BPPV Handout
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Transcript of BPPV Handout
8/10/2019 BPPV Handout
http://slidepdf.com/reader/full/bppv-handout 1/19
8/10/2019 BPPV Handout
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Incidence/Prevalence of BPPV
• Most common referred diagnosis in tertiarycenters
• 9% of randomly selected community
dwelling elderly (Oghalai, J.S. et al 2000)• Incidence increases 38% with each decade
of life (Froehling 1991)
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BPPV Basics
• BPPV most commonly affects theposterior semicircular canal.
• Observing nystagmus with Frenzel
lenses greatly assists in theidentification of involved canal(s)
• Supine head turns should be performedto check for lateral canal BPPV whenDix-Hallpike is negative.
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Extraocular Muscles
Lateral Rectus
(abduction)
Medial Rectus
(adduction)
Horizontal
Canal
Inferior Oblique(elevation, out-
torsion)
Superior Rectus
(elevation, in-
torsion)
AnteriorCanal
Inferior Rectus
(depression,
some out-torsion)
Superior Oblique
(depression, in-torsion)
PosteriorCanal
ContralateralIpsilateralCanal
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Nystagmus during CRP
• Nystagmus should remainipsidirectional during the procedure (i.e.if initial Dix-Hallpike positioning
provoked a right torsional nystagmus, itshould continue to be right torsionalthroughout the procedure)
• Reversal of nystagmus directionsuggests the particle has fallen backinto the canal and predicts failure.
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Evidence Based Outcomes
• Controlled randomized and blinded studiesusing Dix-Hallpike as outcome consistentlydemonstrate 72% efficacy with a singlemaneuver (White et al, O&N 2004, meta
analysis of 9 studies and over 500 patients).
• Spontaneous resolution in contrast is only31% at 3 weeks.
• Canalith repositioning is “highly effective”based on number needed to treat, relativerisk reduction.
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Lateral Semicircular CanalLSC-BPPV• Short latency horizontal nystagmus provoked
by supine bilateral head turns, with prolongedduration and poor fatigability.
• Uncommon (2-15% of total BPPV)
• Two forms
– Geotropic – beating towards undermost ear inright and left supine head positions
– Apogeotropic – beating away from undermost earin right and left supine head turn positions
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8/10/2019 BPPV Handout
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Apogeotropic LSC- BPPV
• The affected side is usually moredifficult to identify – The side to which spontaneous nystagmus
beats if it is present (rarely observed)
– The side to which nystagmus is lessintense during positioning
– The side to which nystagmus beats when
the patient goes from sitting to supine(rarely observed)
Vannucchi, Asprella and Gufoni, 2005
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Repositioning Maneuvers forApogeotropic LSC- BPPV
• Rapid supine head turn towards thegood side may mobilize debris in theproximal canal, converting nystagmus to
geotropic form (Asprella technique) andallowing repositioning
• Inverted Gufoni maneuver
– Patient lies quickly onto affected side andturns nose up for two minutes
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Treating Posterior to Lateralcanal conversion
• Canal conversion confirms a mobileparticle
• Conversion involves the ear just treatedso the side of lateral canal involvementis certain
• Any of the lateral canal techniques will
work (Lempert, Vanucchi-Asprella)remember to rotate the head towardsthe good ear. 180 degrees will work ifutilized immediately.
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Anterior Canal BPPV
• A rare and poorly understood type of BPPV
• May have a strong paroxysmal downbeatnystagmus in head hanging as the mainfinding (r/o 75% with central etiology)(Bertholon 2002, Crevits 2004).
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Not So Benign PositionalVertigo
• Persistent positional nystagmus may
signify structural pathology
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Persistent ApogeotropicNystagmus
• 50% of cases have associated caloric orvestibular test abnormalities
• Etiologies may include limited vestibular
neuritis (unilateral utricular nervesectioning in animal models producesapogeotropic positional nystagmus) or
structural abnormalities• Cerebellar degeneration (seen in older
adults)
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Horizontal positionalnystagmus
• Low-amplitude (6 d/s or less) scatteredhorizontal positional nystagmus is anon-localizing, non-specific finding.
• Unidirectional nystagmus may be seenin vestibular neuritis (uncompensated),Meniere’s (to either the affected or
unaffected ear) or central pathologysuch as stroke, multiple sclerosis ortumor (acoustic neuroma or cerebellar).
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Conclusions
• Semicircular canal variants andconversions are seen in about 20% ofcases. Supine head turn positioning is
helpful in diagnosing lateral semicircularcanal BPPV
• Examining the nystagmus during
repositioning allows for greater success• Persistent positional nystagmus
warrants further evaluation