14. Vertigo Flashcards
What is the caloric reflex test?
Cold water: endolymph sinks in horizontal canal –> patient feels head turning to opposite side –> Eyes turn towards ipsi ear with CONTRA NYSTAGMUS
Hot water: endolymph rises –> patient feels head is turning to SAME side –> eyes turn CONTRA ear with IPSI nystagmus
What is the number one complaint of persons over the age of 70
dizziness
What is BPPV?
benign paroxysmal positional vertigo –> otoliths break off membrane and become lodged elsewhere –> false signals
What is the leading cause of accidental deaths in persons +65
Falls
Does have a reported fear of falling increase, decrease, or no change in the correlation with predicting a future fall
Fear of falling –> inc change of falling
Having how many risk of falling indicators are necessary to have a 100% chance of falling?
3 or more
What are the three reflexes associated with equilibrium?
Vestibuloocular (VOR)
Vestibulospinal
Vestibulocolic
Which semilunar canal is important in BPPV? Which is important in caloric testing?
BPPV: posterior semilunar canal
Caloric testing: horizontal semilunar canal
Which direction does nystagmus occur in BPPV?
Initially torsional (rotary) –> vertical
VOR does what
Gaze stabilization
VSR
Uses visual, proprioceptive information to coordinate balance and movement
Can still balance with 2/3 systems with training
CANNOT BALANCE WITH 1/3 SYSTEMS
VCR
Postural control. Acts on muscles in neck to stabilize the head
Uses utricle and saccule
Differentiate what happens with symmetric vs assymetric impulses
Symmetric = normal Assymetric = interpreted as vertigo
What is the vestibular clamp?
Inhibitory signal sent by cerebellum to vestibular nucleus when it sends assymetric impulses, but these are not strong
What artery supplies blood to the labyrinth and cochlea
AICA
When is the labyrinth formed during gestation?
47th day of gestation
Is nystagmus present with vertigo or dizziness?
Vertigo. Dizziness is any disturbed sense of relationship to space whereas vertigo is a sensation of the person spinning
Central vs peripheral vertigo
Peripheral vertigo is more severe, concerns the labyrinth or vestibular nuc
Central is generally associated with neurologic symptoms (diplopia, weakness, numbness, incoordination)
Meniere’s Disease - what is it?
Idiopathic distention of membranous labyrinth and cochlear duct
Meniere’s Disease triad
Hearing loss
Tinnitus
Vertigo
What is an important etiologic basis for meniere’s disease?
food sensitivity»_space; food allergy
How do you dx Meniere’s disease?
MRI
Tx for Meniere’s disease?
Benzodiazepines - VALIUM
What is something very important that you need to be concerned about when prescribing streptomycin IM?
It’s ototoxic; must be stopped to prevent hearing loss
What is something very important that you need to be concerned about when prescribing garamycin?
Can cause chemical labrynthectomy
What is acute labyrinthitis?
Inflammatory process occurring within labyrinth w/ bacterial or viral etiology
Bacterial mediated acute labyrinthitis
Children: Acute otitis media; must give abx
Adults: serous form occurs with bacterial toxins
Virus mediated acute labyrinthitis, tx
Seen during summertime
Severe vertigo, cochlear dysfunction
Tx: IV valium (must reduce it)
