Vascular vertigo and dizziness: managing and treating outpatients

OBJECTIVE

Due the lack of data on the treatment of Vascular Vertigo and Dizziness, this study aimed to report how we managed and treated those outpatients according to the recently introduced American Heart Association and Stroke Association guidelines.

METHODS

We conducted a longitudinal case series from May 2022 to February 2023. We included patients who met the Bárány Society's Vascular Vertigo and Dizziness classification and were eligible for therapy in accordance with the American Heart Association and Stroke Association guidelines, featuring aspects of the stroke group and transient attack group.

RESULTS

Overall, 41 patients (51.2% female; median age 72 years) were enrolled; 10 (24.3%) had ischemic strokes, 30 (73.1%) had transient ischemic attack, and 1 (2.4%) had a probable isolated labyrinthine infarction. The patients received dual antiplatelet (48.7%), single antiplatelet therapy (48.7%), and anticoagulant therapy (2.4%). No new crises occurred in 95.2% of the patients, and the transient ischemic attack group showed a significant decrease in discomfort from imbalance on the visual analog scale.

CONCLUSIONS

Antiplatelets and anticoagulants are safe and effective in treating Vascular Vertigo and Dizziness as they prevent new ischemic events and increase the flow of the posterior circulation, reducing vertigo/dizziness attacks and imbalance complaints.

LEVEL OF EVIDENCE: 4

Consensus paper on the management of acute isolated vertigo in the emergency department

Acute vertigo is defined as the perception of movement of oneself or the surroundings in the absence of actual motion and it is a frequent cause for emergency department admissions. The utilization of medical resources and the duration of hospital stay for this kind of symptom is high. Furthermore, the efficiency of brain imaging in the acute phase is low, considering the limited sensitivity of both CT and MRI for diagnosing diseases that are the causes of central type of vertigo. Relying on imaging tests can provide false reassurance in the event of negative results or prolong the in-hospital work-up improperly. On the other hand, clinical examinations, notably the assessment of nystagmus' features, have proven to be highly accurate and efficient when performed by experts. Literature data point out that emergency physicians often do not employ these skills or use them incorrectly. Several clinical algorithms have been introduced in recent years with the aim of enhancing the diagnostic accuracy of emergency physicians when evaluating this specific pathology. Both the 'HINTS and 'STANDING' algorithms have undergone external validation in emergency physician hands, showing good diagnostic accuracy. The objective of this consensus document is to provide scientific evidence supporting the clinical decisions made by physicians assessing adult patients with acute vertigo in the emergency department, particularly in cases without clear associated neurological signs. The document aims to offer a straightforward and multidisciplinary approach. At the same time, it tries to delineate benchmarks for the formulation of local diagnostic and therapeutic pathways, as well as provide a base for the development of training and research initiatives.

Development of a Clinical Risk Score to Risk Stratify for a Serious Cause of Vertigo in Patients Presenting to the Emergency Department

STUDY OBJECTIVE

Identify high-risk clinical characteristics for a serious cause of vertigo in patients presenting to the emergency department (ED).

METHODS

Multicentre prospective cohort study over 3 years at three university-affiliated tertiary care EDs. Participants were patients presenting with vertigo, dizziness or imbalance. Main outcome measurement was an adjudicated serious diagnosis defined as stroke, transient ischemic attack, vertebral artery dissection or brain tumour.

RESULTS

A total of 2,078 of 2,618 potentially eligible patients (79.4%) were enrolled (mean age 77.1 years; 59% women). Serious events occurred in 111 (5.3%) patients. We used logistic regression to create a 7-item prediction model: male, age over 65, hypertension, diabetes, motor/sensory deficits, cerebellar signs/symptoms and benign paroxysmal positional vertigo diagnosis (C-statistic 0.96, 95% confidence interval [CI] 0.92 to 0.98). The risk of a serious diagnosis ranged from 0% for a score of <5, 2.1% for a score of 5 to 8, and 41% for a score >8. Sensitivity for a serious diagnosis was 100% (95% CI, 97.1% to 100%) and specificity 72.1% (95% CI, 70.1% to 74%) for a score <5.

CONCLUSION

The Sudbury Vertigo Risk Score identifies the risk of a serious diagnosis as a cause of a patient's vertigo and if validated could assist physicians in guiding further investigation, consultation, and treatment decisions, improving resource utilization and reducing missed diagnoses.

Dizziness in Primary Care

Dizziness is a prevalent symptom in the general population and is among the most common reasons patients present for medical evaluations. This article focuses on high yield information to support primary clinicians in the efficient and effective evaluation and management of dizziness. Key points are as follows: do not anchor on the type of dizziness symptom, do use symptom timing and prior medical history to inform diagnostics probabilities, do evaluate for hallmark examination findings of vestibular disorders, and seek out opportunities to deliver evidence-based interventions particularly the canalith repositioning maneuver and gaze stabilization exercises.

Characteristics and risk of stroke in emergency department patients with acute dizziness

Background

Acute dizziness is a common symptom in the emergency department (ED), with strokes accounting for 3 %-5 % of cases. We investigated the risk of stroke in ED patients with acute dizziness and compared stroke characteristics diagnosed during and after the ED visit.

Methods

We identified adult patients with acute dizziness, vertigo, or imbalance using a hospital research-based database. Patients with abdominal or flank pain were used as the comparison group. Patients with dizziness were 1:1 matched to comparison patients. Each patient was traced for up to one year until being hospitalized for a stroke.

Results

Out of the 24,266 eligible patients, 589 (2.4 %) were hospitalized for stroke during the ED visit. For the remaining 23,677 patients, the risk of stroke at 7, 30, 90, and 365 days after ED discharge was 0.40 %, 0.52 %, 0.71 %, and 1.25 % respectively. Patients with dizziness had a higher risk of stroke compared to the comparison group at 7, 30, 90, and 365 days. The risk ratios decreased from 5.69 (95 % confidence interval [CI], 3.34-9.68) to 2.03 (95 % CI, 1.65-2.49). Compared to patients hospitalized for stroke during the ED visit, those hospitalized for stroke after the ED visit had greater stroke severity despite a lower initial triage acuity. Patients with early stroke (≤7 days) after ED discharge were less likely to have hypertension, diabetes, hyperlipidemia, and atrial fibrillation. They mostly experienced posterior circulation stroke. Patients with late stroke (>7 days) were older and less likely to have hypertension and hyperlipidemia but more likely to have a history of prior stroke and ischemic heart disease. Their strokes were mainly located in the anterior circulation territory.

Conclusions

The risk of stroke after ED discharge was higher in patients with dizziness than in the comparison group, with gradually decreasing risk ratios in the following year. Patients hospitalized for stroke during and after the ED visit had different profiles of vascular risk factors and clinical characteristics.

