Hemodynamic orthostatic dizziness/vertigo: Diagnostic criteria

Effect of the early diastolic blood pressure response to the head-up tilt test on the recurrence of benign paroxysmal positional vertigo

BACKGROUND

Otolith organ acts complementarily with the autonomic nervous system to maintain blood pressure. However, the effect of blood pressure variability in the autonomic nervous system on otolith organ has not yet been determined. This study aimed to verify the hypothesis that blood pressure variability in the autonomic nervous system affects the recurrence of benign paroxysmal positional vertigo (BPPV), which is the most common disease of the vestibular organs, by using the head-up tilt test (HUTT).

METHODS

This study included 432 patients diagnosed with idiopathic BPPV. The follow-up period for all patients was 12 months. Age, sex, hypertension, diabetes and recurrence were analyzed. The HUTT parameters were divided into a group of patients whose average diastolic blood pressure increased in the upright position compared to supine position during the HUTT (DBP1) and a group of patients whose average diastolic blood pressure decreased in the upright position compared to supine position during the HUTT (DBP2). Model selection, general loglinear analysis, and logit loglinear analysis were performed using a hierarchically progressing loglinear analysis.

RESULTS

In summary, the group with increased average diastolic blood pressure (DBP1) showed a higher tendency for BPPV recurrence compared to the group with decreased diastolic blood pressure (DBP2) in the upright position during the HUTT, although the difference was not statistically significant (p = 0.080). However, in males, the DBP1 group demonstrated a significantly higher recurrence rate of BPPV than the DBP2 group during the HUTT (95% CI, -20.021 to -16.200; p < 0.001).

CONCLUSIONS

It is presumed that poor autonomic nervous system response through vestibulosympathetic reflex maintains elevated diastolic blood pressure in the upright position during the HUTT. This variability is assumed to affect the recurrence of BPPV.

Age-related differences in the characteristics of persistent postural-perceptual dizziness

Objective

To investigate differences in the clinical characteristics of patients with persistent postural-perceptual dizziness (PPPD) according to age.

Methods

We retrospectively reviewed 143 patients diagnosed with PPPD. Patients were classified into three groups by age: young group (19 to 44 years, n = 60), middle-age group (45 to 64 years, n = 56), old group (65 to 85 years, n = 27). Demographic data, scores of the Dizziness Handicap Inventory (DHI), the Niigata PPPD Questionnaire (NPQ), the Hospital Anxiety and Depression Scale (HADS), precipitating conditions, and the results of vestibular function tests including caloric testing, video head impulse test (vHIT), cervical and ocular vestibular evoked myogenic potentials (cVEMPs and oVEMPs), and posturography, were compared among the three groups.

Results

While there were no significant differences in the scores of the DHI or NPQ, the total score and anxiety score in HADS in the young group were significantly higher than in the old group (p < 0.05, each). On the other hand, for precipitating conditions, the rate of peripheral vestibular diseases was significantly greater in the old group (77.8%) compared to the young group (41.7%, p < 0.01). There was no significant difference in the results of caloric testing, vHIT, cVEMPs, or oVEMPs among the three groups. For posturography, the velocity of the center of pressure with eyes-open as well as with eyes-closed was significantly greater in the old group compared to the young group and the middle-age group (p < 0.005, respectively).

Conclusion

The clinical characteristics of PPPD were different according to age. Young patients tended to have stronger anxiety than old patients whereas the old patients had a higher proportion of peripheral vestibular diseases among the precipitating conditions compared to young patients.

Vertigo During Pregnancy: A Narrative Review of the Etiology, Pathophysiology, and Treatment

From the time of conception until the time of labor, a woman's body and mind undergo a variety of hormonal and other changes. Patients may also experience vertigo and a lack of balance during this period. Disabling and physically painful, these symptoms may strike at any moment. Pregnancy-related vertigo has been the focus of several studies. We looked at the research on vertigo in pregnant women in detail. This narrative review aims to examine the causes, pathophysiology, and current treatments for vertigo during pregnancy. Vertigo during pregnancy has a diverse etiology, with typical causes including hormonal changes and modifications in vascular dynamics. Vertigo may start to appear due to pathophysiological mechanisms involving vestibular and central nervous system adaptations. Numerous alternatives for treatment are available, including dietary changes, vestibular therapy, medicines, and surgical procedures. The thorough assessment of the current research on vertigo during pregnancy provided by this narrative review will help medical practitioners make wise clinical decisions.

Association of self-efficacy, risk attitudes, and time preferences with functioning in older patients with vertigo, dizziness, and balance disorders in a tertiary care setting-Results from the MobilE-TRA2 cohort

Introduction

The functional burden of vertigo, dizziness, and balance problems (VDB) might depend on the personality traits of the patients affected. The aim of this study thus was to investigate the impact of self-efficacy, risk attitudes, and time preferences on functioning in older patients with VDB before and after treatment in a specialized tertiary care center.

Methods

Data for this study was obtained from the MobilE-TRA2 cohort study, conducted at a specialized tertiary care center in Germany. Patients aged 60 and older were assessed during their initial stay at the care center and 3 months later, using self-administered questionnaires. Self-efficacy was measured on a scale from 1 (very low) to 5 (very high). Health-related risk attitudes were inquired using an 11-point scale. Time preferences were measured by evaluating patients' willingness to postpone a reward in favor of a greater benefit on an 11-point Likert scale. Functioning was evaluated using the Dizziness Handicap Inventory, representing functional, emotional, and physical aspects of functional disability caused by VDB. Mixed-effects regression models were used to analyze the association between the selected personality traits and functioning over time. Interaction terms with time were incorporated for each personality trait, enabling the assessment of their influence on functioning 3 months following the initial observation period.

Results

An overall of 337 patients (53% women, median age at baseline = 70 years) were included. Patients with higher self-efficacy (Beta = -3.82, 95%-CI [-6.56; -1.08]) and higher willingness to take risks (Beta = -1.31, 95%-CI [-2.31; -0.31]) reported better functioning during their initial visit at the care center. Self-efficacy significantly predicted functioning after 3 months for overall functioning (Beta = -4.21, 95%-CI [-6.57; -1.84]) and all three domains.

Conclusion

Our findings suggest that patients with high self-efficacy and high willingness to take risks may exhibit better coping mechanisms when faced with the challenges of VDB. Promoting self-efficacy may help patients to better manage the duties accompanying their treatment, leading to improved functioning. These insights may inform the development of personalized treatment aimed at reducing the functional burden of VDB in older patients.

Capturing nystagmus during vertigo attacks using a smartphone: adherence, characteristics, pearls and pitfalls

OBJECTIVE

To investigate adherence, characteristics, and first clinical experiences of capturing ictal nystagmus at home, which can be performed to complement the diagnostic process in patients with episodic vestibular symptoms.

