FINAL neuro Flashcards
(165 cards)
What is CN IV (name, sensory vs. motor function)
Trochlear, motor
Function of CN IV
Superior oblique muscle of the eye
How is CN IV tested?
With CNIII- tracking moving objects
What is CN V (name, sensory vs. motor function)
Trigeminal, both sensory and motor
Function of CN V
Sensory signals from face (mouth, nose, eye, dura mater)
Motor fibers to the muscles of mastication
Name and briefly describe a condition causing dysfunction of CN V
Trigeminal neuralgia- hypersensitivity to pain in the areas innervated by CN V (ipsilateral face- eye, maxilla, mandible) caused by neurovascular or other compression or demyelination of CN V.
Herpes zoster opthalmicus- shingles in the opthalmic branch of trigeminal nerve
What is CN VI (name, sensory vs motor function)
Abducens, motor
Function of CN VI
motor- innervates lateral rectus of the eye
Dysfunction of CN VI causes?
Inability to ABDduct eye
Name all 12 cranial nerves
OOOTTAFVGVAH
olfactory, optic, oculomotor, trochlea, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, accessory, hypoglossal
What is myasthenia gravis?
A chronic autoimmune disease affecting the neuromuscular junction characterized by weakness of voluntary muscles
Describe the epidemiology of myasthenia gravis
2 peaks- women in 20-30s, men in 60-60s.
Risk factors: frequently manifests for first time in pregnancy, exposure to anesthetic agents, thymic hyperplasia/ tumor, other autoimmune disorders
Time course of myasthenia gravis
insidious onset, relapse and remissions with gradual progression of disease.
What muscles are usually affected first in myasthenia graviS?
mouth, eyes, face, mouth, throat, neck
Classic triad: ptosis, diplopia, dysphagia
Describe patho of myasthenia gravis
Chronic autoimmune disorder: antibody mediated attack on acetylcholine receptors (the nicotinic receptor) at the post synaptic membrane of the neuromuscular junction. Decreased in these receptors= diminished transmission of nerve impulses across neuromuscular junction.
type 2 hypersensitivity reaction
T-cell mediated
Symptoms of myasthenia gravis
Classic triad: ptosis, diplopia, dysphagia
-difficulty chewing, drooling, slurred speech, easily fatigable, symptoms more pronounced with fatigue or in the evening
-normal sensory perception, pupillary response, coordination
-eye movement dysfunction, cannot sustain arm raise, change in voice when counting to 100
What is myasthenic crisis
Life threatening, risk of respiratory arrest, triggered when resp muscles weakened to the point of needing a ventilatory. Often triggered by infection, fever, adverse reaction to med.
Treatment myasthenia gravis
Cholinesterase inhibitors (stop breakdown of Ach, therefore increasing concentration in neuromuscular junction) *can result in cholinergic crisis that mimics myasthenic crisis, but problem is too much Ach instead of not enough (diarrhea, cramping, bradycardia, pupils constrict, increased salivation, risk for resp arrest)
What NT is involved in myasthenia gravis
Acetylcholine (the receptors (nicotinic receptors) in post synaptic side of the neuromuscular junction are destroyed :(
What is restless leg syndrome?
Neuro disorder characterized by unpleasant sensation in legs accompanied by urge to move legs, esp at bedtime
Risk factors restless leg
DM, ESRD, anemia, iron deficiency anemia, MS, PD, pregnancy, venous insufficiency
Time course restless leg
Worse at evening/ night time/ with rest, preventing sleep
Patho restless leg
Cause unknown- believed to involve genetic component, dysfunctional dopaminergic transmission, and low brain iron stores
Signs and symptoms restless leg syndrome
-Occur when the limbs are at rest and are relieved by movement
-Symptoms may extend to arms and trunk
-Commonly bilateral and symmetrical, but can be unilateral on occasion
-Sensation described as burning, nagging, aching, painful, itching bones, electric current, creepy crawl