A New Approach to the Diagnosis of Acute Dizziness in Adult Patients

Overlooked Carbamazepine Toxicity: A Diagnostic Pitfall in an Elderly Patient With Dizziness

Dizziness is a common chief complaint that often poses a diagnostic challenge. A 79-year-old man was initially misdiagnosed with peripheral vertigo based on normal neuroimaging but later developed altered consciousness and involuntary limb movements, ultimately revealing carbamazepine (CBZ) toxicity. This case highlights a critical diagnostic pitfall: prematurely attributing dizziness to peripheral vertigo without considering drug-induced syndromes. Although the potential role of concomitant amiodarone use remains uncertain, this case also underscores the importance of cautious CBZ dose escalation, serum level monitoring, and a thorough medication review. Recognizing CBZ toxicity as a mimicker of central vertigo is crucial for ensuring timely and accurate diagnosis, especially in elderly patients.

Distinguishing Peripheral from Central Causes of Dizziness and Vertigo without using HINTS or STANDING

Three validated diagnostic algorithms for diagnosing patients with acute onset dizziness or vertigo (HINTS, HINTS-plus and STANDING) exist. All are extremely accurate in distinguishing peripheral from central causes of dizziness when done by experienced clinicians. However, uptake of these diagnostic tools in routine emergency medicine practice has been sub-optimal, in part, due to clinicians' unease with the head impulse test, the most useful component contained of these algorithms. Use of these validated algorithms is the best way to accurately diagnose patients with acute dizziness. For clinicians who are unfamiliar with or uncomfortable performing or interpreting HINTS and STANDING, this article will suggest alternative approaches to help with accurate diagnosis of patients with acute dizziness or vertigo.

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.

Diagnostic accuracy of the physical examination in emergency department patients with acute vertigo or dizziness: A systematic review and meta-analysis for GRACE-3

BACKGROUND

History and physical examination are key features to narrow the differential diagnosis of central versus peripheral causes in patients presenting with acute vertigo. We conducted a systematic review and meta-analysis of the diagnostic test accuracy of physical examination findings.

METHODS

This study involved a patient-intervention-control-outcome (PICO) question: (P) adult ED patients with vertigo/dizziness; (I) presence/absence of specific physical examination findings; and (O) central (ischemic stroke, hemorrhage, others) versus peripheral etiology. Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) was assessed.

RESULTS

From 6309 titles, 460 articles were retrieved, and 43 met the inclusion criteria: general neurologic examination-five studies, 869 patients, pooled sensitivity 46.8% (95% confidence interval [CI] 32.3%-61.9%, moderate certainty) and specificity 92.8% (95% CI 75.7%-98.1%, low certainty); limb weakness/hemiparesis-four studies, 893 patients, sensitivity 11.4% (95% CI 5.1%-23.6%, high) and specificity 98.5% (95% CI 97.1%-99.2%, high); truncal/gait ataxia-10 studies, 1810 patients (increasing severity of truncal ataxia had an increasing sensitivity for central etiology, sensitivity 69.7% [43.3%-87.9%, low] and specificity 83.7% [95% CI 52.1%-96.0%, low]); dysmetria signs-four studies, 1135 patients, sensitivity 24.6% (95% CI 15.6%-36.5%, high) and specificity 97.8% (94.4%-99.2%, high); head impulse test (HIT)-17 studies, 1366 patients, sensitivity 76.8% (64.4%-85.8%, low) and specificity 89.1% (95% CI 75.8%-95.6%, moderate); spontaneous nystagmus-six studies, 621 patients, sensitivity 52.3% (29.8%-74.0%, moderate) and specificity 42.0% (95% CI 15.5%-74.1%, moderate); nystagmus type-16 studies, 1366 patients (bidirectional, vertical, direction changing, or pure torsional nystagmus are consistent with a central cause of vertigo, sensitivity 50.7% [95% CI 41.1%-60.2%, moderate] and specificity 98.5% [95% CI 91.7%-99.7%, moderate]); test of skew-15 studies, 1150 patients (skew deviation is abnormal and consistent with central etiology, sensitivity was 23.7% [95% CI 15%-35.4%, moderate] and specificity 97.6% [95% CI 96%-98.6%, moderate]); HINTS (head impulse, nystagmus, test of skew)-14 studies, 1781 patients, sensitivity 92.9% (95% CI 79.1%-97.9%, high) and specificity 83.4% (95% CI 69.6%-91.7%, moderate); and HINTS+ (HINTS with hearing component)-five studies, 342 patients, sensitivity 99.0% (95% CI 73.6%-100%, high) and specificity 84.8% (95% CI 70.1%-93.0%, high).