Recognizing Posterior Circulation Transient Ischemic Attacks Presenting as Episodic Isolated Dizziness

Diagnosing patients presenting to the emergency department with self-limited episodes of isolated dizziness (the episodic vestibular syndrome) requires a broad differential diagnosis that includes posterior circulation transient ischemic attack. Because these patients are, by definition, asymptomatic without new neurologic findings on examination, the diagnosis, largely based on history and epidemiologic context, can be challenging. We review literature that addresses the frequency of posterior circulation transient ischemic attack in this group of patients compared with other potential causes of episodic vestibular syndrome. We present ways of distinguishing posterior circulation transient ischemic attack from vestibular migraine, the most common cause of episodic vestibular syndrome. We also present a diagnostic algorithm that may help clinicians to work their way through the differential diagnosis.

Trends in the incidence of peripheral vestibular disorders: a Nationwide population-based study

Purpose

This study aimed to examines the long-term trend of incidence of peripheral vestibular disorders between 2010 and 2018 in Taiwan.

Methods

Study-eligible patients were identified from Taiwan's Longitudinal Health Insurance Database 2005 maintained by the Ministry of Health and Welfare in Taiwan. We retrieved 230,566 patients with a first-time diagnosis of peripheral vestibular disorders between 2010 and 2018. We calculated annual incidence rates of peripheral vestibular disorders per 100,000 population. We used the annual percent change (APC) to test the trend of peripheral vestibular disorders over time.

Results

The mean annual incidence rate of peripheral vestibular disorders during the study period was 1489.6 per 100,000 population. Incidence showed a statistically significant steady decrease from 2010 to 2018 with a mean APC of -6.15% (95% CI = -6.97% ~ -5.32%). The decline was led by Meniere's disease (APC = -9.83, 95% CI = -10.66% ~ -8.99%), followed by benign paroxysmal positional vertigo (APC = -3.69, 95% CI = -4.53% ~ -3.03%), vestibular neuritis (APC = -7.85, 95% CI = -8.96 ~ -6.73), and other peripheral vestibular dizziness (APC = -5.56, 95% CI = -6.69% ~ -4.43%).

Conclusion

The incidence of peripheral vestibular disorders, overall, and the four major subgroups, benign paroxysmal positional vertigo, Meniere's disease, vestibular neuritis, and other peripheral vestibular dizziness, all decreased substantially, year by year within the 2010-2018 period.

Misdiagnosis-related harm quantification through mixture models and harm measures

Investigating and monitoring misdiagnosis-related harm is crucial for improving health care. However, this effort has traditionally focused on the chart review process, which is labor intensive, potentially unstable, and does not scale well. To monitor medical institutes' diagnostic performance and identify areas for improvement in a timely fashion, researchers proposed to leverage the relationship between symptoms and diseases based on electronic health records or claim data. Specifically, the elevated disease risk following a false-negative diagnosis can be used to signal potential harm. However, off-the-shelf statistical methods do not fully accommodate the data structure of a well-hypothesized risk pattern and thus fail to address the unique challenges adequately. To fill these gaps, we proposed a mixture regression model and its associated goodness-of-fit testing. We further proposed harm measures and profiling analysis procedures to quantify, evaluate, and compare misdiagnosis-related harm across institutes with potentially different patient population compositions. We studied the performance of the proposed methods through simulation studies. We then illustrated the methods through data analyses on stroke occurrence data from the Taiwan Longitudinal Health Insurance Database. From the analyses, we quantitatively evaluated risk factors for being harmed due to misdiagnosis, which unveiled some insights for health care quality research. We also compared general and special care hospitals in Taiwan and observed better diagnostic performance in special care hospitals using various new evaluation measures.

Optimizing measurement of misdiagnosis-related harms using symptom-disease pair analysis of diagnostic error (SPADE): comparison groups to maximize SPADE validity

Diagnostic errors in medicine represent a significant public health problem but continue to be challenging to measure accurately, reliably, and efficiently. The recently developed Symptom-Disease Pair Analysis of Diagnostic Error (SPADE) approach measures misdiagnosis related harms using electronic health records or administrative claims data. The approach is clinically valid, methodologically sound, statistically robust, and operationally viable without the requirement for manual chart review. This paper clarifies aspects of the SPADE analysis to assure that researchers apply this method to yield valid results with a particular emphasis on defining appropriate comparator groups and analytical strategies for balancing differences between these groups. We discuss four distinct types of comparators (intra-group and inter-group for both look-back and look-forward analyses), detailing the rationale for choosing one over the other and inferences that can be drawn from these comparative analyses. Our aim is that these additional analytical practices will improve the validity of SPADE and related approaches to quantify diagnostic error in medicine.

Diagnostic Contribution of Magnetic Resonance Imaging and Computerized Tomography in Patients with Unidentified Vertigo and Normal Neurologic Examination in Emergency Medicine

Background

Vertigo and dizziness are common symptoms in patients presenting to emergency medicine (ED) clinics. Vertigo may be caused by peripheral or central origin. Routine imaging is not indicated; however, neuroimaging is increasing, and published studies have revealed a small number of positive findings on imaging modalities.

Aims

The aim of this study was to investigate whether neurological imaging was necessary in patients classified as "unidentified vertigo," who were admitted to the emergency department with vertiginous complaints and not revealing typical peripheral vertigo findings and any neurological deficits.

Materials and Methods

All patients with "dizzy symptoms" were included in the study. For patients who met the definition of "unidentified vertigo," experimental neurological imaging studies were done. Head computerized tomography (CT), magnetic resonance imaging (MRI) with gradient-echo sequences (GRE), and diffusion weighted images (DWI) were used for imaging. Patients who underwent neuroimaging in the ED were followed up for 6 months in Neurology and ENT clinics.

Results

A total of 351 patients were included in the study. Experimental imaging was performed on 100 patients. CT detected a significant pathology associated with the vertigo complaint in only one patient. MRI results were similar to the CT results. MRI-GRE sequences showed some additional pathologies in 14 patients and 4 of them were thought to be related to vertiginous symptoms. None of the patients classified as "non-central causes of vertigo" in the neuroimaging group developed TIA or CVD during 6 months of follow-up.

Conclusion

Head CT can be adequate to exclude life-threatening central pathology in "undifferentiated vertigo patients" and the addition of MRI did not add any diagnostic accuracy in ED management. Using the physical examination findings effectively to make a specific diagnosis may reduce misdiagnosis and improve resource utilization.

