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CHAPTER 170: Vertigo 1145 weakness of the lower extremities. Senile gait disorder is thought to exist in up to one fourth of the elderly population. Some authorities divide this disorder into components of gait ataxia with mild truncal instability and widened gait, and gait slowing with diminished spontaneous arm swing and bradykinesia. 9 However, elements of the senile gait are also found in neurologic diseases, so consider the possible presence of a disorder such as Parkinson’s disease or normal pressure hydrocephalus in elderly patients with gait impairment. 9 Patients unable to walk or care for themselves, or with increasing falls at home, need admission for diagnosis and supportive care planning.  THE ALCOHOLIC PATIENT A history of alcoholism or malabsorption problem in the patient with ataxia or gait disorder raises the possibility of a potentially remedial nutritional problem. If acute motor ataxia is present with confusion or eye movement abnormalities, consider Wernicke’s disease and administer IV thiamine. 10 The entity of alcoholic cerebellar degeneration (sometimes referred to as rostral vermis syndrome, because a portion of the cerebellar vermis is preferentially affected) may represent the same nutritional deficiency and not the direct toxic effects of alcohol.  CHILDREN In evaluating children with acute ataxia or gait disorder, examination must exclude weakness and musculoskeletal disorders. The child may be awake, alert, and playful but is visibly unsteady or wobbly sitting on a stretcher. The differential diagnosis is extensive ( Table 169-3). Acute or deteriorating presentation generally mandates an aggressive search for the underlying cause and will likely need inpatient management. Intoxications are a cause of ataxia in children, and ingestions may be surreptitious. History should include queries about any TABLE 169-3 Causes of Acute Ataxia in Children, Roughly in Order of Frequency Cause Example Drug intoxication Ethanol Isopropyl alcohol Phenytoin Carbamazepine Sedatives Lead, mercury Idiopathic Acute cerebellar ataxia of childhood Infection and inflammation Varicella Coxsackievirus A and B Mycoplasma Echovirus Postinfectious inflammation Postimmunization Neoplasm Neuroblastoma Other CNS tumors Paraneoplastic Opsoclonus-myoclonus syndrome Trauma Subdural or epidural posterior fossa hematoma Congenital or hereditary Pyruvate decarboxylase deficiency Friedreich’s ataxia Hartnup disease Hydrocephalus Cerebellar abscess Labyrinthitis/vestibular neuronitis Transverse myelitis Meningoencephalitis medications in the household. Acute ataxia may follow immuniza tions, viral illnesses, or varicella, which has been rarely reported in the preeruptive phase of varicella. 12 Most children are in the 2- to 4-year-old range. Acute cerebellar ataxia of childhood is thought to be a postinfectious demyelinating disorder. The onset of gait ataxia is abrupt, and only occasionally is fever present at the time ataxia begins. The latency from the prodromal illness to the onset of ataxia is from 2 days to 2 weeks. Other neurologic findings encountered included truncal ataxia, dysmetria, and, uncommonly, cranial nerve abnormalities. Patients with ataxia following varicella appear to have uniform excellent recovery compared with patients with acute cere bellar ataxia of other causes who may have some residual problems.

to 2 weeks. Other neurologic findings encountered included truncal ataxia, dysmetria, and, uncommonly, cranial nerve abnormalities. Patients with ataxia following varicella appear to have uniform excellent recovery compared with patients with acute cere bellar ataxia of other causes who may have some residual problems. Little workup is needed if the ataxia occurs in the convalescent phase of varicella, and antiviral medications are not indicated. Otherwise, neuroimaging, lumbar puncture, and consultation are advisable. One study showed that although roughly half of the patients had cere brospinal fluid inflammatory changes with pleocytosis or elevated immunoglobulin G index, in only a minority of cases did MRI iden tify inflammatory changes in the cerebellum. 12 Another small report noted MRI abnormalities not only in the cerebellum but also in other areas of the CNS. This “syndrome” may in fact consist of several sub groups, some of which involve transient demyelination. Posterior fossa mass lesions and other CNS masses may present with ataxia, although usually some additional abnormalities of cranial nerves or strength will be discovered with careful examination. Atten tion is needed to exclude abnormalities on physical examination that might suggest problems not localized to the cerebellum. Abnormal ocular movements should increase the suspicion of a mass lesion. Acute ataxia associated with rapid chaotic eye movements (opsoclonus) and myoclonic jerks of the head and extremities is the striking syndrome of opsoclonus-myoclonus. This may be a postviral syndrome but is often a paraneoplastic syndrome associated with a neuroblastoma located in the abdomen or chest. Unusual metabolic disorders such as pyruvate decarboxylase complex deficiency may present with ataxia. Family history may or may not suggest a metabolic disorder. Typically, the onset is gradual, but abrupt decompensations may occur. Other systemic or CNS abnormalities will be present. REFERENCES The complete reference list is available online at www.TintinalliEM.com. Vertigo Brian Goldman Peter Johns INTRODUCTION AND EPIDEMIOLOGY Vertigo is defined as the sensation of self-motion when no motion is occurring. Vestibular disorders are conditions that affect the vestibular sensory organs in the inner ear or the cerebellum and brainstem and the connections between them. Some patients have difficulty describing the sensation of vertigo. 1 Dizziness is a nonspecific word patients use to describe vertigo, but is also used by some patients to describe the symptoms of presyncope, imbal ance, lightheadedness, and other sensations. Assess patients for nonvestibular causes of dizziness such as orthostatic hypotension, presyncope, and new medications such as antihypertensives. Vertigo is a diagnostic challenge because it has many potential causes (Table 170-1). CHAPTER Tintinalli_Sec14_p1101-1186.indd 1145 8/2/19 12:08 PM

