Cupulolithiasis

Subjective visual vertical deviation in patients with early-onset direction-changing horizontal positional nystagmus

OBJECTIVE

Otolithic dysfunction is investigated in cases of direction-changing horizontal positional nystagmus (DCHPN) due to peripheral vestibular disorders.

METHODS

The static-subjective visual vertical (S-SVV) was conducted in DCHPN cases within 48 h after onset.

RESULTS

The absolute values of S-SVV deviations of patients with Light cupula and lateral canal-benign paroxysmal positional vertigo-cupulolithiasis (L-BPPV-Cup) were significantly different from those of healthy subjects (p < 0.001, p < 0.05, respectively), whereas there were no significant differences in those of patients with L-BPPV-Canalolithiasis-geotropic (L-BPPV-Can-g) or L-BPPV-Can-ageotropic (L-BPPV-Can-a) versus healthy subjects. Significant differences were found in S-SVV (+: deviation to the affected side, -: deviation to the unaffected side) between patients with Light cupula and those with L-BPPV-Can-g, L-BPPV-Can-a and L-BPPV-Cup (p < 0.01, p < 0.05, and p < 0.001, respectively), as well as between those with L-BPPV-Can-g and L-BPPV-Cup (p < 0.01). The S-SVV in patients with Light cupula, L-BPPV-Can-g, and L-BPPV-Can-a deviated more to the affected side, whereas that in patients with L-BPPV-Cup deviated more to the unaffected side.

CONCLUSION

Mild otolithic dysfunctions were found in patients with DCHPN due to the presence of peripheral vestibular disorders within 48 h after onset. The extent of otolithic (utricular) disorders in patients with DCHPN is estimated in decreasing order as follows: Light cupula > L-BPPV-Cup > L-BPPV-Can-g and L-BPPV-Can-a. Many patients with L-BPPV-Cup likely suffer from disorders of the pars externa of the utricular macula, whereas many patients with L-BPPV-Can-g likely suffer from disorders of the pars interna of the utricular macula. L-BPPV-Can-a and L-BPPV-Can-g must be induced by a common mild utricular disorder.

Examining Migraine as a Predictor of Benign Paroxysmal Positional Vertigo Onset, Severity, Recurrence, and Associated Falls

Introduction: The comorbidity of migraine and benign paroxysmal positional vertigo (BPPV) is well-established, yet the impact of migraine on the BPPV phenotype remains understudied.

Methods: A retrospective analysis of patients at a tertiary dizziness/vertigo clinic diagnosed with BPPV from 2015 and 2020 was conducted. The study's primary outcomes were the age of BPPV onset, Dizziness Handicap Index (DHI), BPPV recurrence, and dizziness-related falls.

Results: In our cohort of 255 BPPV patients, 44.7% had a history of migraine. Those with migraine had an earlier age of BPPV onset than individuals without migraine (60.2 vs. 65.4, p = 0.0018). Migraineurs and non-migraineurs did not differ in their DHI (44.7 vs. 41.6, p= 0.44), recurrence rates (48.3% vs. 40.4%, p= 0.21), and falls (32.5% vs. 37.6%, p = 0.39). Among individuals with horizontal canal BPPV, a higher proportion of migraineurs experienced falls than non-migraineurs (50.0% vs. 6.3%, p = 0.02).

Conclusions: Migraineurs experience BPPV at a younger age than those without migraine. This finding suggests that migraine, which has been shown to cause inner ear damage, predisposes individuals to developing BPPV earlier. Migraine was also associated with a higher rate of falls among patients with horizontal canal BPPV, indicating that a migraine history may impact the phenotype of BPPV.

Clinical Application of Different Vertical Position Tests for Posterior Canal-Benign Paroxysmal Positional Vertigo-Cupulolithiasis

Background

Posterior canal-benign paroxysmal positional vertigo-cupulolithiasis (PC-BPPV-cu) is a new and controversial type of benign paroxysmal positional vertigo (BPPV). At present, there are few relevant clinical studies as to whether the Half Dix-Hallpike test (Half D-HT) induces more obvious nystagmus than the Dix Hallpike test (D-HT) and straight head hanging test (SHH) in patients with PC-BPPV-cu.

Objectives

To investigate the clinical characteristics of PC-BPPV-cu, and analyze the diagnostic significance of the Dix-Hallpike test (D-HT), Half D-HT, and straight head hanging (SHH) test in these patients.

