15. Dizziness and Vertigo Flashcards
Acute vestibular syndrome defn
dizziness acute, constant, persists >day, accompanied by n/v, unsteady gait, nystagmus and interolance to head motion
What 3 systems are key for equilibrium and awareness of body in relationship to surrounding sx
visual
proprioceptive
vestibular systems
What does the vestibular apparatus do?
maintain head position
stabilize head movement
What is the vestibular apparatus made up of?
three semicircular canals and two otholithic structures
Semicircular canal info
info about movement and angular momentum
Utricle info
head tilt and vertical linear accel
How to otoliths move in BPPV
freely moving otoliths that are inappropriately located within the semicir- cular canals, as in BPPV, can produce positional vertigo even when the head is currently still if the head had been recently moved.
impulse travel from vestibular apparatus to brainstem and cerebellum
acoustic nerve (cranial nerve [CN] VIII), enter the brainstem just below the pons and anterior to the cerebellum, and proceed to the four vestibular nuclei of the brainstem and to the cerebellum
From brainstem and cerebellum, impulses travel along which 2 pathways to cause vertigo?
1) MLF
2) vestibulospinal tract
When does nystagmus occur?
when syncronhized vestibular info becomes unbalanced
Typically, it results from unilateral vestibular dis- ease, which causes asymmetric stimulation of the medial and lateral rectus muscles of the eye. This unopposed activity causes a slow move- ment of the eyes toward the side of the stimulus, regardless of the direc- tion of deviation of the eyes. The cerebral cortex then corrects for these eye movements and rapidly brings the eyes back to the midline, only to have the process repeated.
By convention, the direction of nystagmus is denoted by the direction of the ?“cortical” component.
fast
Vertebrobasilar insufficiency defn
emporary set of symptoms due to ischemia in the posterior circulation of the brain, which supplies the medulla, pons, midbrain, and cerebellum. M
BPPV pathophysiology
Otoliths inappropriately displaced from utricle into semicircular canals (posterior > horizontal > anterior)
Vestibular neuritis and labrynthitis pathophys
inflamm/possibly viral of vestibular nerve
Meniere disease pathophys
endolymphatic hydrops/excess endolymph in inne ear
Perilymph fistula pathophys
abnormal opening btwn middle and inner ear
DDX peripheral vertigo
bppv
vestibular neuritis and labrynthitis
meniere disease
perilymph fistula
DDX of dizziness into 3 categories - what are they?
acute severe - vestibular neuritis, stroke
recurrent attacks: Meiniere, tia
recurrent positional: bppv, cerebellar tumor, ms
ddx timing and triggers approach 3 categories -defn
- ac vestibular: bestibular neuritis, cerebellar stroke
- spont episodic vestibular syndrome - meniere disease, vbi
- triggered episodic vestibular syndrome - bppv
vertigo defn
spining sens
triad meniere disease
hearing loss
vertigo
tinnitus
Peripheral causes of vertigo - list 8
Benign paroxysmal positional vertigo (BPPV) Vestibular neuritis (or neuronitis)/labyrinthitis Ménière disease
Foreign body in ear canal
Acute otitis media Perilymphatic fistula
Trauma (labyrinth concussion) Motion sickness
Acoustic neuroma
central causes of vertigo
Vertebral basilar artery insufficiency Cerebellar hemorrhage or infarction Tumor
Migrainous vertigo
Multiple sclerosis
Posttraumatic injury (temporal bone fracture, postconcussive syndrome) Infection (encephalitis, meningitis, brain abscess)
Temporal lobe epilepsy
Subclavian steal syndrome
BPPV hx
Short-lived (typically <30 s), positional, fatigable episodes; more often in older adults.
Name 5 medications causing vestibulotoxicity
(e.g., aminogly- cosides, anticonvulsants, alcohols, quinine, quinidine, and minocy- cline
Subclavian steal syndrome PE
When subclavian steal syndrome is suspected, which also can cause VBI, the pulse and blood pressure should be checked in both extremities. A difference in blood pressure of greater than 40 mm Hg from one arm to the other is concerning for subclavian steal syndrome, and the patient will likely have arm fatigue or other symptoms on the affected side.
Vesibular neuritis/labrynthitis hx
Vertigo may develop suddenly or evolve over several hours, usually increasing in intensity for hours, then gradually subsiding over several days but can last weeks. Can be worsened with positional change. Sometimes history of viral infection precedes initial attack. Highest incidence is found in third and fifth decades.
What is Wallenberg syndrome?
occlusion of PICA: vertigo associated with significant neuro complaints
n/v, loss of pain and temp sensation on side face ipsi to lesion and opp side obdy
parlysis palate, pharynx, larynx
Horner syndrome (ipsi ptosis, miosis, decr facial sweat)
Peripheral vs central vertigo: onset
sudden
gradual
Peripheral vs central vertigo: intensity
severe initial, then decr over time
mild in most bu can be sev in stroke and ms
Peripheral vs central vertigo: duration
intermittent episodes lasting seconds to less than min for bppv/cont long for vestibular neuritis
wk, months cont but can s-mins with vascular causes such as with posterior circulation tia
Peripheral vs central vertigo: direction of nystagmus
torsional, upbeat in classic posterior canal bppv or horiz bppv/vestibular neuritis/labrynthitis
vertical, spont and torsional, direction changing on lat gaze, downbeating
Peripheral vs central vertigo: effect of head pos
induces vertigo (bppv), worsens vertigo )vestibular neuritis)
little change but can worsen with position cange
Peripheral vs central vertigo: assoc neuro findings
none
usually present
Peripheral vs central vertigo: assoc auditory findings
present possible, including tinnitus 9meniere) and hearing loss (labrynthitis)
rare
Internuclear opthalmoplegia defn
indi- cates brainstem pathology, is recognized when the eyes are in a normal position on straight-ahead gaze, but on eye movement the adducting eye (CN III) is weak or shows no movement while the abducting eye (CN VI) moves normally (although often displaying a coarse nystag- mus).
