acute cases of vertigo Flashcards
define dizziness *
an illusion of self- and/or env motion
define vertigo *
illusory selfmotion which is spinning in nature
sibset of dizzyness
define oscillopsia *
visual world motion - because you lose the vestibulo-ocular reflex, so world wobbles when move head, becasue eyes dont move and stabalise the image
recogise how oscillopsia differs from vertigo *
vertigo is present even with one’s eyes shut
describe the vestibulo-ocular reflex *
stabalise the gaze in space - latency of 5-10ms
semicircular canals detect angular accelaration
accelorometer detect linear accelaration an tilt
when make a saccade movement - brain knows where you are moving to so the vision is suppressed = dont see world move
define nystagmus *
seeing the world move
what is evidence that the brain controls dizzyness et c
when stimultated :
low current = feeling of gentle rocking of self
high current - feeling of violent spinning of self and room
what are the causes of emergancy room vertigo
BPPV
vestiblar neuritis caused by bell’s palsy = vertigo, nystagmis, clumsiness - self limitng over a week
migrainous vertigo
stroke
mixed (syncope, anxiety)
meniere’s
what do you have to rule out when you see acute vertigo
presyncope
pul emb
cardiac dysrhythmia
what are the core eye examinations for acute vertigo *
cover
gaze
vestibulo-ocular reflex
hallpike
fundoscopy
describe fundoscopy
look at retina - check position of the disc and macula
is it spontaneousnystagmus
what is the effect of visual fixation on nystagmus
what are the core examinations for ears *
otoscopy
what are the core examinations for legs *
gait
tandem
describe the ear examination
hearing in complaint
otoscopy - only really useful with herpes - see vesicles
how can herpes cause dizzyness
infection go through temporal bone ad damage the vestibular nerve
treatment of posterior canal BPPV
epley manouver - allow fre floating particles of affected canal back to utricle so they dont stimulate the capula
semont - repositions the canaliths
what does BPPV stand for *
benign paroxysmal positional vertigo
what is the diagosis for BPPV
hallpike manoever - turn head 45 degrees, then lie back on bed quickly - head hangling slightly off- this makes crystals in SCC canals move = feeling of vertigo
describe the symptoms of vestiubular neuritis *
subacute onset - minutes-hours
continuous vertigo
obvious vestbular nystagmus
positiv ehead impulse test
normal gait
treatment of vestibular neuritis *
vestibular sedatives for 24-36hrs
mobilise at day 2-3
treat any BPPV pr migraine
what are red flags *
headache
gait ataxia - may be only non-vertiginous manifestation of cerebellar stroke
hyperacute onset - suggests vasscular origin
vertigo and hearing loss - anterior inferior cerebral artery or urgent ENT problem
prolongued symptoms >4days - floor off 4th ventricle problem
acute vestibuloar migraine signs
history of migraine
can have acute vertigo w/o prominant headache
recurrent
what is assessed in a leg examination *
gait - narrow based
tandem walking - count how many mistakes oput of 10 tandem steps
romberg - see if eye closure effects balance, can they maintain balance >20s w/o vision
what are the signs of bppv *
positional - ie lying back in bed because couldnt be postural hypertension
brief - seconds
signs of cerebellar stroke *
thunderclap onset vertigo - embolic because of valsalva, afib or dissection (when neck pain/trauma)
poor balance, unable to walk or sit
headache
red flags - gait problems, hearing loss, prologued symptoms
causes of positional nystagmus
either BPPV or central
what is latency of nystagmus *
time for onset
what is fatiguability of nystagmus *
lessening of the response with repition of the manouver
what happens to the threshold for vestibular motion in people with acute traumatic brain injuries in comparison to controls
larger range, generally much higher
how can the aTBI increase the thresold for vertigo
networks in the brain that are involved in vertigo are damaged
