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

Nationwide Prevalence of Video Head Impulse Test Abnormality and its Risk Factors in South Korea

OBJECTIVE

To identify the prevalence of and relevant information for video head impulse test (vHIT) abnormality in a large population.

STUDY DESIGN

A cross-sectional design.

SETTING

Korean National Health and Nutrition Examination Survey, 2021.

METHODS

The sample was representative of the Korean population, with 2237 participants aged ≥40 years. A vHIT was performed to evaluate vestibular function. The vestibulo-ocular reflex (VOR) gain and the presence of reproducible catch-up saccades was assessed in a vHIT. Participants also completed questionnaires for demographics, socioeconomic status, and basic information regarding systemic diseases and dizziness and underwent hearing tests with automated pure-tone audiometry.

RESULTS

The prevalence of vHIT abnormality was 22.5%, with unilateral (14.3%) being more common than bilateral (8.2%). The prevalence of vHIT abnormality increased significantly with age, with the highest rate observed in individuals aged >70 years (42.5%). Both hearing and VOR gain deteriorated with age, but the patterns of age-related progression were different. While hearing loss (HL) deteriorated gradually and progressively throughout adulthood, VOR gain deterioration was markedly evident after 70 years of age.

CONCLUSION

Considering the high prevalence of vHIT abnormality, appropriate social and medical policies are needed to prevent associated injuries and improve patients' quality of life. The distinct age-related changes in HL and objective findings of vestibular dysfunction indicate the need for different approaches to address these social problems in aging countries.

Application of a Video Head Impulse Test in the Diagnosis of Vestibular Neuritis

In patients presenting in the emergency department with acute vertigo, a rapid and accurate differential diagnosis is crucial, as posterior circulation strokes can mimic acute vestibular losses, leading to inappropriate treatment. The diagnosis of vestibular neuritis is made based on the clinical manifestation and a bedside otoneurological assessment. In the clinical examination, an evaluation of the vestibulo-ocular reflex is the key element; however, the accuracy of the bedside head impulse test depends on the clinician's experience. Thus, new diagnostic methods are needed to objectify and facilitate such rapid vestibular evaluations. The aim of our paper is to provide a comprehensive review of the video head impulse test's application in the diagnosis of vestibular neuritis. Numerous studies have reported advantages that make this method helpful in detailed otoneurological evaluations; in contrast to the bedside head impulse test, it enables an analysis of all six semicircular canals function and records the covert corrective saccades, which are invisible to the naked eye. As a portable and easy diagnostic tool, it is known to improve the diagnostic accuracy in patients with acute vertigo presenting in the emergency department. Moreover, as it evaluates the vestibulo-ocular reflex across different frequencies, as compared to caloric tests, it can be used as an additional test that is complementary to videonystagmography. Recently, several papers have described the application of the video head impulse test in follow-up and recovery evaluations in patients with vestibular neuritis.

Video head impulse test in stroke: a review of published studies

Accurate and timely diagnosis of posterior circulation stroke in patients with acute dizziness is a challenge that can lead to misdiagnosis and significant harm. The present review sought to identify and describe published research on the clinical application of vHIT in posterior circulation stroke. vHIT, a portable device, has gained prominence in evaluating peripheral vestibular disorders and offers potential applications in diagnosing neurological disorders, particularly posterior circulation stroke. Several studies have shown that vHIT can differentiate between stroke and vestibular neuritis based on VOR gain values, with high sensitivity and specificity. The manuscript also discusses vHIT's performance in differentiating between types of posterior circulation stroke, such as PICA, AICA, and SCA strokes. While vHIT has demonstrated promise, the review emphasizes the need for further research to validate its use as a tool to rule out stroke in acute dizziness patients in the emergency department. In conclusion, the manuscript underscores the potential of vHIT as a valuable addition to the diagnostic arsenal for acute dizziness, particularly in the context of posterior circulation stroke. It calls for further research and wider adoption of vHIT in clinical settings to improve patient care and reduce unnecessary costs associated with misdiagnoses.