Methods

A total of 46 patients with PC-BPPV-cu were enrolled, and divided into two groups (N = 23): a group A (induction order: D-HT, Half D-HT, SHH) and a group B (induction order: Half D-HT, D-HT, SHH).

Results

Among 46 patients with PC-BPPV-cu, the bilateral and unilateral abnormality rates of the disease side were 5 cases and 41 cases, respectively. There were significant differences in the proportion of torsional-upbeating nystagmus and upbeating nystagmus among the three headhanging positions in 46 patients with PC-BPPV-cu (P &lt; 0.001). The slow phase velocity (SPV) of induced nystagmus at half D-HT supine position was slower than D-HT supine position (P &lt; 0.05) and SHH supine position (P &lt; 0.05). The nystagmus latency of D-HT supine position was significantly shorter than half D-HT (P &lt; 0.05) and SHH (P &lt; 0.05). PC-BPPV-cu patients were accompanied by 53.5% semicircular canal paresis, 69.6% audiological abnormalities, 76% cervical vestibular evoked myogenic potential (cVEMP), and 75% video head impulse test (vHIT) abnormalities, the concordance rates of the four detection methods were similar (χ2 = 0.243, P = 0.970).

Conclusions

The Half D-HT is simple and feasible, but might have a risk of false-negative diagnoses of the torsional-upbeating nystagmus and upbeating nystagmus. The D-HT is still a classic induction method for PC-BPPV-cu. The two complement each other and may aid in the diagnosis of PC-BPPV-cu patients. Future clinical applications of Half D-HT require extensive research to determine its diagnostic efficacy.

Predictors of residual dizziness in patients with benign paroxysmal positional vertigo after successful repositioning: A multi-center prospective cohort study

BACKGROUND

While patients with benign paroxysmal positional vertigo (BPPV) commonly develop residual dizziness (RD) after successful repositioning, the factors predictive of RD remain controversial.

OBJECTIVE

To identify factors predictive of RD onset in patients with BPPV following successful repositioning.

METHODS

This multi-center prospective cohort study enrolled 243 patients with idiopathic BPPV. Vestibular functional and psychological wellbeing assessments administered before repositioning provided the data used to identify factors predictive of RD with a log-binomial model. The endpoint was RD at 1 week after successful repositioning.

RESULTS

Of the enrolled patients, 118 reported RD. After adjusting for cofounders, mild [risk ratio (RR), 2.06; 95% confidence interval (CI), 1.39-3.04] or severe (RR, 3.08; 95% CI, 2.17-4.38) anxiety and abnormal vestibular ratio of sensory organization test (RR, 2.68; 95% CI, 1.82-3.95) were identified as risk predictors. Presence of ocular vestibular evoked myogenic potentials responses, either unilateral (RR, 0.55; 95% CI, 0.44-0.69) or bilateral (RR, 0.49; 95% CI, 0.36-0.68), were protective factors.

CONCLUSIONS

Anxiety and abnormal balance are significant predictors of RD, while the presence of ocular vestibular evoked myogenic potentials responses predicts against it. These findings may help to improve BPPV outcomes by informing prognoses and guiding treatment strategies.

TRIAL REGISTRATION

ChiCTR1800018004 (date of registration: 26 August 2018).

Analysis of related factors of recurrence in horizontal semicircular canal benign paroxysmal positional vertigo: a pilot study

Background: Whether the abnormal caloric test (C-test) affects recurrence rate in horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV) with residual dizziness (RD) is not clear.Objectives: 1) Analyze the association of the cycles of canalith repositioning procedure (CRP), C-test and RD after CRP and 2) determine which affects the recurrence rate in idiopathic HSC-BPPV.Materials and methods: Eighty-four patients with HSC-BPPV (canal type) were included in this work. The cycles of CRP, C-test, the RD after CRP and HSC-BPPV recurrence rate were recorded. Depending on the times of CRP and patients who presented dizziness after treatment, patients were divided into four groups, the relationship between abnormal C-test and RD was analyzed. The outcomes of recurrence rate were compared between groups, respectively.Results: (1) The abnormal C-test prevalence among the HSC-BPPV patients with RD was 36% while in no RD group was 14.7%. The difference was statistically significant (p = .045). (2) The recurrence rate was 11.8% in no RD group but in RD group the rate was higher (32%, p = .039). When patients combined with abnormal C-test, the recurrence rate was significantly higher (77.8% vs. 20%) (p = .033).Conclusions: A weak correlation between RD and abnormal C-test is noted. Presence of RD and abnormal C-test in patients with HSC-BPPV predicts a higher recurrence rate.

