Uworld Nervous system Flashcards
Ascending paralysis + autonomic dysfunction (tachycardia, urinary retention, and arrythmia). CSF exam is typically abnormal and may show albuminocytologic dissociation (high protein with few cells)
Guillain Barre syndrome
Treatment of Guillain Barre
IVIG or plasmapheresis
This is characteriezed by rapidly progressive ascending paralysis (which may be asymmetrical), absence of fever and sensory abnormalities, and normal CSF examination.
- Tick borne paralysis
- Ticks must feed for 4-7 days and are typically found on patients after meticulous searching
- Removal of the tick results in spontaneous improvement in most patients
Describe the epidemiology of Alcoholic cerebellar degeneration?
- > 10 years heavy alcohol use
- Degeneration of Purkinje cells (cerebellar vermis)
Describe how alcohol cessation and nutritional supplementation effects alcoholic cerebellar degeneration?
- prevents disease progression
- Ambulatory difficulties do NOT typically improve
- Patients therefore usually benefit from ambulatory assist devices such as canes or walkers
What does protamine sulfate reverse?
Heparin
Patients who develop serious bleeding (e.g. intracerebral hemorrhage) due to excess anticoagulation with warfarin (high INR) should have their anticoagulation reversed with what?
- IV vitamin K and Prothrombin complex concentrate to reduce the risk of death and permanent disability
- FFP can be considered if PCC is not available; however it takes longer to prepare/administer and requires more volume infusion compared to PCC
what are the common causes of vertigo?
- Meniere Disease
- BPPV
- Vestibular neuritis
- Migraine
- Brainstem/cerebellar stroke
Pronator drift is a physical exam finding that is relatively sensitive and specific for what?
-upper motor neuron or pyramidal/corticospinal tract disease
What dysfunction typically results in extrapyramidal signs, such as resting tremor, rigidity, bradykinesia, and choreiform movements
Basal Ganglia dysfunction
What dysfunction usually causes ataxia, intention tremor, and impaired rapid alternating movements?
cerebellar dysfunction
Drug-induced hyperammonemia can be observed in patients using valproic acid and usually presents with what?
- encephalopathy (e.g. confusion, lethargy)
- neuromuscular findings (e.g. bradykinesia, asterixis)
Site of hemorrhage? - Contralateral hemiparesis and hemisensory loss
- Homonymous hemianopsia
- Gaze palsy
- Eyes deviate towards lesion
Basal ganglia (putamen)
Site of hemorrhage? Usually NO hemiparesis
- facial weakness
- Ataxia and nystagmus
- Occipital headache and neck stiffness
cerebellum
Site of hemorrhage? -Contralateral Hemiparesis and hemisensory loss
- nonreactive miotic pupils
- upgaze palsy
- Eyes deviate TOWARDS hemiparesis
Thalamus
Site of hemorrhage? - Contralateral hemiparesis (frontal)
- Contralateral hemisensory loss (parietal)
- Homonymous hemianopsia (occipital)
- Eyes deviate AWAY from hemiparesis
- High incidence of seizures
-Cerebral lobe
Site of hemorrhage? Deep coma and total paralysis within minutes
-Pinpoint reactive pupils
Pons
This is a glutamate inhibitor that is currently approved for use in patients with ALS
- Riluzole
- Although it cannot arrest the underlying pathologic process, it may prolong survival and the time to tracheostomy
Patient with acute painless monocular vision loss that persists for several hours likely has what?
central retinal artery occlusion
Adult with one eye Down and out, Normal sized, reactive pupil, and ptosis has what?
-What is the most common cause in adults?
- Oculomotor nerve palsy
- Ischemic neuropathy due to poorly controlled DM
In oculomotor nerve palsy for DM ischemia, describe who pupillary response is preserved?
- Because the inner somatic fibers are farther from the blood supply, they are more susceptible to ischemic injury
- paralysis of the levator muscle and the 4 EOMs
- Superficial parasympathetic fibers innervate the sphincter of the iris and the ciliary muscles controlling pupil dilation
How do you differentiate CNIII palsy from compression vs. ischemia
-Compression would effect the outer parasympathetic fibers as well leading to an abnormal pupillary response (mydriasis)
Brain death is a clinical diagnosis. The characteristic findings are what?
