Small strokes causing severe vertigo: frequency of false-negative MRIs and nonlacunar mechanisms

Time Course and Clinical Correlates of Retinal Diffusion Restrictions in Acute Central Retinal Artery Occlusion

BACKGROUND AND PURPOSE

Retinal diffusion restrictions were recently identified as a regular finding in acute central retinal artery occlusion. We sought to investigate the influence of technical MR imaging and clinical parameters on the detection rate of retinal diffusion restrictions on standard brain DWI.

MATERIALS AND METHODS

In this retrospective cohort study, MR imaging scans of patients with central retinal artery occlusion were assessed by 2 readers for retinal diffusion restrictions on DWI performed within 2 weeks after vision loss. The influence of clinical and technical MR imaging parameters and the time interval between symptom onset and DWI on the presence of retinal diffusion restrictions were evaluated.

RESULTS

One hundred twenty-seven patients (mean age, 69.6 [SD 13.9] years; 59 women) and 131 DWI scans were included. Overall, the MR imaging sensitivity of retinal diffusion restrictions in acute central retinal artery occlusion was 62.6%-67.2%. Interrater and intrarater agreement for retinal diffusion restrictions was "substantial" with κ_inter= 0.70 (95% CI, 0.57-0.83) and κ_intra= 0.75 (95% CI, 0.63-0.88). Detection of retinal diffusion restrictions did not differ with differences in field strengths (1.5 versus 3T, P = .35) or sequence type (P = .22). Retinal diffusion restrictions were consistently identified within the first week with a peak sensitivity of 79% in DWI performed within 24 hours after symptom onset. Sensitivity of retinal diffusion restrictions declined in the second week (10.0%, P < .001). Absence of retinal diffusion restrictions was more prevalent in patients without fundoscopic retinal edema (60% versus 27.1%, P = .004) and with restitution of visual acuity at discharge (75% versus 28.4%, P = .006).

CONCLUSIONS

Retinal diffusion restrictions in acute central retinal artery occlusion can be reliably identified on DWI performed within 24 hours and 1 week after onset of visual impairment. Detectability of retinal diffusion restrictions is dependent on the clinical course of the disease.

Just the Facts: How to assess a patient with constant significant vertigo and nystagmus in the emergency department

A 43-year-old female presents to the emergency department (ED) after she woke up with the sensation that the room was spinning and vomited three times at home. She continues to have significant vertigo when she presents to the ED 4 hours later. Her symptoms are worsened by head movement. She has noticed some unsteadiness but is able to walk unaided. When you examine her, she has left-beating horizontal nystagmus with a slight rotatory component to the left.

Acute Vestibular Syndrome and ER Presentations of Dizziness

Acute vestibular syndrome (AVS) describes sudden onset, severe, continuous dizziness that persists for more than 24 hours. Its wide differential presents a diagnostic challenge. Vestibular neuritis is the most common cause, but stroke, trauma, medication effects, infectious, and inflammatory causes all present similarly. The TiTrATE model (Timing, Triggers, And Targeted Exam) is systematic way to evaluate these patients, and the HINTS Plus exam (Head Impulse, Nystagmus, Test of Skew, plus hearing loss) is critical in differentiating central and peripheral causes. The importance of recognizing risk factors for stroke and the role of imaging is also discussed.

Diagnosing Stroke in Acute Vertigo: Sensitivity and Specificity of HINTS Battery in Indian Population

Introduction

Most patients presenting with acute vertigo are believed to suffer from acute, self-limited, presumed viral or post-viral vestibular neuritis (VN). But 25% of such cases can be "Pseudo VN", and are due to central causes, most often stroke. The aim of the present research was to study the sensitivity and specificity of Head Impulse, Nystagmus, Skew deviation (HINTS) battery for diagnosis of stroke in patients with acute-onset first episode of spontaneous vertigo.

Materials and Methods

Seventy-five patients who visited outpatient department or admitted between August 2014 and April 2016 with acute-onset first episode of spontaneous vertigo were included. Each patient was subjected to bedside oculomotor tests and HINTS. All patients underwent magnetic resonance imaging (MRI) of the brain. Stroke was diagnosed by MRI brain. If initial MRI brain was normal and still clinical signs favor stroke, repeat MRI brain-diffusion-weighted imaging study was done at 72 h after symptom onset to confirm the diagnosis. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy and Youden's Index were used to quantify the diagnostic efficiency of HINTS at presentation against final MRI.

Results

Patients presented with acute-onset first episode of spontaneous vertigo, HINTS battery was found to be more sensitive than the initial MRI of the brain done in first 24 h in diagnosing stroke (97.1 % Vs 82.9%). The specificity of the initial MRI of the brain and HINTS battery was 100.0 % and 80.0% respectively.

Conclusions

The HINTS battery was more sensitive than the initial MRI of the brain in diagnosing stroke in first 24 h in patients presented with acute-onset first episode of spontaneous vertigo.

Clinical Diagnosis of Central Vertigo in Patients With Dizziness in Emergency Practice

BACKGROUND

Life-threatening diseases should be promptly identified to provide appropriate medical care for emergency outpatients experiencing dizziness. However, dizziness is associated with various medical conditions; thus, a definitive diagnosis is challenging. To accurately diagnose vertigo in an emergency outpatient, we conducted a survey on the need to identify vertigo patients in the current outpatient departments.

MATERIALS AND METHODS

The participants included 509 patients who visited the outpatient department at our hospital from February 2014 to May 2017. Overall, 12 characteristics were retrospectively extracted from the patients' medical records: age, sex, visit method, medical history (diabetes, hypertension, cardiac, or cerebrovascular disease), dizziness history, vertigo characteristics, concomitant symptoms, systolic blood pressure, nystagmus, imaging history, diagnosis, and hospitalization department. Univariate and multivariate analyses were performed to identify factors related to central vertigo.

RESULTS

The diagnosis of central vertigo was confirmed when intracranial lesions were detected through imaging. In multivariate analysis, the presence/absence of a history of headache and cardiovascular disease were significantly correlated with central vertigo (P=0.002 and 0.006, respectively), with odds ratios of 5.18 and 4.38, respectively.

CONCLUSIONS

To avoid missing central dizziness in a patient, diagnostic abilities should be improved by including careful interviews and confirmation of the presence/absence of accompanying symptoms. Furthermore, collaboration with neurology and neurosurgery departments is important for improving the diagnosis in suspected cases.

[Update on diagnosis and therapy in frequent vestibular and balance disorders]

The 8 most frequent vestibular disorders account for more than 70% of all presentations of vertigo, dizziness, and imbalance. In acute (and mostly non-repetitive) vestibular disorders acute unilateral vestibulopathy and vestibular stroke are most important, in episodic vestibulopathies benign paroxysmal positional vertigo (BPPV), Menière's disease and vestibular migraine, and in chronic vestibular disorders bilateral vestibulopathy/presbyvestibulopathy, functional dizziness and cerebellar dizziness. In the last decade, internationally consented diagnostic criteria and nomenclature were established for the most frequent vestibular disorders, which can be easily applied in clinical practice. The diagnostic guidelines are based on history taking (including onset, duration, course, triggers, accomanying symptoms), clinical examination, and only a few apparative tests (by videooculography and audiometry) for securing the diagnosis. Treatment of vestibular disorders includes physical training (repositioning maneuvers, multimodal balance training) and pharmacological approaches (e.g., corticosteroids, antiepileptics, antidepressants, potassium-canal-blockers, drugs enhancing neuroplasticity). For most drugs, high-level evidence from prospective controlled trials is lacking. In clinical practice, the most frequent vestibular disorders can be treated effectively, thus avoiding chronicity and secondary comorbidity (by immobility, falls or psychiatric disorders such as anxiety or depression).