Effects of vestibular rehabilitation, with or without betahistine, on managing residual dizziness after successful repositioning manoeuvres in patients with benign paroxysmal positional vertigo: a protocol for a randomised controlled trial

INTRODUCTION

Benign paroxysmal positional vertigo (BPPV) is recognised as the leading cause of peripheral vertigo in adults. The canalith repositioning procedure (CRP) can be used for effective treatment of BPPV. However, some patients experience residual dizziness (RD) even after successful CRP, resulting in a significant negative impact on their daily function and quality of life. Exercise-based vestibular rehabilitation (VR) has been proven as an effective method for managing dizziness and has been applied in patients with various vestibular disorders. However, the efficacy of VR to specifically target RD post-BPPV is unknown. This study aims to investigate the efficacy of VR, compared with betahistine or VR plus betahistine treatment, in the treatment of patients experiencing RD after successful CRP.

METHODS AND ANALYSIS

A randomised single-blinded controlled trial will be carried out to determine the efficacy of VR compared with betahistine or VR plus betahistine treatment in mitigating RD and improving balance function. Patients with BPPV who experience RD after successful CRP will be recruited. Participants will be randomised into one of three groups to receive VR, betahistine or VR plus betahistine. There will be 61 participants in each group. The primary outcomes will be changes in the patient's daily function as measured by the Vestibular Activities and Participation questionnaire and balance ability assessed by computerised dynamic posturography. The secondary outcomes will be dizziness-related handicap, otolith function and duration of RD symptoms. Outcome measures will be noted at baseline and at 2, 4 and 8 weeks post-randomisation. This study has the potential to reduce unnecessary anti-vertigo drug prescriptions and may lead to a general consensus regarding the use of VR as a first-line treatment for RD in patients with BPPV.

ETHICS AND DISSEMINATION

This trial received ethical approval from the Institutional Review Board of Eye and ENT Hospital of Fudan University (reference number 2017046). The study results will be disseminated via peer-reviewed journals and conferences.

TRIAL REGISTRATION NUMBER

NCT03624283; Pre-results.

Dizziness handicap and clinical characteristics of posterior and lateral canal BPPV

PURPOSE

Benign paroxysmal positional vertigo (BPPV) is diagnosed and divided into subtypes based on positioning vertigo and nystagmus. Whether these subtypes entail any significant differences in patient-reported symptoms; is yet not known. Such differences may have clinical and therapeutic consequences. Our aim was to assess dizziness handicap and clinical characteristics of posterior and lateral canal BPPV.

METHODS

This prospective observational multicentre study analysed consecutive patients with BPPV, confirmed by standardized procedures including videonystagmography under diagnostic manoeuvres in a biaxial rotational chair. Patients were screened for other neurological and otological disorders.

OUTCOMES

Dizziness handicap inventory (DHI), posterior vs. lateral canal involvement.

FACTORS

age, gender, positional nystagmus intensity (maximum slow-phase velocity), symptom duration, 25-hydroxyvitamin D-level and traumatic aetiology.

RESULTS

132 patients aged 27-90 (mean 57, SD 13) years were included. Higher DHI scores were associated with lateral canal BPPV [95% CI (1.59-13.95), p = 0.01] and female gender [95% CI (0.74-15.52), p = 0.03]. Lateral canal BPPV was associated with longer symptom duration [OR 1.10, CI (1.03-1.17), p = 0.01] and lower 25-hydroxyvitamin D-levels [OR 0.80, CI (0.67-0.95), p = 0.03]. There was no correlation between DHI scores and nystagmus intensity.

CONCLUSIONS

This study suggests that patients with lateral canal BPPV have increased patient-perceived disability, lower vitamin D-levels and longer duration of symptoms. This subtype might therefore require closer follow-up. Patient-perceived disability is not related to positional nystagmus intensity.

Diagnosis strategy and Yacovino maneuver for anterior canal-benign paroxysmal positional vertigo

OBJECTIVE

To investigate the diagnosis strategy of anterior canal-benign paroxysmal positional vertigo (AC-BPPV) and the therapeutic effects of the Yacovino maneuver.

