See also "Syncope"
I. Types of dizziness
- Vertigo: an illusion of movement, us. rotation
- Arises from disturbances of vestibular system or neural structures afferent to this (CN VIII, cerebellum, brainstem nn, c-spine proprioceptive fibers)
- Causes include BPV, labyrinthitis, vertebrobasilar TIA/CVA, & Meniere's disease
- Accompanying nausea suggests peripheral rather than central etiology, as do ear symptoms
- Presyncope: a sensation one is about to lose consciousness, with lightheadedness and sometimes nausea or falling. n.b. syncope alone can give brief eye-rolling and myoclonus, like sz, from hypoxia
- Arises from cerebral hypoxemia, us. from ischemia
- Can be precipitated by vol. depletion, meds, EtOH, vagal surge, infection, orthostatic hypotension (e.g. from meds, autonomic insufficiency), arrhythmias
- Other causes include anemia, CO poisoning, pulmonary disease, MI, aortic stenosis, adrenal insufficiency, "subclavian steal"
- Represents global, not local, cerebral hypoxia, so not the same as TIA
- Dysequilibrium: a sense of imbalance, "a body sensation more than a head sensation"
- Results from disruption of the balance system, e.g. vestibulospinal, proprioceptive pathways, vestibular system, cerebellum, visual system, peripheral motor nn, muscles, cerebral cortex.
- Usually multifactoria, e.g. mixed motor & visual impairment
- Dizziness associated with psychiatric problems, e.g. anxiety. Often accompanied by symptoms of dissociation
- Multiple neurosensory impairments, involving cognitions, vision, proprioception, vestibule, cerebellum, motor weakness, etc.
II. Evaluation
- Very common in elderly, not associated with increased risk of death
- May frequently be due to more than one problem and can't always make dx immed.
- Px:
- Vital signs with orthostatics
- Fundoscopy
- Cranial nn. exam, with check for nystagmus & hearing
- Otoscopy with insufflation
- Tandem gait
- Romberg
- Carotid upstrokes
- C-spine ROM
- Forced hyperventilation if suspect panic disorder
- Hallpike-Dix Maneuver
- March in place for 30sec w//eyes shut and arms extended; if vestibular dysfunction exists, will rotate >30'
III. Clinical entities
- Destruction of 1 or more labyrinths from viral or vascular cause
- Occas. preceded by viral-like illness
- Rapid-onset vertigo with n/v, diaphoresis, & horizontal nystagmus
- May get hearing loss & tinnitus if auditory apparatus affected
- Young people generally spontaneously improve in 1-2d as their brains learn to substitute other sensory info for lost vestibular info
- Older pts may have vertigo or other dizziness sx for months-yrs b/c of decreased sensory balance reserve, theoretically
- Treatment
- Meclizine or promethazine for symptomatic relief
- Low-dose benzodiazepines may relieve protracted sx
- Methylprednisolone x 3wks (starting at 100mg/d then tapering) was ass'd with sig. greater improvement in vestibular paresis as assessed by computer analysis of caloric irrigation at 1y c/w placebo in a randomized trial of 141 pts with acute labyrinthitis, though valacyclovir 100mg TID x 1wk, in the same trial (2 x 2 factorial design), was not (NEJM 351:354, 2004--JW)
- TIA's of vertebrobasilar system (ant. circ. dysfn shouldn't cause dizziness)
- Vertigo often w/ ataxia, dysarthria, diplopia, hemiplegia/hemianesthesia
- Occas. get HA; rarely get syncope
- <50% go on to have CVA
- Tx = control of risk factors & give ASA
- "Subclavian steal" sd. = a treatable form (surgically?)
- CVA of vertebrobasilar system: presents similarly to TIAs
- Migraine: can give sx similar to vertebrobasilar TIA, in fact, hard to distinguish the two. Migrain more likely to show scotomata or other visual disturbances; migratory paresthesias; progression from one sx to another
- Benign positional vertigo
- Very common; caused by vestibular damage (e.g. from infection, trauma); otoliths loose in a semicircular canal; eventually are reabsorbed or scarred over
- Described by Hallpike and Dix as "positional nystagmus"in their landmark paper (Ann. Otol. Rhin. Laryngol. 6:987, 1952): "The giddiness comes on when [the pt] lies down in bed or when such a position is taken up during the day; for instance, in lying down beneath a car or in throwing the head backward to paint a ceiling...he may be able to cause his vertigo to disappear by maintaining his head in the disagreeable position, or by taking up this position slowly."
