Benign Paroxysmal Positional Vertigo Amy Stinson MS IV Kansas City University of Medicine.
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Transcript of Benign Paroxysmal Positional Vertigo Amy Stinson MS IV Kansas City University of Medicine.
BPPV
Most common cause of peripheral vertigo Most common identifiable cause – Head
trauma, 2nd – vestibular neuronitis Predisposing factors: infection, surgery, prolonged
bed rest, Meniere’s disease Usually idiopathic 50 – 70% Incidence 64:100,000 every year 20-30% of diagnosed vertigo
History
1921 – Barany 1952 – Dix and Hallpike 1969 – Schuknecht
Proposed posterior canal crista was source of dysfunction Loose otoconia from utricle deposited on cupula Cupulolithiasis Concluded that ampullofugal (excitatory) deflection of
posterior canal cupula accounts for nystagmus
History
1979 - Hall, Ruby & McClure BPPV results from deflection of posterior canal
cupula because of the motion of debris within the posterior canal
Canalithiasis This accounted for fatigability of nystagmus
1985 – McClure – horizontal canal BPPV 1994 – Brandt – anterior canal BPPV
Anatomy
Vestibular portion of CN 8 arises in Scarpa’s ganglion in internal auditory meatus
Peripheral processes of bipolar ganglion cells terminate in hair cells of sensory epithelium of the labyrinth
Hair cells sit on the surface of cristae Cristae ampullaris – SCC Maculae acousticae – utricle and saccule
Hair cells are covered by: Cupula - SCC Otolithic membrane - maculae
Brodel M: Three unpublished drawings of the anatomy of the human ear, Philadelphia, WB Saunders, 1946
Anatomy
Semicircular canals Ampullae senses head
turning – angular acceleration
Endolymph w/in canal causes cupula to move
deflection of hair cells sensation of rotation
Utricle and Saccule Maculae senses gravity
and head tilt – linear acceleration
Hairs are displaced in response to gravity on otoliths sensation of tilt
Pathogenesis
Canalolithiasis Most widely accepted hypothesis of BPPV Otoconia become displaced from utricular macula.
Because the particles are heavier than surrounding endolymph, they tend to collect in the long arm of the posterior semicircular canal.
Once the particles clump into a sufficient mass, changes in head position cause gravitation of the particles hydrodynamic drag on the endolymph displacing the cupula
Pathogenesis
5 Typical Features of PC –BPPV 1. The canalithiasis mechanism explains the latency of
nystagmus as a result of the time needed for motion of the material within the posterior canal to be initiated by gravity
2. The nystagmus duration is correlated with the length of time required for the dense material to reach the lowest part of the canal
3. The upbeating (vertical) and torsional components of nystagmus are consistent with eye movements evoked by stimulation of the posterior canal nerve
Pathogenesis
4. The reversal of nystagmus when the patient returns to sitting upright position is due to retrograde movement of particles in PC lumen back towards the ampulla
5. The fatigability of nystagmus evoked by repeat Dix-Hallpike positional testing is explained by dispersion of particles within the canal
Pathogenesis
Horizontal(Lateral) Canal – BPPV 2 - 15% BPPV pts Idiopathic, minor head trauma, complication of Tx of
PC-BPPV Turning the head while supine evokes severe vertigo Cupulolithiasis plays a greater role Resulting nystagmus is horizontal
Geotropic – toward undermost ear Apogeotropic – beats away from undermost ear (rarer)
Pathogenesis
Anterior Canal – BPPV Similar provoking factors as LC and HC – BPPV Nystagmus is downbeat and torsional Latency, duration & fatigability are similar
Case
69 yo female c/o several months of episodic dizziness described as spinning and imbalance associated with severe nausea
Last episode occurred when she got out of bed and felt dizzy within seconds
She has awakened from sleep with a swimming sensation She has had spinning sensations lasting less than a minute
when reaching into an upper cupboard Pt admits to being a “fender bender” a few months ago while
snowbirding down in Florida
Case
Exam is normal except for paroxysmal positional upbeating and counterclockwise torsional nystagmus with Dix-Hallpike positioning to the right side