METHODS

The clinical data of 40 AC-BPPV patients were collected. The nystagmus characteristics induced by the Dix-Hallpike (D-H) and straight head-hanging (SHH) tests, the diagnostic methods used, and the effectiveness of the Yacovino maneuver for the treatment of AC-BPPV were all retrospectively analyzed.

RESULTS

Among the 40 cases analyzed, 19 patients had simple AC-BPPV, 11 patients had AC-posterior canal BPPV, and 10 patients had AC-horizontal canal BPPV. D-H and SHH tests showed down-beating nystagmus in 26 and 33 patients, respectively, and showed down-beating and torsional nystagmus in 14 and 7 patients, respectively. AC-BPPV was diagnosed in 15 patients based on the presence of typical BPPV in other canals, in 9 patients based on typical disease history and the results of position tests, in 6 patients based on effectiveness of the treatment with the Yacovino maneuver, in 4 patients based on the treatment effectiveness and the presence of typical BPPV in other canals, in 3 patients based on the treatment effectiveness and the follow-up outcome, in 2 patients based on the typical BPPV in other canals and occurrence of canal conversion, and in 1 patient based on the treatment effectiveness and occurrence of canal conversion. Thirteen patients with canalolithiasis and four patients with cupulolithiasis were cured after the initial Yacovino maneuver treatment. Twenty-one patients with canalolithiasis and seven patients with cupulolithiasis were cured following 1 week of treatment.

CONCLUSIONS

The effectiveness of the Yacovino maneuver, the follow-up outcome, the presence of typical BPPV in other canals, and the occurrence of canal conversions contribute to AC-BPPV diagnosis. The Yacovino maneuver was found to be more effective in AC-BPPV patients with canalolithiasis than in those with cupulolithiasis.

Semicircular canal biomechanics in health and disease

The semicircular canals are responsible for sensing angular head motion in three-dimensional space and for providing neural inputs to the central nervous system (CNS) essential for agile mobility, stable vision, and autonomic control of the cardiovascular and other gravity-sensitive systems. Sensation relies on fluid mechanics within the labyrinth to selectively convert angular head acceleration into sensory hair bundle displacements in each of three inner ear sensory organs. Canal afferent neurons encode the direction and time course of head movements over a broad range of movement frequencies and amplitudes. Disorders altering canal mechanics result in pathological inputs to the CNS, often leading to debilitating symptoms. Vestibular disorders and conditions with mechanical substrates include benign paroxysmal positional nystagmus, direction-changing positional nystagmus, alcohol positional nystagmus, caloric nystagmus, Tullio phenomena, and others. Here, the mechanics of angular motion transduction and how it contributes to neural encoding by the semicircular canals is reviewed in both health and disease.

Proposal on the Diagnostic Criteria of Definite Isolated Otolith Dysfunction

BACKGROUND AND OBJECTIVES

Dizzy patients with abnormal otolith function tests, despite a normal caloric response, are defined as having specific (isolated) otolith organ dysfunction. This study was performed to compare the differences in clinical presentation between isolated otolith dysfunction (iOD) patients with lab- and Sx-based iOD group and lab-based iOD symptoms.

SUBJECT AND METHODS

The medical records of 23 iOD patients with normal caloric response but abnormal cervical vestibular evoked myogenic potential (VEMP), ocular VEMP, or subjective visual vertical were reviewed. Non-spinning vertigo was considered as otolith-related symptoms. The patients' age, onset of dizziness, Numeric Rating Scale on the severity of dizziness, and concomitant vestibular disorders were analyzed.

RESULTS

Patients in the lab-based iOD group were significantly older than those in the lab- and Sx-based iOD group. Known vestibular disorders were significantly more common in the lab-based iOD group (83.3%) compared to the lab- and Sx-based iOD group (18.2%). Despite the normal caloric response, catch-up saccade was found in the video head impulse test in more than half (54.5%) of the lab-based iOD group patients. There was no catch-up saccade in the lab- and Sx-based iOD group. There were no significant differences in gender ratio, frequency of dizziness attacks, and duration of illness.

CONCLUSIONS

We propose new definitions of definite iOD (lab- and Sx-based iOD) and probable iOD (lab- or Sx-based iOD). These new definitions may help researchers to identify patients who are more likely to have true iOD, and facilitate comparisons of results between different studies.

