Neuro 1 Flashcards
Which arteries feed the pons?
Basilar artery (also midbrain) Anterior Inferior Cerebellar Artery (also parts of cerebellum)
What artery feeds the medulla?
Posterior Inferior Cerebellar Artery
What do the first-order neurons of the dorsal columns do? What do the second-order neurons do?
Enter at ipsilateral dorsal horn…ascend in fasciculus gracilis (lower body) and cuneatus (upper body)…synapse at nucleus gracilis and nucleus cuneatus…respectively
Decussate at medulla…ascend as medial lemniscus
What information do the nerves in the medial lemniscus carry?
Two-point discrimination*
Vibration
Proprioception*
What do the first-order neurons of the spinothalamic tract do? Second-order?
Originate in DRG, synapse in dorsolateral tract of Lissauer
Decussate in ventral white commissure…ascend in lateral spinothalamic tract
What information do the nerves in the lateral spinothalamic tract carry?
Pain
Temperature
What do the first-order neurons of the corticospinal tract do? Second-order?
Descend from internal capsule and midbrain…decussate in medullary pyramids…descend in corticospinal tract…synapse in ventral horn through interneurons
Exit through ventral horn
What information do nerves in the corticospinal tract carry?
Voluntary movement of striated muscle
A patient comes in presenting both lower motor involvement (weakness, cramps, fasciculations) and upper motor involvement (difficulty walking due to spasticity). What does this person likely have? What is affected?
Amyotrophic Lateral Sclerosis (ALS…AKA Lou Gehrig’s)
Cerebral cortex, brain stem, spinal cord (corticospinal tract, ventral horn)
A patient comes in after 2-5 days of flu-like symptoms with asymmetric weakness and flaccid paralysis. What is likely going on? What is affected?
Poliomyelitis (poliovirus is a picornavirus)…can still happen after ORAL vaccine
Ventral horn
A patient comes in with lightening-pain shooting down thigh or abdomen and has had difficulty walking. On exam, his eyes don’t react to light, but they do react to near test. What is the likely diagnosis? What is affected? What else could be going on with this patient?
Tabes dorsalis (tertiary syphilis)
Dorsal columns
Cardiac problems and/or gummatous syphilis (granulomatous infiltration of any organ [liver, skin])
A patient is brought in with bilateral flaccid paralysis and bilateral spastic paresis. On exam, it is determined that sense of pain and temp are also lost. What is likely diagnosis? What is affected?
Spinal artery syndrome
Corticospinal tract (at level of lesion) Spinothalamic tract (one level below lesion) Ventral horn (at level of lesion) Lateral gray matter (at level of lesion)
A patient comes in with bilateral spastic paresis affecting her legs. On exam, she is found to have decreased since of vibration and two-point discrimination. What would you likely see on labs? What is affected?
Megaloblastic anemia…because this is B12 deficiency
Dorsal columns
Corticospinal tracts
A patient is brought in with bilateral flaccid paralysis. On exam, he is found to have lost send of pain and temp bilaterally almost as high as he feels weak. What is the likely diagnosis? What is affected?
Syringomyelia
Ventral horn
Ventral white commissure…where spinothalamic tract decussates
A patient is found to have loss of vibration and discriminatory sense, spastic paresis, and flaccid paralysis on one side; and loss of sense of pain and temp on the other side. What is the likely diagnosis? What is affected?
Brown Sequard syndrome (I think this is like a stabbing victim)
ALL tracts on one side
A patient has a headache, neck pain, AMS, positive Brudzinski and Kernig signs, and petechiae. What is the likely bug?
Neisseria meningitidis
What should always be done before doing an LP? Why?
Neuro exam
Increased intracranial pressure + LP = increased risk of uncal herniation
Increased intracranial pressure: papilledema, focal neurologic deficits, pupil asymmetry)
How is meningitis initially treated?
Third gen cephalosporin (ceftriaxone)
What should be given to close contacts of patient’s with bacterial meningitis?
Rifampin or ciprofloxacin for Neisseria
Rifampin for H. influ in nonvaccinated kids
What viruses can cause meningitis?
Enterovirus Echovirus HSV Lymphocytic choriomeningitis virus Mumps virus
What is the most common cause of meningitis in newborns? What else can cause it?
GBS
E. coli, listeria, H. influ
What is the most common cause of meningitis in 1m-2yo? What else can cause it?
