UWorld - Step 2 CK "Nervous System" Flashcards
When is plasmapheresis indicated in the treatment of MS?
When a patient with MS has disabling symptoms, you first treat with corticosteroids. If the steroids fail, then you administer plasmapheresis.
Trigeminal neuralgia is caused by ______________.
demyelination secondary to compression of the nerve
The ____________ nerve arises from the posterior cord and travels posterior to the humerus.
axillary
It is the unique pathway behind the humerus that makes it susceptible to injury in anterior dislocations.
Epidural hematoma is treated with _______________.
emergent craniotomy
A single brain abscess is most likely one of two organisms: ______________.
Staphylococcus aureus or Streptococcus viridans
Note: this usually results from infection of adjacent structures (teeth or sinuses).
Charcot-Bouchard aneurysms are the product of _________________.
hypertensive vasculopathy (typically bleeding into the basal ganglia or internal capsule)
To qualify as a febrile seizure, there needs to be no _____________.
identifiable cause of the seizure (such as meningitis, encephalitis, electrolyte abnormality, or mass)
What percent of those who’ve had one febrile seizure will develop epilepsy?
Less than 5%
What two studies would you order to help diagnose Guillain-Barré?
- LP (which will show high protein content with all other values normal)
- NCS (which will show decreased NCV)
What unique vital sign abnormality might those with Guillain-Barré have?
Orthostatic hypotension
List the triad of symptoms that suggest Wernicke encephalopathy.
- Gait disturbances
- Nystagmus
- Encephalopathy
For severe pain from cancer, give _____________.
short-acting opioids; for moderate pain, however, NSAIDs are more appropriate
What gait problems are associated with NPH?
Slow, broad-based, shuffling gait
Once again, what is the frequency of a Parkinsonian tremor?
4 to 6 Hz
How could you differentiate between an ACA stroke and a lacunar stroke that selected for the lower limb?
Lacunar strokes are so small that they generally are either pure motor or pure sensory, whereas ACA strokes are more often sensory and motor. Also, ACA strokes are more likely to induce urinary incontinence.
What is the first line treatment for IIH?
Acetazolamide +/- furosemide
Serial lumbar punctures can provide relief, but they are not preferred due to their risk of complications.
List the two big differences in the physical exams of cauda equina syndrome and conus medullaris syndrome?
- Conus medullaris syndrome affects the spinal cord and thus presents with upper motor neuron signs (hyperreflexia), while cauda equina syndrome affects the lower motor neurons and thus causes LMN signs (hyporeflexia, fasciculations).
- CES is asymmetric while CMS is symmetric.
Those with ____________ are more likely to develop ADHD.
absence seizures
NPH is thought to be caused by ________________.
the decreased absorption of CSF
Explain breath holding spells (BHS).
BHS occur in children ages 6 months to 2 years. They are episodes of breath holding after crying (often in response to an emotional stressor) during which the child passes out and turns blue. They are benign.
Cerebellar signs and T-wave inversions?
Friedrich’s ataxia
In uncal herniation, compression of the _____________ produces depression in consciousness.
reticular formation
Seizures are more typical of ________-tentorial masses, while clummsiness is more typical of _________-tentorial masses.
supra; infra
What kind of imaging might you do for a patient with café-au-lait spots?
Optic/orbital MRI (to evaluate for optic gliomas in NF-1)
If a patient with Parkinson’s presents with autonomic symptoms, then ___________ is a likely diagnosis.
Shy-Drager, also called multi-system atrophy
“Mouth is DRY? Think SHY!”
Describe the most common type of cerebral palsy.
Caused by prematurity, the most common form of cerebral palsy presents with bilateral equinovarus feet with spasticity.
A man presents with paralysis after a hike. What is the likely cause?
Tick-borne paralysis
In this disorder, ticks release a neurotoxin after feeding for 4-7 days. It causes paralysis without autonomic dysfunction (which does occur in Guillain-Barré syndrome). Importantly, this occurs without a prodromal or concomitant illness.
