Vestibular system

  • inner ear:

    • otolith organs in vestibulr detect vertical and nonrotational movement

    • ampullary receptor in semicircular canals detect rotation

      • on rotation: one side stimulated, other inhibited

  • Vestibulo-ocular reflex

    • quick visual movments in opposite direciton

  • vestiular nuclei

    • impulses to limb/trunk muscles to contract and preserve balance

Symptoms

  • Vertigo

    • sensation of movement

    • either body or environment

    • aymmetric dysfunction of vestibular system

  • Dizziness

    • sense of spatial disoreintation without false sense of motion

    • “light-headedness”

    • presyncope

    • usually has vardiovascular cause

    • accompanied by other symptoms

      • pale

      • slammy

  • Disequilibrium

    • off balance wihotu dizizness

      • especially when walking

    • floor tilted

    • can originate from inner ear or other sensory organs

    • bilateral dysfunction of vestibular system

    • causes:

      • ototoxic loss of vestibular system

      • head trauma

      • cerebrovascular disease

      • progressive loss of vestibular function due to age

      • spinocerebellar degeneration

      • osteoarthritis

      • multiple sclerosis

Cause

Duration

  • seconds: psychogenic

  • \<1min: BPPV

  • minutes - vascualr/ischaemic

  • Hours - Meniere’s disease or vestibular migraine

  • hours - days: vestibular neuritis

    • central causes possibel: stroke, vestiular migraine, MS

  • recurrent wiht headaches, photophobia, phonophobia: vestibular migraine

Trigger:

  • head position

  • recent head injury (even if trivial)

  • any new medicines (aspriin, phenytoin)

  • associated sympotms

    • tinnitus

    • hearing loss

    • aural fullness(pressure) in one ear

  • headache

Examination

red flags:

  • vertigo that continues for several days

  • Nystagmus down-beating and continuing

  • Unremitting headaches and nausea

  • Ataxia/cerebellar signs

  • Progressive hearing loss

  • Signs of suppurative labyrinthitis - bulging, erythematous tympanic membrane, fever, balance disturbance

  • cardiovascualr

  • BP: standing and supine (3min each)

    • ≥ 20mmHg decrease sbP = signifiant drop

  • Auscultation of neck (may raise suspicion of central lesion)???

  • otoscopy

    • deposits at top of ear drum

      • cholesteotoma compared to wax build up

  • Focused neurological examination

    • eyes

    • gait

    • balance

    • co-ordination

    • hearing

    • head impulse test

    • Dix Hallpike (who don’t have spontaneous nystagmus whilst upright

nystagmus

slow component to the symptomatic side and fast (VOR) towards opposite

direction = fast

vertical = underlying central lesion except torsional of BPPV

Management

Symptomatic

  • reassure/wait and see

  • Antiemetics

    • prochlorperazine

    • cyclizine

  • BDZ not recommeded

Central:

  • recurrent/persistent

  • gait/movmenet abnormal

  • constant nausea

  • poor peformance on tests of cerebellar function

    • dysdiadochokinesis

    • heel-toe walking

  • refer for imaging (MRI)

BPPV

  • life time prevalence = 2.4%

  • otoconia in vestibule become dislodged and eneter semicircular canals - post. canal

  • often associated to truama (especially young people)

  • Epley canalith repositioning procedure

    • sucess = 70%

    • 100% successive manoeuvres

    • when no resonse = suspect central cause

Meniere’s disease

  • several hours of vertigo associated with fluctuating

    • hearing

    • tinnitus

    • aural fullness

  • excess of cochlear endolymph

  • refluxes into semicircular canals

  • usually >40 but in 1/3 after 60

  • refer for further investigation and confirmation of diagnosis

  • based on classical symptoms + pure tone audiogram

  • MRI to exlude retrocochlear pathology

  • treatment = symptom control

    • betahistine

      • maximum = 48mg/day

      • signifiant benefit derived from doses more than this

    • lack of evidence for diuretics

Vestibular neuritis

  • singe, severe episdoes of vertigo lasting at least 48hrs = vestibular neuritis

  • abnormal head impulse test

    • unilateral vestibulopathy

  • horizontal nystagmus

  • if head impulse test normal - cerebellar infarction should be suspected

  • reactivution of herpes simplex in vestibular nerves

  • BPPV may develop in ear

Labyrinthitis

  • AOM + vertigo, balance and hearin gloss

    • viral/bacterial tru labyrinthitis = IV Abx required

Vestibular migraine

  • recurrnet fluctuating vertigo

  • treat as for migraine

  • many recreational drugs

    • EtOH