Strep pneumo and N meningitidis
GBS, Listeria, H. influ
What is the most common cause of meningitis in 2-18yo? What else can cause it?
N. meningitidis
Strep pneumo, Listeria
What is the most common cause of meningitis in 18-60yo? What else can cause it?
Strep pneumo
N. meningitidis, Listeria
What is the most common cause of meningitis in 60+yo? What else can cause it?
Strep pneumo
Listeria, gram- rods
An LP is done of a patient with expected meningitis, and results are: elevated WBC (lymphocytes), significantly elevated pressure, decreased glucose, and increased protein. What kind of meningitis is it? What should be given?
Fungal infection or TB
Fungal: Amphotericin B
TB: RIPE
What can cause encephalitis?
It is a viral infection
VZV, HSV, mumps virus, poliovirus, rhabdovirus (rabies), coxsackie virus, arbovirus (St. Louis and Cali strains), flavivirus (West Nile), and measles
A patient presents with severe pain kinda over cheeks and along the jaw. What should be considered? What is the treatment?
Trigeminal neuralgia
Carbamazepine, baclofen, phenytoin, gabapentin, valproate, clonazepam, or other anticonvulsants…surgical decompression of nerve may help
What are the most common causes of thrombotic strokes?
Atherosclerosis of carotid, basilar, or vertebral arteries
What is the most common cause of embolic stroke? Where does it most commonly occur?
Emboli originate in heart, aorta, carotid, or intracranial arteries
Middle cerebral artery
What distinguishes a TIA from a CVA?
Time…24hrs
Within what time frame should thrombolytic therapy be given for a stroke? (assuming no contraindications)
Within 3 hours of onset
When should heparin or LMWH be given?
For a progressive embolic stroke
How are hemorrhagic strokes treated?
Reversal of anticoagulation
Control BP
Control ICP (mannitol, hyperventilation, anesthesia)
Surgical decompression
Antiplatelets can be restarted after 2 weeks
A patient comes in with stroke like symptoms and a BP of 180/100. Should the BP be treated?
Not immediately…need to maintain cerebral perfusion
Would if >220/120 or if patient has CAD
What can all cause parenchymal hemorrhages?
HTN, AVM, brain aneurysm, or stimulant abuse
A person has a stroke of the ACA. What are the symptoms?
Contralateral lower extremity and trunk weakness
A person has a stroke of the MCA. What are the symptoms?
Contralateral face and upper extremity weakness and decreased sensation
Bilateral visual abnormalities
Aphasia (if dominant hemisphere)
Neglect
Inability to perform learned actions (if nondominant hemisphere)
A person has a stroke of the PCA. What are the symptoms?
Contralateral visual abnormalities
Blindness (if bilateral PCA involvement)
A person has a stroke of the lacunar arteries. What are the symptoms?
Focal motor or sensory deficits
Loss of coordination
Difficulty speaking
A person has a stroke of the basilar arteries. What are the symptoms?
Cranial nerve abnormalities Contralateral full body weakness and decreased sensation Vertigo Loss of coordination Difficulty speaking Visual abnormalities Coma
A non-contrast CT is done on a patient with the worst headache of his/her life, but it doesn’t show anything. What should be done? What might be seen?
Get an LP
RBCs
Xanthochromia (yellowness)
Increased pressure
What kind of hemorrhage causes an epidural hematoma? How is it treated?
Meningeal arteries (middle most common)
Emergent drainage…stabilization of ICP and BP
What are some ways that an epidural can be distinguished from a subdural hematoma?
Epidural can cross midline and is convex
Subdural cannot cross midline and follows curvature of the brain
What causes a subdural hemorrhage? How is it treated?
Rupture of bridging veins (trauma)
Surgical drainage or supportive…depends on size
What should be done if a subdural hemorrhage is expected? What should not be done?
Get a CT without contrast
Do NOT get an LP…increased risk of herniation
A patient is brought in and he isn’t saying much…and he is having a hard time coming up with words, but he can understand what you say. On exam he has face and arm hemiparesis and you notice he has a hard time chewing and drinking. What kind of aphasia is this? What is all injured?
Broca aphasia (expressive aphasia)
Inferior frontal gyrus
Dorsolateral frontal cortex
Anterior parietal cortex
A patient comes in and is pretty well talking gibberish and does NOT understand what you are saying. What kind of aphasia is this? What is all injured?