- Absent cortical and brain stem functions
- The spinal cord may still be functioning; therefore, deep tendon reflexes may be present
Describe the treatment options for Restless legs syndrome?
- Iron supplementation for iron deficiency (serum ferritin <75)
- Conservative measures
- dopamine agonists (pramipexole)
- Alpha-2-delta calcium channel ligands (e.g. gabapentin)
What is pseudodementia?
Severe depression in the elderly can present with a dementia similar to Alzheimer’s disorder
This disease is similar in presentation to Alzheimer’s disease, except that it presents at an earlier age. It is seen more frequently in females, and frequently causes personality changes due to involvement of the frontal lobers; Howevere it does not cause any extrapyramidal symptoms . . No movement disorders
Pick’s disease
This occurs due to occlusion of the posterior inferior cerebellar or vertebral artery. Patients develop loss of pain and temp over the ipsilateral face and contralateral body, ipsilateral bulbar muscle weakness, vestibulocerebellar impairment (e.g. vertigo, nystagmus), and Horner’s syndrome. Motor function of the face and body is typically spared
Lateral medullary infarct (Wallenberg syndrome)
within what time from of ischemic stroke can you give IV alteplase?
-within 3.5 to 4 hours of symptom onset and no contraindications
What is the only antiplatelet agent that is effective in reducing the risk of early recurrence of ischemic stroke
Aspirin
Describe CT findings in acute ischemic stroke
- Ct scan of the brain may not show ischemic changes in the first 24 hours
- The main role of CT scan in this period is to rule out hemorrhagic stroke rather than diagnose ischemic stroke
This is a vision threatening condition that may be associated with certain medications (e.g. anticholinergics for Parkinson disease) or arise spontaneously. Manifestation include the sudden onset of severe eye pain, nausea, vomiting, unilateral conjunctival injection, and a dilated pupil with poor light response. Untreated, patients with this can develop permanent vision loss within 2-5 hours of symptom onset. Urgent ophthalmologic consultation is required
Acute angle-closure glaucoma
Mild to moderate cancer-related pain can usually be managed with nonopioid analgesics (e.g. acetaminophen, NSAIDs). However, for severe pain, or if initial intervention are not effective, what should be offered?
- short acting opioids (morphine, hydromorphone)
- If the patient has pain requiring frequent dosing or if bedtime dosing does not provide adequate relief through the night, a long-acting opioid (e.g. sustained release morphine) may be added
The clnical features of foodborne botulism are acute onset within 36 hours of ingestions: Bilateral cranial neuropathies, Blurred vision, diplopia, facial weakness, dysarthria, dysphages, symmetric descending muscle weakness, diaphragmatic weakness with respiratory failure . . how do you diagnose and treat?
- Serum analysis for toxin
- Equine serum heptavalent botulinum antitoxin
Describe the evaluation of corneal abrasian
- Penlight test to document pupillary function and inspect for foreign body
- Visual acuity with ophthalmology referral if decreased
- Florescein exam after above tests to show corneal straining defect
In a patient with corneal abrasian on exam but no pain, what nerve is likely affected
-CN V1 . .ophthalmic of trigeminal –>corneal anesthesia
This presents with transient vision loss lasting a few seconds iwth changes in head position
- Papilledema caused by increased ICP
- required urgent diagnostic evaluation (e.g. ophthalmologic exam, neuroimaging, and/or lumbar puncture) as persistent papilledema can lead to vision loss
CT scan without contrast is the preferred initial imaging study for subarachnoid hemorrhage and typically reveals what?
