Bppv & vertigo

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Benign Paroxysmal Positional Vertigo

Most common - labyrinthine dysfunction abnormal sensation of motion that is elicited by

certain critical provocative positions Provocative positions

Head turn to affected side - getting out of bed Extend head back to look up “Top shelf vertigo”

Causes Idiopathic – 50% Head trauma, middle ear infection, viral

labyrinthitis, ear surgery

Pathophysiology

Otoliths (calcium carbonate particles) -normally attached to a membrane in utricle & saccule

Utricle is connected to semicircular canal

Two theories Canalolithiasis Cupulolithiasis

Canalolithiasis Otoliths displaced from utricle -

enter the posterior semicircular duct (most dependent SCC )

Changing head position relative to gravity causes the free otoliths to gravitate through the canal.

The concurrent flow of endolymph stimulates the hair cells of the affected semicircular canal causing vertigo.

Cupulolithiasis Otoconia attached

to cupula of scc Change in head

position result in displacement of cupula results in vertigo.

Sixth decade F>M Clinical features

Sudden onset rotatory vertigo Few secs Triggered by provocative movements No other aural symptoms

Dix-Hallpike maneuvre

Pt seats on the table Pt’s head held, turned

45 deg to Rt & pt placed at supine position – head hangs 30 deg below horizontal

Pt’s eyes observed for nystagmus

Test repeated on Lt side

Comparision of positional nystagmus of BPPV with lesions of the CNS

BPPV CNSLatent period

A few seconds nil

Distress Present nil

Direction of nystagmus

Direction fixed – towards the undermost ear

Direction changing

Duration of nystagmus

Less than 30 sec Persists while position maintained

Fatiguablity

Nystagmus stop with repeated testing

Nystagmus persists with repeated testing

Epley’s manoeuvre for left posterior semicircular canal BPPV

(S) Start: patient is seated (1) Place head over end of table, 45 degrees to left. (2) Keeping head tilted downward, rotate to 45

degrees right. (3) Rotate head and body until facing downward

135 degrees from supine. (4) Keeping head turned right, bring patient to

sitting position. (5) Turn head forward, chin down 20 degrees. Pause at each position until nystagmus approaches

termination

Instructions following Epley’s maneuvre

Rest 10 min Sleep in semi-

recumbent For at least 1 week

Use two pillows Avoid bad side No head turning

far up or down

Surgical mangement

Posterior canal wall plugging debris can no longer

move within the canal Singular nerve

section Section the nerve that

transmits information from the posterior semicircular canal ampulla toward the brain.

Differential diagnosis of Vertigo

“Subjective sense of imbalance”

History Rotatory ? Onset (1st episode) Duration Progression Severity Episodic ?

Aggravating or relieving factors

Associated auditory/neurological symptoms

h/o chronic ear ds, trauma, surgery, intake of drugs

Rotatory Episodic

Seconds Hours

Prolonged Weeks

Unsteadiness Episodic

Seconds Hours to days

Prolonged Weeks to months

Rotatory vertigo

BPPV Labyrinthine

fistula Perilymphatic

fistula Caloric effect Cervical vertigo

Meniere’s disease Delayed

endolymphatic hydrops

Following middle ear surgery

Episodic - Few seconds Episodic - Few min to 24 hours

Vestibular neuronitis Acute labyrinthitis Trauma

Head injury Labyrinthectomy Vestibular neurectomy

Secondaries in CP angle

Prolonged - Days to weeks

Unsteadiness

Rapid movements Drugs Tranquilisers,

anticonvulsants Travel sickness hyperventilation

Episodic - seconds Episodic – hours to days

Late stage of vestibular neuritis, acute labyrinthitis

Elderly patients Drugs

Anticonvulsants, Gentamicin Vestibular schwannoma Functional

Prolonged – weeks to months

Examination ENT

Nystagmus Involuntary, rhythmical, oscillatory movement of

eyes Slow / fast component – direction of the nystagmus Procedure

Examiner keeps finger about 30 cm from the patients eyes in the central position & moves it right or left

Do not exceed 30 degree from the centre Enhanced with Frenzel glasses or in darkness

( optic fixation is lost)

Otoscopic examination & Tuning fork test Fistula test

Induce nystagmus - pressure changes in the external ear which are then transmitted to labyrinth

pressure induced by Intermittent pressure over the tragus Siegel’s pneumatic speculum

Fistula test negative – normal Fistula test positive

Labyrinthine fistula Perilymph fistula Post stapedectomy fistula

False negative fistula test Cholesteatoma covering the fistula

False positive fistula test ( positive fistula test in absence of fistula)

Meniere’s disease ( Hennebert’s sign)

Cranial nerves Cerebellar function

Gait Romberg’s test

Dysmetria Dysdiadokokinesia

Management

Investigations Audiomety Caloric test

Induce nystagmus by thermal stimulation of vestibular system Bithermal caloric test

Supine, head tilted forward 30 deg Ears irrigated with water

40 sec Alternately with water at 30 & 44 deg C

Time taken from irrigation to end of nystagmus charted on calorigram

Cold water – nystagmus to opposite side Warm water – nystagmus to same side (COWS) Depending upon the response to caloric test

Canal paresis – depressed function of ipsilateral labyrinth, vestibular nerve, vestibular nuclei

Directional preponderance – peripheral and central lesion

Electronystagmography Method of detecting & recording nystagmus

Rotational chair test Computerized dynamic posturography

Treatment Suppress vestibular symptoms Wait for vestibular compensation Treat the underlying cause

Medical Surgical