Neuro exam 1 Flashcards
(143 cards)
Physiological mechanism of migraine
trigger event -> cortical spreading depression:
trigeminal nerve -> vasodilation and pain OR
inferior subcortex -> no aura OR
surface cortex -> aura
Blood vessel abnormalities are a component of vascular headaches such as ________ and ________ headaches
migraine
cluster
______ play a critical role in vascular headaches involving nerves
5-HT
What does a low 5-HT level cause
migraine, it reduces urinary and platelet 5-HT w/ elevations in 5-hydroxyindole acetic acid during mirgraine
Where are the 5-HT1B receptors located
endothelium of the micro vessels and mediate vasodilatory and contractile effects
How does 5-HT receptors act in the meninges
block the release of inflammatory chemical
How does 5-HT receptors act in the brainstem
block the pain impulses and central brain perception via trigeminal nerve
Sumatriptan (5-HT1B receptor agonist) MOA
inhibits the release of calcitonin gene-related peptide (CGRP) which acts in the superior sagittal sinus following stimulation of trigeminal ganglion
What are the 5-HT1B/1D agonists
Triptans
sumatriptan, zolmitriptan, naratriptan, rizatriptan
produce vasoconstriction
not for prophylatic treatment
5-HT2 receptor antagonists
methysergide
used for prophylatic measure
ADE of triptans
cardiac effects (vasospasm, myocardial ischemia, arrhythmias in pt with coronary artery disease)
pain at inj site
paresthesia, asthenia, fatigue, flushing, pressure in chest, neck, jaw, drowsiness, dizziness
Triptans contrindications
pt with coronary artery disease, ischemia, or cerebrovascular disease
pt taking MAO-I
How does ergotamine and caffeine help migraines
ergotamine: block NE reuptake and stimulates adrenergic receptors, activates serotonin pathways, reduces intracranial blood flow
caffeine: adenosine receptor antagonist
Reyvow (lasmiditan) use in migraines
acute tx w/ or w/out aura not preventative
Reyvow (lasmiditan) MOA
bind to 5-HT1F receptors, mediated by agonist effects at the receptor
Reyvow (lasmiditan) ADE
dizziness, fatigue, burning or prickling sensation in the skin, sedation
serotonin syndrome
Increased comorbidity with migraine
stroke, epilepsy, depression, sleep apnea, obesity, anxiety, pain disorders
Pathophysiology of migraine headaches
vasodilation of intracranial extracerebral blood vessels -> activation of perivascular trigeminal nerves that release vasoactive neuropeptides
CGRP, neurokinin A, substance P
Vasoactive neuropeptides promote ________ _________ around vascular structures in the brain -> pain
neurogenic inflammation
Associated symptoms of central pain transmission that activate other brainstem nuclei
nausea, vomiting, photophobia, phonophobia
Medications that can precipitate a migraine headache
antibiotics (tetracyclines, SMZ,TMP)
NSAIDs
bronchodilators (theophylline, pse)
GI (cimetidine, omeprazole)
CV (vasodilators, nitrates, dipyridamole)
Reproductive (estrogen)
Clinical Presentation of migraine headache
common, recurrent, severe headache that interferes w/ normal functioning
What is aura
complex of positive and negative focal neurologic symptoms that proceed or accompany an attack
evolves over 5 min and lasts less than 60 minutes
headache occurs w/in 60 min of the end of the aura
Positive visual auras
scintillations (flash of light)
photopsia (perceived flashes of light)
teichopsia (transient sensation of bright shimmering colors)
fortification spectrum (zigzag banding of light)