acute hemorrhage (high density signal) surrounding the brainstem and basal cisterns
What medications are linked to possible idiopathic intracranial HTN
- tetracyclines
- Hypervitaminosis A (maybe from retinoic acid for acne)
What nerve palsy is most common with idiopathic intracranial HTN (pseudotumor cerebri)
CN VI
What brain finding is the hallmark of prolonged seizures and can lead to persistent neurologic deficits and recurrent seizures
Cortical laminar necrosis from excitatory cytotoxicity
Side effects of Levodopa plus Carbidopa
- Somnolence, confusion, hallucinations (older patients)
- Dyskinesia
Side effects of amantadine
- ankle edema
- livedo reticularis
Side effects of Apomorphine, bromocritine, pramipexole, or ropinirole
- somnolence, hypotension, confusion
- Hallucinations (older patients)
Side effects of Entacapone or tolcapone
- Dyskinesia
- hallucinations
- confusion
- nausea
- orthostatic hypotension
Acute angle closure glaucoma is more common in women (especially age > 40), Asian and Inuit populations and individuals with farsightedness. Patients typically develop rapid onset of what symptoms?
- Severe eye pain
- may see halos around lights
- The affected eye will appear injected
- pupil will be dilated and poorly responsive to light
- Patients can also develop tearing and headache with subsequent nausea and vomiting as the intraocular pressure increase
Acute angle-closure glaucoma commonly occurs as a response to pupillar dilation from what?
- meds (e.g. anticholinergics, sympathomimetics)
- or another stimulus (e.g. dim light)
Describe how to diagnose myathenia gravis
- Bedside: Edrophonium (Tensilon) test, ice pack test
- Acetylcholine receptor antibodies (highly specific)
- CT scan of chest to evaluate for thymoma
what is the classic triad of Spinal epidural abscess
- Fever (about 50%)
- Focal/severe back pain
- Neurologic findings (e.g. motor/sensory change, bowel/bladder dysfunction, paralysis)
How do you diagnose a Spinal epidural abscess?
- Elevated ESR
- Blood and aspirate cultures
- MRI of the spine**
This tremor occurs in the legs immediately on standing and is relieved by sitting down
- Orthostatic tremor
- considered to be a variant of essential tremor
Lung cancer is the most common neoplasm to metastasize to the brain and may present with headache, FND, cognitive change, or seizure. An MRI of the brains typically shows what?
Multiple, well-circumscribed lesions with vasogenic edema at the gray and white matter junction
Deficits in ACA stroke
- contralateral motor and/or sensory deficits
- More pronounced in LOWER LIMB
- May include urinary incontinence
This causes Gait apraxia which is a magnetic freezing gait. Start and turn hesitation . . what are associated signs
-Frontal lobe degernation and normal pressure hydrocephalus
Describe the gait abnormality that can be caused by lesions to the pyramidal tract or corticospinal tract
- spastic ataxia
- gait appears stiff or rigid with circumduction (The spastic leg is abducted and advanced while in extension and internal rotation) and plantar flexion of the affected limb
What is the initial imaging study of choice in patients with unprovoked first seizure to exclude acute neurologic problems (e.g. intracranial or subarachnoid bleed) that may require urgent intervention
- CT scan of brain WITHOUT contrast
- MRI is more sensitive than CT in identifying most structural causes of epilepsy and is the neuroimaging modality of choice in elective situations
Suspect what in an HIV-infected patient with an altered mental status, EBV DNA in the CSF, and a solitary, weakly ring-enhancing periventricular mass on MRI
Primary CNS lymphoma
Signs and symptoms of myasthenic crisis
- Increased generalized and oropharyngeal weakness
- respiratory insufficiency/dyspnea
Precipitating factors of myasthenic crisis
- Infection or surgery
- Pregnancy or childbirth
- Tapering immunosuppressive drugs
- Medications (e.g. aminoglycosides, beta blockers)
Treatment of Myasthenic crisis
- Intubation for deteriorating respiratory status
- Plasmapheresis or IVIG, and corticosteroids
This is a degenerative disease characterized by 1) Parkinsonism, 2) Autonomic dysfunction (postural hypotension, abnormal sweating, disturbance of bowel or bladder control, abnormal salivation or lacrimation, impotence, gastroparesis, etc), 3) Widespread neurological signs (cerebellar, pyramical or lower motor neuron)
Multiple system atrophy (Shy-Drager syndrome)
This is an autosomal recessive dz seen predominantly in children of Ashkenazi Jewish ancestry. It is characterized by gross dysfunction of the autonomic nervous system with severe orthostatic hypotension
Riley-Day syndrome or familial dysautomonia
Subclavian Steal syndrome occurs due to stenosis or occlusion of what vessel
proximal subclavian artery leading to reversal of blood flow in the ipsilateral vertebral artery
What is one of the few conditions that may present with trigeminal neuralgia bilaterally?