The most common side effects of Sinemet are _____________.
hallucinations, confusion, and dizziness – all CNS manifestations
How is botulism treated?
Equine antitoxin
The big worry about falling with an object in your mouth is ________________.
carotid dissection, which can result from oropharyngeal trauma
Remember, the oculomotor nerve has ____________ on the outside.
parasympathetics; this is why diabetic ischemic neuropathy can cause disrupted motor function (in the middle of the nerve, far from the arteries) without parasympathetic disruption (on the periphery, close to the arteries)
Headache, nausea, and eye pain are suggestive of _______________.
acute angle-closure glaucoma
Which is the more complicated presentation, galactokinase deficiency or galactose-1-phosphate uritdyl transferase deficiency?
G1PUTD
Galactokinase presents with only cataracts.
Remember, hypertensive vasculopathy presents with __________________.
isolated pure weakness or pure sensory loss
Hypertensive vasculopathy is also called lacunar stroke.
Hyporeflexia, weakness, and arrhythmia in an older person on a diuretic might indicate ____________.
hypokalemia
Bloodstream infection with lower-extremity paralysis might indicate _______________.
spinal epidural abscess
What is the mechanism of action of the only drug approved to treat ALS?
Riluzole is a glutamate antagonist.
What is the “classic triad” of brain abscesses?
- Fever
- Focal neurologic deficit
- Nocturnal headache
One of the best ways to prevent SIDS is _______________.
to have babies sleep on their backs (like the “Back to Sleep” campaign)
Remember that Guillain-Barré presents with ________-reflexia.
hypo
Hyperreflexia indicates UMN disorder.
What is athetosis?
Slow, writhing movements characteristic of Huntington’s
Describe the typical course of subarachnoid hemorrhage.
Initially, the person develops focal neurologic deficits over the area of bleeding. As time progresses, the intracranial pressure increases and causes signs of intracranial hypertension (vomiting, decreased alertness).
The best test for evaluating GBS is _________________.
spirometry (more accurate than peak flow meter)
How is cold therapy managed in heat stroke?
Immersion in cold water is preferred.
What can precipitate myasthenic crisis?
- Infection
- Surgery
- Pregnancy
- Medication changes
Which common OTC medication can potentiate the effects of warfarin?
Acetaminophen
What malignancy often presents with anti-NMDA encephalitis?
Ovarian teratoma
Once a patient with myasthenic crisis has been intubated, you should decrease __________________.
their cholinesterase inhibitors (to reduce secretions that might complicate their airway); at this point, plasma exchange and corticosteroids are indicated
What anticoagulation therapy is recommended for the treatment of septic emboli strokes?
Nothing
Antibiotics and observation are all that are needed.
Describe the causes and presentation of central cord syndrome.
- Caused by hyperextension of the neck (car crash)
* Presents with arm weakness
The most rapid-acting treatment of cluster headache is ______________.
oxygen therapy
Those with presbycusis will often complain of ____________.
difficulty hearing others when competing noises are present
___________ should be discontinued slowly.
Phenytoin
Rapid, transient vision loss can be caused by _________________.
atherosclerosis of the carotid arteries causing recurrent clots
The scariest complication of pseudotumor is ______________.
blindness due to optic nerve ischemia
Retinal detachment causes what visual disturbances?
Floaters or darkening vision from the periphery
Describe the presentation of cephalohematoma.
Occurring in neonates, cephalohematomas are periosteal bleeds that are limited to one bone. They present with swelling of just that bone.
Pronator drift is suggestive of what type of neurologic injury?
UMN weakness
In addition to focal neurologic deficits, what symptoms suggest brain tumor?
Nausea and headache that worsen at night
Why would you do a CT in a case of suspected meningitis?
If the patient also has vomiting or recent ear/sinus infection, then brain abscess is a possibility and LP could cause herniation.
If a person has hemisensory loss at about T10 from a stab wound, then they were likely stabbed at ______________.
T8
The fibers descend before exiting the spinal cord.