ess, and other sensations. Assess patients for nonvestibular causes of dizziness such as orthostatic hypotension, presyncope, and new medications such as antihypertensives. Vertigo is a diagnostic challenge because it has many potential causes (Table 170-1). CHAPTER Tintinalli_Sec14_p1101-1186.indd 1145 8/2/19 12:08 PM 1146 SECTION 14: Neurology Three of the most common vestibular disorders are featured prominently in this chapter. These are benign paroxysmal positional vertigo (BPPV), vestibular neuritis, and cerebellar/brainstem stroke. The term Acute Vestibular Syndrome (AVS) is sometimes used to describe the entities of vestibular neuritis and cerebellar/brainstem stroke. BPPV is the most common cause of vertigo in all clinical settings including the ED. The condition occurs when otoconia (which nor mally reside in the utricle) are displaced spontaneously or by trauma or infection into the semicircular canals. As a result, when patients move their head in certain positions, they experience vertigo and nystagmus, sometimes very intense, for less than 2 minutes, often around 20 seconds. BPPV can be diagnosed easily with a bedside test and is highly responsive to treatment with the Epley or other particle repositioning maneuvers. Vestibular neuritis is the second most common peripheral cause of vertigo. Sometimes erroneously mislabeled as labyrinthitis by some clinicians, the condition is believed to be caused by a deficit in one of the vestibular nerves. The likely cause is a virus. The patient develops a prolonged, continuous bout of vertigo that is intense for several days and then resolves over days, weeks, or months. There is no associated ear pain, hearing loss, or tinnitus in vestibular neuritis. Labyrinthitis, a complication of acute otitis media, is less common than vestibular neuritis but can present in a similar manner, with days of ongoing, continuous vertigo and nystagmus. Unlike vestibular neuritis, patients with labyrinthitis complain of ear pain, hearing loss, or tinnitus as well as vertigo. Cerebellar/brainstem stroke (hereafter referred to as cerebellar stroke) is the most feared cause of vertigo. Patients with cerebellar stroke may develop edema causing acute hydrocephalus or brainstem compression that leads to increased disability or death. Many patients present with neurologic symptoms such as limb weakness or paresthesia, diplopia, or TABLE 170-1 Peripheral and Central Causes of Vertigo Peripheral Causes Relative Frequency of Presentation to the ED Key Points Clinical Course Benign paroxysmal positional vertigo The most common cause of vertigo Less than 2-minute episodes of vertigo, initiated by head movement. Dix-Hallpike test shows vertical upward and rotatory nystagmus. Benign, particle repositioning maneuvers is first-line treatment. Medications rarely indicated. Vestibular neuritis Common Hours/days of continuous, constant vertigo. Use HINTS plus exam if nystagmus present. Spontaneous improvement over days/weeks. Labyrinthitis Less common Ear pain, tinnitus, and hearing loss onset 1 or more days before vertigo; otherwise similar to vestibular neuritis. A complication of otitis media. Serious if bacterial (rare). Ménière’s disease Less common Recurrent episodes of vertigo, hearing loss, tinnitus, and ear fullness. Slowly progressive; can lead to profound hearing loss. Perilymph fistula Rare Vertigo and hearing loss after head trauma or pressure changes to middle ear (flying/diving/nose blowing). Can benefit from surgical correction. Superior canal dehiscence Rare Vertigo brought on by loud sounds, coughing, and straining. Surgery for severe cases. Vestibular schwannoma Rare Slow onset of hearing loss, tinnitus, and less commonly, vertigo. Slowly growing; amenable to surgery if growing and symptomatic.

lowing). Can benefit from surgical correction. Superior canal dehiscence Rare Vertigo brought on by loud sounds, coughing, and straining. Surgery for severe cases. Vestibular schwannoma Rare Slow onset of hearing loss, tinnitus, and less commonly, vertigo. Slowly growing; amenable to surgery if growing and symptomatic. Central Causes Vestibular migraine Most common central cause of vertigo, but much underdiagnosed. Recurrent attacks in patients with migraine, including episodes of isolated vertigo. About half the episodes have migrainous features. Most experts recommend treatment as per migraine headache. Cerebellar/brainstem stroke Less common Often presents with other neurologic signs or symptoms, but can present with symptoms similar to vestibular neuritis; use HINTS plus exam if nystagmus is present. Hearing loss can occur at onset of stroke. Admit to hospital, as patients can develop edema and/ or hydrocephalus, leading to coma/death. Posterior circulation transient ischemic stroke Less common Usually presents with other neurologic signs or symptoms. Can present shortly before stroke. Cerebellar hemorrhage Less common Significant ongoing headache; possibly decreased level of consciousness. Neurosurgical consult; tonsillar herniation or hydrocephalus can occur. Abbreviation: HINTS = head impulse test, nystagmus, test of skew. dysarthria, but some present without these features; as such, the condi tion may resemble vestibular neuritis. When patients are discharged from the ED with a diagnosis of peripheral vestibular disorder, the frequency of missed strokes is very low, about .41%(2). The fear of missing a stroke can lead the clinician to pursue advanced diagnostic imaging in patients with benign peripheral conditions. Fortunately, the most common peripheral causes of vertigo presenting to the ED, BPPV and vestibular neuritis, can often be differentiated from cerebellar stroke by history, physical examination, and focused bedside testing. PATHOPHYSIOLOGY The CNS coordinates and integrates sensory input from the visual, vestibular, and proprioceptive systems. Vertigo arises from a mismatch of information from two or more of the involved senses, caused by dysfunction in the sensory organ or its corresponding pathway. Visual inputs provide spatial orientation. Proprioceptors help relate body movements and indicate the position of the head relative to that of the body. The vestibular system (via the otoliths) establishes the body’s orientation with respect to gravity. The cupula’s sensors track rotary motion. The three semicircular canals sense orientation to movement and head tilts and are filled with a fluid called endolymph. The move ment of fluid in the semicircular canals causes specialized hair cells inside the canals to move, causing afferent vestibular impulses to fire. Sensory input from the vestibular apparatus travels to the nucleus of the eighth cranial nerve (Figure 170-1). The medial longitudinal fasciculus, the red nuclei, the cerebellum, the parietal lobes, and the superior temporal gyrus of the cerebral cor tex integrate the various sensory inputs. Connections between these Tintinalli_Sec14_p1101-1186.indd 1146 8/2/19 12:08 PM