Acute Vestibular Syndrome

PURPOSE OF REVIEW

This article provides a practical approach to acute vestibular syndrome while highlighting recent research advances.

RECENT FINDINGS

Acute vestibular syndrome is defined as sudden-onset, continuous vertigo lasting longer than 24 hours with associated nausea and vomiting, all of which are worsened with head movement. Acute vestibular syndrome is provoked by a variety of central and peripheral causes, the most common of which are vestibular neuritis and acute stroke (posterior circulation). A clinical approach focusing on timing, associated history, and ocular motor findings can improve diagnostic accuracy and is more sensitive and specific than early neuroimaging. Because of the shared neurovascular supply, both peripheral and central vestibular disorders can manifest overlapping signs previously considered solely peripheral or central, including vertical skew, nystagmus, abnormal vestibular ocular reflex, hearing loss, and gait instability. Although acute vestibular syndrome is typically benign, stroke should be considered in every person with acute vestibular syndrome because it can act as a harbinger of stroke or impending cerebellar herniation. Treatment is focused on physical therapy because the evidence is minimal for the long-term use of medication.

SUMMARY

The diagnosis of acute vestibular syndrome first requires the elimination of common medical causes for dizziness. Next, underlying pathology must be determined by distinguishing between the most common causes of acute vestibular syndrome: central and peripheral vestibular disorders. Central vestibular disorders are most often the result of ischemic stroke affecting the cerebellar arteries. Peripheral vestibular disorders are assumed to be caused mostly by inflammatory sources, but ischemia of the peripheral vestibular apparatus may be underappreciated. By using the HINTS Plus (Head Impulse test, Nystagmus, Test of Skew with Plus referring to hearing loss assessment) examination in addition to a comprehensive neurologic examination, strokes are unlikely to be missed. For nearly all acute vestibular disorders, vestibular physical therapy contributes to recovery.

Stroke prediction in patients presenting with isolated dizziness in the emergency department

Diagnosing stroke in patients experiencing dizziness without neurological deficits is challenging for physicians. The aim of this study was to evaluate the prevalence of acute stroke in patients who presented with isolated dizziness without neurological deficits at the emergency department (ED), and determine the relevant stroke predictors in this population. This was an observational, retrospective record review of consecutive 2215 adult patients presenting with dizziness at the ED between August 2019 and February 2020. Multivariate analysis was performed to identify risk factors for acute stroke. 1239 patients were enrolled and analyzed. Acute stroke was identified in 55 of 1239 patients (4.5%); most cases (96.3%) presented as ischemic stroke with frequent involvement (29.1%) of the cerebellum. In the multivariate analysis, the history of cerebrovascular injury (odds ratio [OR] 3.08 [95% confidence interval {CI} 1.24 to 7.67]) and an age of > 65 years (OR 3.01 [95% CI 1.33 to 6.83]) were the independent risk factors for predicting acute stroke. The combination of these two risks showed a higher specificity (94.26%) than that of each factor alone. High-risk patients, such as those aged over 65 years or with a history of cerebrovascular injury, may require further neuroimaging workup in the ED to rule out stroke.

Limited usefulness of routine head and neck CT angiogram in the imaging assessment of dizziness in the emergency department

OBJECTIVE

To assess the usefulness of head and neck computed tomography angiogram for the investigation of isolated dizziness in the emergency department in detecting significant acute findings leading to a change in management in comparison to non-contrast computed tomography scan of the head.

METHODS

Patients presenting with isolated dizziness in the emergency department investigated with non-contrast computed tomography and computed tomography angiogram over the span of 36 months were included. Findings on non-contrast computed tomography were classified as related to the emergency department presentation versus unrelated/no significant abnormality. Similarly, computed tomography angiogram scans were classified as positive or negative posterior circulation findings.

RESULTS

One hundred and fifty-three patients were imaged as a result of emergency department presentation with isolated dizziness. Fourteen cases were diagnosed clinically as of central aetiology. Non-contrast computed tomography was positive in three patients, all with central causes with sensitivity 21.4%, specificity 100%, positive predictive value 100%, negative predictive value 92.6% and accuracy 92.8%. Computed tomography angiogram was positive for angiographic posterior circulation abnormalities in five cases, and only two of them had a central cause of dizziness, with sensitivity 14.3%, specificity 97.7%, positive predictive value 40%, negative predictive value 91.46% and accuracy 92.1%.

CONCLUSION

Both non-contrast computed tomography and computed tomography angiogram of the head and neck have low diagnostic yield for the detection of central causes of dizziness, However, non-contrast computed tomography has higher sensitivity and positive predictive value than computed tomography angiogram, implying a lack of diagnostic advantage from the routine use of computed tomography angiogram in the emergency department for the investigation of isolated dizziness. Further studies are required to determine the role of computed tomography angiogram in the work-up of isolated dizziness in the emergency department.

Vertigo and dizziness in the emergency room

PURPOSE OF REVIEW

To provide an update on diagnostic algorithms for differential diagnosis of acute vertigo and dizziness and swift identification of potentially harmful causes.

RECENT FINDINGS

About 25% of patients with acute vertigo and dizziness have a potentially life-threatening diagnosis, including stroke in 4-15%. Diagnostic work-up relies on the combination of symptom features (triggers, duration, history of vertigo/dizziness, accompanying symptoms) and a comprehensive vestibular, ocular motor, and balance exam. The latter includes head impulse, head-shaking nystagmus, positional nystagmus, gaze-holding, smooth pursuit, skew deviation, and Romberg's test. Recent standardized diagnostic algorithms (e.g., HINTS, TriAGe+) suggest the combination of several elements to achieve a good diagnostic accuracy in differentiation of central and peripheral vestibular causes. Neuroimaging with MRI must be applied and interpreted with caution, as small strokes are frequently overlooked, especially in the acute setting (false-negative rate of up to 50%).

SUMMARY

Diagnostic differentiation of acute vertigo and dizziness remains a complex task, which can be tackled by a structured clinical assessment focusing on symptom characteristics and constellations of ocular motor and vestibular findings. Specific challenges arise in cases of transient or atypical vestibular syndromes.

Usability of the head impulse test in routine clinical practice in the emergency department to differentiate vestibular neuritis from stroke

BACKGROUND AND PURPOSE

The bedside head impulse test (bHIT) is used to differentiate vestibular neuritis (VN) from posterior circulation stroke (PCS) in patients presenting with acute vestibular syndrome (AVS). If assessed by neuro-otological experts, diagnostic accuracy is high. We report on its diagnostic accuracy when applied by nonexperts during routine clinical practice in the emergency department (ED), its impact on patient management, and the potential diagnostic yield of the video-oculography-supported head impulse test (vHIT).

METHODS

Medical chart review of 38 AVS patients presenting to our university medical center's ED, assessed by neurology residents. We collected bHIT results (abnormal/peripheral or normal/central) and whether patients were admitted to the stroke unit or general neurological ward. Final diagnosis (VN, n = 24; PCS, n = 14) was determined by clinical course, magnetic resonance imaging, and vHIT.

RESULTS

The bHIT's accuracy was only 58%. Its sensitivity for VN was high (88%), but due to many false-abnormal bHITs in PCS (36%), the specificity was low (64%). The vHIT yielded excellent specificity (100%) and moderate sensitivity (67%). The decision on the patient's further care was almost arbitrary and independent from the bHIT: 58% of VN and 57% of PCS patients were admitted to the stroke unit.