METHODS

Patients were recruited at a tertiary referral center in case capturing ictal nystagmus could contribute to the diagnostic process (e.g., to detect or rule out BPPV). They were asked to capture ictal nystagmus with their own smartphone at home, using a smartphone-based adapter (Nystagmocatcher, Balansdiagnos, Stockholm, Sweden). All recordings were analyzed by the last author (RvdB), and the adherence, characteristics, and first clinical experiences were evaluated.

RESULTS

Seventy patients with vestibular symptoms were asked to participate in this study. Sixty-two (89%) agreed to participate. The median period of participation was 86 days. Fifty-one patients experienced attacks during the study period. Eventually, 51% of them provided eye movement recordings sufficient for analysis. Different types of nystagmus were observed: positional nystagmus related to BPPV, positional nystagmus not related to BPPV, functional eye movements, and the absence of nystagmus or functional eye movements. Capturing ictal nystagmus could contribute to the diagnostic process in several ways, including to detect or rule out BPPV, to detect or rule out vestibular origin of symptoms, to determine the affected side, telemedicine, to monitor attack frequency, and to detect malingering. Furthermore, strict guidance of patients was necessary, which could be time-consuming.

CONCLUSION

Capturing ictal nystagmus can contribute to the diagnostic process in several ways, which motivates to rethink current clinical workflow in vestibular medicine. However, strict guidance is necessary and not all patients provide ictal recordings. In an outpatient setting, it would be advised to use ictal nystagmus recordings on indication, to complement the diagnostic process.

Episodic Vertigo: A Narrative Review Based on a Single-Center Clinical Experience

(1) Background: Usually, the majority of patients suffering from vertigo and dizziness can be identified in four major categories: acute spontaneous vertigo, episodic (recurrent) vertigo, recurrent positional vertigo, and chronic imbalance. Our purpose is to retrospectively evaluate the main causes of episodic vertigo and to find indications for a reliable clinical suspicion useful for a definitive diagnosis, comparing patients affected by different presenting symptomatology (acute vertigo, recurrent episodic vertigo, and imbalance). (2) Methods: we retrospectively evaluated the clinical records in a population of 249 consecutive patients observed for vertigo in our tertiary referral center in the period 1 January 2019-31 January 2020. On the basis of the reported clinical history, patients were divided into three groups: patients with their first ever attack of vertigo, patients with recurrent vertigo and dizziness, and patients with chronic imbalance. (3) Results: On the basis of the results of the instrumental examination, we arbitrarily divided (for each type of symptoms) the patients in a group with a normal vestibular instrumental examination and a group of patients in which the clinical-instrumental evaluation showed some pathological results; a highly significant difference (p: 0.157) was found between recurrent and acute vertigo and between recurrent vertigo and imbalance. (4) Conclusions: Patients with recurrent vertigo more frequently exhibit a negative otoneurological examination since they are often examined in the intercritical phase. A precise and in-depth research of the patient's clinical history is the key to suspect or make a diagnosis together with the search for some instrumental or clinical hallmark, especially in cases where the clinical picture does not fully meet the international diagnostic criteria.

When Particle Repositioning Maneuvers Just Will Not Stick: Clinical Considerations for Persistent Benign Paroxysmal Positional Vertigo

PURPOSE

Although benign paroxysmal positional vertigo (BPPV) is often considered benign and easily treatable, aberrant cases of persistent BPPV can be challenging to manage. Detailed differential diagnosis is essential as central-, vascular-, and cervical-related etiologies may mirror the presentation of persistent BPPV. In addition, an understanding of alternative noninvasive treatment options is important as persistent BPPV is often refractory to traditional particle repositioning maneuvers (PRMs). This article reviews clinical considerations for persistent BPPV.

METHOD

A case of a 68-year-old male diagnosed with posterior semicircular canal BPPV (PC-BPPV) and received various unsuccessful PRMs treatments is described. His clinical presentation is referenced alongside various possible etiologies to discern the most likely diagnosis. Nonsurgical treatment options for intractable PC-BPPV will also be reviewed.

CONCLUSIONS

BPPV recalcitrant to PRM treatment warrants investigation of other etiologies; however, key elements of the case history and objective examination are helpful for differential diagnosis. Brandt-Daroff exercises may facilitate habituation of symptoms secondary to persistent BPPV. More research is needed to understand the use of multiaxial repositioning chairs for the treatment of intractable BPPV.

Volume ratio and distribution rate in patients with orthostatic vertigo/dizziness using MR imaging: a comparison with vertiginous diseases

BACKGROUND

Orthostatic dizziness/vertigo (ODV) is characterized by lightheadedness owing to postural changes.

AIMS/OBJECTIVES

To measure the endolymphatic space (ELS)/total fluid space (TFS) volume ratio and the distribution rate of endolymphatic fluid (ELF) of patients with ODV and compare them with those of control subjects (CS).

MATERIALS AND METHODS

This study included 22 patients (44 ears) with ODV and 52 controls (104 ears, CS). The ELS/TFS volume ratio (%) and distribution rate (%) of the inner ear components were measured using 3-dimensional magnetic resonance imaging.

RESULTS

In the ODV group, the mean ELS/TFS volume ratios of the cochlea, vestibule, and semi-circular canals (SCCs) were 12.1%, 18.6%, and 18.1%, respectively; the mean ELS distribution rates for the cochlea, vestibule, and SCCs were 27.3%, 26.2%, and 46.6%, respectively. The ELS distribution rate of the vestibule was significantly lower (p < .01) and the ELS distribution rate of the SCCs was significantly higher in the ODV than in the CS group (p < .01).

CONCLUSIONS AND SIGNIFICANCE

The ELS distribution rate in the vestibule + SCCs among patients with ODV did not differ from that in the CS; ELF in the vestibule moved to the SCCs, and a large amount of ELF was distributed only in the SCCs.

Symptoms associated with headache in youth

OBJECTIVE

To determine the underlying relationships between a broad range of headache-associated symptoms and how they relate to headache burden.

BACKGROUND

Symptoms associated with head pain inform classification of headache disorders. However, many headache-associated symptoms are not included in the diagnostic criteria, which is largely based on expert opinion. Large symptom databases can assess headache-associated symptoms irrespective of pre-existing diagnostic categories.

METHODS

We conducted a large single-center cross-sectional study on youth (6-17 years old) assessing patient-reported outpatient headache questionnaires between June 2017 and February 2022. Multiple correspondence analysis, an exploratory factor analysis, was applied to 13 headache-associated symptoms.