The most common site of ulnar entrapment is _____________.
the elbow (particularly in those who work at desks)
Hyperesthesia and athetosis can be a symptom of an infarction to what artery?
Posterior cerebral artery
Periorbital cellulitis and cavernous sinus thrombosis both present with swelling of the orbit. What physical exam finding can differentiate the two?
Cavernous sinus thrombosis presents with ophthalmoplegia due to impairment of the EOM nerves.
Those with impingement of the common peroneal nerve can walk on their ___________ but not their _____________.
toes; heel (because they can’t dorsiflex)
Tramtrack intracranial calcifications and ________________ are components of Sturge-Weber syndrome.
cavernous hemangiomas along the trigeminal distribution
Imagine Spider-Man –the “webber” –trying to stop a train made of calcium from crashing into a giant hemangioma.
The two neurologic signs of syphilis are ______________.
(1) pupils that don’t constrict to light but do to accommodation and (2) loss of vibratory and position sensation
What symptoms can help distinguish thrombotic from embolic causes of ischemic stroke?
Embolic strokes usually happen all at once (because the clot gets dislodged and stuck there), while thrombotic strokes fluctuate in symptoms and have precursor events (because of the narrowed carotid arteries).
Diabetic neuropathy can present with motor involvement. When might you be concerned about motor symptoms in ruling out other causes?
Motor symptoms are generally a later manifestation of diabetic neuropathy, so if a patient presents with early motor symptoms then you need to rule out other sources (like spinal compression).
Myotonic dystrophy has what inheritance pattern?
Autosomal dominant
What two labs can help you diagnose myopathies?
ESR and CK:
- ESR normal / CK normal: steroid-induced myopathy
- ESR normal / CK elevated: statin-induced myopathy or hypothyroid myopathy
- ESR elevated / CK elevated: autoimmune myositis
- ESR elevated / CK normal: polymyalgia rheumatica
_______________ is the most common complication of bacterial meningitis.
Hearing loss
What is the strongest risk factor associated with ischemic stroke?
Hypertension
Absence seizures typically last less than _______________.
20 seconds
The ________________ test is specific for myasthenia gravis.
ice pack
Cold helps slow the breakdown of acetylcholine. Classically, the ice pack is placed on the eyes of a person with ptosis for a couple minutes.
How should acute, severe pain in a former opioid addict be treated?
With IV morphine
Treatment in the acute setting is the same regardless of past substance abuse.
While _______________ is a common test for spinal stenosis, only about 10% of patients with spinal stenosis have a positive test.
the straight leg raise
Cluster headaches classically occur during __________.
sleep
What features make a brain cancer resectable?
- Single lesion
- Well-circumscribed
- On the periphery of the brain at the gray-white junction
At what age does myasthenia gravis typically occur?
Trick question!
Women: teens to 20s
Men: 50s to 70s
The basal ganglia controls the _____-lateral side of the body.
contra
In terms of the presentation of symptoms, how can you differentiate between intraparenchymal hemorrhage and subarachnoid hemorrhage?
Intraparenchymal hemorrhage slowly worsens, while SAH presents suddenly and stabilizes or improves.
Hemiparesis and hemisensory loss with gaze palsy are suggestive of _______________.
hemorrhage in the basal ganglia
If the stem talks about weakness and they show you a chest CT then the answer is ________________.
myasthenia gravis
The most common cause of lobar hemorrhage in adults over age 60 is _________________.
amyloid angiography
Optic neuritis causes _____________ of the optic nerve.
demyelination
What visual symptoms does optic neuritis cause?
“Washed-out” colors with an initial smudge in the visual field
The presence of _______________ in CSF is specific for CNS lymphoma.
EBV DNA
Why don’t patients with aminoglycoside toxicity experience vertigo?
Both vestibular organs are damaged equally.
____________ is first-line treatment for myasthenia gravis.
Cholinesterase inhibitors
Immune therapy is second-line.
Berry aneurysm rupture will show what on CT?
Bleeding into the basal cistern and insula
The arcuate fasciculus is in what two lobes?
Dominant frontal and parietal