CONCLUSIONS

The bHIT, applied by nonexperts during routine practice in the ED, has low accuracy, is too often mistaken as abnormal/peripheral, and is not consistently used for patients' in-hospital triage. As false-abnormal bHITs can lead to misdiagnosis/mistreatment of stroke patients, we recommend that bHIT applied by nonexperts should be reassessed by a neuro-otological expert or preferably quantitative vHIT in the ED.

Modern machine-learning can support diagnostic differentiation of central and peripheral acute vestibular disorders

BACKGROUND

Diagnostic classification of central vs. peripheral etiologies in acute vestibular disorders remains a challenge in the emergency setting. Novel machine-learning methods may help to support diagnostic decisions. In the current study, we tested the performance of standard and machine-learning approaches in the classification of consecutive patients with acute central or peripheral vestibular disorders.

METHODS

40 Patients with vestibular stroke (19 with and 21 without acute vestibular syndrome (AVS), defined by the presence of spontaneous nystagmus) and 68 patients with peripheral AVS due to vestibular neuritis were recruited in the emergency department, in the context of the prospective EMVERT trial (EMergency VERTigo). All patients received a standardized neuro-otological examination including videooculography and posturography in the acute symptomatic stage and an MRI within 7 days after symptom onset. Diagnostic performance of state-of-the-art scores, such as HINTS (Head Impulse, gaze-evoked Nystagmus, Test of Skew) and ABCD2 (Age, Blood, Clinical features, Duration, Diabetes), for the differentiation of vestibular stroke vs. peripheral AVS was compared to various machine-learning approaches: (i) linear logistic regression (LR), (ii) non-linear random forest (RF), (iii) artificial neural network, and (iv) geometric deep learning (Single/MultiGMC). A prospective classification was simulated by ten-fold cross-validation. We analyzed whether machine-estimated feature importances correlate with clinical experience.

RESULTS

Machine-learning methods (e.g., MultiGMC) outperform univariate scores, such as HINTS or ABCD2, for differentiation of all vestibular strokes vs. peripheral AVS (MultiGMC area-under-the-curve (AUC): 0.96 vs. HINTS/ABCD2 AUC: 0.71/0.58). HINTS performed similarly to MultiGMC for vestibular stroke with AVS (AUC: 0.86), but more poorly for vestibular stroke without AVS (AUC: 0.54). Machine-learning models learn to put different weights on particular features, each of which is relevant from a clinical viewpoint. Established non-linear machine-learning methods like RF and linear methods like LR are less powerful classification models (AUC: 0.89 vs. 0.62).

CONCLUSIONS

Established clinical scores (such as HINTS) provide a valuable baseline assessment for stroke detection in acute vestibular syndromes. In addition, machine-learning methods may have the potential to increase sensitivity and selectivity in the establishment of a correct diagnosis.

Differential Diagnosis of Ischemic Vertigo by Optical Coherence Tomography

Objective

This study aimed to evaluate the differences in the mean retinal nerve fiber layer (RNFL) thickness using optical coherence tomography (OCT) in patients with early stage central vertigo with or without vertebrobasilar stenosis detected by Doppler ultrasound.

Materials and Methods

A total of 50 patients with ischemic vertigo and 50 healthy individuals were included in the study. The distinction between central and peripheral vertigo was determined by physical and neurological examinations and the Dix-Hallpike maneuver. For all patients, the mean RNFL thickness was determined using OCT performed by 2 independent ophthalmologists.

Results

There were no significant differences between the groups in terms of age and sex distribution (p>0.05). On average, in superior, inferior, and temporal quadrants, there was a statistically significant difference between the control and patient groups (p<0.001).

Conclusion

The retina may be affected in patients with ischemic vertigo because of atherosclerotic ischemic lesions in the carotid and vertebral arteries. Neuroimaging methods and OCT were evaluated together to develop a new diagnostic approach. With OCT, which is a non-invasive method, early and more objective differential diagnosis will be possible.

False-Negative Initial Magnetic Resonance Imaging in Acute Posterior Circulation Stroke: A Case Report Describing Locked-in Syndrome

Locked-in syndrome is defined as quadriplegia and anarthria with the preservation of consciousness. Typically, locked-in syndrome is caused by an insult to the ventral pons secondary to trauma or vascular disease. Presented herein is a case of a locked-in syndrome with an initial MRI with no restricted diffusion and clinical deterioration over the course of four days. Repeat interval MRI demonstrated bilateral pontine ischemia.

Diagnosis of Patients with Acute Dizziness

Using an algorithmic approach to acutely dizzy patients, physicians can often confidently make a specific diagnosis that leads to correct treatment and should reduce the misdiagnosis of cerebrovascular events. Emergency clinicians should try to become familiar with an approach that exploits timing and triggers as well as some basic "rules" of nystagmus. The gait should always be tested in all patients who might be discharged. Computed tomographic scans are unreliable to exclude posterior circulation stroke presenting as dizziness, and early MRI (within the first 72 hours) also misses 10% to 20% of these cases.

[Dizziness and vertigo in a tertiary ENT emergency department]

BACKGROUND

Although vestibular symptoms are amongst the most frequent reasons for seeking emergency medical help, many patients remain undiagnosed.

OBJECTIVE

In this cross-sectional study, we investigated the spectrum of vertigo and dizziness in a tertiary ear, nose, and throat (ENT) emergency department (ED). Furthermore, we investigated the attendant symptoms, clinical signs, and the diagnostic tests performed.

METHODS

We screened all ED reports from 01/2013 to 12/2013 for adult patients with vestibular symptoms referred to the ENT department.

RESULTS

In total, we found 2596 cases with reported vestibular symptoms in the ED as a main or accompanying complaint. Of these, 286 were referred to the ENT specialist directly (n = 98) or via other major medical specialties (n = 188). Benign paroxysmal positional vertigo (BPPV) was the most frequent diagnosis in our study (n = 46, 16.1%), followed by vestibular neuritis (n = 44, 15.4%), otitis media (n = 20, 7%), and 9 patients (3.1%) had an ischemic stroke or a transient ischemic attack. In 70 (24.5%) cases, dizziness was not further specified.

CONCLUSION

BPPV is the most frequent diagnosis seen in the ED; however, physicians need to document nystagmus more precisely and perform diagnostic tests systematically, in order to make an accurate diagnosis. To avoid misdiagnoses, ED physicians and ENT specialists should be able to recognize central signs in patients with an acute vestibular syndrome. Every fourth patient does not receive a definitive diagnosis. Diagnostic ED workup for patients with dizziness needs further improvement.

Characteristics and resource needs in patients with vestibular symptoms: a comparison of patients with symptoms of unknown versus determined origin

BACKGROUND

Vestibular symptoms are a frequent reason for presenting at the emergency department (ED). Underlying conditions range in severity from life-threatening to benign, but often remain undiagnosed despite extensive investigations. We aimed to identify clinical characteristics that are associated with ED consultations by patients with vestibular symptoms of unknown origin (VUO) and to quantify the ED resources consumed during the investigations.

METHODS

This retrospective one-year, single-centre, cross-sectional study assessed ED consultations with patients whose chief complaint was 'vestibular symptoms'. Data on risk factors, clinical characteristics, management and ED resources were extracted from the administrative database and medical records. Consultations were grouped according to the discharge diagnosis as either VUO or non-VUO. We determined clinical factors associated with VUO and compared ED resource consumption by the two patient groups using multivariable analysis.

RESULTS

A total of 1599 ED consultations were eligible. Of these, 14.3% (n = 229) were consultations with patients with VUO. Clinical characteristics included in the final multivariable model to determine associations with VUO were sensory disorders, aural fullness, improvement at rest, absence of situational provocation, pre-existing neurological conditions, and age < 65 years. Patients with VUO had higher total ED resource consumption in terms of physicians' work and radiology resources, as a result of more use of computed tomography and magnetic resonance imaging.