RESULTS

6662 participants (64% female; median age 13.6 years) were included. Multiple correspondence analysis dimension 1 (25.4% of the variance) captured the absence or abundance of headache-associated symptoms. A greater number of headache-associated symptoms correlated with greater headache burden. Dimension 2 (11.0% of the variance) revealed three symptom clusters: (1) cardinal features of migraine (light, sound, and smell sensitivity, nausea, and vomiting), (2) nonspecific global neurologic dysfunction symptoms (lightheadedness, trouble thinking, blurry vision), (3) vestibular and brainstem dysfunction symptoms (vertigo, balance problems, ear ringing, double vision).

CONCLUSION

Assessing a broader range of headache-associated symptoms reveals clustering of symptomatology and a strong relationship with headache burden.

Functional status associated with postural dizziness, but not postural hypotension, in older adults: a community-based study

BACKGROUND

Functional status, postural dizziness (PD), and postural hypotension (PH) were important issues in older adults. Only one study on the relationship for the three of them in female was without adjusting some important associated factors. This study was intended to investigate the association of PD and PH with functional status in older people of both genders.

METHODS

Based on a stratified randomized cluster sampling, 1361 subjects ≥ 65 years in the community were recruited from Tainan City, Taiwan, from 2000 to 2001. PH was defined as a decrease in systolic/diastolic blood pressure of ≥ 20/10 mm Hg after 1 or 2 min of standing. PD was defined by a positive response to dizziness-like symptoms after standing up from a supine position. Functional status included the activities of daily living (ADLs) and instrumental activities of daily living (IADLs).

RESULTS

After adjusting other variables, ADL disability (OR: 1.84, 95% CI: 1.35-2.51) and IADL disability (OR: 1.62, 95% CI: 1.21-2.17) were associated with PD, but not PH. In male and female subgroups, ADL disability (male OR: 1.70, 95% CI: 1.08-2.67; female OR 1.96, 95% CI: 1.26-3.07) was associated with PD. In male, IADL disability was associated with PD (OR: 2.32, 95% CI: 1.36-3.95).

CONCLUSIONS

Impaired functional status, shown using ADLs or IADLs, was positively associated with PD, but not PH in older adults ≥ 65 years. Clinically, it may be important to evaluate PD in older adults with ADL or IADL disability.

Test-retest of the Subjective Visual Vertical Test performed using a mobile application with the smartphone anchored to a turntable

PURPOSE

The alterations of the Subjective visual vertical test are related to vestibular pathology. Our previously validated method to distinguish between healthy and pathological individuals measures the deviation from the Subjective visual vertical using a mobile application installed on a smartphone fixed to a turntable anchored to the wall. The aim of this study was evaluating the intra-observer reliability of our method in individuals with or without vestibular pathology.

METHODS

Participants were recruited consecutively. In each individual two measurements with an interval of 2 h were made. Both tests were performed by the same examiner. A total of 91 patients were included in this study, of which 25 were healthy and 66 diseased. Intra-observer reliability was evaluated using the intraclass correlation coefficient (ICC). To assess the clinical accuracy of the measurement, we calculated the standard error of the measurement (SEM) and the minimum detectable change (MDC) with a 95% confidence interval.

RESULTS

Intra-observer reliability was excellent with an ICC 0.95 (0.92-0.97) in the whole sample, in healthy patients 0.91 (0.80-0.96) and in pathological patients 0.92 (0.87-0.95). The SEM was calculated to be 0.59 for the whole sample (0.26 in the "healthy" group, and 0.67 in the pathological group). Likewise, the sample's MDC was 1.16, being 0.52 and 1.36 for the healthy and the pathological group, respectively.

CONCLUSIONS

Considering the results, our method presents an excellent intraobserver reliability. Furthermore, changes in deviation greater than 0.52 in healthy individuals and 1.36 in pathological individuals can be considered a real change in deviation.

Acute unilateral vestibulopathy/vestibular neuritis: Diagnostic criteria

This paper describes the diagnostic criteria for Acute Unilateral Vestibulopathy (AUVP), a synonym for vestibular neuritis, as defined by the Committee for the Classification of Vestibular Disorders of the Bárány Society. AUVP manifests as an acute vestibular syndrome due to an acute unilateral loss of peripheral vestibular function without evidence for acute central or acute audiological symptoms or signs. This implies that the diagnosis of AUVP is based on the patient history, bedside examination, and, if necessary, laboratory evaluation. The leading symptom is an acute or rarely subacute onset of spinning or non-spinning vertigo with unsteadiness, nausea/vomiting and/or oscillopsia. A leading clinical sign is a spontaneous peripheral vestibular nystagmus, which is direction-fixed and enhanced by removal of visual fixation with a trajectory appropriate to the semicircular canal afferents involved (generally horizontal-torsional). The diagnostic criteria were classified by the committee for four categories: 1. "Acute Unilateral Vestibulopathy", 2. "Acute Unilateral Vestibulopathy in Evolution", 3. "Probable Acute Unilateral Vestibulopathy" and 4. "History of Acute Unilateral Vestibulopathy". The specific diagnostic criteria for these are as follows:"Acute Unilateral Vestibulopathy": A) Acute or subacute onset of sustained spinning or non-spinning vertigo (i.e., an acute vestibular syndrome) of moderate to severe intensity with symptoms lasting for at least 24 hours. B) Spontaneous peripheral vestibular nystagmus with a trajectory appropriate to the semicircular canal afferents involved, generally horizontal-torsional, direction-fixed, and enhanced by removal of visual fixation. C) Unambiguous evidence of reduced VOR function on the side opposite the direction of the fast phase of the spontaneous nystagmus. D) No evidence for acute central neurological, otological or audiological symptoms. E) No acute central neurological signs, namely no central ocular motor or central vestibular signs, in particular no pronounced skew deviation, no gaze-evoked nystagmus, and no acute audiologic or otological signs. F) Not better accounted for by another disease or disorder."Acute Unilateral Vestibulopathy in Evolution": A) Acute or subacute onset of sustained spinning or non-spinning vertigo with continuous symptoms for more than 3 hours, but not yet lasting for at least 24 h hours, when patient is seen; B) - F) as above. This category is useful for diagnostic reasons to differentiate from acute central vestibular syndromes, to initiate specific treatments, and for research to include patients in clinical studies."Probable Acute Unilateral Vestibulopathy": Identical to AUVP except that the unilateral VOR deficit is not clearly observed or documented."History of acute unilateral vestibulopathy": A) History of acute or subacute onset of vertigo lasting at least 24 hours and slowly decreasing in intensity. B) No history of simultaneous acute audiological or central neurological symptoms. C) Unambiguous evidence of unilaterally reduced VOR function. D) No history of simultaneous acute central neurological signs, namely no central ocular motor or central vestibular signs and no acute audiological or otological signs. E) Not better accounted for by another disease or disorder. This category allows a diagnosis in patients presenting with a unilateral peripheral vestibular deficit and a history of an acute vestibular syndrome who are examined well after the acute phase.It is important to note that there is no definite test for AUVP. Therefore, its diagnosis requires the exclusion of central lesions as well as a variety of other peripheral vestibular disorders. Finally, this consensus paper will discuss other aspects of AUVP such as etiology, pathophysiology and laboratory examinations if they are directly relevant to the classification criteria.

