![]() ![]() Additionally, hyperventilation and changes in cerebrospinal fluid (CSF) pH that occur with strenuous activity may also lead to 8th cranial nerve hyperexcitability in vestibular paroxysmia or with acoustic neuroma. If vertigo occurs with exertion when the head is stationary, however, cardiopulmonary disorders should be considered. Exertion-related vertigo may be caused simply by activities leading to head movements that trigger positional or head motion-induced symptoms. Symptoms triggered by going from sitting to lying or rolling over in bed (both cause a change in gravitational vector), in contrast, favor BPPV.Įxertion. If symptoms are triggered by standing up from sitting when there is no change in spatial orientation of the head with respect to gravity (eg, standing from a chair without moving the head), orthostatic hypotension is favored. Triggered by changing from a seated to standing position or from lying to seated, orthostatic vertigo and may be related to a neurologic condition (eg, multiple system atrophy), medications (eg, antihypertensives), hypovolemia, or presyncope. Patients with CVS have constant vestibular symptoms for weeks to years (eg, bilateral vestibular loss).Ī convenient strategy is to employ a 2-layer approach to acute and episodic clinical syndromes (Figures 1-4). Patients with EVS have similar symptoms and signs as AVS, lasting seconds to hours (eg, Ménière’s disease, VM). Patients with AVS present with more than 24 hours of continuous vertigo (lasting days to weeks and monophasic) with nausea/vomiting, imbalance, head motion intolerance, spontaneous nystagmus (eg, stroke or vestibular neuritis). Vestibular disorders can be grouped by presentation into acute, episodic, and chronic vestibular syndromes (AVS, EVS, and CVS, respectively). For example, a patient with BPPV may overestimate attack duration (eg, 5 minutes) because of persisting vegetative symptoms (eg, nausea, vomiting, and sweating) even when the spinning associated with BPPV lasted less than 1 minute. In episodic conditions, asking the patient how long the specific vestibular symptom lasted (ie, dizziness or vertigo), rather than how long an attack lasted, can give a better estimate of duration. ![]() Patients with bilateral vestibular loss (BVL), uncompensated unilateral vestibular loss (UVL), chronic intoxication, or persistent postural perceptual dizziness (PPPD) often have months to years of symptoms. In patients with with vestibular neuritis or central vestibular lesions from stroke or demyelination, vertigo lasts days to weeks. Patients with Ménière’s disease, vestibular migraine (VM), or transient ischemic attacks (TIAs) often present with vertigo spells lasting minutes to hours. Vertigo spells are brief, usually lasting seconds in patients with BPPV, vestibular paroxysmia, and cardiac arrhythmias. 5 Understanding the direction of vertigo can occasionally help lateralize the disorder or better understand the pathophysiology. 4 Spinning vertigo that changes direction during a single event, is unique to Ménière’s disease and related to the phases of the attack-excitatory, inhibitory, or recovery. In some vestibular disorders (eg, vestibular paroxysmia), patients have directionally specific spinning that may be better recognized in vertigo than in external vertigo. Patients may also have symptoms that transition from one to another over time for example, acute vertigo to chronic unsteadiness. For example, a common combination of symptoms in vestibular neuritis includes vertigo (due to semicircular canal imbalance) and oscillopsia (due to horizontal jerk nystagmus). Patients may have more than a single symptom at a time. 1 Orthostatic hypotension and benign paroxysmal positional vertigo (BPPV), for instance, can both induce vertigo or dizziness, 2,3 although the term vertigo will be used throughout this article to describe either symptom. Purposefully, the definitions do not suggest a particular disease pathophysiology. ![]() ![]() Dizziness is a nonmotion sensation of disrupted spatial orientation. The feeling of being unstable without a particular direction preference while sitting, standing, or walking is unsteadiness. External vertigo is a false or distorted sensation of the surroundings, excluding bidirectional motion, which is known as oscillopsia. Internal vertigo is a false or distorted sensation of self-motion including spinning, swaying, bobbing, tilting, bouncing, and sliding. In 2009, the Barany Society published the first consensus classification of vestibular symptoms. In the next issue, Part 2 covers the oculomotor and vestibular examinations. A stepwise and careful history helps identify the many causes of vertigo and dizziness. ![]()
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