Guidelines for reasonable and appropriate care in the emergency department 3 (GRACE-3): Acute dizziness and vertigo in the emergency department

This third Guideline for Reasonable and Appropriate Care in the Emergency Department (GRACE-3) from the Society for Academic Emergency Medicine is on the topic adult patients with acute dizziness and vertigo in the emergency department (ED). A multidisciplinary guideline panel applied the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach to assess the certainty of evidence and strength of recommendations regarding five questions for adult ED patients with acute dizziness of less than 2 weeks' duration. The intended population is adults presenting to the ED with acute dizziness or vertigo. The panel derived 15 evidence-based recommendations based on the timing and triggers of the dizziness but recognizes that alternative diagnostic approaches exist, such as the STANDING protocol and nystagmus examination in combination with gait unsteadiness or the presence of vascular risk factors. As an overarching recommendation, (1) emergency clinicians should receive training in bedside physical examination techniques for patients with the acute vestibular syndrome (AVS; HINTS) and the diagnostic and therapeutic maneuvers for benign paroxysmal positional vertigo (BPPV; Dix-Hallpike test and Epley maneuver). To help distinguish central from peripheral causes in patients with the AVS, we recommend: (2) use HINTS (for clinicians trained in its use) in patients with nystagmus, (3) use finger rub to further aid in excluding stroke in patients with nystagmus, (4) use severity of gait unsteadiness in patients without nystagmus, (5) do not use brain computed tomography (CT), (6) do not use routine magnetic resonance imaging (MRI) as a first-line test if a clinician trained in HINTS is available, and (7) use MRI as a confirmatory test in patients with central or equivocal HINTS examinations. In patients with the spontaneous episodic vestibular syndrome: (8) search for symptoms or signs of cerebral ischemia, (9) do not use CT, and (10) use CT angiography or MRI angiography if there is concern for transient ischemic attack. In patients with the triggered (positional) episodic vestibular syndrome, (11) use the Dix-Hallpike test to diagnose posterior canal BPPV (pc-BPPV), (12) do not use CT, and (13) do not use MRI routinely, unless atypical clinical features are present. In patients diagnosed with vestibular neuritis, (14) consider short-term steroids as a treatment option. In patients diagnosed with pc-BPPV, (15) treat with the Epley maneuver. It is clear that as of 2023, when applied in routine practice by emergency clinicians without special training, HINTS testing is inaccurate, partly due to use in the wrong patients and partly due to issues with its interpretation. Most emergency physicians have not received training in use of HINTS. As such, it is not standard of care, either in the legal sense of that term ("what the average physician would do in similar circumstances") or in the common parlance sense ("the standard action typically used by physicians in routine practice").

Increased Risk of Injury in Ménière's Disease and Effects of Treatment: Population-Based Retrospective Cohort Study

OBJECTIVE

To investigate the risk of injury in patients with Ménière's disease (MD) and the effects of treatment.

STUDY DESIGN

Population-based retrospective cohort study.

SETTING

Data were collected from the Longitudinal Health Insurance Database 2005, containing the information of 2 million randomly selected individuals in Taiwan.

METHODS

We enrolled 90,481 patients with newly diagnosed MD between 2000 and 2017 and 361,924 matched individuals without MD. The study outcomes were diagnoses of all-cause injuries. The Kaplan-Meier method was used to determine the cumulative incidence rates of injury in the MD and non-MD cohorts, and a log-rank test was used to analyze the differences between the cohorts. Cox proportional hazards models were used to calculate the 18-year hazard ratios of each cohort.

RESULTS

A total of 80,151 patients were diagnosed with injuries during the follow-up period: 24,031 and 56,120 from the MD and non-MD cohorts, respectively. The adjusted hazard ratio (aHR) was 2.19 (95% CI, 2.16-2.35) after adjusting for demographic characteristics and comorbidities. Subgroup analysis revealed that MD was associated with an increased incidence of unintentional and intentional injuries (aHR, 2.24 [95% CI, 2.21-2.41] and 2.05 [95% CI, 2.01-2.19], respectively). Treatment with diuretics, antivertigo medications, or surgery did not reduce the risk of injury (aHR, 0.98 [95% CI, 0.59-1.54], 0.94 [95% CI, 0.58-1.50], and 0.99 [95% CI, 0.61-1.54]).

CONCLUSION

MD is independently associated with an increased risk of injuries. Medical or surgical treatment for MD does not reduce the risk of injury in patients with MD. Physicians should counsel patients with MD regarding preventive measures for avoiding subsequent injuries.

Impairment of attention network function in posterior circulation ischemia-evidence from the Attention Network Test

Objective

This study aimed to investigate the effect of posterior circulation ischemia (PCI) on attention network function and to determine whether PCI is holistic or selective attention network deficit and which attention network is affected.

Methods

Thirty-six PCI patients aged 30 to 75 were assessed using the Attention Network Test and the Mini-Mental State Examination (MMSE). There were no significant differences in age, sex, and education between PCI group and the control group (n = 32). All data were statistically analyzed by SPSS 23.0 software.

Result

There were no significant difference in the MMSE scores between the two groups. Compared with the control group, the PCI group had significantly shorter response time for alerting and orienting network. The executive control network response time was significantly longer in PCI group than in the control group. The overall mean response time was also significantly longer in PCI group than in normal control group. There was no significant difference in mean accuracy between the two groups.

Conclusion

The alerting, orienting, and executive control networks were significantly less efficient in PCI group than in the control group (P < 0.01). This indicates impaired attention network in PCI patients. Since transient nerve seizures caused by vertebrobasilar ischemia may precede posterior circulation stroke, early assessment of cognitive function in patients with PCI is particularly important, and ANT is an excellent tool for this assessment.

Deep learning in acute vertigo diagnosis

Recent advances in artificial intelligence are transforming healthcare and there are increasing efforts to apply these breakthroughs to the diagnosis of acute vertigo. Because the diagnosis of vertigo relies on the analysis of eye movements, there are several unique considerations that must be made when implementing deep learning approaches to vertigo. This review discusses the need for diagnostic aids for acute vertigo, the techniques used to preprocess eye movement data and adapt deep learning models to vertigo, and summarizes and analyzes all published models to date.

Short-term stroke risk after emergency department treat-and-release headache visit

OBJECTIVE

To evaluate whether patients discharged to home after an emergency department (ED) visit for headache face a heightened short-term risk of stroke.

BACKGROUND

Stroke hospitalizations that occur soon after ED visits for headache complaints may reflect diagnostic error.

METHODS

We conducted a retrospective cohort study using statewide administrative claims data for all ED visits and admissions at nonfederal hospitals in Florida 2005-2018 and New York 2005-2016. Using standard International Classification of Diseases (ICD) codes, we identified adult patients discharged to home from the ED (treat-and-release visit) with a benign headache diagnosis (cohort of interest) as well as those with a diagnosis of renal colic or back pain (negative controls). The primary study outcome was hospitalization within 30 days for stroke (ischemic or hemorrhagic) defined using validated ICD codes. We assess the relationship between index ED visit discharge diagnosis and stroke hospitalization adjusting for patient demographics and vascular comorbidities.

RESULTS

We identified 1,502,831 patients with an ED treat-and-release headache visit; mean age was 41 (standard deviation: 17) years and 1,044,520 (70%) were female. A total of 2150 (0.14%) patients with headache were hospitalized for stroke within 30 days. In adjusted analysis, stroke risk was higher after headache compared to renal colic (hazard ratio [HR]: 2.69; 95% confidence interval [CI]: 2.29-3.16) or back pain (HR: 4.0; 95% CI: 3.74-4.3). In the subgroup of 26,714 (1.78%) patients with headache who received brain magnetic resonance imaging at index ED visit, stroke risk was only slightly elevated compared to renal colic (HR: 1.47; 95% CI: 1.22-1.78) or back pain (HR: 1.49; 95% CI: 1.24-1.80).