Prospective analysis of video head impulse tests in patients with acute posterior circulation stroke

Background

Video head impulse tests (vHITs), assessing the vestibulo-ocular reflex (VOR), may be helpful in the differential diagnosis of acute dizziness. We aimed to investigate vHITs in patients with acute posterior circulation stroke (PCS) to examine whether these findings could exhibit significant abnormalities based on lesion locations, and to evaluate diagnostic value of vHIT in differentiating dizziness between PCS and vestibular neuritis (VN).

Methods

We prospectively recruited consecutive 80 patients with acute PCS and analyzed vHIT findings according to the presence of dorsal brainstem stroke (DBS). We also compared vHIT findings between PCS patients with dizziness and a previously studied VN group (n = 29). Receiver operating characteristic (ROC) analysis was performed to assess the performance of VOR gain and its asymmetry in distinguishing dizziness between PCS and VN.

Results

Patients with PCS underwent vHIT within a median of 2 days from stroke onset. Mean horizontal VOR gain was 0.97, and there was no significant difference between PCS patients with DBS (n = 15) and without (n = 65). None exhibited pathologic overt corrective saccades. When comparing the PCS group with dizziness (n = 40) to the VN group (n = 29), patients with VN demonstrated significantly lower mean VOR gains in the ipsilesional horizontal canals (1.00 vs. 0.57, p < 0.001). VOR gain and their asymmetry effectively differentiated dizziness in the PCS from VN groups, with an area under the ROC curve of 0.86 (95% CI 0.74-0.98) and 0.91 (95% CI 0.83-0.99, p < 0.001), respectively.

Conclusion

Significantly abnormal vHIT results were rare in patients with acute PCS, even in the presence of DBS. Moreover, vHIT effectively differentiated dizziness between PCS and VN, highlighting its potential for aiding differential diagnosis of acute dizziness.

Systematic review and meta-analysis of the diagnostic accuracy of spontaneous nystagmus patterns in acute vestibular syndrome

Objectives

For the assessment of patients presenting with acute prolonged vertigo meeting diagnostic criteria for acute vestibular syndrome (AVS), bedside oculomotor examinations are essential to distinguish peripheral from central causes. Here we assessed patterns of spontaneous nystagmus (SN) observed in AVS and its diagnostic accuracy at the bedside.

Methods

MEDLINE and Embase were searched for studies (1980-2022) reporting on the bedside diagnostic accuracy of SN-patterns in AVS patients. Two independent reviewers determined inclusion. We identified 4,186 unique citations, examined 219 full manuscripts, and analyzed 39 studies. Studies were rated on risk of bias (QUADAS-2). Diagnostic data were extracted and SN beating-direction patterns were correlated with lesion locations and lateralization.

Results

Included studies reported on 1,599 patients, with ischemic strokes (n = 747) and acute unilateral vestibulopathy (n = 743) being most frequent. While a horizontal or horizontal-torsional SN was significantly more often found in peripheral AVS (pAVS) than in central AVS (cAVS) patients (672/709 [94.8%] vs. 294/677 [43.4%], p < 0.001), torsional and/or vertical SN-patterns were more prevalent in cAVS than in pAVS (15.1 vs. 2.6%, p < 0.001). For an (isolated) vertical/vertical-torsional SN or an isolated torsional SN specificity (97.7% [95% CI = 95.1-100.0%]) for a central origin etiology was high, whereas sensitivity (19.1% [10.5-27.7%]) was low. Absence of any horizontal SN was more frequently observed in cAVS than in pAVS (55.2 vs. 7.0%, p < 0.001). Ipsilesional and contralesional beating directions of horizontal SN in cAVS were found at similar frequency (28.0 vs. 21.7%, p = 0.052), whereas for pAVS a contralesional SN was significantly more frequent (95.2 vs. 2.5%, p < 0.001). For PICA strokes presenting with horizontal SN, beating direction was ipsilesional more often than contralesional (23.9 vs. 6.4%, p = 0.006), while the opposite was observed for AICA strokes (2.2 vs. 63.0%, p < 0.001).