Surgical Treatment for Recurrent Benign Paroxysmal Positional Vertigo

Introduction Benign paroxysmal positional vertigo is a generally benign condition that responds to repositioning maneuvers and frequently resolves spontaneously. However, for some patients it can become a disabling condition in which surgery must be considered. Two different surgical techniques exist, singular neurectomy and posterior semicircular canal occlusion. Objective The objective of this study is to review the current status of singular nerve section and posterior semicircular canal occlusion as treatments for intractable benign paroxysmal positional vertigo, and to determine if there are published data available that favors one over the other. Data Sources MEDLINE and OLDMEDLINE databases of the National Library of Medicine. Data Synthesis Four studies regarding singular neurectomy and 14 reports on semicircular canal occlusion were analyzed. Both techniques are reported to provide similar symptomatic benefit, with low risk of hearing loss and balance impairment. However, anatomical and clinical studies of singular neurectomy show it to be a more challenging technique, and considering that it is indicated in a very small number of cases, it may be difficult to master. Conclusions Both singular neurectomy and semicircular canal occlusion can be safe and effective in those few patients that require surgery for intractable positional vertigo. Although semicircular canal occlusion requires a postauricular transmastoid approach, it is ultimately easier to learn and perform adequately, and thus may be considered the best alternative.

Otoconia and otolithic membrane fragments within the posterior semicircular canal in benign paroxysmal positional vertigo

OBJECTIVES/HYPOTHESIS

Benign paroxysmal positional vertigo (BPPV) is the most common vestibular disorder with an incidence between 10.7 and 17.3 per 100,000 persons per year. The mechanism for BPPV has been postulated to involve displaced otoconia resulting in canalithiasis. Although particulate matter has been observed in the endolymph of affected patients undergoing posterior canal occlusion surgery, an otoconial origin for the disease is still questioned.

STUDY DESIGN

In this study, particulate matter was extracted from the posterior semicircular canal of two patients and examined with scanning electron microscopy.

METHODS

The samples were obtained from two patients intraoperatively during posterior semicircular canal occlusion. The particles were fixed, stored in ethanol, and chemically dehydrated. The samples were sputter coated and viewed under a scanning electron microscope. Digital images were obtained.

RESULTS

Intact and degenerating otoconia with and without linking filaments were found attached to amorphous particulate matter. Many otoconia appeared to be partially embedded in a gel matrix, presumably that which encases and anchors the otoconia within the otolith membrane, whereas others stood alone with no attached filaments and matrix. The otoconia measured roughly 2 to 8 μm in length and displayed a uniform outer shape with a cylindrical bulbous body and a 3 + 3 rhombohedral plane at each end.

CONCLUSIONS

These findings suggest that the source of the particulate matter in the semicircular canals of patients with BPPV is broken off fragments of the utricular otolithic membrane with attached and detached otoconia.

LEVEL OF EVIDENCE

NA Laryngoscope, 127:709-714, 2017.

Sudden sensorineural hearing loss with positional vertigo: Initial findings of positional nystagmus and hearing outcomes

OBJECTIVES

To investigate the initial findings of positional nystagmus in patients with sudden sensorineural hearing loss (SSNHL) and positional vertigo, and to compare hearing improvement among patients with different types of positional nystagmus.

DESIGN

The characteristics of positional nystagmus upon initial examination were analysed, and the initial mean pure-tone audiometry (PTA) threshold was compared with that at three months after treatment.

STUDY SAMPLE

Forty-four SSNHL patients with concomitant positional vertigo were included.

RESULTS

Positional nystagmus was classified into five subgroups; persistent geotropic direction-changing positional nystagmus (DCPN) in head-roll test (HRT) and negative Dix-Hallpike test (DHT), persistent apogeotropic DCPN in HRT and negative DHT, positive DHT and negative HRT, persistent geotropic DCPN in HRT and positive DHT, and persistent apogeotropic DCPN in HRT and positive DHT. PTA threshold improvement was significantly greater in SSNHL patients with negative DHT than with positive DHT (p = 0.027).

CONCLUSIONS

When geotropic DCPN was elicited by HRT, the nystagmus was persistent, which suggests that alteration of specific gravity of the endolymph, rather than the lateral canal canalolithiasis, may be a cause of this characteristic positional nystagmus. Positive DTH may be a prognostic factor for worse hearing recovery among patients with SSNHL and positional vertigo.