CONCLUSION

One in seven emergency patients with vestibular symptoms is dismissed without a diagnosis. Clinical characteristics of VUO patients are distinct from patients in whom a diagnosis was made in the ED. VUO triggers higher ED resource consumption, which can be justified if appropriately indicated.

Predictors of vertigo in the emergency department: The preved study

BACKGROUND AND PURPOSE

Acute vertigo (sense of motion) can be the sole manifestation of a posterior circulation stroke, and often gets missed in the emergency department (ED). The studies for evaluation of central vertigo have focused on physical exam findings, which require expertise and may not be suitable for rapid triage by a nurse in ED or by paramedics.

METHODS

This cross sectional study included retrospective chart review of patients 18 years of age and older who presented to the Adult ED with acute dizziness or vertigo during the calendar year 2017. All the patients with a diagnosis of central or peripheral vertigo were included in the final analysis. Sensitivity, specificity, Likelihood Ratio of positive result (LR (+)) and Likelihood Ratio of negative result (LR (-)) for central and peripheral vertigo were calculated for risk factors, symptoms and physical examination features. Chi-squared test and univariate logistic regression were used to evaluate statistical correlation and to calculate the prevalence odds ratio (POR).

RESULTS

Two hundred and forty nine out of 505 (49.3%) patients presenting with dizziness had vertigo. Of these, 14 had central vertigo and 163 had peripheral vertigo. Statistically significant variables were: constant symptoms of vertigo (p 0.000- POR 8.7, 95% confidence interval (CI) 2.3-33.1), no change in symptoms with head movement (p 0.000- POR 10.2, 95% CI 3.0-35.4), dysmetria (p 0.000- POR 56.8, 95% CI 5.8-557.1), and unsteady gait (p 0.000- POR 13.3, 95% CI 3.3-54.3). The sensitivity and specificity to detect central vertigo were 100% and 66.4% respectively if the patient had either unsteady gait, constant symptoms, or no change in symptoms with head movement, [VAIN triad (Vertigo- Ataxia, Incessant, or Non-positional)].

CONCLUSIONS

We suggest that triage with VAIN triad can be used to design prospective studies to develop a triage algorithm for the detection of central vertigo in the ED.

Acute binocular diplopia: peripheral or central?

Objectives

Acute diplopia is a diagnostic challenge for clinicians, in particular in the emergency department. The most common cause of acute diplopia are ocular motor nerve palsies (OMP). In this prospective study, we focused on identifying the most crucial signs and symptoms for differentiating between peripheral and central OMP.

Methods

We prospectively evaluated 56 non-consecutive patients who presented at our emergency department with acute binocular diplopia (≤ 10 days). The patient history was taken using a standardized questionnaire and patients underwent a neurological, neuro-ophthalmological and neuro-otological examination, including measurement of the subjective visual vertical (SVV), Harms tangent screen test, and cranial MRI.

Results

Forty-six out of 56 patients were diagnosed with an ocular motor cranial nerve palsy (OMP), 21 of peripheral and 23 of central origin; in two patients, the etiology remained unknown. The following features were different in peripheral and central OMP: (1) the presence of vertigo/dizziness was more frequent in central (43.5%) than in peripheral (9.5%) OMP. (2) Central ocular motor signs, such as saccadic smooth pursuit, additional internuclear ophthalmoplegia, skew deviation, and saccade palsies, were also found more frequently in the central than in the peripheral group (86.7% vs. 33.3%). (3) Further, a pathological SVV deviation by monocular testing of the non-affected eye was also more common in central (77.3%) than in peripheral OMP (38.9%). The presence of all three factors has a positive predictive value of 100% (CI 50–100%) for the presence of a central lesion.

Conclusions

In acute diplopia due to central OMP, the most important accompanying symptom is vertigo/dizziness, and the most important clinical signs are central ocular motor disorders (which require examination of the non-paretic eye) and an SVV deviation in the non-paretic eye.

A Prospective Analysis of Lesion-Symptom Relationships in Acute Vestibular and Ocular Motor Stroke

Background: Diagnosing stroke as a cause of acute vertigo, dizziness, or double vision remains a challenge, because symptom characteristics can be variable. The purpose of this study was to prospectively investigate lesion-symptom relationships in patients with acute vestibular or ocular motor stroke.

Methods: Three hundred and fifty one patients with acute and isolated vestibular or ocular motor symptoms of unclear etiology were enrolled in the EMVERT lesion trial. Symptom quality was assessed by the chief complaint (vertigo, dizziness, double vision), symptom intensity by the visual analog scale, functional impairment by EQ-5D-5L, and symptom duration by daily rating. Acute vestibular and ocular motor signs were registered by videooculography. A standardized MRI (DWI-/FLAIR-/T2-/T2^*-/3D-T1-weighted sequences) was recorded within 7 days of symptom onset. MRIs with DWI lesions were further processed for voxel-based lesion-symptom mapping (VLSM).

Results: In 47 patients, MRI depicted an acute unilateral stroke (13.4%). The chief complaints were dizziness (42.5%), vertigo (40.4%) and double vision (17.0%). Lesions in patients with vertigo or dizziness showed a large overlap in the cerebellar hemisphere. VLSM indicated that strokes in the medial cerebellar layers 7b, 8, 9 were associated with vertigo, strokes in the lateral cerebellar layer 8, crus 1, 2 with dizziness, and pontomesencephalic strokes with double vision. Symptom intensity and duration varied largely between patients. Higher symptom intensity and longer duration were associated with medial cerebellar lesions. Hemispheric lesions of the cortex were rare and presented with milder symptoms of shorter duration.

Conclusions: Prospective evaluation of patients with acute vestibular or ocular motor stroke revealed that symptom quality, intensity and duration were not suited to differentiating peripheral from central etiologies. Lesions in the lateral cerebellum, thalamus, or cortex presented with unspecific, mild and transient symptoms prone to being misdiagnosed.

Update on HINTS Plus, With Discussion of Pitfalls and Pearls

BACKGROUND AND PURPOSE

The team that manages acute vertigo in patients requires multispecialty skills. This special interest article offers a simplified list of common pitfalls to be avoided when applying the HINTS (Head-Impulse, Nystagmus, Test-of-Skew) Plus examination protocol in patients with acute vertigo. Benign paroxysmal positional vertigo is the most frequent cause of positional vertigo. The lack of systematic evaluation of symptom duration and triggers, and/or incomplete target examination, leads to improper diagnosis and management. Pitfalls to avoid and pearls to apply are offered to avoid misclassification of acute vertigo.

SUMMARY OF KEY POINTS

Appropriate, expeditious treatment implemented upon diagnostic certainty by the first health professional evaluating the patient is key to a good outcome. The absence of a typical positional nystagmus is particularly concerning for an alternative diagnosis. Misclassification of the type of vertigo leads to potential diagnostic error. The HINTS Plus examination is useful when applied to the correct clinical scenario. The most common misclassification of vertigo relates to an inability to detect spontaneous nystagmus suppressed by visual fixation and subsequent classification and treatment for positional vertigo. The second most common classification relates to inadequate evaluation of the HINTS Plus examination.

RECOMMENDATIONS FOR CLINICAL PRACTICE

Through an organized evaluation of the acutely vertiginous patient, common pitfalls in the classification of vertigo can be avoided. Such an evaluation leads to identification of those patients who require canal repositioning maneuvers and those who need referral for evaluation of other causes.

Risk of acute brain lesions in dizzy patients presenting to the emergency room: who needs imaging and who does not?