to the nucleus of the eighth cranial nerve (Figure 170-1). The medial longitudinal fasciculus, the red nuclei, the cerebellum, the parietal lobes, and the superior temporal gyrus of the cerebral cor tex integrate the various sensory inputs. Connections between these Tintinalli_Sec14_p1101-1186.indd 1146 8/2/19 12:08 PM CHAPTER 170: Vertigo 1147 structures and the oculomotor nuclei that drive the vestibulo-ocular reflex complete the system. The vestibulo-ocular reflex prevents visual blurring from head movements and body sway. Balanced input from the vestibular apparatus on both sides is the norm. Unilateral lesions of the vestibular apparatus as well as excessive unilateral firing due to abnormal motion of the endolymph produce imbalanced activity and vertigo. Rapid head movements accentuate the imbalance. Symmetric bilateral damage does not usually produce vertigo but may lead to truncal or gait instability. The prevalence of dizziness increases with age and is due to decreases in visual acuity, proprioception, and vestibular input, plus an increase in free-floating otoconia within the semicircular canals that cause BPPV . Older patients are also more likely to take medications that cause dizziness. CLINICAL FEATURES  OVERVIEW If the presenting complaint points to true vertigo, the history and physical should then focus on a central cause of vertigo. Such neurologic signs and symptoms include focal weakness of the face or limbs, sensory changes, dysmetria (limb or truncal), diplopia, dysarthria, and dysphagia and dysphonia. Spontaneous vertical nystagmus (seen in primary gaze, with the patient looking straight ahead) is also indicative of central vertigo but is seen less commonly than other types of nystagmus, even in cerebellar and brainstem lesions. Short episodes of vertical upward nystagmus with a rotatory component during the Dix-Hallpike test are diagnostic of the most common form of BPPV . Patients who are unable to stand unaided should have a central cause of vertigo ruled out. This is in contrast to the patient with peripheral vertigo; they may be very reluctant to stand or walk but are able in general to do so. A significant and persistent headache that accompanies vertigo sug gests the possibility of a cerebellar hemorrhage, and neck pain suggests vertebral artery dissection. Patients with current or recent transient vertigo who screen posi tive for the neurologic symptoms mentioned previously should have diagnostic imaging as well as referral to a specialist. This method of screening will identify the majority of ischemic or hemorrhagic cerebellar and brainstem strokes causing vertigo, as well as posterior circulation transient ischemic attacks and vertebral artery dissections. Many of the vestibular disorders that cause peripheral and central vertigo are found in Table 170-1.  HISTORY AND PHYSICAL An initial approach to diagnosing acute vertigo, focusing on BPPV , vestibular neuritis, and cerebellar stroke, is shown in the flow chart in Figure 170-2. BPPV comes on abruptly with quick head movements, getting in or out of bed, or rolling over in bed. Patients with orthostatic hypotension complain of dizziness when they stand up but not when they resume the supine position or roll over in bed. If the patient with BPPV remains still, the vertigo usually goes away in less than 1 or 2 minutes. However, the associated nausea and vomiting may persist, prompting the patient to state that the dizziness lasts longer than 2 minutes. In addition, between bouts of vertigo, the patient with BPPV may feel slightly “off ” but without ongoing vertigo or spontaneous nystagmus.

ually goes away in less than 1 or 2 minutes. However, the associated nausea and vomiting may persist, prompting the patient to state that the dizziness lasts longer than 2 minutes. In addition, between bouts of vertigo, the patient with BPPV may feel slightly “off ” but without ongoing vertigo or spontaneous nystagmus. This is contrasted with the presentations of vestibular neuritis and cerebellar stroke in which the patient has persistent and continuous vertigo lasting many hours or days and whose vertigo is made worse by position change. Note that head movements can worsen both central and peripheral vertigo. Assess the patient carefully for nystagmus. The direction of the nys tagmus is defined as the direction of the fast component of the nystag mus. Nystagmus can be horizontal, vertical, rotatory, or a combination. Since nystagmus may be suppressed by visual fixation, avoid having the patient stare at your finger or light source when observing for nystag mus. Observe for spontaneous nystagmus, which can be seen when the patient is looking straight ahead (primary gaze). Also observe for gazeevoked nystagmus by having the patient look approximately 30 degrees from primary gaze to the left and right. To avoid fixation, place a blank piece of paper close to the side of the patient’s head and ask the patient to look through the paper as if it is not there. BEDSIDE TESTING FOR BPPV  PATIENTS WITH EPISODES OF VERTIGO LASTING LESS THAN 2 MINUTES AND INITIATED BY HEAD POSITION CHANGE BUT NO SPONTANEOUS OR GAZE-EVOKED NYSTAGMUS Dix-Hallpike Test The Dix-Hallpike test (DHT) (See Video: Dix Hallpike Maneuver) is used to confirm the diagnosis of posterior canal BPPV , which is the most common form of BPPV . It is appropriate to perform a DHT if a patient has dizziness brought on by head movements only (such as rolling over in bed, lying down, or getting out of bed) that lasts 15 to 30 seconds and has no spontaneous or gaze-evoked nystagmus. Consider pretreatment with an antiemetic only if the patient is having trouble tolerating positional testing or therapeutic maneuvers; it should not be given routinely. Have the patient seated on a stretcher or bed and positioned so that when supine, the patient’s neck can be extended 20 degrees. To observe for nystagmus, instruct the patient to keep the eyes open throughout the test, even if vertigo occurs. To test the left ear, have the patient turn the head 45 degrees to the left. The examiner then quickly brings the patient from a sitting position to a supine position, with the neck extended 20 degrees and head turned 45 degrees to the left. Wait 15 seconds, and if no vertigo or nystagmus occurs, sit the patient up. Test the right side in the same manner, with the head turned 45 degrees to the right (See Video: Performing the Dix-Hallpike Test). A positive DHT consists of a few seconds (up to 15) of latency, in which the patient is asymptomatic, followed by the onset of vertigo with a crescendo-decrescendo pattern of nystagmus that typical lasts roughly 15 to 30 seconds. The nystagmus is a combination of vertical upward and rotatory, with the upper poles of the eyes beating toward the downward ear. When the patient looks more toward the upward ear, the nystagmus becomes more vertical and more rotatory when looking toward the downward ear. 5,6 The downward ear is the affected ear. Otoconia that originate in the utricle have been displaced and are now in the posterior semicircular canal (See Video: Positive Dix-Hallpike Test). Note that HINTS (head impulse test, nystagmus, test of skew) plus testing should not be performed on patients with brief episodes of vertigo or who do not have spontaneous or gaze-evoked nystagmus because lack of nystagmus is a key component of a central cause of Acute Vestibular Syndrome.