Relationship between orthostatic hypotension and recurrence of benign paroxysmal positional vertigo

Blood pressure is maintained by a combined mechanism of the baroreceptor reflex and the vestibulosympathetic reflex. This study is intended to verify the hypothesis that the orthostatic hypotension (OH) seen when benign paroxysmal positional vertigo (BPPV) occurred may act as a factor that affects the recurrence of BPPV. The subjects of present study were selected from among 239 patients diagnosed with idiopathic BPPV. The average age of the group with OH was 59.3 years, and the age of the group without OH was 50.3 years, with a statistically significant difference (P = 0.013). It was shown that drug-taking increased the risk of OH occurrence by 4.08 times (C.I for exp(B): 1.20-13.77) compared to the group that did not take drugs. It was shown that the risk of recurrence of BPPV was significantly reduced in the no recurrence group compared to the multiple recurrence group when there was no OH (p = 0.000; aOR 0.0000002). Also, the risk of recurrence was significantly reduced in the no recurrence group compared to the multiple recurrence group when there was no drug-taking (p = 0.000 aOR 0.0000001). This study is the first study that studied the effect of OH on the recurrence of BPPV and showed the possibility that OH could partially influence the recurrence of BPPV.

Females with Diabetes Mellitus Increased the Incidence of Premenstrual Syndrome

Background: Premenstrual syndrome (PMS) is a multifactorial disorder caused by hormone and autonomic imbalance. In our study, hyperglycemia-induced insulin secretion increased progesterone secretion and progressive autonomic imbalance. The young patients with diabetes mellitus (DM) revealed hypo-parasympathetic function and hypersympathetic function compared with nondiabetic controls. Young female patients with DM with higher blood sugar and autonomic malfunction may be associated with PMS. However, there is a lack of evidence about DM in females related to PMS. We evaluated female patients with DM who subsequently followed PMS in a retrospective cohort study. Methods: We retrieved data from the National Health Insurance Research Database in Taiwan. Female patients with DM between 20 and 50 years old were assessed by the International Classification of Disease, 9 Revision, Clinical Modification (ICD-9-CM) disease code of 250. Patients who were DM-free females were fourfold matched to the control group by age and disease index date. The ICD-9-CM disease code of 625.4 identified the incidence of PMS followed by the index date as events. The possible risk factors associated with PMS were detected with a Cox proportional regression. Results: DM was a significant risk factor for PMS incidence with an adjusted hazard ratio of 1.683 (95% confidence interval: 1.104−2.124, p < 0.001) in females after adjusting for age, other comorbidities, season, urbanization status of patients and the hospital status of visiting. Conclusions: This study noted an association between DM and PMS in female patients. Healthcare providers and female patients with DM must be aware of possible complications of PMS, aggressive glycemic control, decreased hyperglycemia and autonomic dysfunction to prevent this bothersome disorder.

Presence of exacerbating factors of persistent perceptual-postural dizziness in patients with vestibular symptoms at initial presentation

Objective

To investigate the presence of exacerbating factors of persistent perceptual-postural dizziness (PPPD) in patients with vestibular symptoms during the early period after vestibular symptoms onset, and to examine possible predictive factors for developing PPPD later.

Methods

One hundred and fifty-five consecutive patients with vestibular symptoms who presented less than 90 days from the onset were included in this study. They filled out the Niigata PPPD Questionnaire (NPQ) that consists of 12 questions on the exacerbating factors of PPPD. The NPQ scores of patients who developed PPPD were compared with those of patients who did not develop PPPD during the follow-up.

Results

Seventy-eight of the155 patients (50.3%) showed positive NPQ scores (≥27 points). High NPQ scores were found in patients diagnosed with psychogenic dizziness and vestibular neuritis. During the follow up for an average of 543.3 days after the initial presentation, eight patients (10.3%) developed PPPD. Seven of these eight patients (87.6%) showed positive NPQ scores and all of them had all three exacerbating factors of PPPD at their initial presentation. The NPQ scores of the patients who developed PPPD (40.6 ± 11.6) were significantly higher than those of the patients who did not develop PPPD (26.4 ± 18.3; p <.05).

Conclusion

Approximately a half of the patients with vestibular symptoms had exacerbating factors of PPPD in the early stages of the disease. Patients who develop PPPD are likely to have its exacerbating factors in the initial stages after presentation. Level of Evidence: 3.

“Sitting-up vertigo as an expression of posterior semicircular canal heavy cupula and posterior semicircular canal short arm canalolithiasis”

Background

Vestibular symptoms on sitting-up are frequent on patients seen by vestibular specialists. Recently, a benign paroxysmal positional vertigo (BPPV) variant which elicits vestibular symptoms with oculomotor evidence of posterior semicircular canal (P-SCC) cupula stimulation on sitting-up was described and named sitting-up vertigo BPPV. A periampullar restricted P-SCC canalolithiasis was proposed as a causal mechanism.

Objective

To describe new mechanisms of action for the sitting-up vertigo BPPV variant.

Methods

Eighteen patients with sitting-up vertigo BPPV were examined with a pre-established set of positional maneuvers and follow-up until they resolved their symptoms and clinical findings.

Results

All patients showed up-beating torsional nystagmus (UBTN) and vestibular symptoms on coming up from either Dix-Hallpike (DHM) or straight head-hanging maneuver. Sixteen out of 18 patients presented a sustained UBTN with an ipsitorsional component to the tested side on half-Hallpike maneuver (HH). A slower persistent contratorsional down-beating nystagmus was found in eleven out 18 patients tested on nose down position (ND).

Conclusions

Persistent direction changing positional nystagmus on HH and ND positions indicative of P-SCC heavy cupula was found in 11 patients. A sustained UBTN on HH with the absence of findings on ND, which is suggestive of the presence of P-SCC short arm canalolithiasis, was found on 5 patients. All patients were treated with canalith repositioning maneuvers without success, but they resolved their findings by means of Brandt-Daroff exercises. We propose P-SCC heavy cupula and P-SCC short arm canalolithiasis as two new putative mechanisms for the sitting-up vertigo BPPV variant.

Vestibular-autonomic interactions: beyond orthostatic dizziness

PURPOSE OF REVIEW

This review aims to summarize the current literature describing vestibular-autonomic interactions and to describe their putative role in various disorders' clinical presentations, including orthostatic dizziness and motion sensitivity.

