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Flashcards in Neurology/Neurosurgery Deck (107)
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1

In what common situation is a lumbar puncture contraindicated and why?

When there are signs of intracranial hypertension (e.g., papilledema), or suspicion for subarachnoid hemorrhage; doing so may cause uncal herniation and death.

Do a lumbar tap only after you have a negative CT or MRI of the head in these settings.

2

Describe the classic findings of cerebrospinal fluid (CSF) analysis in normal CSF in terms of

cells 

glucose

protein

pressure

Cells: 0-3 lymphocytes/mL

Glucose: 50-100 mg/dL

Protein: 20-45 mg/dL

Pressure: 100-200 mmHg

3

Describe the classic findings of cerebrospinal fluid (CSF) analysis in bacterial meningitis in terms of

cells 

glucose

protein

pressure

Cells: >1000 PMN/mL (normal = 0-3 lymphocytes/mL)

Glucose: <50 mg/dL (normal = 50-100 mg/dL)

Protein: 100 mg/dL (normal = 20-45 mg/dL)

Pressure: >200 mmHg (normal = 100-200 mmHg)

4

Describe the classic findings of cerebrospinal fluid (CSF) analysis in viral/aseptic meningitis in terms of

cells

glucose

protein

pressure

Cells: >100 lymphocytes/mL (normal = 0-3 lymphocytes/mL)

Glucose: normal mg/dL (normal = 50-100 mg/dL)

Protein: normal/slightly increased (normal = 20-45 mg/dL)

Pressure: Normal/slightly increased (normal = 100-200 mmHg)

5

Describe the classic findings of cerebrospinal fluid (CSF) analysis in pseudotumor cerebri in terms of

cells

glucose

protein

pressure

Cells: normal (normal = 0-3 Leukocytes/mL)

Glucose: normal (normal = 50-100 mg/dL)

Protein: normal (normal = 20-45 mg/dL)

Pressure: >200 mmHg (normal = 100-200 mmHg)

6

Describe the classic findings of cerebrospinal fluid (CSF) analysis in Guillain-Barre syndrome in terms of

cells

glucose

protein

pressure

Cells: 0-100 lymphocytes/mL (normal 0-3 lymphocytes/mL)

Glucose: normal (normal = 50-100 mg/dL)

Protein: >100 (normal = 20-45 mg/dL)

Pressure: normal (normal = 100-200 mmHg)

7

Describe the classic findings of cerebrospinal fluid (CSF) analysis in cerebral hemorrhage in terms of

cells

glucose

protein

pressure

Cells: ++RBC (normal = 0-3 Leukocytes/mL)

Glucose: normal (normal = 50-100 mg/dL)

Protein: >45 (normal = 20-45 mg/dL)

Pressure: >200 (normal = 100-200 mmHg)

8

Describe the classic findings of cerebrospinal fluid (CSF) analysis in multiple sclerosis in terms of

cells

glucose

protein

pressure

Cells: normal/slightly increased (normal = 0-3 Leukocytes/mL)

Glucose: normal (normal = 50-100 mg/dL)

Protein: normal/slightly increased (normal = 20-45 mg/dL)

Pressure: normal (normal = 100-200 mmHg)

9

Give a classic case description of multiple sclerosis.

insidious onset in white women aged 20 - 40 yo with exacerbations and remissions; common presentations

  • paresthesias and numbness
  • weakness and clumsiness
  • visual disturbances (decreased vision + pain caused by optic neuritis, diplopia as a result of cranial nerve involvement)
  • gait disturbances
  • incontinence and urgency
  • vertigo
  • emotional lability or other mental status changes
  • Internuclear ophthalmoplegia (disconjugate gaze in which the affected eye shows impairment of adduction)
  • scanning speech (spoken words are broken up into separate syllables separated by a noticeable pause and sometimes with stress on the wrong syllable)
  • possible Babinski sign

10

What is the most sensitive test for diagnosis of multiple sclerosis?

How is it treated?

How are acute exacerbations treated?

MRI - (most sensitive) -  shows demyelination plaques

LP - IgG/oligoclonal bands and myelin basic protein in CSF

Treatment: interferon, glatiramer, mitoxantrone, natalizumab, cyclophosphamide, methotrexate.

Acute exacerbations: glucocorticoids

11

What is Guillain-Barré syndrome?

What is the typical history a patient presents with?

How do these patients present?

How do you diagnose this?

Treatment?

GBS = postinfectious polyneuropathy.