Positive Dix-Hallpike Test). Note that HINTS (head impulse test, nystagmus, test of skew) plus testing should not be performed on patients with brief episodes of vertigo or who do not have spontaneous or gaze-evoked nystagmus because lack of nystagmus is a key component of a central cause of Acute Vestibular Syndrome. Upper medulla oblongata Superior vestibular nucleus Medial vestibular nucleus Lateral vestibular nucleusVestibular ganglion Vestibular nerveSuperior semicircular canal Saccule Lateral semicircular canal Posterior semicircular canal Spinal nucleus of accessory (XI) nerve FIGURE 170-1. Vestibular innervation. Tintinalli_Sec14_p1101-1186.indd 1147 8/2/19 12:08 PM

r nucleus Medial vestibular nucleus Lateral vestibular nucleusVestibular ganglion Vestibular nerveSuperior semicircular canal Saccule Lateral semicircular canal Posterior semicircular canal Spinal nucleus of accessory (XI) nerve FIGURE 170-1. Vestibular innervation. Tintinalli_Sec14_p1101-1186.indd 1147 8/2/19 12:08 PM 1148 SECTION 14: Neurology  TREATMENT OF POSTERIOR CANAL BPPV Patients who are diagnosed with BPPV can be treated with the Epley maneuver during their ED visit. 8 The Epley maneuver should be con sidered first-line treatment for posterior canal BPPV . The affected ear is the downward ear when the patient has a positive DHT. Since BPPV can occur in either ear, there is a left and right Epley maneuver (Figure 170-3 and See Video: The Epley Maneuver). In Figure 170-3, the left ear Epley maneuver is shown. Hold each position for the length of time the patient is having vertigo, plus another 30 seconds. The first position is the same as the positive DHT position. Then, without sitting the patient up, the head is rotated 90 degrees to the negative DHT side, the second position. For the third position, the patient is asked to roll on his or her side and the head is rotated another 90 or more degrees in the same direction as the previous step, so that the patient is now looking toward the stretcher or straight down at the floor. In the final step, the patient is asked to move the legs forward off the bed, and the patient is brought to the sitting position, while keeping the head turned in the same direction as in the third position. In the final position, the patient should sit with head upright and looking forward. After 10 minutes, repeat the DHT. If the post-Epley DHT produces no vertigo or nystagmus, the patient can be discharged without any restrictions on activity. It is not unusual for patients whose vertigo and nystagmus have resolved to feel slightly “off ” for a day or two after being treated successfully. However, there should be no further episodes of positional nystagmus. If the post-Epley DHT is still positive, the Epley maneuver can be repeated. If the second Epley maneuver is unsuccess ful, instruct the patient to perform subsequent trials of the maneuver at home twice a day until symptoms resolve. Such patients should have follow-up to ensure clinical improvement. Since the episodes of BPPV typically last 15 to 30 seconds, do not prescribe vestibular suppressants. If the DHT is negative on both sides or purely horizontal nystagmus is seen, then perform the supine roll test to determine whether the patient is suffering from a less common variant of BPPV—horizontal canal BPPV .  TREATMENT OF HORIZONTAL CANAL BPPV If the patient has pure horizontal nystagmus when testing both left and right sides with the supine roll test, then the patient has horizontal canal BPPV and will not benefit from the Epley maneuver. Such patients can be treated with another particle repositioning maneuver called the Gufoni maneuver (See Video: Horizontal Canal BPPV). Horizontal canal BPPV is rarer, resolves spontaneously more quickly, and is more difficult to assess and treat than posterior canal BPPV . Thus, it is reasonable to refer the patient with suspected horizontal canal BPPV to a clinician familiar with the diagnosis for further management.

ee Video: Horizontal Canal BPPV). Horizontal canal BPPV is rarer, resolves spontaneously more quickly, and is more difficult to assess and treat than posterior canal BPPV . Thus, it is reasonable to refer the patient with suspected horizontal canal BPPV to a clinician familiar with the diagnosis for further management. Neurologic symptoms and/or deficits are or were present (see below*) Significant headache or neck pain Unable to stand unaided Short episodes (less than 2 minutes) initiated by head movement No ongoing, continuous vertigo Spontaneous or gaze evoked nystagmus Absent Many hours/days of ongoing, continuous vertigo, worsened by head movement Spontaneous or gaze evoked nystagmus Present Dix-Hallpike testing (HINTS plus not indicated) Vertical upward and rotatory nystagmus (= + Dix-Hallpike) BPPV Consider other diagnoses** Epley maneuver Negative Dix-Hallpike or atypical response HINTS plus testing (Dix-Hallpike not indicated) HINTS plus =central Stroke HINTS plus =peripheral Vestibular neuritis Any of: Bidirectional nystagmus Vertical skew deviation Normal HIT New hearing loss All four of: Unidirectional nystagmus No vertical skew deviation Abnormal HIT No new hearing loss Imaging indicated +/– referral to specialist care **Perform supine roll test to assess for Horizontal Canal BPPV No No Yes *Neurologic symptoms or deficits indicative of a central vertigo: Focal weakness or paresthesia of face or limbs Dysarthria, diplopia, dysphagia, dysmetria, dysphonia Spontaneous vertical nystagmus (not during Dix-Hallpike test) FIGURE 170-2. Flow chart of the initial approach to the diagnosis of acute vertigo. BPPV = benign paroxysmal positional vertigo; HINTS = head impulse test, nystagmus, test of skew; HIT = head impulse test. Tintinalli_Sec14_p1101-1186.indd 1148 8/2/19 12:08 PM