RECENT FINDINGS

The vestibular-autonomic reflexes have long been described as they relate to cardiovascular and respiratory function. Although orthostatic dizziness may be in part related to impaired vestibulo-sympathetic reflex (orthostatic hypotension), there are various conditions that may present similarly. A recent clinical classification aims to improve identification of individuals with hemodynamic orthostatic dizziness so that appropriate recommendations and management can be efficiently addressed. Researchers continue to improve understanding of the underlying vestibular-autonomic reflexes with recent studies noting the insular cortex as a cortical site for vestibular sensation and autonomic integration and modulation. Work has further expanded our understanding of the clinical presentation of abnormal vestibular-autonomic interactions that may occur in various conditions, such as aging, peripheral vestibular hypofunction, traumatic brain injury, and motion sensitivity.

SUMMARY

The vestibular-autonomic reflexes affect various sympathetic and parasympathetic functions. Understanding these relationships will provide improved identification of underlying etiology and drive improved patient management.

Orthostatic hemodynamics in the vertebral artery and blood pressure in patients with orthostatic dizziness/vertigo

OBJECTIVES

Orthostatic dizziness/vertigo (ODV) is a common symptom and is believed to occur due to the cerebral hypoperfusion caused by orthostatic hypotension (OH). However, the detailed mechanism underlying ODV onset is poorly understood. The vertebral artery (VA) mainly supplies blood to the central vestibular system; therefore, the orthostatic decrease of VA blood flow could possibly lead to ODV. This study investigated the orthostatic blood pressure and VA hemodynamics in ODV patients to elucidate the hemodynamic mechanism underlying ODV onset. Furthermore, the influence of orthostatic hypotension (OH) on VA hemodynamics was examined because OH is probably the most common cause of ODV.

METHODS

This study included 181 patients with ODV and 73 control patients without ODV. All subjects underwent an active standing test to measure the extracranial Doppler (ECD) sonography spectrum of the VA and blood pressure (BP). VA blood flow velocity and BP were simultaneously measured for each patient in the supine static position and then in the upright standing positions following 3 min of standing. We investigated the orthostatic change in the average of flow velocity in bilateral VAs (VAFV) and BP for ODV patients compared with the control patients.

RESULT

VAFV in ODV patients was significantly reduced when standing up compared with the control patients. In the ODV patients, there was no difference in orthostatic decrease in VAFV between patients those with OH and without OH. However, the VAFV in the standing position was significantly lower in patients with OH than without OH. In cases with OH, the ODV patients exhibited a greater decrease in VAFV compared with the control patients, but this was not statistically significant. In the absence of OH, a significantly greater orthostatic decrease in VAFV was observed in ODV patients compared with the controls.

CONCLUSION

Our findings suggest that the orthostatic decrease of VA blood flow is deeply involved in the hemodynamic mechanism underlying ODV onset and is possibly associated with OH and other etiologies.

Reduction in Pulse Pressure during Standing Can Distinguish Neurogenic Orthostatic Hypotension

Background: We investigated whether changes in the pulse pressure (PP) reduction ratio during the head-up tilt test (HUTT) can aid in distinguishing neurogenic orthostatic hypotension (OH) from non-neurogenic OH. Methods: We enrolled consecutive patients with NOH and non-neurogenic OH between January 2015 and October 2018. We compared the Valsalva ratio, the presence or absence of late phase II and IV overshoot, the pressure recovery time, and the PP reduction ratio during HUTT between the two OH groups. Results: The expiratory–inspiratory (E:I) ratio and Valsalva ratio were significantly decreased in the NOH group (p = 0.026, p < 0.001, respectively). The absence of late phase II and phase IV overshoot was more frequent in the NOH group than in the non-neurogenic OH group (p = 0.001, p < 0.001, respectively). The pressure recovery time was significantly prolonged in the NOH group (p < 0.001), which exhibited increases in the PP reduction ratio (1—minimal PP/baseline PP) during the HUTT (p < 0.001). We calculated the cutoff point for the PP reduction ratio during HUTT, which exhibited an area under the receiver operating characteristic curve of 0.766 (0.659–0.840, 95% confidence interval). The cutoff value for the PP reduction ratio during HUTT (0.571) exhibited sensitivity of 0.879 and specificity of 0.516. Conclusions: Increases in the PP reduction ratio during HUTT may be a meaningful NOH laboratory marker.

New Frontiers in Managing the Dizzy Patient

Despite progress in vestibular research in the last 20 years, much remains poorly understood about vestibular pathophysiology and its management. A shared language is a critical first step in understanding vestibular disorders and is under development. Telehealth will continue for patients with dizziness, and ambulatory monitoring of nystagmus will become a diagnostic tool. In the next 2 decades, it is anticipated that vestibular perceptual threshold testing will become common in tertiary centers, imaging with improved spatial resolution will yield better understanding of vestibular pathophysiology, and that vestibular implants will become a part of clinical practice.

Current Insights into Treating Vertigo in Older Adults

The number of older people has been increasing over recent decades in Western populations. Dizziness, imbalance, and vertigo constitute some of the most common complaints in older patients, and risk of falling is the most frequent and worrying consequence. It has been reported that 15–20% of the adult population experiences these debilitating symptoms. Among the diseases that may be associated with vertigo, the three classes of otological, central, and functional (psychological) dizziness may be distinguished. Overall, vestibular disorders account for 48% of vertiginous complaints in the older population. The main focus of this article is to review the forms of pharmacotherapy for vertigo, especially with regard to older patients, who may be treated simultaneously with other drugs for different comorbidities. Interactions with other drugs should be considered in the choice of a particular course of treatment. Moreover, overuse of pharmacotherapy for the management of vertigo in the elderly may prevent the development of the central compensatory mechanism that sustains both static and dynamic imbalance after a vertiginous crisis. In the majority of patients, vestibular and physical rehabilitation are strongly advised and rarely contraindicated.

Efficacy of the subjective visual vertical test performed using a mobile application to detect vestibular pathology

BACKGROUND

The subjective visual vertical (SVV) test is a sensitive test of vestibular dysfunction that allows the evaluation of otolithic organs; however, with the current method, there are technical and logistical limitations that make the application of this test difficult in the conventional clinic.

OBJECTIVE

The objective of this study is to assess the effectiveness of detecting vestibular pathology using the SVV via a new screening method.

METHODS

A consecutive sample of 62 patients with suspected vestibular pathology was included in the study. The patients were clinically diagnosed according to the Barany Society criteria. An exploratory system was designed using a mobile application in Android that detects accelerometer oscillations and involves placing the smartphone on a rotating disk anchored to the wall. All patients underwent a SVV examination using the bucket method and the study test. A cut-off point of the ROC curve was calculated for each test, and its sensitivity, specificity, diagnostic accuracy and probability ratios for detecting vestibular pathology were analysed. The SVV results were compared using the bucket test and the study test.