CONCLUSION

Approximately 1 in 700 patients discharged to home from the ED with a headache diagnosis had a stroke in the following month. Stroke risk was three to four times higher after an ED visit for headache compared to renal colic or back pain.

Risk of Future Stroke in Patients with a Diagnosis of Peripheral Vertigo in the Emergency Department

BACKGROUND

We evaluated the temporal characteristics of stroke risks in the emergency department patients who had a diagnosis of peripheral vertigo. We also attempted to reveal the stroke risk factor among those with peripheral vertigo.

METHODS

This is a parallel group cohort study in a tertiary referral hospital. After assigning each of matched 4367 patients to the comparative set of peripheral vertigo and appendicitis-ureterolithiasis groups and each of matched 4911 to the comparative set of peripheral vertigo and ischemic stroke groups, we evaluated the relative stroke risk. In addition, to predict the individual stroke risk in patients with peripheral vertigo, any association between the demographic factors and stroke events was evaluated in the peripheral vertigo group.

RESULTS

The peripheral vertigo group had a higher stroke risk than the appendicitis-ureterolithiasis group (HR=1.73, 95% CI=1.18-2.55) but a lower risk than the ischemic stroke group (HR=0.30, 95% CI=0.24-0.37). The stroke risk of the peripheral vertigo group was just below that of small vessel stroke. The stroke risk of the peripheral vertigo group differed markedly by time: higher within seven days, moderate between seven days and one year, and diminished thereafter. Old age (>65), male gender, and diabetes mellitus were the risk factors for stroke in the peripheral vertigo group.

CONCLUSION

Patients with a diagnosis of peripheral vertigo in the ED showed a moderate future stroke risk so that requires a stroke preventive strategy tailored to the timing of symptom onset and individual risk.

Validation of a comprehensive diagnostic algorithm for patients with acute vertigo and dizziness

BACKGROUND

Vertigo and dizziness are common complaints in emergency departments and primary care, which pose major diagnostic challenges due to various underlying etiologies. Most supportive diagnostic algorithms concentrate on either identifying cerebrovascular events or diagnosing specific vestibular disorders or are restricted to specific patient subgroups.

METHODS

The study was conducted in the scope of the 'PoiSe' project (prevention, online feedback, and interdisciplinary therapy of acute vestibular syndromes by e-health). A three-level algorithm was developed according to international guidelines and scientific evidence addressing both, the detection of cerebrovascular events and the classification to non-vascular vestibular disorders (unilateral vestibulopathy, benign paroxysmal positional vertigo, vestibular paroxysmia, Menière's disease, vestibular migraine, functional dizziness). The algorithm was validated on a prospectively collected dataset of 407 patients with acute vertigo and dizziness presenting to the emergency department at LMU Munich.

RESULTS

The algorithm assigned 287 of 407 patients to the correct diagnosis, corresponding to an overall accuracy of 71%. Cerebrovascular events were identified with high sensitivity of 94%. The six most common vestibular disorders were classified with high specificity above 95%. Random forest identified the presence of a paresis, sensory loss, central ocular motor and vestibular signs (HINTS), and older age as the most important variables indicating a cerebrovascular event.

CONCLUSIONS

The proposed diagnostic algorithm can correctly classify the most common vestibular disorders based on a comprehensive set of key questions and clinical examinations. It is easily applied, not limited to subgroups, and might therefore be transferred to broad clinical settings such as primary health care.

Vascular vertigo and dizziness: Diagnostic criteria

This paper presents diagnostic criteria for vascular vertigo and dizziness as formulated by the Committee for the Classification of Vestibular Disorders of the Bárány Society. The classification includes vertigo/dizziness due to stroke or transient ischemic attack as well as isolated labyrinthine infarction/hemorrhage, and vertebral artery compression syndrome. Vertigo and dizziness are among the most common symptoms of posterior circulation strokes. Vascular vertigo/dizziness may be acute and prolonged (≥24 hours) or transient (minutes to  < 24 hours). Vascular vertigo/dizziness should be considered in patients who present with acute vestibular symptoms and additional central neurological symptoms and signs, including central HINTS signs (normal head-impulse test, direction-changing gaze-evoked nystagmus, or pronounced skew deviation), particularly in the presence of vascular risk factors. Isolated labyrinthine infarction does not have a confirmatory test, but should be considered in individuals at increased risk of stroke and can be presumed in cases of acute unilateral vestibular loss if accompanied or followed within 30 days by an ischemic stroke in the anterior inferior cerebellar artery territory. For diagnosis of vertebral artery compression syndrome, typical symptoms and signs in combination with imaging or sonographic documentation of vascular compromise are required.

A Dynamic Nomogram to Predict the Risk of Stroke in Emergency Department Patients With Acute Dizziness

Objective

To develop a risk prediction tool for acute ischemic stroke (AIS) for patients presenting to the emergency department (ED) with acute dizziness/vertigo or imbalance.

Method

A prospective, multicenter cohort study was designed, and adult patients presenting with dizziness/vertigo or imbalance within 14 days were consecutively enrolled from the EDs of 4 tertiary hospitals between August 10, 2020, and June 10, 2021. Stroke was diagnosed by CT or MRI performed within 14 days of symptom onset. Participants were followed-up for 30 days. The least absolute shrinkage and selection operator (LASSO) logistic regression analysis was conducted to extract predictive factors that best identified patients at high risk of stroke to establish a prediction model. Model discrimination and calibration were assessed and its prediction performance was compared with the age, blood pressure, clinical features, duration, and diabetes (ABCD2) score, nystagmus scheme, and finger to nose test.

Results

In this study, 790 out of 2,360 patients were enrolled {median age, 60.0 years [interquartile range (IQR), 51–68 years]; 354 (44.8%) men}, with complete follow-up data available. AIS was identified in 80 patients. An online web service tool (https://neuroby.shinyapps.io/dynnomapp/) was developed for stroke risk prediction, including the variables of sex, trigger, isolated symptom, nausea, history of brief dizziness, high blood pressure, finger to nose test, and tandem gait test. The model exhibited excellent discrimination with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.889 (95% CI: 0.855–0.923), compared with the ABCD2 score, nystagmus scheme, and finger to nose test [0.712 (95% CI, 0.652–0.771), 0.602 (95% CI, 0.556–0.648), and 61.7 (95% CI, 0.568–0.666) respectively].

Conclusion

Our new prediction model exhibited good performance and could be useful for stroke identification in patients presenting with dizziness, vertigo, or imbalance. Further externally validation study is needed to increase the strength of our findings.

Capturing vertigo in the emergency room: three tools to double the rate of diagnosis

OBJECTIVE

Many patients attending the emergency room (ER) with vertigo, leave without a diagnosis. We assessed whether the three tools could improve ER diagnosis of vertigo.

METHODS

A prospective observational study was undertaken on 539 patients presenting to ER with vertigo. We used three tools: a structured-history and examination, nystagmus video-oculography (VOG) in all patients, additional video head-impulse testing (vHIT) for acute-vestibular-syndrome (AVS).