pontaneous vertical nystagmus (not during Dix-Hallpike test) FIGURE 170-2. Flow chart of the initial approach to the diagnosis of acute vertigo. BPPV = benign paroxysmal positional vertigo; HINTS = head impulse test, nystagmus, test of skew; HIT = head impulse test. Tintinalli_Sec14_p1101-1186.indd 1148 8/2/19 12:08 PM CHAPTER 170: Vertigo 1149 FIGURE 170-3. Left-sided Epley maneuver. A B C D  ANTERIOR CANAL BPPV Should the patient experience downward vertical nystagmus during the DHT, the patient may be suffering from the least common form of BPPV , anterior canal BPPV . It can be treated using the deep head hanging maneuver (See Video: Anterior Canal BPPV). Patients with a positive DHT are invariably suffering from posterior canal BPPV and do not need imaging. Rarely, patients with purely horizontal or down-beating nystagmus on positional testing may have a central cause of vertigo such as cerebellar degeneration, strokes, or tumors. If the appropriately selected maneuver fails to resolve the episode of BPPV , the patient should have follow-up for further assessment and treatment. BEDSIDE HINT+ TESTING TO DISTINGIUISH VESTIBULAR NEURITIS FROM CEREBELLAR/ BRAINSTEM STROKE  PERSISTENT CONTINUOUS ONGOING VERTIGO FOR HOURS OR DAYS WITH SPONTANEOUS NYSTAGMUS AND/OR GAZE-EVOKED NYSTAGMUS These patients are suffering from acute vestibular syndrome with ver tigo, nausea, and vomiting. Symptoms of acute vestibular syndrome worsen with head movement. Patients may also present with difficulty with gait. The majority of patients seen with acute vestibular syndrome are suffering from vestibular neuritis, but some will have a cerebellar stroke. Many, but not all, patients with stroke will have features sugges tive of central vertigo (Figure 170-2). If these features are present, the patient should have neurodiagnostic imaging. Less commonly, multiple sclerosis can also present with acute vestibular syndrome. HINTS Exam and HINTS Plus Exam The HINTS plus exam is a series of four bedside tests: head impulse test, nystagmus, and test of skew, plus a bedside test for new hearing loss. This battery of tests is used to distinguish patients with continuous vertigo (lasting hours to days) and nystagmus who have a peripheral disorder (most likely vestibular neuritis) from those who have a central disorder (most likely cerebellar stroke). The original HINTS study selected patients with at least two risk factors for stroke, and the majority had strokes. The HINTS exam was performed by a single neuro-ophthalmologist. The HINTS exam was more sensitive and specific than early MRI. A study of acute vestibular syndrome patients (two thirds of whom had vestibular neuritis) who had HINTS performed in the ED by neu rology residents showed almost identical results, with 100% sensitivity and 94% specificity for the HINTS exam in identifying stroke from vestibular neuritis. 10 (See Video: The HINTS Plus Exam in Vertigo.) Nystagmus Examine the patient first for spontaneous or gaze-evoked nystagmus and note the direction and type. Only patients with per sistent ongoing vertigo and spontaneous or gaze-evoked nystagmus should undergo HINTS testing. 7 In vestibular neuritis, the nystagmus (typically horizontal with a rotatory component) becomes more intense when the patient gazes in the direction of the nystagmus and lessens when looking away from the direction of the nystagmus. The affected ear in vestibular neuritis is the ear opposite to the direction of the nystagmus. Note that in vestibular neuritis, the fast component of the nystagmus does not change direction when gazing left and right. In central causes of nystagmus, the direction of the nystagmus may change direction depending on the direction of gaze (bidirectional nystagmus).

he ear opposite to the direction of the nystagmus. Note that in vestibular neuritis, the fast component of the nystagmus does not change direction when gazing left and right. In central causes of nystagmus, the direction of the nystagmus may change direction depending on the direction of gaze (bidirectional nystagmus). When the patient looks to the left, the fast component of the nystagmus is to the left, and when looking to the right, the fast component is to the right. Although this is not always seen in central causes of vertigo, it is a highly specific sign for central vertigo. Tintinalli_Sec14_p1101-1186.indd 1149 8/2/19 12:09 PM

When the patient looks to the left, the fast component of the nystagmus is to the left, and when looking to the right, the fast component is to the right. Although this is not always seen in central causes of vertigo, it is a highly specific sign for central vertigo. Tintinalli_Sec14_p1101-1186.indd 1149 8/2/19 12:09 PM 1150 SECTION 14: Neurology Test of Skew Test of skew is accomplished by the cover-uncover test. While the patient looks at the examiner’s nose, the examiner covers one eye and then covers the other eye. Any vertical or diagonally upward or downward movement of the eyes as they are uncovered indicates a central cause of vertigo. Head Impulse Test Next, the head impulse test is used to demonstrate an abnormal vestibulo-ocular reflex on the side of the affected ear, a finding in patients with vestibular neuritis. To perform a head impulse test, hold the patient’s head gently but firmly. Ask the patient to look at the examiner’s nose, and gently move the head left and right around 20 degrees from the midline. The patient should be sufficiently relaxed so that the examiner can then move the patient’s head from 20 degrees left or right of the midline quickly back to the midline. This should be done in a random fashion so that the patient does not anticipate in which direction the quick movement will occur. In normal subjects, the eyes remain fixated on the examiner’s nose, indicating an intact vestibulo-ocular reflex. In patients with vestibu lar neuritis, when the head is moved quickly toward the affected ear (spontaneous nystagmus is in the direction of the unaffected ear), the eyes will move with the head and thus overshoot the target (the examiner’s nose). The examiner sees a “catch up saccade” in the same direction as the spontaneous nystagmus that is noticeably larger in amplitude. Since most patients with stroke do not have a nerve deficit, a normal head impulse test is concerning for a central cause of vertigo in patients with persistent vertigo and spontaneous nystagmus. This counterintui tive finding bears emphasis, as it is open to misinterpretation. Hints Plus Finally, the “plus” component of the HINTS plus exam has the examiner check for acute hearing loss by rubbing thumb and fingers together just lateral to the patient’s left and right ear and ask ing whether the patient can hear it. New hearing loss is suggestive of a central cause. In particular, patients with an anterior inferior cerebellar artery stroke may have an abnormal head impulse test due to infarction of the labyrinth, as well as part of the cerebellum. The labyrinth contains the sensory end organs of balance and hearing. Thus, these patients will have both an abnormal head impulse test and new hearing loss. Table 170-2 outlines the clinical characteristics of BPPV , vestibular neuritis, and cerebellar stroke and details the indications for and inter pretation of DHT and HINTS plus testing.  TREATMENT OF VESTIBULAR NEURITIS The majority of patients with constant vertigo lasting hours to days who undergo HINTS plus testing in the ED will be diagnosed with vestibular neuritis. The treatment is largely symptomatic, with short courses of antiemetic medications to ease vomiting.  TREATMENT OF CEREBELLAR/BRAINSTEM STROKE Admission is indicated to allow monitoring for complications such as cerebral edema and hydrocephalus. Secondary stroke prevention and rehabilitation should also be instituted during hospitalization. It should be emphasized that the DHT should be performed only on patients with brief episodes of vertigo who have no spontaneous or gazeevoked nystagmus. HINTS plus testing should be performed only on patients with hours or days of continuous constant vertigo and who have nystagmus.

