilateral cerebral hemisphere due to a large tumor or hemorrhage
A. Also can be caused by a life threatening aneurysm, ruptured or unruptured, of the posterior communicating artery
What is ptosis? What causes it?
Droopiness of the upper eye lid , via the LEVATOR PALPEBRAE SUPERIORIS,
may due to CN III lesions: tumor, aneurysm or diabetic infarction of the midbrain
May also be part of a neuromuscular disease such as myasthenia gravis
May be found in Horner’s Syndrome, due to weakness of Mueller’s muscle, from damage to the unilateral SYMPATHETIC NERVOUS SYSTEM
Sometimes from trauma or prior eye surgery
What is special about CN IV? What mm does it serve?
CN IV, the trochlear nerve, is the only completely crossed cranial nerve,
serving the contralateral superior oblique muscle,
damaged by trauma or congenital disease
How is CN IV tested? What other mm helps with eye abduction?
have patient look down and in
The eye is also minimally abducted by the superior oblique
What mm does CN VI innervate? What does damage to it indicate?
CN VI, the abducens nerve, serves the ipsilateral lateral rectus muscle, and can indicate localized disease of the pons or the skull, or increased intracranial pressure from tumors or trauma anywhere inside the skull
What are the fxns of CN VII?
Almost entirely motor, to the muscles of facial expression
But also taste of anterior tongue, lacrimation and salivation
Limitation of hearing damage from loud noise by contraction of the stapedius muscle
How is CN VII tested? What do lesions manifest as?
Tested by closing the eyes, raising the eyebrows, for the UPPER FACE
Tested by smiling or pursing the lips for the LOWER FACE
Many people have lower facial asymmetries, from incompletely-healed central or peripheral lesions
What is the difference between central and peripheral CN VII palsies?
PERIPHERAL ; in the course of the facial nerve after it has left the pons; BOTH the upper and the lower facial muscles on that side are impaired: these are peripheral seventh nerve palsies
- If truly idiopathic, it is called Bell’s Palsy
CENTRAL; the lesion is in the pons or upper brain stem, or far more commonly in the contralateral cerebral hemisphere, and ONLY the lower facial muscles are impaired
Still unclear why this occurs, perhaps because the lower facial muscles receive innervation from BOTH SIDES of the motor strip in the frontal lobes
What is the most important fxn of the cerebellum? What side of the body does it manifest on? Why?
Mostly important for coordination of movements on the SAME SIDE: this is due to the “double cross” of cerebellar efferents crossing over in the brainstem and going to the contralateral thalamus and contralateral motor cortex; descending corticospinal fibers will cross in the medulla oblongata
What do people with cerebellar problems often have?
Patients have ATAXIA of many movements which require rapidity and precision, especially the limbs, but also extra-ocular movements
Ataxia actually means a lack of coordination due to cerebellar disease, and not simply trouble walking
What are some ways to test the cerebellum?
There are many ways to test each cerebellar hemisphere
Remember that because of the “double cross,” CEREBELLAR DISEASE IN ONE LOBE ALWAYS PRODUCES ABNORMALITIES ON THE SAME SIDE OF THE BODY
Finger to nose, extending the patient’s arms completely
Rapid alternating movements
Knee to ankle movements of the opposite leg
Why is damage or injury to the cerebellum medically serious?
Strokes and hemorrhages, or expanding tumors of one cerebellar hemisphere may cause rapid death due to BRAIN STEM DAMAGE AND BLOCKAGE OF THE FOURTH VENTRICLE’S CSF FLOW
What are some common causes of hemisphere damage to cerebellum?
One hemisphere may be damaged commonly in strokes, hemorrhages, primary and metastatic tumors, or trauma,
Acute cerebellar diseases, and chronic bilateral cerebellar diseases, are likely to affect the patient’s ability to walk
Ataxia means a lack of coordination due to diseases of the cerebellum: it DOES NOT mean “trouble walking”
What are some causes of bilateral cerebellar diseases?
diseases may be due to familial cerebellar degeneration, alcoholism, certain medications, mercury, multiple sclerosis
What does the Romberg test actually test? How is it performed?
Upright posture requires 3 functions:
- Vision
- Cerebellum
- Posterior columns
Actually, a better test of the POSTERIOR COLUMNS (gracile and cuneate fasciculi) than the cerebellum; best done after other cerebellar tests are completed
Patients are ask to stand with their eyes open, and then tested for falling when asked to close their eyes
What does strength testing test?
Test the strengths of the major “GROUPS” of muscles in the upper and lower extremities
Where do you do strength testing in the upper extremity?
Check the upper extremities at
- Shoulders (deltoids)
- Elbow flexion and extension (biceps, triceps)
- Wrist flexion and extension (“hand grip” is usually weakened by cerebral disease, but may seem normal even with serious cervical spine or root disease)
Where do you test strength in the lower extremities?
Check the lower extremities at:
- Hips (flexion via the iliopsoas, etc.)
- Knees (extension, and less commonly flexion)
- Ankles (DORSIFLEXION via anterior tibial, peroneal, etc., and PLANTAR FLEXION via gastrocnemius, soleus)
How is mm strength documented/graded?