The usefulness of brain imaging studies in dizzy patients presenting to the emergency department (ED) is controversial. We aimed to assess the ‘real-world’ probability of ischemic stroke and other acute brain lesions (ABLs) in these patients to create an algorithm that helps decision-making on whether which and when brain imaging is needed. By reviewing medical records, we identified 610 patients presenting with dizziness, vertigo or imbalance to our university hospital’s ED and receiving neurological workup. We collected timing/triggers of symptoms, ABCD² score, focal neurological abnormalities, HINTS (head impulse, nystagmus, test-of-skew) and other central oculomotor signs. ABLs were extracted from CT/MRI reports. Uni-/multivariate logistic regression analyses investigated associations between clinical parameters and ABLs. Finally, the likelihood of ABLs was assessed for different clinically defined subgroups (‘dizziness syndromes’). Early CT (day 1) was performed in 539 (88%) and delayed MR imaging (median: day 4) in 299 (49%) patients. ABLs (89% ischemic stroke) were revealed in 75 (24%) of 318 patients with adequate imaging (MRI or lesion-positive CT). The risk for ABLs increased with the presence of central oculomotor signs (odds ratio 2.8, 95% confidence interval 1.5–5.2) or focal abnormalities (OR 3.3, 95% CI 1.8–6.2). The likelihood of ABLs differed between dizziness syndromes, e.g., HINTS-negative acute vestibular syndrome: 0%, acute imbalance syndrome with ABCD²-score ≥ 4: 50%. We propose a clinical pathway, according to which patients with HINTS-negative acute vestibular syndrome should not receive brain imaging, whereas imaging is suggested in dizzy patients with acute imbalance, central oculomotor signs or focal abnormalities.

Acute and episodic vestibular syndromes caused by ischemic stroke: predilection sites and risk factors

Objective

This study was performed to investigate the predilection sites of acute vestibular syndrome (AVS) and episodic vestibular syndrome (EVS) caused by acute infarcts.

Methods

This retrospective cohort study was performed at a stroke center in a tertiary teaching hospital. We diagnosed patients with AVS/EVS caused by acute ischemic stroke using diffusion-weighted imaging (DWI) and magnetic resonance angiography.

Results

Among all patients with AVS/EVS, 68 had DWI-positive ischemic events and 113 had DWI-negative ischemic events. Of the 68 patients with positive DWI findings, 42.6% had acute infarcts in the anterior circulation and 41.2% had acute infarcts in the posterior circulation. The main stroke predilection sites were the insular cortex (22.1%) and posterior thalamus (11.8%). Large vessel stenosis/occlusion (odds ratio, 0.12; 95% confidence interval, 0.04–0.36) and focal neurological symptoms/signs (odds ratio, 0.27; 95% confidence interval, 0.10–0.72) were significantly associated with the risk of AVS/EVS in patients with acute ischemic stroke.

Conclusions

The main predilection sites of AVS/EVS caused by ischemic stroke are the insular cortex and posterior thalamus. The risk of AVS/EVS is associated with large vessel stenosis and focal symptoms.

Approaching Acute Vertigo With Diplopia: A Rare Skew Deviation in Vestibular Neuritis

Evaluating the patient with acute constant vertigo or diplopia can be a daunting task for clinicians, who recognize that such symptoms can be the manifestation of potentially devastating disorders like stroke but may be uncomfortable eliciting and interpreting the key symptoms and subtle signs that distinguish dangerous from benign causes. We present a novel and highly instructive case of a patient with acute vertigo and binocular diplopia from a large skew deviation due to vestibular neuritis. As the case unfolds, text and video commentary guide the clinician through the important elements of the history, bedside examination, and laboratory evaluation necessary for accurate diagnosis in the acute vestibular syndrome. We demonstrate how to interpret nystagmus and properly perform the head impulse test and test of skew deviation and discuss the pitfalls of overreliance on imaging when evaluating patients with acute vertigo.

Relation of infarction location and volume to vertigo in vertebrobasilar stroke

OBJECTIVE

Vertigo is a common presentation of vertebrobasilar stroke. Anecdotal reports have shown that vertigo occurs more often in multiple than in single brainstem or cerebellar infarctions. We examined the relation between the location and volume of infarction and vertigo in patients with vertebrobasilar stroke.

METHODS

Consecutive patients with vertebrobasilar stroke were prospectively recruited. The infarction location and volume were assessed in the diffusion-weighted magnetic resonance imaging.

RESULTS

Fifty-nine patients were included, 32 (54.2%) with vertigo and 27 (45.8%) without vertigo. The infarction volume did not correlate with National Institute of Health Stroke Scale (NIHSS) score on admission (Spearman ρ = .077, p = .56) but correlated with modified Rankin Scale (ρ = .37, p = .004) on discharge. In the vertigo group, the proportion of men was lower (53.1% vs. 77.8%, p = .049), fewer patients had focal neurological deficits (65.6% vs. 96.3%, p = .004), patients tended to present later (median [IQR] was 7.5 [4-46] vs. 4 [2-12] hours, p = .052), numerically fewer patients received intravenous thrombolysis (15.6% vs. 37%, p = .06), and the total infarction volume was larger (5.6 vs. 0.42 cm³ , p = .008) than in nonvertigo group. In multivariate logistic regression, infarction location either in the cerebellum or in the dorsal brainstem (odds ratio [OR] 16.97, 95% CI 3.1-92.95, p = .001) and a total infarction volume of >0.48 cm³ (OR 4.4, 95% CI 1.05-18.58, p = .043) were related to vertigo. In another multivariate logistic regression, after adjusting for age, sex, intravenous thrombolysis, serum level of white blood cells, and atrial fibrillation, vertigo independently predicted a total infarction volume of >0.48 cm³ (OR 5.75, 95% CI 1.43-23.08, p = .01).

CONCLUSION

Infarction location in the cerebellum and/or dorsal brainstem is an independent predictor of vertigo. Furthermore, larger infarction volume in these structures is associated with vertigo. A considerable proportion of patients with vascular vertigo present without focal neurological deficits posing a diagnostic challenge. National Institute of Health Stroke Scale is not sensitive for vertebrobasilar stroke.

Differential diagnosis of acute vascular vertigo

PURPOSE OF REVIEW

The current review covers recent advances in vascular vertigo in terms of diagnostic strategies, clinical/laboratory features, pathophysiology, and differential diagnosis.

RECENT FINDINGS

Acute strokes presenting with isolated dizziness/vertigo without other obvious symptoms or signs of central nervous system involvements may be easily mistaken as peripheral vestibulopathy. For correct diagnosis of vascular vertigo, the importance of clinical history (timing and triggers) and targeted bedside examination cannot be overemphasized. In addition to Head Impulse-Nystagmus-Test of Skew, several differential strategies have been advanced by adopting a combination of clinical history, bedside or laboratory examination, and imaging for diagnosis of vascular vertigo. Circumscribed cerebellar and brainstem lesions may cause isolated central vestibular syndromes with characteristic vestibular and ocular motor manifestations. Recognition of these findings would aid in localizing the lesions and understanding the function of each central vestibular structure. Central positional nystagmus (CPN) may mimic benign paroxysmal positional vertigo (BPPV), but additional oculomotor or neurological findings mostly permit differentiation of CPN from BPPV.

SUMMARY

In acute vestibular syndrome, discriminating vascular causes is still challenging especially when other central symptoms and signs are not evident. An integrated approach based on understanding of clinical features, laboratory findings, speculated mechanisms, and limitations of current diagnostic tests will lead to better clinical practice.