- Sx occur only during or after position changes; last only seconds to a minute
- Come in flurries of attacks for 1-2wks then months-yrs without sx; may or may not recur
- No other neurologic sx (except maybe nau/vom); no auditory sx; benign course
- Dx = Hallpike-Dix maneuver
- Tx
- Positional exercises x hrs at a time to fatigue response, e.g. "Epley" procedure
- Falling rapidly to one side or the other from a sitting position in bed
- Meds generally not helpful
- Backward but not forward rotation in a flight simulator ("canal-clearing" procedure) was effective at resolving sx in 2/3 of patients with BPV (Neurology 49:720, 1997 and BMJ 311:489, 1995-JW)
- A "canalith repositioning procedure" was sig. more likely than a sham procedure (50% vs. 19%) to result in resolution of BPV sx in a randomized trial of 50 pts with BPV (Mayo Clin. Proc. 75:695, 2000--JW)
- Central positional vertigo
- Arises in certain positions
- No latency or fatiguability on provocational testing like BPV
- Causes include tumor, posterior CVA, MS, vertebral artery impingement
- Meniere's disease
- Vertigo, tinnitus, and hearing loss in a recurrent pattern
- Hearing loss is low-frequency; initially only during the vertigo attacks, then continuous
- Attacks us. last 2-12h
- Thought to be from altered lymphatic flow in inner ear
- Treatment = salt restriction & diuretics. During acute attack, can try low-dose antihistmines, inc. meclizine, demenhydrinate
- Recurrent vestibulopathy: common but poorly understood
- Vertigo with n/v, nystagmus, in a recurrent pattern, e.g. Qyr
- Most resolve in a few yrs, some continue, some change to BPV, some to Meniere's
- Tx = meclizine
- Bilateral vestibular dysfunction, e.g. from aminoglycosides
- Get dysequilibrium, worse while standing
- Get feeling of oscillopsia (eyes bouncing up & down) when walking
- Cervical vertigo
- Vertigo or more vague lightheadedness, from irritation of proprioceptive c-spine fibers, e.g. from DJD or mm. spasm
- Often accompanied by occas. HA or neck stiffness/pain
- Tx = treat underlying problem
- Middle ear disease, e.g. serous otitis, cholesteatoma, cerumen against TM
- Can give vertigo or vague lightheadedness
- Often with sensation of ear stuffiness
- Neurosyphilis
- Usually bilat. hearing loss; vertigo a less prominent symptom
- Perilymphatic fistula
- Disruption in round window, so that perilymph goes into middle ear; usually resulting from trauma, e.g. head bonk or noise
- Get persistent dysequilibrium & vertigo precipitated by cough/straining
- Can sometimes precipitate vertigo with pneumatic otoscopy
- Acoustic neuroma
- Presents with unilateral hearing loss; occasionally with continuous lightheadedness or vertigo
- Dx = audiometry w/ speech discrimination; MRI
- Continuous (vs. episodic) dizziness
- Rare; usually from multiple neurosensory deficits vs. psych; the latter is suggested by sx of dissociation ("floating," etc.), or other somatic complaints
- Other causes include cerebellar atrophy, anemia, MI or other acute illness, or s/p posterior CVA (after acute vertigo is resolved)
- Ocular dizziness: symptomatology can be any form of dizziness
- Caused by change in corrective lens, fluctuation in glucose, or cataract surgery
IV. Treatment principles
- Antihistamines & sedatives can worsen the problem, but in low doses may help
- Meniere's may respond to Na restriction and diuretics
- For BPV
- Maneuvers designed to reposition otoliths and/or "vestibular rehabilitation" have been shown effective (e.g. Mayo Clin. Proc. 75:695, 2000--AFP)
- Deconditioning can worsen things, so physical therapy may help
- Treat visual problems, e.g. cataracts, if possible
- A single session of "vestibular rehabilitation" with instructions to do specific exercises BID x 3mos (various head movements w/eyes open & closed) was ass'd with sig. higher incidence of clinically significant improvement in sx (67% vs. 38%) c/w "usual care" in a randomized trial in 170 adults with > 2mos of movement-provoked dizziness (mixed Meniere's, labyrinthitis, BPV, and unknown etiology) (Ann. Int. Med. 141:598, 2004--JW)