The numerical quantification of strengths has weaknesses (pun intended)
Strengths are numbered 0 to 5, with the most numbers for severe weakness ( 0 to 3), and only 4 and 5 for mild weakness
0/5: absolutely no movement in a group
1/5. minimal, or “flicker” of movement
2/5. minimal horizontal movement, but no movement against gravity
3/5. Some movement against gravity
4/5. Moderate strength against gravity and some resistance
5/5. Normal contraction
How is mm weakness regarded by patients? Physicians?
Very important to patients, of course, especially if it is a sudden weakness
Physicians commonly overlook subtle weaknesses
Patients who complain of being “weak all over” are often dismissed as hypochrondriacs
What can weakness in mult parts of the body indicate?
Weakness in multiple parts of the body CAN be due to a somatoform disorder,
but can also be due to upper cervical spine diseases,
neuromuscular diseases such as myasthenia gravis, myopathies or acute demyelinating polyneuropathy (the Guillain-Barre syndrome)
What are some types of localized weakness? Where is the pathology in each type?
Quadriplegia: disease of the upper or mid cervical spine, or both of the corticospinal tracts of the brain stem
Hemiplegia: disease of one cerebral hemisphere or one side of the brainstem along the corticospinal tract
Paraplegia: disease of the spinal cord in the thoracic or high lumbar regions
What does weakness of 1 arm indicate? 1 leg?
Weakness of one arm: cervical spine disease or the brachial plexus, or some strokes
Weakness of one leg: lumbar spine disease or the lumbar sacral plexus, or, rarely a stroke (anterior cerebral artery infarct)
In addition to the X/5 scale, what else is important in documenting mm testing?
When testing strengths, it may be useful to note the BULK or size of certain important muscles
Also, the TONE of the arm or leg, which is resistance to stretch, increased in CNS causes of weakness
Look for evidence of FASCICULATIONS: quick muscle jerks or twitches, caused by peripheral nerve disorders, but sometimes idiopathic and benign
How are DTRs graded?
All DTRs are traditionally graded 0 – 4
0: no reflex
1: diminished reflex
2: average reflex
3. increased reflex, but only one beat
4. increased reflex with CLONUS: two or more beats
A reflex of 0 is usually pathologic, but a reflex of 4 is always pathologic
What is the babinski test? How is it done, and what is abnormal?
There is NO Babinski TEST!!!
There is a plantar reflex, in which the sole of each foot is quickly stroked from the heel to the toes
The Normal Plantar Reflex is FLEXION of the big toe
The Abnormal Plantar Reflex is EXTENSION of the big toe, sometimes with separation or “fanning out” of the smaller toes
This Abnormal response, with big toe extension, is called a:
BABINSKI SIGN
What are the signs of UMN disease?
Upper motor neuron: brain or spinal cord:
Increased reflexes, spasticity, only delayed atrophy of muscles, Babinski signs
What are the signs of LMN disease?
Lower motor neuron: motor neuron, neuromuscular junction, muscle itself:
Decreased reflexes, atrophy within weeks, sometimes fasciculations, no Babinski signs
Why is distinguishing UMN from LMN disease helpful?
This can be a very helpful way of determining the cause of weakness, knowing there are two distinct categories
What can cause DTRs to become abnormally decreased?
If decreased, may be due to diabetes mellitus, hypothyroidism, vitamin B12 deficiency, exposure to heavy metals or some organic chemicals, increased production of immunoglobulins, auto-immune diseases
What can cause DTRs to become abnormally increased?
If increased, may be due to lesions of the corticospinal tracts (upper motor neuron weakness) especially in the spinal cord or brain stem, less so in the cerebral hemispheres, or hyperthyroidism, or even with a normal pregnancy
What can cause sensory loss?
Sensory loss can be due to disease at any level of the central or peripheral nervous systems:
Cerebral hemisphere (sensory cortex or subcortical connecting fibers, including the thalamus): numbness of the entire contralateral face, arm or leg
Thalamus
Brainstem: numbness of the face, sometimes bilateral
Spinal cord: CAUSES A SENSORY LEVEL
Peripheral nerves or roots of nerves are commonly affected, as in radiculopathies: limited loss of fine touch within the limited distribution of a single nerve or DERMATOME
How should the sensory exam be focused?
By the time the physician gets to sensory testing, there should already be some sense of where the patient’s disease is located. If not, the sensory examination can still be very helpful. Direct your sensory examination based upon your suspicions, or the sensory examination may be time-consuming ad useless. I recommend it be your final, or next-to-last area in the neurological examination
What kinds of abnormal gait are there?
Not always necessary, but it can be very helpful:
Hemiplegic gait, with circumduction, inability to bring the leg all the way in
Spastic gait: Limited ability to bend at the hips and knees
Festinating gait: slow with the first steps, then faster and faster, and out of control, in Parkinson’s disease
Inability to stand or walk at all: spinal cord disease or an acute cerebellar lesion such as stroke or hemorrhage