Wernicke aphasia (receptive aphasia)
Posterior superior temporal gyrus
Inferior parietal lobe
A patient comes in with fluid speech, but sometimes uses the wrong word and frequently attempts to correct words with word-finding pauses. What kind of aphasia is this? What is all injured?
Conduction aphasia
Supramarginal gyrus
Angular gyrus
A patient comes in speaking gibberish and cannot understand you; he also has limb ataxia. What kind of aphasia is this? What is all injured?
Global aphasia
Large infarcts of left cerebral hemisphere
A patient comes in with strange behavior, incontinence, and recent falls. What is likely going on? What would be seen on imaging? What is the treatment?
Normal pressure hydrocephalus (wacky, wet, and wobbly)
MRI: enlarged cerebral ventricles, white matter lesions, and aqueduct atrophy
Ventriculoperitoneal shunting
A patient is brought in because of brief periods of paresthesias, hallucinations, or repetitive/non-purposeful movements; but has NOT lost consciousness. What did this patient likely experience? What is involved? What would be seen on EEG?
Simple partial seizure
Focal cortical region of the brain
Distinct focal conductive abnormality
A patient is brought in because of episodes of hallucinations (auditory, visual, or olfactory), automatisms (repeated coordinated movements), or deja vu; patient has impaired consciousness and postictal confusion. What is going on? What is involved? What would be seen on EEG?
Complex partial seizure
Focal cortical region (most commonly temporal lobe)
Focal abnormalities in temporal lobe
A patient is brought in because of tonic, clonic, tonic-clonic, myoclonic (repetitive contractions), or atonic episodes; patient LOSES consciousness and has Todd paralysis (weakness that lasts hours). What is going on? What is involved? What would be seen on EEG?
Generalized convulsive seizure
Bilateral cerebral cortex
Generalized* electrical abnormalities
What is involved in an absence seizure? What is seen on EEG?
Bilateral cerebral cortex
Generalized three-cycle/second spike-and-wave pattern
Which antiepileptic drugs work by inhibiting voltage-gated sodium channels?
Carbamazepine Phenytoin Lamotrigine Oxcarbazepine Zonisamide
When is carbamazepine used? what are significant possible side effects?
Mono therapy for partial or generalized convulsive seizures
Hyponatremia, SJS, leukopenia
When is phenytoin used? what are significant possible side effects?
Mono therapy for partial or generalized convulsive seizures
Status epilepticus
Gingival hyperplasia, androgenic, lymphadenopathy, SJS
When is lamotrigine used? what are significant possible side effects?
Partial seizures
Second-line for for t-c seizures
Rash, SJS
When is oxcarbazepine used? what are significant possible side effects?
Mono therapy for partial or general convulsive seizures
Hyponatremia, rash
When is zonisamide used? what are significant possible side effects?
Second-line drug for partial or general convulsive seizures
Somnolence, confusion
How does ethosuximide work? When is it used?
Inhibition of neuronal calcium channels
Absence seizures
How do phenobarbital, benzodiazepines, and tiagabine work?
Enhance GABA activity
When is phenobarbital used? what are significant side effects?
Nonresponsive status epilepticus
General cognitive depression, rebound seizures
When are benzos (-zepam or -zolam) used? What are significant side effects?
Status epilepticus
Tolerance, rebound seizures
When is tiagabine used? What are significant side effects?
Second-line for partial seizures
Abdominal pain
What drug inhibits sodium channels and enhances GABA activity? When is it used? What are significant side effects?
Valproate
Mono therapy or second drug for partial and generalized seizures
Hepatotoxicity, weight gain, alopecia…teratogenic (spina bifida; abnormal face)
What antiepileptic inhibits NMDA-glutamate receptors and enhances GABA activity? When is it used? What are significant side effects?
Topiramate
Second-Ind drug for partial and generalized seizures
Wt. loss, cognitive impairment, heat intolerance, paresthesias
When is gabapentin used?
Mono therapy or second line drug for partial seizures
When is levetiracetam used?
Mono therapy for partial seizures
second-line for partial or generalized seizures
What causes status epilepticus?
Withdrawal of anticonvulsants Alcohol withdrawal Trauma Preexisting seizure disorder Metabolic abnormalities