RESULTS

In the intervention-group (n = 424), case-history classified AVS in 34.9%, episodic spontaneous-vertigo (ESV 32.1%), and episodic positional-vertigo (EPV 22.6%). In AVS, we employed "Quantitative-HINTS plus" (Head-Impulse, Nystagmus and Test-of-Skew quantified by vHIT and VOG, audiometry) to identify vestibular-neuritis (VN) and stroke (41.2 and 31.1%). vHIT gain ≤ 0.72, catch-up saccade amplitude > 1.4^○, saccade-frequency > 154%, and unidirectional horizontal-nystagmus, separated stroke from VN with 93.1% sensitivity and 88.5% specificity. In ESV, 66.2 and 14% were diagnosed with vestibular migraine and Meniere's Disease by using history and audiometry. Horizontal-nystagmus velocity was lower in migraine 0.4 ± 1.6^○/s than Meniere's 5.7 ± 5.5^○/s (p < 0.01). In EPV, benign positional vertigo (BPV) was identified in 82.3% using VOG. Paroxysmal positional-nystagmus lasting < 60 s separated BPV from non-BPV with 90% sensitivity and 100% specificity. In the control group of ER patients undergoing management-as-usual (n = 115), diagnoses included BPV (38.3%) and non-specific vertigo (41.7%). Unblinded assessors reached a final diagnosis in 90.6 and 30.4% of the intervention and control groups. Blinded assessors provided with the data gathered from each group reached a diagnosis in 86.3 and 41.1%.

CONCLUSION

Three tools: a structured-assessment, vHIT and VOG doubled the rate of diagnosis in the ER.

Differentiating central from peripheral causes of acute vertigo in an emergency setting with the HINTS, STANDING, and ABCD2 tests: A diagnostic cohort study

BACKGROUND

Diagnosing stroke in dizzy patients remains a challenge in emergency medicine. The accuracy of the neuroophthalmologic examination HINTS performed by emergency physicians (EPs) is unknown. Our objective was to determine the accuracy of the HINTS examination performed by trained EPs for diagnosing central cause of acute vertigo and unsteadiness and to compare it with another bedside clinical tool, STANDING, and with the history-based score ABCD2.

METHODS

This was a prospective diagnostic cohort study among patients with isolated vertigo and unsteadiness seen in a single emergency department (ED). Trained EPs performed HINTS and STANDING tests blinded to attending physicians. ABCD2 ≥ 4 was used as the threshold and was calculated retrospectively. The criterion standard was diffusion-weighted brain magnetic resonance imaging (MRI). Peripheral diagnoses were established by a normal MRI, and etiologies were further refined by an otologic examination.

RESULTS

We included 300 patients of whom 62 had a central lesion on neuroimaging including 49 strokes (79%). Of the 238 peripheral diagnoses, 159 were vestibulopathies, mainly benign paroxysmal positional vertigo (40%). HINTS and STANDING tests reached high sensitivities at 97% and 94% and NPVs at 99% and 98%, respectively. The ABCD2 score failed to predict half of central vertigo cases and had a sensitivity of 55% and a NPV of 87%. The STANDING test was more specific and had a better positive predictive value (PPV; 75% and 49%, respectively; positive likelihood ratio [LR+] = 3.71, negative likelihood ratio [LR-] = 0.09) than the HINTS test (67% and 44%, respectively; LR+ = 2.96, LR- = 0.04). The ABCD2 score was specific (82%, LR+ = 3.04, LR- = 0.56) but had a very low PPV (44%).

CONCLUSIONS

In the hands of EPs, HINTS and STANDING tests outperformed ABCD2 in identifying central causes of vertigo. For diagnosing peripheral disorders, the STANDING algorithm is more specific than the HINTS test. HINTS and STANDING could be useful tools saving both time and costs related to unnecessary neuroimaging use.

Ischemic stroke mimics: A comprehensive review

BACKGROUND

Ischemic stroke is the leading cause of disability and one of the leading causes of death. Ischemic stroke mimics (SMs) can account for a noteble number of diagnosed acute strokes and even can be thrombolyzed.

METHODS

The aim of our comprehensive review was to summarize the findings of different studies focusing on the prevalence, type, risk factors, presenting symptoms, and outcome of SMs in stroke/thrombolysis situations.

RESULTS

Overall, 61 studies were selected with 62.664 participants. Ischemic stroke mimic rate was 24.8% (15044/60703). Most common types included peripheral vestibular dysfunction in 23.2%, toxic/metabolic in 13.2%, seizure in 13%, functional disorder in 9.7% and migraine in 7.76%. Ischemic stroke mimic have less vascular risk factors, younger age, female predominance, lower (nearly normal) blood pressure, no or less severe symptoms compared to ischemic stroke patients (p < 0.05 in all cases). 61.7% of ischemic stroke patients were thrombolysed vs. 26.3% among SMs (p < 0.001). (p < 0.001). Overall intracranial hemorrhage was reported in 9.4% of stroke vs. 0.7% in SM patients (p < 0.001). Death occurred in 11.3% of stroke vs 1.9% of SM patients (p < 0.001). Excellent outcome was (mRS 0-1) was reported in 41.8% ischemic stroke patients vs. 68.9% SMs (p < 0.001). Apart from HINTS manouvre or Hoover sign there is no specific method in the identification of mimics. MRI DWI or perfusion imaging have a role in the setup of differential diagnosis, but merit further investigation.

CONCLUSION

Our article is among the first complex reviews focusing on ischemic stroke mimics. Although it underscores the safety of thrombolysis in this situation, but also draws attention to the need of patient evaluation by physicians experienced in the diagnosis of both ischemic stroke and SMs, especially in vertigo, headache, seizure and conversional disorders.

Statistical insights for crude-rate-based operational measures of misdiagnosis-related harms

In longitudinal event data, a crude rate is a simple quantification of the event rate, defined as the number of events during an evaluation window, divided by the at-risk population size at the beginning or mid-time point of that window. The crude rate recently received revitalizing interest from medical researchers who aimed to improve measurement of misdiagnosis-related harms using administrative or billing data by tracking unexpected adverse events following a "benign" diagnosis. The simplicity of these measures makes them attractive for implementation and routine operational monitoring at hospital or health system level. However, relevant statistical inference procedures have not been systematically summarized. Moreover, it is unclear to what extent the temporal changes of the at-risk population size would bias analyses and affect important conclusions concerning misdiagnosis-related harms. In this article, we present statistical inference tools for using crude-rate based harm measures, as well as formulas and simulation results that quantify the deviation of such measures from those based on the more sophisticated Nelson-Aalen estimator. Moreover, we present results for a generalized multibin version of the crude rate, for which the usual crude rate is a single-bin special case. The generalized multibin crude rate is more straightforward to compute than the Nelson-Aalen estimator and can reduce potential biases of the single-bin crude rate. For studies that seek to use multibin measures, we provide simulations to guide the choice regarding number of bins. We further bolster these results using a worked example of stroke after "benign" dizziness from a large data set.