CONCLUSIONS

Most neurologic examination findings have low sensitivity and high specificity for a central cause in patients with acute vertigo or dizziness. In acute vestibular syndrome (monophasic, continuous, persistent dizziness), HINTS and HINTS+ have high sensitivity when performed by trained clinicians.

Diagnostic accuracy of neuroimaging in emergency department patients with acute vertigo or dizziness: A systematic review and meta-analysis for the Guidelines for Reasonable and Appropriate Care in the Emergency Department

BACKGROUND

Patients presenting to the emergency department (ED) with acute vertigo or dizziness represent a diagnostic challenge. Neuroimaging has variable indications and yield. We aimed to conduct a systematic review and meta-analysis of the diagnostic test accuracy of neuroimaging for patients presenting with acute vertigo or dizziness.

METHODS

An electronic search was designed following patient-intervention-control-outcome (PICO) question, (P) adult patients with acute vertigo or dizziness presenting to the ED; (I) Neuroimaging including Computed tomography (CT), CT Angiogram (CTA), Magnetic Resonance Imaging (MRI), Magnetic Resonance Angiogram (MRA), and Ultrasound (US); (C) MRI/clinical gold standard; (O) central causes (stroke, hemorrhage, tumor, others) versus peripheral causes of symptoms. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) was used to assess certainty of evidence in pooled estimates.

RESULTS

We included studies that reported diagnostic test accuracy. Articles were assessed in duplicated. From 6,309 titles, 460 articles were retrieved, and 12 included. Non-contrast CT scan: 6 studies, 771 patients, pooled sensitivity 28.5% (95%CI 14.4-48.5%, moderate certainty) and specificity 98.9% (95%CI 93.4-99.8%, moderate certainty). MRI: 5 studies, 943 patients, sensitivity 79.8% (CI 71.4-86.2%, high certainty) and specificity 98.8% (CI 96.2-100%, high certainty). CTA: 1 study, 153 patients, sensitivity 14.3% (CI 1.8-42.8%) and specificity 97.7% (CI 93.8-99.6%). CT had higher sensitivity than CTA (21.4% and 14.3%) for central etiology. MRA: 1 study, 24 patients, sensitivity 60.0% (CI 26.2-87.8%) and specificity 92.9% (CI 66.1-99.8%). US: 3 studies, 258 patients, sensitivity ranged from 30-53.6%, specificity from 94.9-100%.

CONCLUSION

Non-contrast CT has very low sensitivity and MRI will miss approximately one in five patients with stroke if imaging is obtained early after symptom onset. Neuroimaging should not be used as the only tool for ruling out stroke and other central causes in patients with acute dizziness or vertigo presenting to the ED.

A comparative study of two methods for treatment of benign paroxysmal positional vertigo in the emergency department

Introduction

Posterior canal benign paroxysmal positional vertigo (PC-BPPV) is considered the most common cause of peripheral vertigo in the emergency department (ED). Although the canalith repositioning maneuver (CRM) is the standard of care, the most effective method to deliver it in the ED has been poorly studied.

Objective

To compare two protocols of the Epley maneuver for the treatment of PC-BPPV.

Patients and methods

We prospectively recruited 101 patients with unilateral PC-BPPV on physical examination, randomizing them to either a single Epley maneuver (EM) (n = 46) or multiple maneuvers (n = 55) on the same visit. Measured outcomes included presence/absence of positional nystagmus, resolution of vertigo, and score on the dizziness handicap inventory (DHI) at follow-up evaluations. The DHI was stratified into mild (≤30) and moderate-severe (>30).

Results

Normalization of the Dix-Hallpike maneuver at day 5 was observed in 38% of the single EM group and 44.4% in the multiple EM group (p = 0.62). The DHI showed reduction from 42.2 (SD 18.4) to 31.9 (SD 23.7) in the single EM group and from 43.7 (SD 22.9) to 33.5 (SD 21.5) in the multiple EM group (p = 0.06). A higher number of patients improved from moderate-severe to mild DHI (p = 0.03) in the single EM group compared to the multi-EM group (p = 0.23).

Conclusion

There was no statistically significant difference between performing a single EM versus multiple EMs for treatment of PC-BPPV in the emergency department. The single EM approach is associated with shorter physical contact between patients and examiner, which is logically safer in a pandemic context.