e instituted during hospitalization. It should be emphasized that the DHT should be performed only on patients with brief episodes of vertigo who have no spontaneous or gazeevoked nystagmus. HINTS plus testing should be performed only on patients with hours or days of continuous constant vertigo and who have nystagmus. Since the two clinical presentations are easy to distinguish, there is no rationale for performing both the DHT and the HINTS plus exam in the same patient. Patients who have vertigo that lasts between 2 minutes and many hours could have other diagnoses, most commonly vestibular migraine, Ménière’s syndrome, or transient ischemic attack.  POSTERIOR CIRCULATION TRANSIENT ISCHEMIC ATTACK Posterior circulation transient ischemic attack may present with tran sient vertigo and focal neurologic symptoms typical of cerebellar or brainstem stroke, such as weakness of the face or limbs, sensory changes, dysmetria (limb or truncal), diplopia, dysarthria, dysphagia, or dysphonia. Such patients should be triaged, investigated, and treated similar to patients with anterior circulation transient ischemic attacks. Since HINTS plus testing should be performed only on patients with ongo ing vertigo and nystagmus, HINTS plus testing is not appropriate for transient ischemic attack patients whose vertigo and/or other posterior circulation symptoms have resolved. Patients with posterior circulation stroke often experience transient neurologic attacks prior to the stroke. However, only 4% of patients with posterior circulation stroke seek medical attention for what seems to them to be nonspecific symptoms. 12 In one study of 169 patients with isolated vertigo, just one patient had a transient ischemic attack. 13 A study of 3900 patients with transient ischemic attack found that isolated vertigo was negatively associated with having an impending stroke. TABLE 170-2 Clinical Presentation and Guide to Bedside Testing for BPPV, Vestibular Neuritis, and Cerebellar Stroke BPPV Vestibular Neuritis Cerebellar Stroke Vertigo when still No Yes Yes Able to stand unaided Yes Yes May not be able to Spontaneous and/or gaze-evoked nystagmus No Yes Yes Typical spontaneous or gaze-evoked nystagmus seen Not present Unidirectional horizontal/rotatory Not purely vertical Various, including bidirectional horizontal/rotatory, sometimes vertical Worse when moves head Yes Yes Yes Other neurologic symptoms or findings No No Often but not always present New hearing loss No No Can occur Appropriate to perform Dix-Hallpike test Yes No No Nystagmus produced during Dix-Hallpike test Vertical upward and rotatory Do not perform Dix-Hallpike test Do not perform Dix-Hallpike test Appropriate to perform HINTS plus exam No Yes Yes Results from HINTS plus exam Do not perform HINTS plus testing All four findings: Unidirectional nystagmus No vertical skew Abnormal HIT No hearing loss HINTS plus = peripheral ANY of: Bidirectional nystagmus Vertical skew present Normal HIT New hearing loss HINTS plus = central Imaging indicated No No Yes Primary treatment Epley maneuver Supportive treatment Treatment for stroke Abbreviations: BPPV = benign paroxysmal positional vertigo; HINTS = head impulse test, nystagmus, test of skew; HIT = head impulse test. Tintinalli_Sec14_p1101-1186.indd 1150 8/2/19 12:09 PM

loss HINTS plus = central Imaging indicated No No Yes Primary treatment Epley maneuver Supportive treatment Treatment for stroke Abbreviations: BPPV = benign paroxysmal positional vertigo; HINTS = head impulse test, nystagmus, test of skew; HIT = head impulse test. Tintinalli_Sec14_p1101-1186.indd 1150 8/2/19 12:09 PM CHAPTER 170: Vertigo 1151 The optimal diagnostic approach for patients who present with sponta neous transient isolated vertigo remains uncertain. DIAGNOSTIC IMAGING See Table 170-3 for a condition-specific approach to diagnostic imaging. TREATMENT  SYMPTOMATIC TREATMENT FOR PERIPHERAL VERTIGO Short-term treatment with antiemetic and vestibular suppressant phar macotherapy is a mainstay for patients with peripheral vertigo other than BPPV15 (Table 170-4). Withdraw symptomatic treatments as soon as possible to facilitate central vestibular compensation.16  DRUG THERAPY Pharmacotherapy is used to treat specific conditions, reduce symptoms, or enhance vestibular compensation. Drugs with anticholinergic effects can be quite effective for vertigo. Transdermal scopolamine is a timehonored remedy. H 1 antihistamines are commonly prescribed drugs for their anticholinergic effects. H2 antihistamines are not effective. Calcium channel blockers (Table 170-4) are indicated for the symptomatic relief of vertigo in patients not responding to scopolamine or antihistamines. Neuroleptics such as promethazine and metoclopramide reduce nausea and vomiting by blocking brainstem dopaminergic receptors. They too are indicated as second-line treatment. Do not use prochlorperazine and chlorpromazine in dizziness caused by orthostatic hypotension. Ondansetron, a serotonin 5-HT 3 receptor antagonist, is an antinauseant that has been used to treat intractable vertigo in brainstem disorders as well as vertigo due to multiple sclerosis. Small doses of benzodiazepines may be used sparingly to relieve symptoms of acute vestibular neuritis. However, these agents may impair vestibular compensation and thus should not be used for more than 3 days. Betahistine is a strong H 3 and weak H 1 antagonist that increases cochlear blood flow and decreases peripheral vestibular inputs. A dos age of 48 milligrams/d is effective in treating vertigo, and may facilitate vestibular compensation. Gabapentin is indicated for dizziness associated with multiple sclerosis. Antihistamines can cause sedation and anticholinergic adverse effects. Antidopaminergic neuroleptic agents can induce or exacerbate orthostatic hypotension. These drugs also cause somnolence and acute dystonia and can exacerbate anticholinergic adverse effects. Avoid using medications with overlapping anticholinergic and antidopaminergic effects in combination. Do not treat patients with nonvertiginous dizziness and disequilibrium of aging with antivertigo medications. OTHER SPECIFIC CONDITIONS  VESTIBULAR MIGRAINE Vestibular migraine is the most common central cause of vertigo. After BPPV , it is the second most frequent cause of vertigo in the ED. It has a 1-year prevalence of 0.89%. 18 In patients who are referred to a tertiary vertigo clinic, 25% of the patients have vestibular migraine, but the diagnosis was suspected by the referring physician in less than 10% of cases. Vestibular migraine is a common cause of vertigo in children. For some postmenopausal women with a long-standing history of migraine, episodic vertigo may replace the typical headache. Thirty percent of patients have no headache before, during, or after the episode of vertigo. The diagnosis of vestibular migraine is made clinically (Table 170-5). Currently, there is no proven specific therapy for prophylaxis of vestibular migraine. 20 Expert opinion suggests the use of the medications that are commonly used for migraine headache.