A Nationwide Population-Based Study on the Association between Land Transport Accident and Peripheral Vestibular Disorders

This case–control study aimed to investigate the association of peripheral vestibular disorders (PVD) with subsequent land transport accidents. Data for this study were obtained from Taiwan’s National Health Insurance (NHI) dataset. We retrieved 8704 subjects who were newly found to have land transport accidents as cases. Their diagnosis date was used as their index date. Controls were identified by propensity score matching (one per case, n = 8704 controls) from the NHI dataset with their index date being the date of their first health service claim in 2017. Multiple logistic regressions were performed to calculate the prior PVD odds ratio of cases vs. controls. We found that 2.36% of the sampled patients had been diagnosed with PVD before the index date, 3.37% among cases and 1.36% among controls. Chi-square test revealed that there was a significant association between land transport accident and PVD (p < 0.001). Furthermore, multiple logistic regression analysis suggested that cases were more likely to have had a prior PVD diagnosis when compared to controls (OR = 2.533; 95% CI = 2.041–3.143; p < 0.001). After adjusting for age, gender, hypertension, diabetes, coronary heart disease, and hyperlipidemia, cases had a greater tendency to have a prior diagnosis of PVD than controls (OR = 3.001, 95% CI = 2.410–3.741, p < 0.001). We conclude that patients with PVD are at twofold higher odds for land transport accidents.

Predicting value of fibrinogen in identifying cerebrovascular ischemic events in patients with dizziness/vertigo

PURPOSE

Dizziness and vertigo are caused by multiple etiologies, including cerebrovascular ischemic events. However, identifying cerebrovascular ischemic events as a cause of dizziness and vertigo remains a challenge. We tried to assess the value of fibrinogen (FIB) in identifying of cerebral ischemic event in patients with dizziness/vertigo.

METHODS

The study enrolled patients with dizziness/vertigo presented within 72 h in a tertiary hospital. The plasma FIB levels were measured in all participants. According to the final diagnosis, participants were divided into cerebral ischemic events group and non-cerebrovascular diseases group. Multivariate logistic regression was performed to explore the association between FIB and cerebral ischemic events. The receiver operating characteristic curve was performed, and the nomogram was constructed to evaluate the overall prediction ability of FIB in cerebral ischemic event.

RESULTS

A total of 298 participants were enrolled in our study, of 126 cerebral ischemic events patients. Multivariate logistic regression analysis showed that FIB was independently associated with cerebral ischemic event in patients with dizziness (OR = 1.84, 95%CI [1.15, 2.92], p = 0.010). The cut-off value of FIB in predicting cerebral ischemic event was 2.43 g/L (AUC = 0.658). The nomogram showed that higher FIB level was associated with a greater risk of cerebral ischemic event (C-index = 0.800).

CONCLUSIONS

Our study suggested that FIB may be a useful biochemical parameter for identifying cerebral ischemic event in patients with dizziness/vertigo.

[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.

Diagnostic Accuracy of the HINTS Exam in an Emergency Department: A Retrospective Chart Review

INTRODUCTION

The HINTS exam is a series of bedside ocular motor tests designed to distinguish between central and peripheral causes of dizziness in patients with continuous dizziness, nystagmus, and gait unsteadiness. Previous studies, where the HINTS exam was performed by trained specialists, have shown excellent diagnostic accuracy. Our objective was to assess the diagnostic accuracy of the HINTS exam as performed by emergency physicians on patients presenting to the emergency department (ED) with a primary complaint of vertigo or dizziness.

METHODS

A retrospective cohort study was performed using data from patients who presented to a tertiary care ED between September 2014 and March 2018 with a primary complaint of vertigo or dizziness. Patient characteristics of those who received the HINTS exam were assessed along with sensitivity and specificity of the test to rule out a central cause of stroke.

RESULTS

A total of 2,309 patients met criteria for inclusion in the study. Physician uptake of the HINTS exam was high, with 450 (19.5%) dizzy patients receiving all or part of the HINTS. A large majority of patients (96.9%) did not meet criteria for receiving the test as described in validation studies; most often this was because patients lacked documentation of nystagmus or described their symptoms as intermittent. In addition, many patients received both HINTS and Dix-Hallpike exams, which are intended for use in mutually exclusive patient populations. In no case was dizziness due to a central cause identified using the HINTS exam.

CONCLUSIONS

Our results suggest that despite widespread use of the HINTS exam in our ED, its diagnostic value in that setting was limited. The test was frequently used in patients who did not meet criteria to receive the HINTS exam (i.e., continuous vertigo, nystagmus, and unsteady gait). Additional training of emergency physicians may be required to improve test sensitivity and specificity.

Episodic Spontaneous Dizziness

PURPOSE OF REVIEW

Conditions causing recurrent spontaneous episodes of dizziness or vertigo span several medical specialties, making it challenging for clinicians to gain confidence in evaluating and managing the spectrum of episodic vestibular disorders. Patients are often asymptomatic and have normal examinations at the time of evaluation. Thus, diagnosis depends heavily on eliciting key features from the history. Overreliance on symptom quality descriptions commonly leads to misdiagnosis. The goal of this article is to provide the reader with a straightforward approach to the diagnosis and management of conditions that cause episodic spontaneous dizziness.

RECENT FINDINGS

Consensus diagnostic criteria have been established for vestibular migraine, Ménière disease, vestibular paroxysmia, and hemodynamic orthostatic dizziness/vertigo. Vertigo has been recognized as a common symptom in vertebrobasilar ischemia, cardiogenic dizziness, and orthostatic hypotension. Treatment recommendations for vestibular migraine still lack high-quality evidence, but controlled trials are occurring.

SUMMARY

The evaluation should start with a detailed description of the episodes from the patient and any observers. Rather than focusing first on whether the symptom quality is most consistent with vertigo, dizziness, lightheadedness, or unsteadiness, the clinician should clarify the timing (episode frequency and duration), possible triggers or circumstances (eg, position changes, upright posture), and accompanying symptoms. History should identify any auditory symptoms, migraine features, posterior circulation ischemic symptoms, vascular risk factors, clues for anxiety, and potentially relevant medications. Carefully selected testing can help secure the diagnosis, but excessive and indiscriminate testing can lead to more confusion. Treatments for these conditions are vastly different, so an accurate diagnosis is critical.

Increased Risk of Injury Following a Diagnosis of Vertigo: A Population-based Study

BACKGROUND

This study aimed to evaluate whether peripheral vestibular disorders (PVD) are associated with subsequent injury.

METHODS

Data for this follow-up study were retrieved from the Taiwan's National Health Insurance (NHI) Dataset. A total of 251,355 patients with newly diagnosed PVD during January 2015 to December 2016 was identified as the study cohort, the diagnosis date being their index date. Comparison patients were identified by propensity score-matching (one per case, n = 251,355 controls) from the remaining NHI beneficiaries in 2015 with their index date being the date of their first health service claim in 2015. We tracked each subject's claims history for 1 year from the index date to identify those who suffered an injury. Cox proportional hazards regressions were performed to calculate the injury hazard ratio of cases versus controls.