Pitfalls in the Diagnosis of Posterior Circulation Stroke in the Emergency Setting

Posterior circulation stroke (PCS), caused by infarction within the vertebrobasilar arterial system, is a potentially life-threatening condition and accounts for about 20–25% of all ischemic strokes. Diagnosing PCS can be challenging due to the vast area of brain tissue supplied by the posterior circulation and, as a consequence, the wide range of—frequently non-specific—symptoms. Commonly used prehospital stroke scales and triage systems do not adequately represent signs and symptoms of PCS, which may also escape detection by cerebral imaging. All these factors may contribute to causing delay in recognition and diagnosis of PCS in the emergency context. This narrative review approaches the issue of diagnostic error in PCS from different perspectives, including anatomical and demographic considerations as well as pitfalls and problems associated with various stages of prehospital and emergency department assessment. Strategies and approaches to improve speed and accuracy of recognition and early management of PCS are outlined.

Long-Term Survival in 1,931 Patients With Dizziness: Disease- and Symptom-Specific Mortality

OBJECTIVE

To evaluate mortality among patients referred for suspected vestibular disorder and to examine whether specific symptoms or disorders predict long-term survival among patients with dizziness or vertigo.

STUDY DESIGN

Retrospective cohort study.

METHODS

This retrospective cohort study analyzed long-term survival data. Consecutive patients examined for suspected vestibular disease at an otolaryngology clinic completed a detailed questionnaire regarding symptoms and comorbidities.

RESULTS

The study included 1,931 patients. Their mean age (standard deviation) was 50.5 (16.5) years, and 60% were women. The mean follow-up period was 20.6 years (range, 15.3-27.5 years). The standardized mortality ratio for the entire cohort compared with the Norwegian age- and sex-matched population was 1.03 (95% confidence interval [CI]: 0.94-1.12), illustrating no difference in overall survival. Patients with a cerebrovascular cause of dizziness had higher mortality in adjusted Cox regression analyses (hazard ratio [HR] 1.56, 95% CI: 1.11-2.19), whereas patients reporting periodic or short attacks of dizziness had lower mortality (HR 0.62 [0.50-0.77] and 0.76 [0.63-0.93], respectively). Reported unsteadiness between dizziness attacks was associated with higher mortality with an HR of 1.30 (95% CI: 1.08-1.57).

CONCLUSION

This long-term study found comparable mortality rates between patients evaluated for suspected vestibular disorder and that of the general population. However, subgroup analyses showed reduced mortality in patients with periodic or short attacks of dizziness and increased mortality in patients with unsteadiness between attacks or cerebrovascular causes of dizziness. The time course of vestibular symptoms should be determined, and thorough evaluation including fall risk and comorbidities must be considered in patients with nonepisodic symptoms.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:E2031-E2037, 2021.

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.

Optic nerve sheath diameter as a predictor of acute cerebellar infarction in acute vertigo patients without brain computed tomography abnormalities

Background and objectives:

To date, no study has investigated the ability of optic nerve sheath diameter calculated from non-contrast brain computed tomography to predict acute cerebellar infarction in patients with acute vertigo. The aim of our study was to evaluate the predictive utility of optic nerve sheath diameter for diagnosing acute cerebellar infarction in patients with acute vertigo without computed tomography abnormalities.

Methods:

We retrospectively enrolled patients with acute vertigo without computed tomography abnormalities who underwent magnetic resonance imaging including diffusion-weighted imaging at our emergency department between January 2016 and December 2017. Two emergency physicians independently measured optic nerve sheath diameter at 3 mm (ONSD3) and 10 mm (ONSD10) behind the globe in each patient. Final magnetic resonance imaging reports with clinical progress notes were used as the reference standard. A multivariate logistic regression analysis, receiver operating characteristic curves, and intra-class correlation coefficients were calculated to estimate predictive value.

Results:

A total of 34 patients (16.1%) were diagnosed with acute infarction and 177 patients (83.9%) were diagnosed with peripheral vertigo. Mean ONSD3 ( p < 0.001) and ONSD10 ( p < 0.001) were independent predictive factors for distinguishing acute infarction and peripheral vertigo. ONSD3 (cut-off = 4.22 mm) had 100% (95% confidence interval = 89.7–100.0) sensitivity and 97.7% (95% confidence interval = 95.1–99.6) specificity with area under the receiver operating characteristic curve of 0.988 (95% confidence interval = 0.978–1.0), while ONSD10 (cut-off = 3.63 mm) had 100% (95% confidence interval = 89.7–100.0) sensitivity and 87.6% (95% confidence interval = 81.8–92.0) specificity with area under the receiver operating characteristic curve of 0.976 (95% confidence interval = 0.959–0.997). There were good inter- and intra-observer agreements for both sides of ONSD3 and ONSD10 (intra-class correlation coefficient range = 0.652–0.773).