Principles of calcite dissolution in human and artificial otoconia

Human otoconia provide mechanical stimuli to deflect hair cells of the vestibular sensory epithelium for purposes of detecting linear acceleration and head tilts. During lifetime, the volume and number of otoconia are gradually reduced. In a process of degeneration morphological changes occur. Structural changes in human otoconia are assumed to cause vertigo and balance disorders such as benign paroxysmal positional vertigo (BPPV). The aim of this study was to investigate the main principles of morphological changes in human otoconia in dissolution experiments by exposure to hydrochloric acid, EDTA, demineralized water and completely purified water respectively. For comparison reasons artificial (biomimetic) otoconia (calcite gelatin nanocomposits) and natural calcite were used. Morphological changes were detected in time steps by the use of environmental scanning electron microscopy (ESEM). Under in vitro conditions three main dissolution mechanisms were identified as causing characteristic morphological changes of the specimen under consideration: pH drops in the acidic range, complex formation with calcium ions and changes of ion concentrations in the vicinity of otoconia. Shifts in pH cause a more uniform reduction of otoconia size (isotropic dissolution) whereas complexation reactions and changes of the ionic concentrations within the surrounding medium bring about preferred attacks at specific areas (anisotropic dissolution) of human and artificial otoconia. Owing to successive reduction of material, all the dissolution mechanisms finally produce fragments and remnants of otoconia. It can be assumed that the organic component of otoconia is not significantly attacked under the given conditions. Artificial otoconia serve as a suitable model system mimicking chemical attacks on biogenic specimens. The underlying principles of calcite dissolution under in vitro conditions may play a role in otoconia degeneration processes such as BPPV.

Benign Paroxysmal Positional Vertigo: An Integrated Perspective

Benign paroxysmal positional vertigo (BPPV), the most common cause of dizziness, occurs in all age groups. It presents with vertigo on head movement, but in older patients presentation may be typical and thus accounting for a low recognition rate in the primary care setting. It may be recurrent in up to 50% of cases. BPPV is associated with displacement of fragments of utricular otoconia into the semicircular canals, most commonly the posterior semicircular canal. Otoconia are composed of otoconin and otolin forming the organic matrix on which calcium carbonate mineralizes. Otoconia may fragment with trauma, age, or changes in the physiology of endolymph (e.g., pH and calcium concentration). Presentation varied because otoconia fragments can be displaced into any of the semicircular canals on either (or both) side and may be free floating (canalolithiasis) or attached to the cupula (cupulolithiasis). Most cases of BPPV are idiopathic, but head trauma, otologic disorders, and systemic disease appear to be contributory in a subset. Positional maneuvers are used to diagnose and treat the majority of cases. In rare intractable cases surgical management may be considered. A strong association with osteoporosis suggests that idiopathic BPPV may have diagnostic and management implications beyond that of a purely otologic condition.

Enlarged vestibular aqueduct may precipitate benign paroxysmal positional vertigo in children

CONCLUSIONS

Enlarged vestibular aqueduct (EVA) may precipitate secondary benign paroxysmal positional vertigo (BPPV), especially in pediatric populations, as well as paretic dysfunction of the vestibular end organ.

OBJECTIVES

EVA is characterized by the early onset of sudden or progressive sensorineural hearing loss with or without vestibular dysfunction. However, vestibular dysfunction in patients with EVA has not been described as frequently as hearing loss, and an association with BPPV has not been previously reported. By reviewing the cochleo-vestibular status of three children and two young adults with EVA who had been diagnosed with BPPV, characteristic features of BPPV in EVA patients were investigated and possible pathogenetic mechanisms are speculated.

METHODS

A retrospective review of medical records was conducted for five patients with EVA who presented with BPPV from January 2004 to July 2009. Clinical courses, characteristics of vertigo and audiovestibular laboratory findings were reviewed.

RESULTS

Among 26 patients with radiologically confirmed EVA, 5 (19.2%) exhibited positional nystagmus compatible with BPPV through Dix-Hallpike and head-roll tests. Hearing loss usually accompanied BPPV attacks, and BPPV was recurrent in three patients. Multiple semicircular canals were frequently involved in each episode, and different canals were also involved in recurrent cases. Canalith repositioning procedures were usually successful without difficulty.