e no headache before, during, or after the episode of vertigo. The diagnosis of vestibular migraine is made clinically (Table 170-5). Currently, there is no proven specific therapy for prophylaxis of vestibular migraine. 20 Expert opinion suggests the use of the medications that are commonly used for migraine headache.  MÉNIÈRE’S SYNDROME Ménière’s syndrome is a disorder associated with an increased endo lymph within the cochlea and labyrinth. It tends to occur in older men and women with equal prevalence. The disease is usually unilateral but may become bilateral over time. The precise pathogenesis is unknown, but evidence suggests that patients have difficulty regulating the volume, flow, and composition of endolymph. The onset is usually sudden, with associated nausea, vomiting, and diaphoresis, with attacks lasting from 20 minutes to 12 hours. The frequency of attacks varies from several times per week to several times per month. Other associated symptoms include tinnitus, diminished hearing, and fullness in one ear. Between attacks, the patient is usually well, although decreased hearing may persist. Ménière’s syndrome is managed symptomatically with antihistamines and betahistine; combination therapy with triamterene and hydrochlo rothiazide is also recommended in confirmed cases. Calcium channel blockers may also be used (Table 170-4). None of these drug treatments improves hearing. Refer patients for treatment to an otolaryngologist, because intratympanic injections of corticosteroids or gentamicin are increasingly used to control the frequency of attacks in patients not responding to standard therapy.  PERILYMPH FISTULA A perilymph fistula is an opening in the round or oval window that permits pneumatic changes in the middle ear to be transmitted to the vestibular apparatus. Trauma, infection, or a sudden change in the pressure inside the ventricular system may cause the tear. The diagnosis is suggested by the sudden onset of vertigo and hearing loss associated with head trauma, flying, scuba diving, severe straining, heavy lifting, coughing, or sneezing. Associated symptoms may include hearing loss. Perilymph fistula is managed with symptomatic treatment and bed rest and referral to an ear, nose, and throat specialist for surgical repair (emergent referral for patients with acute associated hearing loss).  VESTIBULAR GANGLIONITIS Vestibular ganglionitis is believed to be caused by a neurotrophic virus such as varicella-zoster reactivated years following initial infection.

bed rest and referral to an ear, nose, and throat specialist for surgical repair (emergent referral for patients with acute associated hearing loss).  VESTIBULAR GANGLIONITIS Vestibular ganglionitis is believed to be caused by a neurotrophic virus such as varicella-zoster reactivated years following initial infection. Herpes zoster oticus, also known as the Ramsay Hunt syndrome, is a TABLE 170-3 Approach to Diagnostic Imaging in Vertigo BPPV and vestibular neuritis: none required if findings are typical and bedside testing is confirmatory Cerebellar/brainstem stroke: •   CT angiography if in rare case the stroke score deficit indicates potential benefit for thrombolysis or endovascular clot retrieval •   Emergent MRI if acute intervention not indicated or HINTS plus indicates central cause and more than 48 hours of vertigo •   Admit to hospital and perform delayed MRI in 2–3 days if acute intervention  not indicated; HINTS plus indicates central cause and symptoms less than 48 hours Vestibular migraine: none required if clinical history and presentation are diagnostic for vestibular migraine Suspected vertebral artery dissection (significant ongoing neck pain): CT angiography or MRI/MRA of head and neck TIA with neurologic symptoms or signs beyond vertigo and nystagmus: CT angiography or MRI/MRA Suspected TIA without neurologic symptoms (isolated vertigo): consider CT angiography or MRA if patient has significant risk factors for stroke/TIA; a optimal diagnostic strategy has yet to be defined Ménière’s disease: none for typical presentation Suspected cerebellar hemorrhage (significant ongoing headache or decreased level of consciousness): CT of the head Multiple sclerosis: MRI Postconcussive vertigo: CT of the head if intracranial hemorrhage suspected Labyrinthitis: •   Viral: none •   Bacterial: MRI Superior canal dehiscence syndrome: CT of temporal bone Vestibular schwannomas: MRI Abbreviations: BPPV = benign paroxysmal positional vertigo; HINTS = head impulse test, nystagmus, test of skew; MRA = magnetic resonance angiography; TIA = transient ischemic attack. Tintinalli_Sec14_p1101-1186.indd 1151 8/2/19 12:09 PM