RESULTS

We observed significant differences in sensitivity between the two tests: 86.95% for the study test versus 67.4% for the bucket test (p <  0.01). In the ROC curve, an area under the curve of 0.90 was observed for the study test, with a cut-off of 2.43 for a sensitivity of 86.95% and a specificity of 93.75%.

CONCLUSIONS

SVV testing using a smartphone placed on a rotating disk anchored to the wall offers greater diagnostic accuracy than SVV using the bucket test. Both methods are inexpensive, harmless and easily accepted by patients.

Recurrent Vestibular Symptoms Not Otherwise Specified: Clinical Characteristics Compared With Vestibular Migraine and Menière's Disease

Despite the huge progress in the definition and classification of vestibular disorders within the last decade, there are still patients whose recurrent vestibular symptoms cannot be attributed to any of the recognized episodic vestibular syndromes, such as Menière's disease (MD), vestibular migraine (VM), benign paroxysmal positional vertigo (BPPV), vestibular paroxysmia, orthostatic vertigo or transient ischemic attack (TIA). The aim of the present international, multi-center, cross-sectional study was to systematically characterize the clinical picture of recurrent vestibular symptoms not otherwise specified (RVS-NOS) and to compare it to MD and VM. Thirty-five patients with RVS-NOS, 150 patients with VM or probable VM and 119 patients with MD were included in the study. The symptoms of RVS-NOS had been present for 5.4 years on average before inclusion, similar to VM and MD in this study, suggesting that RVS-NOS is not a transitory state before converting into another diagnosis. Overall, the profile of RVS-NOS vestibular symptoms was more similar to VM than MD. In particular, the spectrum of vestibular symptom types was larger in VM and RVS-NOS than in MD, both at group comparison and the individual level. However, in contrast to VM, no female preponderance was observed for RVS-NOS. Positional, head-motion and orthostatic vertigo were reported more frequently by patients with RVS-NOS than MD, while external vertigo was more prevalent in the MD group. At group level, the spectrum of attack durations from minutes to 3 days was evenly distributed for VM, while a small peak for short and long attacks in RVS-NOS and a big single peak of hours in MD were discernible. In general, vertigo attacks and associated vegetative symptoms (nausea and vomiting) were milder in RVS-NOS than in the other two disorders. Some patients with RVS-NOS described accompanying auditory symptoms (tinnitus: 2.9%, aural fullness and hearing loss: 5.7% each), migrainous symptoms (photophobia, phonophobia or visual aura in 5.7% each) or non-migrainous headaches (14%), but did not fulfill the diagnostic criteria for MD or VM. Absence of a life time diagnosis of migraine headache and attack duration of <5 min were further reasons not to qualify for VM. In some RVS-NOS patients with accompanying ear symptoms, attack durations of <20 min excluded them from being diagnosed with MD. These findings suggest that RVS-NOS is a stable diagnosis over time whose overall clinical presentation is more similar to VM than to MD. It is more likely to be composed of several disorders including a spectrum of mild or incomplete variants of known vestibular disorders, such as VM and MD, rather than a single disease entity with distinct pathognomonic features.

Vertigo in Patients with Degenerative Cervical Myelopathy

(1) Background: Cervical vertigo (CV) represents a controversial entity, with a prevalence ranging from reported high frequency to negation of CV existence. (2) Objectives: To assess the prevalence and cause of vertigo in patients with a manifest form of severe cervical spondylosis-degenerative cervical myelopathy (DCM) with special focus on CV. (3) Methods: The study included 38 DCM patients. The presence and character of vertigo were explored with a dedicated questionnaire. The cervical torsion test was used to verify the role of neck proprioceptors, and ultrasound examinations of vertebral arteries to assess the role of arteriosclerotic stenotic changes as hypothetical mechanisms of CV. All patients with vertigo underwent a detailed diagnostic work-up to investigate the cause of vertigo. (4) Results: Symptoms of vertigo were described by 18 patients (47%). Causes of vertigo included: orthostatic dizziness in eight (22%), hypertension in five (14%), benign paroxysmal positional vertigo in four (11%) and psychogenic dizziness in one patient (3%). No patient responded positively to the cervical torsion test or showed significant stenosis of vertebral arteries. (5) Conclusions: Despite the high prevalence of vertigo in patients with DCM, the aetiology in all cases could be attributed to causes outside cervical spine and related nerve structures, thus confirming the assumption that CV is over-diagnosed.

Perspectives: Evaluation of Older Adult Cochlear Implant Candidates for Fall Risk in a Developing Country Setting

Dizziness, vertigo, and falls are common in older adults. Data suggest that cochlear implant candidates are no different and could be argued to be at elevated risk due to the presence of hearing loss and likely vestibular involvement. Perspectives contextualizes current testing and screening paradigms for vestibular deficits and fall risk and suggests a protocol suitable for use in developing country settings.

A Set of Eight Key Questions Helps to Classify Common Vestibular Disorders-Results From the DizzyReg Patient Registry

Precise history taking is the key to develop a first assumption on the diagnosis of vestibular disorders. Particularly in the primary care setting, algorithms are needed, which are based on a small number of questions and variables only to guide appropriate diagnostic decisions. The aim of this study is to identify a set of such key variables that can be used for preliminary classification of the most common vestibular disorders. A four-step approach was implemented to achieve this aim: (1) we conducted an online expert survey to collect variables that are meaningful for medical history taking, (2) we used qualitative content analysis to structure these variables, (3) we identified matching variables of the patient registry of the German Center for Vertigo and Balance Disorders, and (4) we used classification trees to build a classification model based on these identified variables and to analyze if and how these variables contribute to the classification of common vestibular disorders. We included a total of 1,066 patients with seven common vestibular disorders (mean age of 51.1 years, SD = 15.3, 56% female). Functional dizziness was the most frequent diagnosis (32.5%), followed by vestibular migraine (20.2%) and Menière's disease (13.3%). Using classification trees, we identified eight key variables which can differentiate the seven vestibular disorders with an accuracy of almost 50%. The key questions comprised attack duration, rotational vertigo, hearing problems, turning in bed as a trigger, doing sport or heavy household chores as a trigger, age, having problems with walking in the dark, and vomiting. The presented algorithm showed a high-face validity and can be helpful for taking initial medical history in patients with vertigo and dizziness. Further research is required to evaluate if the identified algorithm can be applied in the primary care setting and to evaluate its external validity.