Benign Paroxysmal Positional Vertigo (BPPV): History, Pathophysiology, Office Treatment and Future Directions

BPPV is the most common cause of vertigo. It most often occurs spontaneously in the 50 to 70 year age group. In younger individuals it is the commonest cause of vertigo following head injury. There is a wide spectrum of severity from inconsistent positional vertigo to continuous vertigo provoked by any head movement. It is likely to be a cause of falls and other morbidity in the elderly. Misdiagnosis can result in unnecessary tests. The cardinal features and a diagnostic test were clarified in 1952 by Dix and Hallpike. Subsequently, it has been established that the symptoms are attributable to detached otoconia in any of the semicircular canals. BPPV symptoms can resolve spontaneously but can last for days, weeks, months, and years. Unusual patterns of nystagmus and nonrepsonse to treatment may suggest central pathology. Diagnostic strategies and the simplest "office" treatment techniques are described. Future directions for research are discussed.

Nystagmus parameters and subtypes of benign paroxysmal positional vertigo

CONCLUSION

Although computational models suggest the existence of canalithiasis and cupulolithiasis subtypes of benign paroxysmal positional vertigo (BPPV), these subtypes cannot be distinguished from each other based on characteristics of nystagmus. Therefore, although the subtypes probably exist more information is needed from each patient than is available without invasive procedures. Also, some patients may have clinical syndromes that include both canalithiasis and cupulolithiasis subtypes.

OBJECTIVE

To determine if the parameters of nystagmus provide sufficient information to determine the subtype of nystagmus in a patient with BPPV.

METHODS

Patients (n = 118) had unilateral BPPV of the posterior canal; 15 patients also had BPPV of the lateral canal. The main outcome measures were parameters of nystagmus in response to the Dix-Hallpike maneuver: latency to onset of nystagmus, maximum slow phase velocity, and maximum duration.

RESULTS

Correlations between pairs of variables showed minimal or no relationships. Also, cluster analyses showed no significant subtypes. The contralateral eye moved significantly faster than the ipsilateral eye.

Revisiting benign paroxysmal positional vertigo pathophysiology

Benign paroxysmal positional vertigo is the most common peripheral cause of vertigo. Although its pathophysiologic mechanisms remain unclear, different locations have been attributed throughout the last century, from the days of Bárány. Disease was initially located by Dix and Hallpike in the utricle, but later, Schuknecht's works elicited the cupulolithiasis and canalolithiasis theories, localizing the pathology to the semicircular canal system and mainly to the posterior one. However, conflicting evidences from temporal bone studies accumulated against this theory, which suggest other explanations. Although this clinical entity is well defined, and can usually be effectively treated with certain physical maneuvers, its pathophysiology is still obscure and is being critically discussed in this article, which reviews the milestones of benign paroxysmal positional vertigo understanding.

Manobra de Epley na vertigem posicional paroxística benigna associada à doença de Ménière

Os efeitos da manobra de Epley na vertigem posicional paroxística benigna (VPPB) associada à doença de Ménière são controvertidos. OBJETIVO: Avaliar a vertigem e o nistagmo de posicionamento após uma ou mais manobras de Epley na vertigem posicional paroxística benigna (VPPB) associada à doença de Ménière e na recorrência da VPPB. MATERISL E MÉTODO: Estudo retrospectivo de 62 pacientes com VPPB associada à doença de Ménière submetidos à manobra de Epley e acompanhados durante 12 meses após a extinção do nistagmo de posicionamento. RESULTADOS: Para abolir o nistagmo de posicionamento, foi necessária uma manobra de Epley em 80,7% dos pacientes, duas em 16,1% e três em 3,2%. A vertigem foi eliminada em 71,0% dos pacientes, melhorou em 27,4% e permaneceu inalterada em 1,6%. Quatro semanas após a extinção do nistagmo de posicionamento, todos os pacientes ficaram assintomáticos. Recorrência da VPPB foi observada em 19,4% dos casos, com eliminação da vertigem e nistagmo de posicionamento à manobra específica para o canal afetado. CONCLUSÕES: Na VPPB associada à doença de Ménière, vertigem e nistagmo de posicionamento foram eliminados com uma, duas ou três manobras de Epley. A recorrência da VPPB foi resolvida com uma manobra para o canal envolvido.

Quantas manobras são necessárias para abolir o nistagmo na vertigem posicional paroxística benigna?