MS
-This occurs due to demyelination of the nucleus of the trigeminal nerve or the nerve root
Rebleeding and Vasospasm are 2 complications of subarachnoid hemorrhage. Describe the difference in tie frame and the presentation
- Rebleeding is the major cause of death within the first 24 hours of presentation, especially within the first 6 hours of untreated SAH . . surgical repair practically eliminates this risk
- Vasospasm can occur in up to 30% of SAH Patients from days 3-10 after presentation and is the major cause of delayed morbidity and death. It is likely caused by arterial narrowing at the base of the brain due to degradation of the bleed and its metabolites and can lead to cerebral infactions
What imaging detects vasospasm in Subarachnoid hemorrhage and what medication can prevent it?
- CT angio
- Nimodipine
Lesions to this lobe of the brain can cause expressive (Broca’s) aphasia, contralateral hemiparesis due to involvement of the primary motor cortex, and contralateral apraxia due to involvment of the supplementary motor cortex
Dominant Frontal Lobe
Patients with MS exacerbation and disabling symptoms are typically treated with what?
glucocorticoids (e.g. IV methylprednisone)
What treatment should be considered in patients with an MS flare who are refractory to corticosteroid therapy?
Plasmapheresis
What medications are used as chronic maintenance therapy in patients with relapsing-remitting or secondary, progressive forms of MS
- Interferon beta or
- Glatiramer acetate
management of exertional heat stroke
- Rapid cooling: Ice water immersion preferred; can consider: high-flow cool water dousing, Ice/wet towel rotation, evaporative cooling
- Fluid resuscitation
- Electrolyte crrection
- Management of end-organ complications
- No role for antipyretic therapy
What cooling method is preferred for nonexertional or classic heat stroke (seen in elderly patients with underlying comorbidities that limit their ability to cope with excessive heat)
-Evaporative cooling as ice water immersion is associated with higher morbidity and mortality in these patients
In a patient with MS and risk factors for cholesterol plaques how do you differentiate an acute MS exacerbation from a TIA using time frame?
- Neurological deficits related to an acute demyelinating plaque of MS usually last for days to weeks
- Transients symptoms lasting <24 hours in a patient with multiple vascular risk factors are much more suggestive of TIA
When a patient presents for evaluation of a headache, it is important to assess for warning signs that should lead to the consideration of early imaging . . what are these warning signs?
-Neurologic findings: Seizures, changes in consciousness, specific deficits
-Differences compared to prior headaches: Change in frequency, intensity, characteristics
-Other: New at age >40, sudden onset, present on awakening
. . . Get MRI
The pathophysiology of Trigeminal neuralgia is thought to be related to what?
demyelination along the trigeminal nerve root (as it enters the pons), likely from localized compression (e.g. vascular structure)
Guillain-Barre syndrome is an acute or subacute ascending polyradiculoneuropathy that is often preceded by an upper respiratory tract infection or diarrheal illness. It typically presents as bilateral leg weakness that ascends to the arms, respiratory muscles, and face to generalized flaccid paralysis. Distal paresthesias are common, but other sensory symptoms are uncommon or mild. Reflexes are diminished or absent. Autonomic disturbances are common and include tachycardia, bradycardia, hypertension, orthostatic hypotension, and urinary retention. What does CSF usually show?
- High protein concentration
- normal white blood cell counts
- This is called ALBUMINOCYTOLOGIC DISSOCIATION)
- RBCs and glucose normal
Gold Standard treatment of Guillain-Barre
IVIG or plasmapheresis
eponym for frontotemporal dementia?
Pick disease
This is characterized b progressive bilaterally symmetic and predominantly high frequency sensorineural hearing loss that occurs over many years
Presbycusis (age-related hearing loss)
Presbycusis affects more than half of all adults by age 75 and is due to what?
degenerative changes of the inner ear or cochlear portion of the eighth cranial nerve
Otosclerosis is characterized by the development of sclerotic changes within the ossicles of the middle ear, resulting in what type of hearing loss and exam?