Conclusions

(Isolated) vertical and/or torsional SN is found in a minority (15.1%) of cAVS patients only. When present, it is highly predictive for a central cause. A combined torsional-downbeating SN-pattern may be observed in pAVS also in cases with isolated lesions of the inferior branch of the vestibular nerve. Furthermore, in cAVS patients the SN beating direction itself does not allow a prediction on the lesion side.

VOR gain of lateral semicircular canal using video head impulse test in acute unilateral vestibular hypofunction: A systematic review

Introduction

Acute unilateral vestibular hypofunction is characterized by sudden onset of vertigo or dizziness, vomiting/nausea, gait instability, and nystagmus. This is commonly described as an acute vestibular syndrome and usually attributed to vestibular neuritis; however, up to 25% of acute vestibular syndrome is caused by a stroke of posterior circulations. The video head impulse test is a recent tool in the vestibular test battery that assesses the vestibule-ocular reflex by measuring the VOR gain and recording overt and covert saccades, these findings have been found to be helpful in the diagnosis of various vestibular disorders.

Method

A literature search was conducted in databases, including PubMed Central, PubMed, and Web of Science. All the articles that define video head impulse test (vHIT), acute vestibular hypofunction, and vestibular neuritis were considered for the preliminary search. No limits were placed on the date of publication. The searches were limited to studies with full-text availability, published in English, and including human subjects. Search words such as "head impulse test," "video head impulse test," "vestibular ocular reflex," "acute vestibular syndrome," "acute vestibular hypofunction," "vestibular neuritis," and "vHIT in central vestibular disorders" were entered into different databases in different combinations using boolean operators such as AND, OR, and NOT.

Results

Searches across different databases, including Web of Science, PubMed Central, and PubMed, resulted in a total of 1,790 articles. Title screening was done for all the articles. Out of the 1,790 articles, we found that 245 articles were related to vestibular hypofunction i.e., 1,545 articles were removed at this stage. A further 56 duplicate articles were removed. This led to a final screening of 189 articles. The exclusion criteria included unavailability of full text, studies reported in languages other than English, case reports, reviews, and articles including participants having other comorbid conditions. This final screening led to 133 articles being excluded, which led to the full-text screening of 56 articles. After screening the full-text articles as per the eligibility criteria, 21 articles were found to be eligible for the systematic review. Among the remaining studies, six articles were excluded due to different specific reasons. A total of 15 articles were included in this systematic review. The mean VOR gain for the patients with vestibular neuritis was 0.48 ± 0.14 for the ipsilesional ear, whereas the mean VOR gain was > 0.80 in the contralesional ear for all the patients with acute vestibular neuritis. In patients with PICA lesions, the VOR gain for the ipsilesional ear was 0.90 (range 0.87-0.94) and for the contralesional ear was 0.88 (range 0.84-0.93). In patients with AICA lesions, the mean VOR gain was variable. Based on the above mean VOR gain findings, the authors propose the following adjective description scale of VOR of the lateral canal using vHIT: normal VOR gain above 0.80, mild VOR gain loss for 0.70-0.79, moderate loss for 0.69-0.4, severe loss for 0.39-0.2, and profound loss for < 0.2.

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.

Vestibular Autorotation Test: The Differences in Peripheral and Central Acute Vestibular Syndrome

Objective

To evaluate the difference between the vestibular autorotation test (VAT) in the peripheral and central acute vestibular syndrome (AVS). Methodology. Patients with AVS diagnosed by clinical manifestation admitted to the third affiliated hospital of Qiqihar Medical College from January 2019 to January 2021 were enrolled and divided into peripheral AVS (peripheral group) and central AVS (central group) according to the results of the MRI examination.

Results

A total of 332 patients with AVS were recruited, including 282 patients in the peripheral group and 50 patients in the central group. The horizontal gain of both groups showed a downward trend at 2–6 Hz. There was no significant change in the horizontal phase between the two groups at 2–6 Hz. The horizontal gain of the two groups was stable at 2–6 Hz with no significant changes in the horizontal phase between 2–6 Hz in both groups. The central group showed a significantly lower proportion of gain increase coupled with loss and a strikingly higher proportion of gain increase without a loss than in the peripheral group (all P < 0.001).