History: history of mild infection (especially URI) or immunization roughly 1 week prior to onset of symptoms

Presentation: 

  • symmetric weakness/paralysis + loss of deep tendon reflexes + mild paresthesias that begin in the feet/legs 
    • loss of motor function with intact/minimally impaired sensation *hallmark*
  • As the ascending paralysis or weakness progresses, respiratory paralysis may occur.
  • Spirometry is performed to follow inspiratory ability; Intubation may be required.

Diagnosis: made by clinical presentation, but supportive tests can confirm the diagnosis

  • LP CSF is normal except for markedly increased protein
  • Nerve conduction velocities are slowed.

Treatment: usually resolves spontaneously, but plasmapheresis (for adults) and IVIg (for children) reduce the severity and length of disease.

12

What causes nerve conduction velocity to be slowed?

What are two potential causes of this?

Demyelination.

Watch for Guillain-Barré syndrome and multiple sclerosis as causes.

13

What causes an electromyography (EMG) study to show fasciculations or fibrillations at rest?

A lower motor neuron lesion (i.e., a peripheral nerve problem).

14

What causes an EMG study with no muscle activity at rest and decreased amplitude of muscle contraction upon stimulation?

Intrinsic muscle disease such as the muscular dystrophies or inflammatory myopathies (e.g., polymyositis). 

15

What is the most common cause of syncope?

What other conditions should you consider?

  • Vasovagal syncope - most common; classically is seen after stress or fear.
  • Arrhythmias and orthostatic hypotension - also common.
  • Hypoglycemia
  • Cardiac problems (arrhythmias, hypertrophic cardiomyopathy, valvular disease, tamponade)
  • Neurologic disorders (seizures, migraines, brain tumor)
  • Vascular disease (TIA, carotid stenosis)
  • Medications (anticholinergic agents, ß blockers, narcotics, vasodilators, alpha-agonists, antipsychotics).
  • idiopathic

16

localize the neurologic lesion for: Decreased or no reflexes, fasciculations, atrophy

Lower motor neuron disease (or possibly muscle problem)

17

localize the neurologic lesion for: Hyperreflexia, clonus, increased muscle tone

Upper motor neuron lesion (cord or brain)

18

localize the neurologic lesion for: Apathy, inattention, disinhibition, labile affect

Frontal lobes

19

localize the neurologic lesion for: Broca (motor) aphasia

Dominant frontal lobe*

(*The left side is dominant in more than 95% of the population (99% of right-handed people and 60% to 70% of left-handed people)

20

localize the neurologic lesion for: Wernicke (sensory) aphasia

Dominant temporal lobe*

(*The left side is dominant in more than 95% of the population (99% of right-handed people and 60% to 70% of left-handed people)

21

localize the neurologic lesion for: Memory impairment, hyperaggression, hypersexuality

Temporal lobes

22

localize the neurologic lesion for: Inability to read, write, name, or do math

Dominant parietal lobe*

(*The left side is dominant in more than 95% of the population (99% of right-handed people and 60% to 70% of left-handed people)

23

localize the neurologic lesion for: Ignoring one side of body, trouble with dressing

Nondominant parietal lobe*

(*The left side is dominant in more than 95% of the population (99% of right-handed people and 60% to 70% of left-handed people)

24

localize the neurologic lesion for: Visual hallucinations/illusions

Occipital lobes

25

localize the neurologic lesion for: Cranial nerves III and IV

Midbrain

26

Where do cranial nerves V, VI, VII, and VIII originate from?

Pons

27

Where do Cranial nerves IX, X, XI, and XII originate from?

Medulla

28

localize the neurologic lesion for: Ataxia, dysarthria, nystagmus, intention, tremor, dysmetria, scanning speech

Cerebellum

29

For delirious or unconscious patients in the ED with no history of trauma, for what three common causes should you think about giving empirical treatment?

  • Hypoglycemia (give glucose)
  • Opioid overdose (give naloxone)
  • Thiamine deficiency (give thiamine before giving glucose in a suspected alcoholic patient)
  • Other common causes: alcohol, illicit drugs, prescription drugs, diabetic ketoacidosis, stroke, and epilepsy or postictal state.

30

What are the classic differential points between delirium and dementia in terms of

onset

common causes

reversibility

attention

arousal level

What symptoms and signs do delirium and dementia have in common?

Common:

  • hallucinations
  • illusions
  • delusions
  • memory impairment (usually global in delirium, whereas remote memory is spared in early dementia)
  • orientation difficulties (unawareness of time, place, person)
  • “sundowning” (worse at night)