Ocular Motor and Vestibular Disorders in Brainstem Disease

The brainstem contains ocular motor and vestibular structures that, when damaged, produce specific eye movement disorders. In this review, we will discuss three brainstem syndromes with characteristic ocular motor and vestibular findings that can be highly localizing. First, we will discuss the lateral medullary (Wallenberg) syndrome, focusing on ocular lateropulsion, saccadic dysmetria, and the ocular tilt reaction. Second, we will review the medial longitudinal fasciculus syndrome including the ocular tilt reaction, nystagmus, and the vestibular-ocular reflex. Lastly, we will discuss hypertrophic olivary degeneration and oculopalatal tremor, which may develop weeks to months after a brainstem or cerebellar lesion. In these syndromes, the clinical ocular motor and vestibular examination is instrumental in localizing the lesion.

Avoiding Misdiagnosis in Patients With Posterior Circulation Ischemia: A Narrative Review

Posterior circulation strokes represent 20% of all acute ischemic strokes. Posterior circulation stroke patients are misdiagnosed twice as often compared to those with anterior events. Misdiagnosed patients likely have worse outcomes than correctly diagnosed patients because they are at risk for complications of the initial stroke as well as recurrent events due to lack of secondary stroke prevention and failure to treat the underlying vascular pathology. Understanding important anatomic variants, the clinical presentations, relevant physical examination findings, and the limitations of acute brain imaging may help reduce misdiagnosis. We present a symptom-based review of posterior circulation ischemia focusing on the subtler presentations with a brief discussion of basilar stroke, both of which can be missed by the emergency physician. Strategies to avoid misdiagnosis include establishing an abrupt onset of symptoms, awareness of the nonspecific presentations, consideration of basilar stroke in altered patients and using a modern approach to diagnosis of the acutely dizzy patient.

High-sensitivity C-reactive protein as an indicator of ischemic stroke in patients with isolated acute vestibular syndrome: Retrospective observational study

Ischemic strokes presenting with isolated acute vestibular syndrome (AVS) are not rare and still are challenging for diagnosis. In this retrospective study, we aimed to investigate the association of high-sensitivity C-reactive protein (hs-CRP) with stroke in patients with isolated AVS. A total of 217 patients with isolated AVS within 3 days of symptom onset were included. Serum hs-CRP levels were assessed within 24 hours of admission. The relationship between hs-CRP levels and stroke in patients with AVS were analyzed using univariate and multivariate models. The results showed that hs-CRP levels were significantly higher in infarction patients than that in noninfarction group. The stroke occurrence was increased with increasing quartile levels of hs-CRP. The highest quartile level of hs-CRP was associated with a higher occurrence of stroke compared with the lowest quartile group (adjusted odds ratio [OR], 4.099; 95% confidence interval [CI], 1.272-13.216; P = .018). We also found that male gender (adjusted OR, 5.635; 95% CI, 2.212-14.352; P < .001) and increased low-density lipoprotein cholesterol (LDL-C) (adjusted OR, 2.543; 95% CI, 1.175-5.505; P = .018) were independently associated with stroke in patients with AVS. In addition, using the receiver operating characteristic curve analysis, our study yielded a threshold value of hs-CRP at 1.82 mg/L, and demonstrated that combining hs-CRP with LDL-C improved the discriminatory ability to identify stroke patients with AVS (area under the curve of the combined model: 0.753; 95% CI = 0.684-0.821; P < .001). Hs-CRP may be a useful indicator of stroke in patients with AVS. More attention should be paid to the patients with elevated hs-CRP level.

Acute dizziness with potential life-threatening event: A case series from single ICU

BACKGROUND

Whether the acute dizziness would be associated with potentially life-threatening event, which was previously unknown.

METHODS

Between Jan 2014 and Dec 2016, We performed a retrospective survey to investigate the clinical data of patients with acute dizziness from an intensive care unit (ICU) in China. Inclusion criteria for all cases were presented with acute dizziness at onset, and then with a potentially life-threatening event. Baseline data and 30-days outcomes were collected.

RESULTS

Approximately 1.0% of ICU patients had an acute dizziness with potentially life-threatening events. The median age of patients was 60 years (range 23 to 81 years), male: female ratio was 1.8:1. The causes of acute dizziness included focal cerebral hemorrhage in 15 cases (60%), shock in 7cases (28%), and cerebral infarction in 3 cases (12%). The most frequent potentially life-threatening event was acute brain failure (24/25), and the most common cause leading to brain failure was the lesion enlarged (54.2%, including hematoma enlargement in 8 cases, large area infarction or new infarction in 3 cases, and intraventricular hemorrhage in 2 cases). The second potentially life-threatening event was septic shock/secondary sepsis (45.8%). The fatality rate for all life- threatening events was in 64%. Compared with the survival group, the patients with lesion enlarged (56.3% vs. 11.1%, p < 0.05), acute respiratory failure (93.8% vs. 55.6% p < 0.05), lactate level (5.3 mmol/l vs. 1.3 mmol/l, p < 0.05), and Sequential Organ Failure Assessment (SOFA) score (6.9 vs. 3.4, p < 0.0001) in the non-survival group were significantly higher, while late mean arterial blood pressure (84.6 mmHg vs.124 mmHg, p < 0.0001), GCS score (5.0 score vs. 15 score, p < 0.0001) in the non-survival group were significantly lower.

CONCLUSION

Acute dizziness with potentially life-threatening events accounts for about 1% of adult ICU patients. Acute dizziness in ICU patients is associated with a high risk of death within 30 days of onset.

Migraine as a Stroke Mimic and as a Stroke Chameleon

PURPOSE OF REVIEW

This review details the frequency of and ways in which migraine can be both an ischemic stroke/transient ischemic attack mimic (false positive) and chameleon (false negative). We additionally seek to clarify the complex relationships between migraine and cerebrovascular diseases with regard to diagnostic error.

RECENT FINDINGS

Nearly 2% of all patients evaluated emergently for possible stroke have an ultimate diagnosis of migraine; approximately 18% of all stroke mimic patients treated with intravenous thrombolysis have a final diagnosis of migraine. Though the treatment of a patient with migraine with thrombolytics confers a low risk of complication, symptomatic intracerebral hemorrhage may occur. Three clinical prediction scores with high sensitivity and specificity exist that can aid in the diagnosis of acute cerebral ischemia. Differentiating between migraine aura and transient ischemic attacks remains challenging. On the other hand, migraine is a common incorrect diagnosis initially given to patients with stroke. Among patients discharged from an emergency visit to home with a diagnosis of a non-specific headache disorder, 0.5% were misdiagnosed. Further development of tools to quantify and understand sources of stroke misdiagnosis among patients who present with headache is warranted. Both failure to identify cerebral ischemia among patients with headache and overdiagnosis of ischemia can lead to patient harms. While some tools exist to help with acute diagnostic decision-making, additional strategies to improve diagnostic safety among patients with migraine and/or cerebral ischemia are needed.

Posterior circulation stroke diagnosis using HINTS in patients presenting with acute vestibular syndrome: A systematic review

Purpose

Acute vestibular syndrome - vertigo, nausea/vomiting, nystagmus and gait unsteadiness - is common, and differentiating posterior circulation stroke from a peripheral cause can be challenging. The National Institute of Health Stroke Scale (NIHSS) does not include acute vestibular syndrome, and early computed tomography scanning cannot rule out acute ischaemia. A positive Head Impulse-Nystagmus-Test of Skew (HINTS) test suggests posterior circulation stroke in acute vestibular syndrome when any of three signs are present: normal horizontal head impulse, gaze-direction nystagmus or eye skew deviation. This systematic review examined the accuracy of positive HINTS in identifying posterior circulation stroke in acute vestibular syndrome patients.