- Conductive
- normal otoscopic exam
serum methylmalonic acid levels in B12 deficiency
elevated
Gait dysfxn, Heachaches with nausea worse in mornings, and focal left-sided weakness raises concern for what
-intracranial tumor affecting the motor cortex
A patient with deterioration of neurologic status 2 days after an ischemic stroke most likely has had what?
a hemorrhagic transformation
next step in suspected hemorrhagic transformation
Emergent noncontrast CT scan of the head as surgical decompression is often needed
What is the most common cause of spontaneous lobar hemorrhage, particularly in adults age >60?
What Dz is this associated with?
cerebral amyloid angiopathy
-NOT with systemic amyloidoses, the amyloidogenic proteins are usually the same as those seen in Alzheimer dementia
What is the most common cause of intracranial hemorrhage in children
AV malformation
Describe the findings for a PROBABLE diagnosis of Creutzfeldt-Jakob disease
- Rapidly progressive dementia
- 2 out of 4 clinical features 1) Myoclonus 2) Akinetic mutism 3) Cerebellar or visual disturbance 4) Pyramidal/extrapyramidal dysfunction (hypokinesia)
- Periodic sharp wave complexes on EEG and/OR
- positive 14-3-3 CSF assay
Describe how to definitively diagnose Creutzfeldt-Jakob disease?
- Probably diagnoses in different slide in combination with
- Brain biopsy findings (gold standard) . . Spongiform changes OR
- Demonstrated PRNP gene mutations
Glucocorticoid-induced myopathy presents with proximal muscle weakness and atrophy without pain or tenderness; Lower extremity muscles are more involved . . what are the levels of ESR and CK
normal
CK levels in Statin induced myopathy and hypothyroid myopathy
high
This is usually seen in vasculitis and is caused by nerve damage in 2 or more nerves in separate parts of the body. Patients typically develop asymmetric peripheral nerve findings sich as wrist or foot drop
Mononeuritis multiplex
What lifestyle choice has the strongest association with both ischemic and hemorrhagic stroke?
Hypertension due to elevated shearing force on the intracerebral vascular endothelium, which accelerates the atherosclerotic process and promotes thrombi formation
Lacunar stroke of the posterolateral thalamus typically presents with sudden-onset contralateral sensory loss involving all sensory modalities (ie, pure sensory stroke). Weeks to months later, patients can develop What syndrome, characterized by severe paroxysmal burning pain over the affected area that is exacerbated by light touch (allodynia)
Thalamic pain syndrome
- Acute, peaks at 2 weeks
- Monocular vision loss
- Eye pain with movement
- “washed-out” color vision
- Afferent pupillary defect
Optic neuritis
Optic neuritis is strongly associated with what Disease
Multiple sclerosis
Suspect this in young obese female with a headache that is suggestive of a brain tumor, but with normal neuroimaging and elevated CSF pressure
Benign intracranial HTN (pseudotumor cerebri)
Presentation of right-sided hemiparesis, lower facial paresis, intact sensations suggests pure motor hemiparesis due to a stroke where?
Lacunar stroke in the posterior limb of the left internal capsule
Lacunar infarcts are most commonly associated with what modifiable health issue
-chronic HTN, which leads to arteriolar sclerosis and vessel occlusion (hypertensive vasculopathy)
Time frame for thrombolytics after ischemic stroke
< 3 - 4.5 hours
Heat stroke is defined by what?
-Core temp >104F and CNS dysfunction
What is the mechanism that would explain persistent epistaxis in a heat stroke patient?
-DIC is a possible complication of heat stroke leading to coagulopathic bleeding
What type of gait in muscular dystrophy
Waddling gait owing to weakness of the gluteal muscles
ABORTIVE migraine therapies?
- Triptans
- NSAIDS
- Acetaminophen
- Antiemetics (e.g. metoclopramide, prochlorperazine)
- Ergots (e.g. dihydroergotamine)
PREVENTATIVE migraine therapies?
- Topiramate
- Divalproex sodium
- Tricyclic antidepressants
- Beta Blockers (e.g. propranolol)