Increased Incidence of Premenstrual Syndrome in Females with Palmar Hyperhidrosis

Background: Premenstrual syndrome (PMS) is a common disorder affecting the quality of life of women of reproductive age. In a previous study, sex hormone imbalances and alterations in autonomic function were present in PMS, with parasympathetic dysfunction and sympathetic overactivity during the late luteal phase. Palmar hyperhidrosis (PH) presents with oversweating, heat and emotional stimulation, sympathetic hyperactivity and parasympathetic hypofunction. We hypothesized that the incidence of PMS is increased in females with PH. Methods: Data were retrieved from the Taiwanese National Health Insurance Database. The patients with PH were identified by the International Classification of Disease, 9th Revision, Clinical Modification (ICD-9-CM) disease code 780.8. Female patients matched by age and index day were used as the control group. The incidence of PMS was considered an outcome by the ICD-9-CM disease code 625.4. The factors related to PMS were analyzed by Cox regression. Results: The adjusted hazard ratio for the incidence of PMS was 1.276 (95% confidence interval: 1.05–1.488) in females with PH. Conclusions: This study found a positive correlation between PMS and female PH patients. Patients and physicians must understand the relationship of PMS with autonomic function alterations and other risk factors to prevent this problematic disorder.

Vestibular Migraine of Childhood and Recurrent Vertigo of Childhood: Diagnostic criteria Consensus document of the Committee for the Classification of Vestibular Disorders of the Bárány Society and the International Headache Society

This paper describes the diagnostic criteria for “Vestibular Migraine of Childhood”, “probable Vestibular Migraine of Childhood” and “Recurrent Vertigo of Childhood” as put forth by the Committee for the Classification of Vestibular Disorders of the Bárány Society (ICVD) and the Migraine Classification subgroup of the International Headache Society. Migraine plays an important role in some subgroups of children with recurrent vertigo. In this classification paper a spectrum of three disorders is described in which the migraine component varies from definite to possibly absent. These three disorders are: Vestibular Migraine of Childhood, probable Vestibular Migraine of Childhood and Recurrent Vertigo of Childhood. The criteria for Vestibular Migraine of Childhood (VMC) include (A) at least five episodes with vestibular symptoms of moderate or severe intensity, lasting between five minutes and 72 hours, (B) a current or past history of migraine with or without aura, and (C) at least half of episodes are associated with at least one migraine feature. Probable Vestibular Migraine of Childhood (probable VMC) is considered when at least three episodes with vestibular symptoms of moderate or severe intensity, lasting between five minutes and 72 hours, are accompanied by at least criterion B or C from the VMC criteria. Recurrent Vertigo of Childhood (RVC) is diagnosed in case of at least three episodes with vestibular symptoms of moderate or severe intensity, lasting between 1 minute and 72 hours, and none of the criteria B and C for VMC are applicable. For all disorders, the age of the individual needs to be below 18 years old. It is recommended that future research should particularly focus on RVC, in order to investigate and identify possible subtypes and its links or its absence thereof with migraine.

Clinician Use and Payments by Medical Specialty for Audiometric and Vestibular Testing Among US Medicare Beneficiaries

Importance

Variations in diagnostic test use may indicate that there are opportunities for quality improvement in vestibular health care. To date, the extent to which clinician acquisition of tests varies nationwide by region and specialty of the clinician is unknown.

Objective

To quantify variation in clinician use and payments for audiograms and vestibular tests across all geographic regions of the United States and by specialty of practice.

Design, Setting, and Participants

This cross-sectional study used a population-based sample of 1 307 887 audiovestibular test claims from fee-for-service Medicare beneficiaries aged 65 years or older in the Medicare Provider Utilization and Payment Public Use File from January 1 through December 31, 2014. The analysis was completed from January 2 through June 1, 2019.

Exposures

Diagnostic audiograms, caloric testing, and rotary chair testing.

Main Outcomes and Measures

Test utilization was analyzed by hospital referral region, medical specialty, and total payments.

Results

In 2014, clinicians performed 1 213 328 audiograms, 317 880 caloric tests (ie, single caloric irrigations), and 62 779 rotary chair tests, for a total of $38 647 350.21 in Medicare payments from the Centers for Medicare & Medicaid Services. No patient or clinician demographic characteristics were available. Across health care referral regions, rates of testing per 100 000 beneficiaries varied from 166 to 12 021 for audiograms, 15 to 4271 for caloric tests, and 13 to 3556 for rotary chair tests between the lowest-use and highest-use regions. Most audiograms and caloric tests were billed by audiologists (797 957 audiograms [65.8%]; 112 485 caloric tests [35.4%]) and otolaryngologists (376 728 audiograms [31.0%]; 70 567 caloric tests [22.2%]). In contrast, primary care physicians (18 933 [30.2%]) and neurologists (15 254 [24.3%]) billed the largest proportion of rotary chair tests compared with other specialists, including audiologists (7253 [11.6%]) and otolaryngologists (6464 [10.3%]).

Conclusions and Relevance

Substantial geographic and clinician-level variation may have been observed in use of audiovestibular tests. Quality improvement efforts in vestibular health care may need to target a range of clinicians, including primary care physicians to be successful.

Cardiogenic vertigo: characteristics and proposed diagnostic criteria

Early identification of cardiogenic vertigo (CV) is necessary to prevent serious complications of cardiovascular diseases. However, the literature is limited to case reports without detailed clinical features or diagnostic criteria. The aim of this study was to define characteristics of CV and propose diagnostic criteria. This study included patients with CV diagnosed at Pusan National University and Keimyung University Hospitals. Demographic, clinical, laboratory, and treatment data were analyzed. Of 72 patients with clinically suspicious CV, 27 were finally included. The age ranged from 63 to 88 years (75.1 ± 7.2 years). Recurrent vertigo occurred without syncopal attacks in 52% [95% CI, 32-71], while it preceded (37% [19-58]) or followed (11% [2-29]) syncope. The patients with recurrent isolated vertigo had suffered from symptoms from 15 days to 5 years until final diagnosis (median 122 days). The vertigo lasted only for a few seconds (93% [76-99]) or a few minutes (7% [1-24]). Fourteen patients presented with spinning vertigo, and one of them showed spontaneous downbeat nystagmus during the attack. Accompanying symptoms including chest discomfort, palpitation, headache, arm twitching, and lightheadedness were found in 70% [50-86]. Between patients with and without syncope, there was no difference in clinical parameters and results of cardiac function tests. The most common cardiac abnormality during the attacks of vertigo was bradyarrhythmia (89% [71-98]). Cardiovascular diseases can develop recurrent isolated vertigo without or preceding syncope. Onset age, duration of vertigo, accompanying symptoms, and underlying cardiac diseases can aid in differentiation from other vestibular disorders. Early identification of CV would reduce morbidity and mortality associated with cardiac syncope.