Superior canal dehiscence syndrome: CT of temporal bone Vestibular schwannomas: MRI Abbreviations: BPPV = benign paroxysmal positional vertigo; HINTS = head impulse test, nystagmus, test of skew; MRA = magnetic resonance angiography; TIA = transient ischemic attack. Tintinalli_Sec14_p1101-1186.indd 1151 8/2/19 12:09 PM 1152 SECTION 14: Neurology neuropathic disorder thought to be associated with vestibular gangli onitis. It is characterized by deafness, vertigo, and facial nerve palsy. The diagnosis is confirmed by the presence of grouped vesicles on an erythematous base inside the external auditory canal. Treat this disorder with antiviral therapy started within 72 hours of the appearance of vesicles along with symptomatic treatments.  OTOTOXICITY Various drugs have been found to be ototoxic (Table 170-6). Aminoglycoside antibiotics produce hearing loss and peripheral vestibular dysfunction by accumulating inside the endolymph, causing the death of cochlear and vestibular hair cells. However, because both inner ears are affected, vertigo is uncommon. Clinical manifestations include ataxia and oscillopsia (defined as the inability to maintain visual fixation while moving). The damage is usually irreversible but is dose and duration dependent. Loop diuretics (furosemide and ethacrynic acid) also cause irreversible vestibular toxicity and ototoxicity. Cytotoxic agents such as vinblastine and cisplatin cause vestibular damage; however, newer platinums, such as carboplatin, are less likely to do so. The antiarrhythmic drug quinidine and antimalarial drugs derived from quinine, such as chloroquine and mefloquine, also can cause vestibular symptoms that may be irreversible. Reversible causes of vestibular damage and ototoxicity include NSAIDs, salicylates, minocycline, erythromycin, and some fluoroquinolones.

do so. The antiarrhythmic drug quinidine and antimalarial drugs derived from quinine, such as chloroquine and mefloquine, also can cause vestibular symptoms that may be irreversible. Reversible causes of vestibular damage and ototoxicity include NSAIDs, salicylates, minocycline, erythromycin, and some fluoroquinolones. TABLE 170-4 Pharmacotherapy of Vertigo and Dizziness Category Drug Dosage Indications Advantages Disadvantages Anticholinergics Scopolamine 0.5 milligram transdermal patch (behind ear) three to four times a day Vertigo, nausea Useful if patient is vomiting Sometimes difficult to obtain Antihistamines Dimenhydrinate 50–100 milligrams IM, IV, or PO every 4 h Vertigo, nausea Inexpensive Drowsiness/anticholinergic effect Diphenhydramine 25–50 milligrams IM, IV, or PO every 4 h Vertigo, nausea Inexpensive Drowsiness/anticholinergic effect Meclizine 25 milligrams PO two to four times a day Vertigo, nausea Drowsiness/anticholinergic effect Antiemetics Hydroxyzine 25–50 milligrams PO four times a day Vertigo, nausea Inexpensive Drowsiness/anticholinergic effect Metoclopramide 10–20 milligrams IV, PO three times a day Vertigo, nausea Effective, versatile Occasional extrapyramidal effect Ondansetron 4 milligrams IV two to three times a day; 8 milligrams PO twice a day Promethazine 25 milligrams IM, PO, or PR three to four times a day Vertigo, nausea Useful if vomiting Occasional extrapyramidal effect Benzodiazepines Diazepam 2–5 milligrams PO two to four times a day Central vertigo, anxiety related to peripheral vertigo Inexpensive Dependency, may impair vestibular compensation Clonazepam 0.5 milligram PO two times a day Central vertigo, anxiety related to peripheral vertigo Inexpensive Dependency, may impair vestibular compensation Calcium antagonists Cinnarizine 25 milligrams PO two to three times a day Peripheral vertigo, vestibular migraine Nonsedating Lesser clinical experience Nimodipine 30 milligrams PO two times a day Peripheral vertigo, vestibular migraine Nonsedating Lesser clinical experience Flunarizine 20 milligrams PO two times a day Ménière’s syndrome Well tolerated Not available in the United States Vasodilators Betahistine 48 milligrams PO three times a day for up to 6–12 mo Ménière’s syndrome Well tolerated Little evidence of efficacy for other causes of peripheral vertigo Corticosteroids Methylprednisolone 100 milligrams/d tapered by 20 milligrams/d every fourth day Vestibular neuronitis Well tolerated Efficacy largely unproven; adverse effects associated with corticosteroids Antivirals Valacyclovir 1000 milligrams three times a day for 7 d Vestibular neuronitis Well tolerated Efficacy largely unproven Anticonvulsants Carbamazepine 200–600 milligrams/d Vestibular paroxysmia Inexpensive Monitor CBC and liver function tests Topiramate 50–100 milligrams/d Vestibular migraine prophylaxis Well tolerated Not well evaluated; does not abort acute vertigo Valproic acid 300–900 milligrams/d Vestibular migraine prophylaxis Well tolerated Not well evaluated; does not abort acute vertigo Gabapentin 300 milligrams four times per day Multiple sclerosis–associated dizziness Reduces acquired pendular nystagmus of multiple sclerosis Known adverse effect profile β-Blockers Metoprolol 100 milligrams/d Vestibular migraine prophylaxis Long experience Known adverse effect profile TABLE 170-5 Diagnostic Criteria for Vestibular Migraine •  Moderate  or severe episodes of vertigo lasting 5 minutes to 72 hours •  Past  or current history of migraine •   5 or more episodes of vertigo , at least 50% of which have one of following three migrainous features: visual aura, photophobia or phonophobia, or typical migraine headaches •   Typical migraine headaches should have at least two of the following four qualities: unilateral, pulsating, moderate or severe i

migraine •   5 or more episodes of vertigo , at least 50% of which have one of following three migrainous features: visual aura, photophobia or phonophobia, or typical migraine headaches •   Typical migraine headaches should have at least two of the following four qualities: unilateral, pulsating, moderate or severe i ntensity, or aggravated by routine activity •   In addition, the patient’s clinical presentation should not better accounted for by another headache or vestibular problem Tintinalli_Sec14_p1101-1186.indd 1152 8/2/19 12:09 PM