Conclusion

The increased horizontal and vertical gain of VAT in patients with AVS is of high value in the diagnosis of ACS. Significant differences in the results of VAT in patients with central and peripheral AVS could provide a reference for diagnosis.

Vestibular function testing in the 21st century: video head impulse test, vestibular evoked myogenic potential, video nystagmography; which tests will provide answers?

PURPOSE OF REVIEW

To most neurologists, assessing the patient with vertigo is an unpleasant and worrisome task. A structured history and focused examination can be complemented by carefully selected laboratory tests, to reach an early and accurate diagnosis. We provide evidence-based recommendations for vestibular test selection.

RECENT FINDINGS

The video head impulse test (vHIT), cervical and ocular vestibular evoked myogenic potential (VEMP) and home-video nystagmography are four modern, noninvasive methods of assessing vestibular function, which are equally applicable in the hospital and office-practice. Collectively, they enable assessment of all five vestibular end-organs. The prevalence and patterns of test abnormalities are distinct for each vestibular disorder. We summarize typical abnormalities encountered in four common vestibular syndromes.

SUMMARY

In the context of acute vestibular syndrome, an abnormal vHIT with low gain and large amplitude refixation saccades and an asymmetric oVEMP separates innocuous vestibular neuritis from stroke. In episodic spontaneous vertigo, high-velocity ictal nystagmus and asymmetric cVEMP help separate Ménière's disease from vestibular migraine. In chronic imbalance, all three tests help detect unilateral or bilateral vestibular loss as the root cause. Recurrent positional vertigo requires no laboratory test and can be diagnosed and treated at the bedside, guided by video nystagmography.

Clinical Implication of Corrective Saccades in the Video Head Impulse Test for the Diagnosis of Posterior Inferior Cerebellar Artery Infarction

Objective: In the present study, we characterized the vestibulo-ocular reflex (VOR) gain and properties of corrective saccades (CS) in patients with posterior inferior cerebellar artery (PICA) stroke and determined the best parameter to differentiate PICA stroke from benign peripheral vestibular neuritis (VN). In particular, we studied CS amplitude and asymmetry in video head impulse tests (vHITs) to discriminate these two less-studied disease conditions. Methods: The vHITs were performed within 1 week from symptom onset in patients with PICA stroke (n = 17), patients with VN (n = 17), and healthy subjects (HS, n = 17). Results: PICA stroke patients had bilaterally reduced VOR gains in the horizontal semicircular canal (HC) and the posterior semicircular canal (PC) compared with HSs. When compared with VN patients, PICA stroke patients showed preserved gains in the HC and anterior semicircular canal (AC) bilaterally (i.e., symmetric VOR gain). Similar to VOR gain, smaller but bilaterally symmetric CS in the HC and AC were observed in PICA stroke patients compared with VN patients; the mean amplitude of CS for the ipsilesional HC was reduced (p < 0.001, Mann-Whitney U-test), but the mean amplitude of CS for the contralesional HC was increased (p < 0.03, Mann-Whitney U-test) in PICA stroke compared with VN. The receiver operating characteristic (ROC) curve showed that CS amplitude asymmetry (CSs) and VOR gain asymmetry (Gs) of HC are excellent parameters to distinguish PICA stroke from VN. Conclusion: In the current study, we quantitatively investigated the VOR gain and CS using vHITs for three semicircular canals in PICA stroke and VN patients. In addition to VOR gain, quantitative assessments of CS using vHITs can provide sensitive and objective parameters to distinguish between peripheral and central vestibulopathies.