This finding indicates an interruption of the MLF on the side that demonstrates third CN weakness and is virtually pathognomonic of multiple sclerosis.
Cerebellar tests
dysmetric finger to nose
dysdiadochokinesia -rapid alternating movements
ataxic gait
nystagmus
How to test midline cerebellum lesions?
truncal ataxia sit to stand to walk unaided
Dix Hallpike test
only for bppv/triggered
turns the patient’s head 45 degrees to one side and then moves the patient from the upright seated position to a supine position with the head overhanging the edge of the gurney (Fig. 15.1). The patient is que- ried for the occurrence of vertigo, and the eyes are observed for nys- tagmus after a latency period of a few seconds. In a patient with classic posterior canal BPPV, the nystagmus usually lasts 5 to 30 seconds and is combined upbeating (the fast phase beats toward the forehead) and ipsilateral torsional (the top pole beating toward the downward ear). The patient is then brought back up to the seated position, and the test is repeated with the head turned 45 degrees to the other side
Classic findings during dx hallpike test in posterior canal bppv
Latency (delay in nystagmus and vertigo once in head-hanging position) of approximately 3–10 s, although delay can take up to 30 s on rare occasions
Reproduction of vertigo symptoms in head-hanging position
Upbeat (fast phase toward forehead) and torsional nystagmus (usually toward
the downward ear)
Vertigo and nystagmus escalate in head-hanging position, then slowly resolve over 5–30 s
Nystagmus and vertigo may reverse direction when patient returns to sitting position
Nystagmus and vertigo decrease with repeated testing (fatigability)
If dix hallpike +, epley menuever - how to perform?
The first step of the Epley maneuver is the first part of the Hallpike test, which involves turning the head 45 degrees to the involved side and then laying the patient with the head hanging over the edge of the gurney.)
HINTS exam - what does this entail?
HINTS (Head Impulse test, Nystagmus, Test of Skew) is a bedside oculomotor examination test that has been proposed as a way to differentiate central from peripheral vertigo in patients with acute vestibular syndrome.
- head impulse test
nystagmus
test of skew
What is the head impulse test
corrective saccade indicates a positive test and is more reas- suring for vestibular neuritis, which is a benign cause of vertigo.
Nystagmus: of hints test - peripheral vs central
non horizontal = concern central (changing, vertical, torsional)
Test of skew findings
The third part (test of skew) refers to vertical ocular misalignment during alternate cover testing, and its presence is suggestive of brainstem strokes.
BPPV vs vestibular neuritis/labrynthitis: age
older
yo
BPPV vs vestibular neuritis/labrynthitis: hearing loss
none
none in vestib neur/hearing loss
BPPV vs vestibular neuritis/labrynthitis: freq sx
episodic
constant
BPPV vs vestibular neuritis/labrynthitis: hallpike test
+
worse in head hang but really shouldn’t do
BPPV vs vestibular neuritis/labrynthitis: head impulse test
neg
+
BPPV vs vestibular neuritis/labrynthitis: epley
highly effective
ineff
BPPV vs vestibular neuritis/labrynthitis: recurrence
freq
rare
Barbeque roll tx for BPPV
horizontal canal variant of BPPV
patient lies flat on the gurney with the head turned 90 degrees to the involved side. The head is then rotated in 45-degree intervals away from the involved side (each turn is held approximately 30 seconds or until nystagmus and vertigo resolve). Eventually the patient needs to turn over into the prone position
Vestibular neuritis inflamm of which nerve?
CN8
A patient presents to the emergency department with dizziness and is diagnosed with horizontal canal benign paroxysmal posi- tional vertigo (BPPV). What maneuver can be used to treat the patient?
a. Barbecueroll
b. Epley maneuver c. Hallpiketest
d. Head impulse test
a
b- epley tx posterior
A 70-year-old woman presents with a first ever episode of severe ver- tigo. Which of the following examination findings should prompt the physician to order imaging tests and/or consultation with a neurolo- gist?
a. Direction changing nystagmus on change in head position b. Direction changing nystagmus on change in lateral gaze
c. Positive head impulse test
d. Torsional upbeat nystagmus during Hallpike test
b
Internuclear ophthalmoplegia most often suggests a diagnosis of
which of the following conditions?
a. Horizontal canal benign paroxysmal positional vertigo (BPPV) b. Labyrinthitis
c. Multiplesclerosis
d. Vestibular neuritis
c
Which of the following is a central cause of vertigo? a. Labyrinthitis
b. Ménière disease
c. Vertebrobasilarinsufficiency
d. Vestibular neuritis
c
Continuous vertigo of what duration is used to define acute vestib-
ular syndrome? a. 1hour
b. 8 hours
c. 24hours
d. 1 week
c
First steps of management algorithm for dizziness and vertigo:
medical cause w/u: ecg, glucose, hbg, bun/cr, review meds
vs persistent sx - HINTS/focal neuro finding/can’t sit or walk
vs triggered: hallpike/supine roll/orthost vitals
vs spont sx: assess for tia vs vestibular migraine vs meniere disease
assess for tia vs vestibular migraine vs meniere disease - what are RF?
age
previous stroke
abn gait
focal neuro findings
complaint instability
hx vascualr disease
Name 5 meds you can give in acute vertigo
ondans
dimenhydrainate
metovlopromide
scopolamine
diazepam