Methods

We searched MEDLINE (1966 to 21 December 2017), EMBASE (1980 to December 2017), Web of Science and scanned bibliographies. Two authors independently screened relevant articles and extracted data. We included studies where HINTS was used to identify posterior circulation stroke with diagnosis confirmed using magnetic resonance imaging.

Findings

Six studies (n = 644 patients) were identified. Acute stroke was confirmed in 200 (31.1%) patients. There was a 15-fold increased risk of posterior circulation stroke in patients with positive HINTS test compared to those with no abnormality (RR: 15.84, 95% CI: 5.25-47.79). For any stroke, the pooled sensitivity was 95.5% (95% CI: 92.6-98.4%) and specificity was 71.2% (95% CI: 67.0-75.4%).

Discussion and Conclusion

The data suggest that the HINTS test as one element of clinical evaluation is useful to differentiate posterior circulation stroke from peripheral causes in acute vestibular syndrome. Further studies are needed to validate HINTS as a clinical prediction tool in emergency department settings and selection of patients for reperfusion treatment.

Optokinetic Analysis in Patients With Spontaneous Horizontal Gaze-Evoked Nystagmus Without Radiological Neuropathology

Gaze-evoked nystagmus is not rare among those who have acute balance problem and may indicate a cerebellar dysfunction that is associated with a broad spectrum of disorders. The aim of this study is to analyze optokinetic response in those patients. Eleven males and 7 females (age range: 25-60, 42.5 [9.75]) with gaze-evoked nystagmus were analyzed with optokinetic test (Micromed Inc). Nystagmus was elicited by a stimulator light spot moving across the patient's visual field at a target speed of 30 degree/second. Ten age-matched healthy participants served as controls. The gain and slow-phase velocity difference in oculomotor response from left and right stimulus was compared in patients and the control participants. One-way analysis of variance test was used for multiple variance analysis of the groups. Statistical significance was set at P < .05. Slow-phase velocity of gaze-evoked nystagmus was ranging between 6 and 19 degree/second. The mean slow-phase velocity of gaze-evoked nystagmus to the right and left was 8.1 (3.81) and 6.8 (4.67) degree/second, respectively. Optokinetic gain was out of normal limits in 10 (55.5%) patients. Comparison of mean gain difference between the patients and the normal participants was statistically significant (P = .025). No statistical difference was found in mean slow-phase velocity difference in optokinetic nystagmus between control participants and patients (P > .05 [.099]). An acute-onset balance problem may be associated with dysfunction of separate populations of neurons in the brainstem and cerebellum even if there is no radiological neuropathy since gaze-evoked nystagmus is a sign of neural integrator dysfunction. Patients with gaze-evoked nystagmus and optokinetic abnormalities may have disruption of cerebellar pathways and should be followed closely.

Comparison of acute vertigo diagnosis and treatment practices between otolaryngologists and non-otolaryngologists: A multicenter scenario-based survey

Acute vertigo is a common problem in emergency departments. However, clinical strategies of acute vertigo care vary among care providers. The aim of the study was to investigate differences in diagnosis [Dix-Hallpike test, the head impulse, nystagmus, and the test of skew (HINTS) procedure, and imaging modalities] and treatment (pharmacological treatments and the Epley maneuver) by otolaryngologists and non-otolaryngologists in emergency medicine settings. We used a multicenter case-based survey for the study. Four clinical vignettes of acute vertigo (posterior canal benign paroxysmal positional vertigo, vestibular neuritis, Meniere disease, and nonspecific vertigo) were used. Total 151 physicians from all study sites participated in the study. There were 84 non-otolaryngologists (48 emergency physicians and 36 internists) and 67 otolaryngologists. The multivariate analysis indicated that otolaryngologists ordered fewer CT scans (odds ratio (OR), 0.20; 95% confidence interval (CI), 0.07-0.53) and performed fewer HINTS procedures (OR, 0.17; 95% CI, 0.06-0.46), but used the Dix-Hallpike method more often (OR, 2.36; 95% CI, 1.01-5.52) for diagnosis compared to non-otolaryngologists. For treatment, otolaryngologists were less likely to use the Epley method (OR, 0.19; 95% CI, 0.07-0.53) and metoclopramide (OR, 0.09; 95% CI, 0.01-0.97) and more likely to use sodium bicarbonate (OR, 20.50; 95% CI, 6.85-61.40) compared to non-otolaryngologists. We found significant differences in the acute vertigo care provided by non-otolaryngologists and otolaryngologists from a vignette-based research. To improve acute vertigo care, educational systems focusing on acute vertigo are needed.

Diagnostic value of eye movement and vestibular function tests in patients with posterior circulation infarction

OBJECTIVE

To evaluate the diagnostic value of eye movements and vestibular function tests in PCI patients.

METHODS

Thirty-eight PCI patients and 31 patients with unilateral vestibular neuritis (UVN) were enrolled and underwent eye movement tests and vestibular function tests (spontaneous nystagmus [SN], head-shaking nystagmus [HSN]).

RESULTS

The rates of eye movement abnormality were 78.9% and 41.9% in PCI and UVN patients, respectively. The positive rate of SN and HSN were, respectively, 41.2% and 43.8% in cerebellar infarction patients, 33.3% and 66.7% in medullary infarction patients, and 100.0% and 86.2% in UVN patients. The horizontal direction of SN and HSN coincided with the affected side in cerebellar infarction patients, and the healthy side in UVN patients, which coincided with the healthy side and the affected side, respectively in medullary infarction patients. The horizontal direction of HSN was bidirectional nystagmus in 16.0% (4/25) of UVN patients.

CONCLUSIONS AND SIGNIFICANCE

Eye movement and vestibular function tests contribute to the early diagnosis of PCI. The horizontal direction of SN and HSN are consistently toward the affected side in cerebellar infarction patients and the healthy side in UVN patients, in contrast to medullary infarction patients, and deserve further investigations.

Dizziness

Dizziness is a common symptom encountered by all physicians. Dizziness and related symptoms are frequently linked to 1 or more of a list of contributors that includes benign paroxysmal positional vertigo, Ménière disease, migraine, acute peripheral vestibulopathy, cerebral ischemia, and anxiety disorders. Awareness of these common clinical patterns increases the likelihood of making a rapid, accurate diagnosis.

Use of HINTS in the acute vestibular syndrome. An Overview

Following the initial description of HINTS to diagnose acute vestibular syndrome (AVS) in 2009, there has been significant interest in the systematic evaluation of HINTs to diagnose stroke and other less common central causes of AVS. This trend increased with availability of the video head impulse test (video-HIT). This article reviews the original papers and discusses the main publications from 2009 to 2017. Many authors use video-HIT in the diagnosis of patients with AVS; this paper focuses on the major publications on the topic featuring nystagmus, manual and video-HIT, and skew deviation. Twenty-five papers provide a summary of the last 8 years' application of HINTS, the video-HIT added quantitative information to the early clinical observations. Further research will undoubtedly provide specific combination of abnormalities with high degree of lesion localisation and aetiology. In a short time following the original description, neurotologist and neurologists in the evaluation of AVS use the HINTS triad. The introduction of the video-HIT added greater understanding of the complex interaction between the primary vestibular afferents, brainstem and cerebellum. In addition, it permits evaluation of the angular vestibulo-ocular reflex in the plane of all six semicircular canals, with accurate peripheral versus central lesion localisation often corroborated by brain imaging.