Vertigo and dizziness in the emergency room

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

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

BACKGROUND AND PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Assessment of the effects of menopause on semicircular canal using the video head impulse test

This cross-sectional study included early menopausal and late menopausal women aged between 40 and 60 years to evaluate the effects of menopause on semicircular canal function. A video head impulse test (vHIT) was performed for all subjects. Vestibulo-ocular reflex (VOR) mean gains of each semicircular canal and gain asymmetry were compared between groups. Of the 87 subjects, 37(42.5%) were reproductive age 28(32.5%) were early menopausal and 22(25.3%) were late menopausal patients. VOR gain of semicircular canals or gain asymmetry values did not differ between groups. In postmenopausal women, presence of vasomotor symptoms was associated with higher gain asymmetry of the left anterior-right posterior (LARP) plane (p = .01), and presence of balance problems was associated with lower right anterior (RA) VOR gain (p = .01). In conclusion semicircular canal function in postmenopausal women was similar to that in women of reproductive age.IMPACT STATEMENTWhat is already known on this subject? During menopause, women face potential risks such as dizziness, balance problems, falls and fractures. Postmenopausal patients were tested with dynamic posturography to measure balance before and after oestrogen treatment, and it was shown that balance problems significantly improved with oestrogen treatment. Healthy vestibular system is one of the components for sustaining normal balance.What do the results of this study add? In postmenopausal women the function of the semicircular canals is normal and the balance deficit in postmenopausal women may not be caused by the vestibular system. In this study changes within normal limits were observed in vestibular system of postmenopausal women.What are the implications of these findings for clinical practice and/or further research? Reported balance deficits might have been due to central origin. Further research to differentiate origin of balance deficits are needed. Specific research on symptomatic postmenopausal patients would reveal more information.

A Case of Isolated Nodular Infarction Mimicking Vestibular Neuritis on the Contralateral Side

Differentiating central vestibulopathy from more common vestibular disorders is crucial because it often necessitates different treatment strategies, and early detection can help to minimize potential complications. Isolated nodular infarct is one of the central brain lesions that can mimic peripheral vertigo. We present a case of isolated nodular infarct that had been misdiagnosed as vestibular neuritis on the contralateral side at the initial evaluation. The patient was successfully treated with anticoagulants and antihyperlipidemic agents. Clinicians should keep in mind that some causes of central vertigo mimic peripheral vestibulopathy at the early stage.

Vascular vertigo: updates

Discriminating strokes in patients with acute dizziness/vertigo is challenging especially when other symptoms and signs of central nervous involvements are not evident. Despite the developments in imaging technology over the decades, a significant proportion of acute strokes may escape detection on imaging especially during the acute phase or when the lesions are small. Thus, small strokes causing isolated dizziness/vertigo would have a higher chance of misdiagnosis in the emergency department. Even though several diagnostic algorithms have been advanced for acute vascular vertigo, we still await more comprehensive and sophisticated ones that can also be applied to transient vestibular symptoms due to vascular compromise. In this respect, vascular and perfusion imaging would be informative. Application of artificial intelligence and tele-consultation may be future perspectives for real-time decision in acute dizziness and vertigo. Several new constellations of ocular motor and vestibular findings have been added to the strokes involving the brainstem and cerebellum. Defining these characteristics would help understanding the function of central vestibular structures and allow more accurate localization of the strokes involving these structures.

Acute vestibular syndrome: clinical head impulse test versus video head impulse test

HINTS battery involving head impulse test (HIT), nystagmus, and test of skew is the critical bedside examination to differentiate acute unilateral peripheral vestibulopathy from posterior circulation stroke (PCS) in acute vestibular syndrome (AVS). The highest sensitivity component of the battery has been reported to be the horizontal HIT, whereas skew deviation is defined as the most specific but non-sensitive sign for PCS. Video-oculography-based HIT (vHIT) may have an additional power in making the differentiation. If vHIT is undertaken, then both gain and gain asymmetry should be taken into account as anterior inferior cerebellar artery (AICA) strokes are at risk of being misclassified based on VOR gain alone. Further refinement in video technology, increased operator proficiency and incorporation with saccade analysis will increase the sensitivity of vHIT for PCS diagnosis. For the time being, clinical examination seems adequate in frontline diagnostic evaluation of AVS.