Canalith repositioning is performed with resolution of her nystagmus upon repeat positioning
Clinical Evaluation
50 y/o Female Recurrent episodes of vertigo lasting less
than one minute (usually a few seconds) Associated with change in head position Nausea and vomiting Symptoms may fatigue as day progresses Episodes can continue for weeks to months
Clinical Evaluation
Normal neurologic exam Normal hearing test and tympanogram No spontaneous nystagmus Dix-Hallpike test
1-2 sec latency of onset of vertigo and nystagmus Nystagmus is classically torsional (rotatory) with vertical
component (counterclockwise for right ear and clockwise for left ear)
Nystagmus is fatigable with repeated tests
Clinical evaluation
Roll test Log roll or barbeque test Supine head turning elicits horizontal (lateral)
canal BPPV
Anterior canal BPPV most commonly spontaneously resolves
Treatment
Repositioning maneuvers Epley – effective in over 90% of cases
Most effective for PC-BPPV Sermont – more difficult to perform
No advantage over Epley After maneuvers, pts should avoid bending over
and should sleep with their head elevated at least 45° for the next 48 hrs
Treatment
Surgical Singular neurectomy –
For Highly intractable BPPVThe post. ampullar br. of vestibular nerve is transected
just before it enters the amupllaComplete resolution in 80 – 97% of ptsSensorineural hearing loss 4 – 6%
Treatment
Surgical Posterior Semicircular Canal Occlusion
Obstruction of canal lumen preventing the flow of endolymph
This fixes the cupula and renders it unresponsive to angular acceleration
Post-op imbalance and disequilibrium and transient sensorineural loss that usually resolves within a few weeks
Prognosis
Natural history of BPPV includes acute onset and remission over a few months
90 – 95% of pts will respond to one repositioning maneuver
Pts can have unpredictable recurrences that often respond to a repositioning maneuver
With intractable disease posterior canal occlusion is safe and reasonable option
References
Cummings: Otolaryngology: Head & Neck Surgery, 4th Ed. UpToDate: Positional vertigo and nystagmus Fife, TD. Recurrent positional vertigo. Continuum: Lifelong learning in neurology. Aug 2006. 12:92-115. Quinn, FB. Ryan, MW. Medical management of vestibular disorders and vestibular rehabilitation. Grand
rounds, UTMB Dept. of Otolaryngology. 2004. Adams and Victor’s Neurology. Deafness, Dizziness, and Disorders of equilibrium. Chap 15. 2006. Lange Neurology. Disorders of Equilibrium. Peripheral vestibular disorders. Chap 3. 2006. Lange. Current Diagnosis and treatment of Otolaryngology – Head and neck surgery. Vestibular system.
Chap 43. 2004. Shaia, WT et al. Success of Posterior Semicircular Canal Occlusion and Application of the dizziness
Handicap Inventory. Otolaryngology – Head and neck surgery. 2006. 134:424-430. White, JA. Oas, JG. Diagnosis and Management of Lateral Semicircular Canal Conversions during Particle
Repositioning Therapy. Laryngoscope. 2005. 115:1895-1897. Virre, E. Purcell, I. The Dix-Hallpike Test and the Canalith Repositioning Maneuver. Laryngoscope. 2005.
115:184-187. Woodworth, BA. Et al. The Canalith Repositioning Procedure for Benign Positional Vertigo: a Meta-
Analysis. Laryngoscope. 2004. 114:1143-1146.
References
Kos, MI. Et al. Transcanal approach to the Singular Nerve. Otology and Neurotology. 2006. 27:542-546.
Parnes, LS. Agrawal, SK. Diagnosis and management of benign paroxysmal positional vertigo. CMAJ. 2003. 169:681-693.
Walsh, RM. Bath, AP. Cullen, JR. Long-tern results of posterior semicircular canal occlusion for intractable benign paroxysmal positional vertigo. Clinical Otolaryngology & Allied Sciences. 1999. 24:316-323.
Sekine, K. Imai, T. et al. Natural History of benign paroxysmal positional vertigo and efficacy of Epley and Lempert maneuvers. Otolaryngology – Head & Neck Surgery. 2006. 135:529-533.
White, JA. Coale, KD. Diagnosis and management of lateral semicircular canal benign paroxysmal positional vertigo. Otolaryngology – Head & Neck Surgery. 2005. 133:278-284.
Korres, SG. Diagnostic. Pathophysiology, and therapeutic aspects of benign paroxysmal positional vertigo. Otolaryngology – Head & Neck Surgery. 2004. 131:438-44.