Conclusion:

Optic nerve sheath diameter, in particular OSND3, is a feasible predictive marker for acute infarction in patients with acute vertigo without computed tomography abnormalities. This information can assist decision-making in ordering brain magnetic resonance imaging for the assessment of acute vertigo.

High-Risk Chief Complaints III: Neurologic Emergencies

A careful history and thorough physical examination are necessary in patients presenting with acute neurologic dysfunction. Patients presenting with headache should be screened for red-flag criteria that suggest a dangerous secondary cause warranting imaging and further diagnostic workup. Dizziness is a vague complaint; focusing on timing, triggers, and examination findings can help reduce diagnostic error. Most patients presenting with back pain do not require emergent imaging, but those with new neurologic deficits or signs/symptoms concerning for acute infection or cord compression warrant MRI. Delay to diagnosis and treatment of acute ischemic stroke is a frequent reason for medical malpractice claims.

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.

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.

Utility of Neutrophil-to-Lymphocyte Ratio (NLR) as a Predictor of Acute Infarction in New-Onset Acute Vertigo Patients Without Neurologic and Computed Tomography Abnormalities

BACKGROUND

Neutrophil-to-lymphocyte ratio (NLR) has been used as a predictive marker for various conditions. However, there are no previous studies about NLR as a prognostic marker for acute infarction.

OBJECTIVE

To evaluate the potential utility of NLR as a predictor of acute infarction in acute vertigo patients without neurologic and computed tomography (CT) abnormalities.

METHODS

We conducted a prospective, observational study in the Emergency Department (ED) between January 2015 and December 2016. All patients underwent physical examination, laboratory tests, CT, and magnetic resonance imaging (MRI). Results of the initial and follow-up MRI with clinical progress note were considered as the reference standard. Statistically, multivariate logistic regression analysis and receiver operating characteristic (ROC) curve were used.

RESULTS

Thirty-five (25.9%) patients were diagnosed with acute infarction and 100 (74.1%) patients were diagnosed with peripheral vertigo. Horizontal nystagmus (p = 0.03; odds ratio 0.22) and NLR (p = 0.03; odds ratio 5.4) were significant factors for the differential diagnosis of acute infarction and peripheral vertigo. NLR > 2.8 showed the greatest area under the ROC curve (AUC; 0.819), optimal sensitivity (85.7%), and specificity (78.0%). NLR > 1.4 showed the highest sensitivity (97.1%) and relatively low specificity (41%). The absence of horizontal nystagmus increased the specificity (81.0%) and AUC (0.844).

CONCLUSIONS

A combination of NLR > 2.8 and the absence of horizontal nystagmus is sufficiently specific for acute infarction in an ED patient with acute vertigo; thus, further testing with MRI is indicated. NLR < 2.8 by itself or combined with the presence of horizontal nystagmus is not sufficiently sensitive to rule out the need for further testing.

Differential Diagnosis of Vertigo in the Emergency Department: A Prospective Validation Study of the STANDING Algorithm

Objective

We investigated the reliability and accuracy of a bedside diagnostic algorithm for patients presenting with vertigo/unsteadiness to the emergency department.

Methods

We enrolled consecutive adult patients presenting with vertigo/unsteadiness at a tertiary hospital. STANDING, the acronym for the four-step algorithm we have previously described, based on nystagmus observation and well-known diagnostic maneuvers includes (1) the discrimination between SponTAneous and positional nystagmus, (2) the evaluation of the Nystagmus Direction, (3) the head Impulse test, and (4) the evaluation of equilibrium (staNdinG). Reliability of each step was analyzed by Fleiss’ K calculation. The reference standard (central vertigo) was a composite of brain disease including stroke, demyelinating disease, neoplasm, or other brain disease diagnosed by initial imaging or during 3-month follow-up.

Results

Three hundred and fifty-two patients were included. The incidence of central vertigo was 11.4% [95% confidence interval (CI) 8.2–15.2%]. The leading cause was ischemic stroke (70%). The STANDING showed a good reliability (overall Fleiss K 0.83), the second step showing the highest (0.95), and the third step the lowest (0.74) agreement. The overall accuracy of the algorithm was 88% (95% CI 85–88%), showing high sensitivity (95%, 95% CI 83–99%) and specificity (87%, 95% CI 85–87%), very high-negative predictive value (99%, 95% CI 97–100%), and a positive predictive value of 48% (95% CI 41–50%) for central vertigo.

Conclusion

Using the STANDING algorithm, non-sub-specialists achieved good reliability and high accuracy in excluding stroke and other threatening causes of vertigo/unsteadiness.