Benign paroxysmal positional vertigo in the elderly: current insights

Balance disorders, unsteadiness, dizziness and vertigo in the elderly are a significant health problem, needing appropriate treatment. One third of elderly patients with vertigo were diagnosed with benign paroxysmal positional vertigo (BPPV), the most common cause of dizziness in both primary care specialist Neurology and Ear Nose Throat settings. BPPV presents a specific paroxysmal positional nystagmus which can be obtained using the appropriate diagnostic positional test and can be treated effectively using specific therapeutic maneuvers. This review presents current insights into the diagnostic, pathogenetic and therapeutic aspects of BPPV in the elderly. BPPV in older patients does not differ significantly from BPPV in younger patients, with regard to pathogenesis, diagnosis and treatment. However, in older patients, its prevalence is higher and it responds less effectively to treatment, having a tendency for recurrence. Specific issues which should be considered in the elderly are: 1) difficulty in obtaining an accurate history; 2) difficulty in performing the diagnostic and therapeutic maneuvers, which should be executed with slow and gentle movements and extremely cautiously to avoid any vascular or orthopedic complications; and 3) the relation between BPPV and falls.

Early MRI-negative posterior circulation stroke presenting as acute dizziness

The aim of this study was to determine the frequency, clinical and radiological features, and efficacy of clinical evaluation and perfusion-weighted imaging (PWI) for the prediction of final stroke in patients with DWI/MRI-negative posterior circulation stroke (PCS) presenting acute dizziness/vertigo. From our comprehensive prospective stroke registry of acute ischemic stroke during a 7-year period, we identified 1846 consecutive patients with PCS, 850 of whom presented with acute dizziness/vertigo. Of these 850 patients, initial DWI-MRI was negative in 35 (4.1%). In these 35 patients, dizziness/vertigo was acute prolonged in 31 and recurrent transient in 4. Focal neurological signs or profound imbalance were present in 16/35 or 18/34, respectively. Spontaneous nystagmus was absent in 21/35; the HINTS protocol (head impulse, nystagmus, and test-of-skew) was not applicable to them. In 12/26 patients, PWI was positive and the same time as DWI was negative. The usual site of lesion was the lateral medulla (n = 18). Twenty-nine patients (83%) had small strokes, while 19 (54%) had large vessel strokes. The sensitivity of systematic clinical evaluation adopting neurological examination, HINTS plus, and assessment of equilibrium was 83%, for prediction of final stroke and 100% when combined with PWI. An integrated approach using systematic neurological and neuro-otological examinations combined with PWI accurately diagnoses PCS presenting with acute dizziness/vertigo. Although most patients with acute vertigo and MRI-negative PCS have small brainstem strokes, about a half have large vessel stroke with greater risk of progression requiring prompt treatment.

Lesion Topography and Its Correlation With Etiology in Medullary Infarction: Analysis From a Multi-Center Stroke Study in China

Objectives: The lesion topography of medullary infarction (MI) is heterogeneous and its correlation with stroke etiology remains elusive. We aim to clarify the lesion pattern of MI and to assess its correlation with stroke etiology.

Material and Methods: Of 1129 subjects with available DWI in SMART study (a multi-center trial concerning secondary stroke prevention in China) between April 2008 and December 2010, 43 patients with DWI confirmed MI (3.8%) were retrospectively evaluated. Lesions were categorized as lateral and medial medullary infarction (LMI and MMI, 33 and 10 subjects respectively) at 3 levels rostro-caudally and correlated with the stroke etiology. Clinical profiles and long-term prognosis were analyzed.

Results: Large artery atherosclerosis, small vessel occlusion, cardiogenic embolism and artery dissection accounted for 29, 11, 1, and 2 infarcts, respectively. Large artery disease was the most common cause in LMI (24 of 33, 72.7%) whereas small vessel occlusion was not uncommon in MMI (5 of 10, 50.0%). Though the difference of infarct pattern between large artery atherosclerosis and small vessel occlusion was insignificant, two distinct lesion patterns were considered to be relevant: (1) Rostral MMI with continuous medial pontine infarctions were more likely attributed to small vessel occlusion than large artery atherosclerosis. Kameda et al. (2) MMI with ventral to dorsal extension were more often caused by large artery disease than small vessel occlusion. Median NIHSS at admission was 4. During a median follow-up of 17 months, 2 patients died and 2 experienced recurrent ischemic events, 39 of 41 subjects (95.1%) were functional independent (mRS 0–2).

Conclusions: This multi-center study demonstrates that MI has distinct lesion pattern depending on various stroke etiologies and mechanisms. Future investigations with larger sample size should establish the lesion pattern of MI and validate its correlation with the stroke etiology and mechanisms, which might improve stroke management.

Central vertigo

PURPOSE OF REVIEW

This review considers recent advances in central vertigo in terms of clinical and laboratory features and pathophysiology.

RECENT FINDINGS

Strokes presenting dizziness-vertigo are more likely to be associated with a misdiagnosis in the emergency setting. The risk of future strokes after discharge is higher in patients diagnosed with peripheral vertigo than in control patients. Strokes and transient ischemic attacks account for one-quarter of acute transient vestibular syndrome. Diagnosis of acute combined central and peripheral vestibulopathy such as anterior inferior cerebellar artery infarction requires additional consideration whenever applying the HINTS (head impulse test, direction-changing gaze-evoked nystagmus, and test of skew). Heat illness and metronidazole have been recognized as new causes of central vestibulopathy. Some new findings have also been added to the clinical and laboratory features of central vertigo.

SUMMARY

Central vertigo is a heterogeneous group of disorders with diverse clinical spectrums. An integrated approach based on understanding of clinical features, laboratory findings, speculated mechanisms, and limitations of current diagnostic tests will lead to better clinical practice.

Clinical and video head impulse test in the diagnosis of posterior circulation stroke presenting as acute vestibular syndrome in the emergency department

INTRODUCTION

Head impulse test (HIT) is the critical bedside examination which differentiates vestibular neuritis (VN) from posterior circulation stroke (PCS) in acute vestibular syndrome (AVS). Video-oculography based HIT (vHIT) may have aadditional strength in making the differentiation.

METHODS

Patients admitted to the emergency department of a tertiary-care medical center with AVS were studied. An emergency specialist and a neurologist performed HIT. vHIT was conducted by an neuro-otology research fellow.

RESULTS

Forty patients 26 male, 14 female with a mean age of 49 years were included in the analyses. Final diagnoses were VN in 24 and PCS in 16 patients.In the VN group, clinical HIT was assessed as abnormal in 19(80%) cases by the emergency specialist and in 20(83%) by the neurologist. In all PCS patients, HIT was recorded as normal both by the emergency specialist and the neurologist (100%).On vHIT, patients with VN had significantly low gain values for both the ipsilesional and contralesional sides when compared with the healthy controls, with significantly lower figures for the ipsilesional side (p < 0.001). All patients in this group had normal DWI-MRI.PCS patients had bilaterally low gain (p < 0.05) on vHIT. However, gain asymmetry was not significant. Subgroup analyses according to presence of brainstem involvement revealed bilateral low gain (p < 0.05) in patients with brainstem infarction (anterior inferior cerebellar artery-posterior inferior cerebellar artery stroke, AICA-PICA stroke) whereas patients with pure cerebellar infarction (posterior inferior cerebellar artery-superior cerebellar artery stroke, PICA-SCA stroke) had gain values similar to healthy controls.With a gain cut-off ≤0.75 and gain asymmetry cut-off ≥17%, as determined by ROC analysis, 100% of PCS patients and 80% of VN patients were correctly diagnosed.

CONCLUSIONS

Clinical HIT, either performed by an emergency specialist or neurologist is equivalent to vHIT gain and gain asymmetry analysis as conducted by neuro-otologist in the diagnosis of PCS, albeit mislabeling about 20% of VN patients. vHIT does not appear to yield additional diagnostic information. These findings indicate the strength of clinical HIT. Pure gain-based vHIT analysis seems limited and needs to be incorporated with saccade analysis.