RESULTS

The incidence of injury during 1-year follow-up was 128.6 (95% CI = 127.6-129.5) per 1,000 person-years, 158.2 (95% CI = 156.8-159.6) and 97.5 (95% CI = 96.3-98.7) among the study and comparison cohorts, respectively. After adjusting for demographic variables, the hazard ratio (HR) for injury during 1-year was 1.663 (95% CI: 1.636-1.690) for cases relative to controls.

CONCLUSIONS

Patients with PVD were at a higher risk for a wide range of injuries, most of all, joint dislocation and sprain.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:1633-1638, 2021.

Patient Harm Due to Diagnostic Error of Neuro-Ophthalmologic Conditions

PURPOSE

To prospectively examine diagnostic error of neuro-ophthalmic conditions and resultant harm at multiple sites.

DESIGN

Prospective, cross-sectional study.

PARTICIPANTS

A total of 496 consecutive adult new patients seen at 3 university-based neuro-ophthalmology clinics in the United States in 2019 to 2020.

METHODS

Collected data regarding demographics, prior care, referral diagnosis, final diagnosis, diagnostic testing, treatment, patient disposition, and impact of the neuro-ophthalmologic encounter. For misdiagnosed patients, we identified the cause of error using the Diagnosis Error Evaluation and Research (DEER) taxonomy tool and whether the patient experienced harm due to the misdiagnosis.

MAIN OUTCOME MEASURES

The primary outcome was whether patients who were misdiagnosed before neuro-ophthalmology referral experienced harm as a result of the misdiagnosis. Secondary outcomes included appropriateness of referrals, misdiagnosis rate, interventions undergone before referral, and the primary type of diagnostic error.

RESULTS

Referral diagnosis was incorrect in 49% of cases. A total of 26% of misdiagnosed patients experienced harm, which could have been prevented by earlier referral to neuro-ophthalmology in 97%. Patients experienced inappropriate laboratory testing, diagnostic imaging, or treatment before referral in 23%, with higher rates for patients misdiagnosed before referral (34% of patients vs. 13% with a correct referral diagnosis, P < 0.0001). Seventy-six percent of inappropriate referrals were misdiagnosed, compared with 45% of appropriate referrals (P < 0.0001). The most common reasons for referral were optic neuritis or optic neuropathy (21%), papilledema (18%), diplopia or cranial nerve palsies (16%), and unspecified vision loss (11%). The most common sources of diagnostic error were the physical examination (36%), generation of a complete differential diagnosis (24%), history taking (24%), and use or interpretation of diagnostic testing (13%). In 489 of 496 patients (99%), neuro-ophthalmology consultation (NOC) affected patient care. In 2% of cases, neuro-ophthalmology directly saved the patient's life or vision; in an additional 10%, harmful treatment was avoided or appropriate urgent referral was provided; and in an additional 48%, neuro-ophthalmology provided a diagnosis and direction to the patient's care.

CONCLUSIONS

Misdiagnosis of neuro-ophthalmic conditions, mismanagement before referral, and preventable harm are common. Early appropriate referral to neuro-ophthalmology may prevent patient harm.

The use and misuse of the Dix-Hallpike test in the emergency department

OBJECTIVES

A simple bedside test, the Dix-Hallpike test (DHT), can reliably diagnose benign paroxysmal positional vertigo (BPPV) in patients with acute onset dizziness or vertigo. We evaluated patterns of DHT use by emergency physicians in patients presenting with dizziness and vertigo. Our objective was to assess the frequency and clinically appropriate use of the DHT in an emergency department.

METHODS

A health records review was performed using data from patients who presented to a tertiary care emergency department between September 2014 and March 2018 with a primary complaint of vertigo or dizziness. Patient records were reviewed for documentation of symptoms consistent with BPPV and DHT usage.

RESULTS

A total of 2309 patients met inclusion criteria. Of all dizzy patients who had complete documentation of signs and symptoms consistent with BPPV, 53% were assessed with a DHT. Of 469 patients who received a DHT, 134 (29%) of tests were done on patients who had documentation of at least one characteristic that was inconsistent with a diagnosis of BPPV. Eight patients who received a DHT were ultimately diagnosed with a central cause for their vertigo.

CONCLUSIONS

The DHT is both underutilized and frequently applied to patients whose symptoms are not consistent with BPPV. This may result in prolonged patient discomfort and increased resource utilization, as well as increasing the risk of misdiagnosing central vertigo.

Diagnostic Error of Neuro-ophthalmologic Conditions: State of the Science

BACKGROUND

Diagnostic error is prevalent and costly, occurring in up to 15% of US medical encounters and affecting up to 5% of the US population. One-third of malpractice payments are related to diagnostic error. A complex and specialized diagnostic process makes neuro-ophthalmologic conditions particularly vulnerable to diagnostic error.

EVIDENCE ACQUISITION

English-language literature on diagnostic errors in neuro-ophthalmology and neurology was identified through electronic search of PubMed and Google Scholar and hand search.

RESULTS

Studies investigating diagnostic error of neuro-ophthalmologic conditions have revealed misdiagnosis rates as high as 60%-70% before evaluation by a neuro-ophthalmology specialist, resulting in unnecessary tests and treatments. Correct performance and interpretation of the physical examination, appropriate ordering and interpretation of neuroimaging tests, and generation of a differential diagnosis were identified as pitfalls in the diagnostic process. Most studies did not directly assess patient harms or financial costs of diagnostic error.

CONCLUSIONS

As an emerging field, diagnostic error in neuro-ophthalmology offers rich opportunities for further research and improvement of quality of care.

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.

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.

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.

Risk of injury after emergency department visit for acute peripheral vertigo: a matched-cohort study

Objective

Peripheral vertigo is one of the most common causes of the emergency department (ED) visits. It can impair balance and might predispose patients to injuries after discharge. The purpose of this study was to determine whether peripheral vertigo is associated with an increased risk of trauma.

Methods

This matched-cohort study used the nationally representative dataset of de-identified claim information of 1 million randomly sampled individuals from a real Korean population, from 2002 to 2013. The exposure cohort included patients who visited EDs for new-onset peripheral vertigo without prior or concurrent injury. Each patient was randomly matched to five unexposed individuals (also without previous injury) by incidence density sampling. The primary outcome was a new injury within 1 year. The secondary outcomes were various injury subtypes. The time-dependent effect of the exposure was modeled using the extended Cox model. Age, sex, comorbidities, and household income level were included as covariates.

Results

A total of 776 and 3,880 individuals were included as the exposure and comparison cohorts, respectively. The risks of trunk injury and upper extremity injury were significantly higher in the exposure cohort. Extended Cox models with multivariable adjustment showed significantly increased risk for up to 1 year, with the first 1-month; 1 month to 3 months; and 3 months to 1 year hazard ratios of 5.23 (95% confidence interval [CI], 2.83–9.64); 1.50 (95% CI, 1.02–2.20); and 1.37 (95% CI, 1.11–1.68), respectively.