A new simple method using carotid duplex ultrasonography to assess intracranial vertebrobasilar arterial stenosis

OBJECTIVES

Magnetic resonance angiography (MRA), three-dimensional computed tomography angiography, and cerebral angiography may be used to assess intracranial vertebrobasilar stenosis. However, these examinations cannot be performed at patients' bedsides. Our purpose was to develop a new bedside method to assess intracranial vertebrobasilar arterial stenosis.

METHODS

We developed the new method using carotid duplex ultrasonography combined with the head-up test. A total of 141 subjects admitted between June 1, 2017 and March 31, 2019 were enrolled in this study. We calculated vertebral arterial peak systolic velocities (PSVs), end-diastolic velocities (EDVs), and mean velocities (MVs) at 0°, 16°, and 30° head-up angles. Vertebrobasilar arterial stenosis was confirmed using MRA.

RESULTS

We excluded 28 subjects and included data for 113 subjects and 226 vessels in the final analysis. Cervical vertebral arterial PSV, EDV, and MV gradually decreased from 0° to 30° only in stenotic intracranial vertebral arteries. Sensitivity (probability of detection) was 75.5% and specificity (true negative rate) was 79.7% when EDV at the 30° head-up angle decreased ≥19.5% from the initial 0° head-up angle. Specificity was better (86.4%; sensitivity: 69.4%) when EDV was <9.1 cm/s at the 30° head-up angle.

CONCLUSION

This new method easily detects intracranial vertebrobasilar arterial stenosis.

[Effective diagnostics for vertigo, dizziness and equilibrium disorders]

Vertigo, dizziness and equilibrium disorders are symptoms with a variety of causes. First, four cardinal questions (type and duration of the vertigo, triggering factors, accompanying symptoms) must be answered. After that, the search for a spontaneous nystagmus (differentiation of peripheral and central disorder using the HINTS[head impulse, nystagmus, test of skew]-test ) and, as part of a positioning examination, the search for a benign paroxysmal positional vertigo (BPPV) are necessary. If the result is negative an instrument-based receptor-specific examination is carried out. The caloric examination (low-frequency stimulus) tests the horizontal semicircular canal and the superior vestibular nerve, whereas the 3‑D video head impulse test (vHIT, high-frequency stimulus) is used to analyze all three semicircular canals as well as the superior and inferior vestibular nerves. Analysis of the cervical vestibular evoked myogenic potential (cVEMP) checks the function of the sacculus and that of the ocular VEMP (oVEMP) checks the function of the utriculus. The final overall analysis usually gives a definitive diagnosis or at least provides a suspected diagnosis, which then determines the further diagnostic procedure (e.g. targeted radiological diagnostics if vestibular paroxysmia, superior canal dehiscence or a vestibular schwannoma are suspected).

Etiologic distribution of dizziness and vertigo in a referral-based dizziness clinic in South Korea

This study aimed to determine the etiologic distribution of dizziness and vertigo in a referral-based dizziness clinic in South Korea. We analyzed the diagnoses of 21,166 consecutive dizzy patients (12,691 women, mean age = 57.9 ± 15.7, age range = 3-97) seen from 2003 to 2019 using a registry and medical records. Overall, dizziness and vertigo were more common in women (60.0%, CI 0.59-0.61) than in men without a difference in age (57.7 ± 15.5 vs. 58.1 ± 16.1, p = 0.094). Benign paroxysmal positional vertigo (BPPV, 24.1%) was the most common cause of dizziness/vertigo, followed by psychiatric or persistent postural perceptual dizziness (20.8%), vascular disorders (12.9%), vestibular migraine (10.2%), Meniere's disease (7.2%), and vestibular neuritis (5.4%). These six disorders comprised more than 80% of all disorders. The etiology could not be determined in 5.0%, and more than one etiology was found in 14.1%. Vestibular migraine was the most common disorder in children and adolescents (< 19 years), psychiatric or persistent postural perceptual dizziness (26.3%) in the adults (19-64 years), and BPPV (28.2%) in the elderly (≥ 65 years). This etiologic distribution is similar to that reported in another country, and indicates no significant differences in the proportion of diseases causing dizziness and vertigo across different ethnic groups. This study provides valuable information to establish healthcare policy for dizziness and vertigo.

[The Bárány Classification of vestibular disorders, its clinical implementation and future prospects]

Vestibular diseases often have no or only nonspecific biomarkers. It is therefore necessary to define these disorders using operational criteria based on patterns of symptoms, i.e., the presence of inclusion and exclusion criteria, similar to the situation with headaches or psychiatric diseases. Ten years ago, the Bárány Society embarked upon development of the International Classification of Vestibular Disorders (ICVD). This entails producing the different definitions iteratively according to a structured procedure with an internal review process, resulting in an open-access publication on the diagnostic criteria in each case. It is a multidisciplinary effort, and depending on the topic, cooperation with other scientific societies is sought. The classification encompasses primary vestibular disorders and non-vestibular disorders that may manifest with prominent vestibular symptoms. The following paper describes the procedure and briefly presents definitions which have already been published as well as those presently in elaboration.

Spatial Navigation Is Distinctively Impaired in Persistent Postural Perceptual Dizziness

Objective: To determine whether performance in a virtual spatial navigational task is poorer in persistent postural perceptual dizziness (PPPD) patients than in healthy volunteers and patients suffering other vestibular disorders.

Methods: Subjects were asked to perform three virtual Morris water maze spatial navigational tasks: (i) with a visible target, (ii) then with an invisible target and a fixed starting position, and finally (iii) with an invisible target and random initial position. Data were analyzed using the cumulative search error (CSE) index.

Results: While all subjects performed equally well with a visible target, the patients with PPPD (n = 19) performed poorer (p < 0.004) in the invisible target/navigationally demanding tasks (CSE median of 8) than did the healthy controls (n = 18; CSE: 3) and vestibular controls (n = 19; CSE: 4). Navigational performance in the most challenging setting allowed us to discriminate PPPD patients from controls with an area under the receiver operating characteristic curve of 0.83 (sensitivity 78.1%; specificity 83.3%). PPPD patients manifested more chaotic and disorganized search strategies, with more dispersion in the navigational pool than those of the non-PPPD groups (standard distance deviation of 0.97 vs. 0.46 in vestibular controls and 0.20 in healthy controls; p < 0.001).

Conclusions: While all patients suffering a vestibular disorder had poorer navigational abilities than healthy controls did, patients with PPPD showed the worst performance, to the point that this variable allowed the discrimination of PPPD from non-PPPD patients. This distinct impairment in spatial navigation abilities offers new insights into PPPD pathophysiology and may also represent a new biomarker for diagnosing this entity.