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| ===Common Causes=== | | ===Common Causes=== |
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| ''' Distinguish cause of vertigo based on: '''
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| ::* Time course
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| ::* Duration
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| ::* Recurrence
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| * Lasting a day or longer
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| *:* Vestibular neuronitis
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| *:*:* Onset over hours, peaks in first day, improves within days
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| *:*:* May recur episodically for weeks to months
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| *:* Vertebrobasilar ischemia with labyrinth infarct
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| *:*:* Abrupt onset, improves within 1 week
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| *:*:* Symptomss resolve within weeks to months
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| *:* Brain-stem stroke: usually other symptoms vertebrobasilar ischemia
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| *:* Inferior cerebellar infarct/bleed: similar symptoms/time course to vestibular neuritis
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| *:* Multiple sclerosis: vestibular symptoms evolve over hours to days
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| * Lasting minutes to hours
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| *:* Meniere’s disease: episodic/recurrent
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| *:* Vertebrobasilar transient ischemic attack (TIA): typically lasts < 30 minutes, may recur
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| *:* Migraine Headache: episodic/recurrent
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| *:* Perilymph fistula: episodic; precipitated by exertional straining or change in air pressure
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| * Lasting seconds
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| *:* Benign paroxysmal positional vertigo (BPPV): usually lasts < 1 minute
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| ''' Alternative anatomic classification: central vs. peripheral '''
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| * Central (20%):
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| *:* Caused by damage to vestibular structures in brainstem or cerebellum
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| *:* Associated with other brainstem deficits
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| *:* Vertigo and nystagmus can be bidirectional or vertical
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| *:* Vertebrobasilar insufficiency:
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| *:*:* Accounts for ½ of central causes
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| *:*:* Brainstem or cerebellar territory (anterior inferior cerebellar artery (AICA), posterior inferior cerebellar artery (PICA)) -> transient ischemic attack (TIA) or [[Ddx:Cerebrovascular Accident|cerebrovascular accident]] (CVA)
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| *:*:* Associated diplopia, dysarthria, dysphagia, hemiparesis, etc.
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| *:*:* Cerebellar infarct may present with isolated vertigo
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| *:*:* Can have pontine lacunes, labyrinthine infarcts
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| *:* Multiple sclerosis: associated brainstem symptoms may be subtle (facial numbness)
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| *:*:* Vertiginous symptoms may be sudden, transient, recurrent or persistent
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| *:* Migraine: vertigo precedes headache and may last afterward
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| *:*:* Atypical form of migraine with aura -> may respond to migraine therapy
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| *:* Drugs
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| *:*:* Sedatives, anticonvulsants may cause central vertigo in high/excess doses
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| *:*:* Anticonvulsants in prescription doses may cause nystagmus (phenytoin, carbamazepine)
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| * Peripheral (80%):
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| *:* Caused by damage to vestibular labyrinth, vestibular nerve
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| *:* Associated tinnitus, hearing loss if auditory component of CN VIII affected
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| *:* Vertigo and nystagmus are unidirectional, and not vertical
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| *:* BPPV
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| *:*:* Accounts for more than ½ of cases peripheral vestibular dysfunction
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| *:*:* Common in the elderly (patients usually > 60)
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| *:*:* Episodes of sudden onset, short duration -> condition often remits in 6 months
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| *:*:* Mechanism = stimulation of labyrinth by debris in posterior semicircular canal
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| *:* Vestibular neuronitis
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| *:*:* Accounts for ¼ of cases peripheral vestibular dysfunction
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| *:*:* Isolated vertigo due to viral infection involving labyrinth (after URI)
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| *:* Acute labyrinthitis
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| *:*:* Viral involvement of cochlea and labyrinth after upper respiratory infection (URI)
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| *:*:* Vertigo associated with tinnitus and hearing loss
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| *:*:* symtpoms resolve completely within 3-6 weeks
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| *:* Meniere’s disease
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| *:*:* Idiopathic endolymphatic hydrops -> damage to hair cells
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| *:*:* Tinnitus, ear pressure and hearing loss associated with vertigo
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| *:*:* Paroxysmal episodes lasting minutes to hours
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| *:*:* Frequency of episodes waxes and wanes over time
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| *:*:* Hearing loss can become permanent
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| *:* Acoustic neuroma
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| *:*:* Benign tumor, but can cause brainstem compression if unprescribed
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| *:*:* Retrocochlear hearing loss, tinnitus, vague dizziness
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| *:*:* Very gradual symptom onset with progressive asymmetric hearing loss
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| *:*:* Vertigo not prominent because gradual time course allows central nervous system adaptation
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| *:* Ototoxins: hearing impairment usually >> vestibular symptoms
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| *:*:* Gentamicin, streptamicin most injurious to vestibular portion of CN VIII
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| ==References== | | ==References== |