Conclusion

Patients visiting EDs for acute peripheral vertigo are at a higher risk of a new injury for up to a year.

Efficacy and safety of acupuncture for posterior circulation ischemic vertigo: A protocol for systematic review and meta-analysis

BACKGROUND

Posterior circulation ischemic vertigo (PCIV) is one of the most complaint symptoms in clinical, and is associated with high risk of recurrence. Current studies show that acupuncture has therapeutic effect on releasing symptom as well as improving the blood flow of posterior circulation. In this review, we aim to assess the efficacy and safety of acupuncture for PCIV.

METHODS

Literature of clinical randomized control trials regarding acupuncture for PCIV published before August of 2020 will be searched in databases, including 5 English databases and 4 Chinese databases. For the included studies, methodological quality will be assessed according to Cochrane Risk of Bias Tool, and evidence quality will be evaluated with Grading of Recommendations Assessment, Development and Evaluation guidelines. Data analysis will be performed using Review Manager Software.

RESULTS

The primary outcomes involve changes of PCIV symptoms and blood flow velocity of vertebrobasilar. The secondary outcomes include Barthel Index, National Institute of Health Stroke Scale, clinical effectiveness, and adverse reactions.

CONCLUSION

Based on current clinical studies, this systematic review and meta-analysis will provide evidence-based basis for the efficacy and safety of acupuncture in treating PCIV.

TRIAL REGISTRATION

The protocol for this review has been registered in the INPLASY network (Registration number: INPLASY202070116).

Association between Pregnancy and Cervical Artery Dissection

OBJECTIVE

We wanted to determine whether pregnancy is associated with cervical artery dissection.

METHODS

We performed a case-control study using claims data from all nonfederal emergency departments and acute care hospitals in New York and Florida between 2005 and 2015. Cases were women 12-42 years of age hospitalized with cervical artery dissection, defined using validated diagnosis codes for carotid/vertebral artery dissection. Controls were women 12-42 years of age with a primary diagnosis of renal colic. Cases and controls were matched 1:1 on age, race, insurance, income, state, and visit year. The exposure variable was pregnancy, defined as labor and delivery within 90 days before or 6 months after the index visit. Logistic regression was used to compare the odds of pregnancy between cases and controls. We performed a secondary cohort-crossover study comparing the risk of cervical artery dissection during pregnancy versus the same time period 1 year later.

RESULTS

Pregnancy was twice as common among 826 women with cervical artery dissection compared with the 826 matched controls with renal colic (odds ratio, 2.5; 95% confidence interval [CI], 1.3-4.7). In our secondary analysis, pregnancy was associated with a higher risk of cervical artery dissection (incidence rate ratio [IRR], 2.2; 95% CI, 1.3-3.5), with the heightened risk limited to the postpartum period (IRR, 5.5; 95% CI, 2.6-11.7).

INTERPRETATION

Pregnancy, specifically the postpartum period, was associated with hospitalization for cervical artery dissection. Although these findings might in part reflect ascertainment bias, our results suggest that arterial dissection is one mechanism by which pregnancy can lead to stroke. ANN NEUROL 2020;88:596-602.

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.

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.

Associations between cerebrovascular risk factors and parkinson disease

OBJECTIVE

To determine whether cerebrovascular risk factors are associated with subsequent diagnoses of Parkinson disease, and whether these associations are similar in magnitude to those with subsequent diagnoses of Alzheimer disease.

METHODS

This was a retrospective cohort study using claims data from a 5% random sample of Medicare beneficiaries from 2008 to 2015. The exposures were stroke, atrial fibrillation, coronary disease, hyperlipidemia, hypertension, sleep apnea, diabetes mellitus, heart failure, peripheral vascular disease, chronic kidney disease, chronic obstructive pulmonary disease, valvular heart disease, tobacco use, and alcohol abuse. The primary outcome was a new diagnosis of idiopathic Parkinson disease. The secondary outcome was a new diagnosis of Alzheimer disease. Marginal structural Cox models adjusting for time-dependent confounding were used to characterize the association between exposures and outcomes. We also evaluated the association between cerebrovascular risk factors and subsequent renal colic (negative control).

RESULTS

Among 1,035,536 Medicare beneficiaries followed for a mean of 5.2 years, 15,531 (1.5%) participants were diagnosed with Parkinson disease and 81,974 (7.9%) were diagnosed with Alzheimer disease. Most evaluated cerebrovascular risk factors, including prior stroke (hazard ratio = 1.55; 95% confidence interval = 1.39-1.72), were associated with the subsequent diagnosis of Parkinson disease. The magnitudes of these associations were similar, but attenuated, to the associations between cerebrovascular risk factors and Alzheimer disease. Confirming the validity of our analytical model, most cerebrovascular risk factors were not associated with the subsequent diagnosis of renal colic.

INTERPRETATION

Cerebrovascular risk factors are associated with Parkinson disease, an effect comparable to their association with Alzheimer disease. ANN NEUROL 2019;86:572-581.

Diagnostic error and neuro-ophthalmology

PURPOSE OF REVIEW

This review summarizes the recent literature on diagnostic error relevant to the practice of neuro-ophthalmology, and evaluates the potential for increased access to neuro-ophthalmology to decrease rates of diagnostic error, thereby reducing medical harm and spending on unnecessary tests and treatments.

RECENT FINDINGS

Despite medical advances, current research continues to show alarmingly high rates of diagnostic error. Research into diagnostic error shows that many of these errors can be traced to cognitive errors. Recent studies on diagnostic problems relevant to neuro-ophthalmology, including studies of misdiagnosis of posterior communicating artery aneurysms, idiopathic intracranial hypertension, optic neuritis, and optic nerve sheath meningiomas, have identified major causes of diagnostic error in these conditions.

SUMMARY

Studies on diagnostic error in neuro-ophthalmologic conditions show that prior to evaluation by a neuro-ophthalmologist, patients may undergo unnecessary tests and treatments that are costly and potentially harmful. Further research on diagnostic error will inform better utilization of neuro-ophthalmologists as a resource to decrease diagnostic error.

Rear Admiral (Astronaut) Alan Shepard: Ménière's disease and the race to the moon

On May 5, 1961, Alan B. Shepard Jr. piloted the Freedom 7 craft into a suborbital flight to become the first American man in space. His promising astronautical career was soon scuttled by spells of dizziness and tinnitus later diagnosed as Ménière's disease, until William F. House-considered the father of neurotology and a pioneer in surgery for vestibular schwannomas-intervened. In 1968 House implanted an endolymphatic-subarachnoid shunt, which at the time was a virtually experimental procedure. Shepard's debilitating Ménière's disease was cured, but not quite in time for him to pilot the doomed Apollo 13 mission; he was reassigned to Apollo 14 and as a result would step foot on the moon on February 5, 1971. This historical vignette depicts the tale of how the career trajectories of Shepard and House-two notable figures in their respective fields-fatefully intersected.