OBJETIVO: Avaliar o número de manobras necessárias para abolir o nistagmo posicional em pacientes com Vertigem Posicional Paroxística Benigna e verificar possíveis influências do substrato fisiopatológico e/ou canal semicircular acometido. FORMA DE ESTUDO: clínico prospectivo com coorte transversal. MATERIAL E MÉTODO: Sessenta pacientes com Vertigem Posicional Paroxística Benigna foram tratados por meio das manobras de reposicionamento de estatocônios, repetidas semanalmente até a abolição do nistagmo. A Análise de Variância foi aplicada para verificar diferenças entre as variáveis dos fatores "substrato fisiopatológico" e "canal semicircular acometido". RESULTADOS: Foram necessárias de 1 a 8 manobras, em média 2,13 para abolir o nistagmo posicional. A cupulolitíase necessitou de um número maior de manobras que a ductolitíase (p=0,0002*) e não houve diferença entre os canais semicirculares (p=0,5213). Nos canais anterior e posterior, a ductolitíase precisou em média de uma a duas manobras e a cupulolitíase precisou em média de três manobras. No canal lateral, tanto a ductolitíase quanto a cupulolitíase precisaram de duas manobras, em média. CONCLUSÕES: São necessárias de uma a oito manobras semanais de reposicionamento de estatocônios, em média duas, para eliminar o nistagmo posicional na Vertigem Posicional Paroxística Benigna. A cupulolitíase necessita de maior número de manobras que a ductolitíase. O canal semicircular acometido não influencia o número de manobras terapêuticas.

Postural stability in patients with different durations of benign paroxysmal positional vertigo

Postural stability maintenance was investigated in patients with "idiopathic" benign paroxysmal positional vertigo of the posterior semicircular canal (BPPV-PSC) and compared to healthy subjects. To measure the postural stability during a quiet upright stance, we used static posturography in two conditions: with open and with closed eyes. The effect of the repositioning Epley's maneuver on the recovery of postural stability in patients with different durations of BPPV-PSC less than 60 days after the first attack of positioning vertigo (group I) and more than 60 days (group II) was examined. The investigation was made 1 h after the positive Dix-Hallpike test and 7 days after treatment with the Epley maneuver. "Sway velocity" (SV) and "relative power spectrum" (RPS) of the stabilograms were calculated to evaluate the postural stability for each subject and each experimental condition. We found a pronounced spectral density peak in the frequency range of 1.0-2.0 Hz and smaller spectral density in the range of 0.15-0.5 Hz compared to that in healthy subjects. Our results showed that the postural maintenance in BPPV-PSC patients depended on the disease duration. Patients with a duration of BPPV symptoms less than 60 days after the first attack demonstrated a high dependence on the visual input for postural stability. One week after the Epley maneuver, differences in the recovery of postural control in both groups of patients were also found. We assume that the disturbed otolith function together with the impaired dynamics of the semicircular canal generate a particular pattern of postural maintenance. The different degree of restoration of postural stability 1 week after the EM treatment in BPPV-PSC patients with different durations of the disease gives us reason to believe that after removing the otoconia from the semicircular canal, some stimulation of other sensory subsystems and adaptation mechanisms occur that lead to a new pattern of postural maintenance.

The number of procedures required to eliminate positioning nystagmus in benign paroxysmal positional vertigo

Aim

To evaluate the number of weekly canalith repositioning procedures needed to eliminate positioning nystagmus in patients with benign paroxysmal positional vertigo and to verify influences of canalithiasis or cupulolithiasis and/or semicircular canal involvement.

Study design

clinical prospective with transversal cohort.

Material and Method

Sixty patients with benign paroxysmal positional vertigo were consecutively selected according to each combination of canalithiasis or cupulolithiasis with semicircular canal involvement. Patients were treated by means of canalith repositioning procedures repeated weekly until the elimination of the positioning nystagmus. Analysis of Variance was used to verify differences between the variables.

Results

An average of 2.13 procedures (from 1 to 8) was needed to eliminate the positioning nystagmus. Canalithiasis required an average of 1.53 procedures, while cupulolithiasis needed 2.92 procedures (p = 0.0002). An average of two procedures was needed to eliminate the positioning nystagmus in cases with posterior canal involvement, 2.39 procedures in cases with anterior canal involvement and 2.07 procedures in cases with lateral canal involvement (p = 0.5213).

Conclusions

From one to eight weekly canalith repositioning procedures were needed, with an average of two, to eliminate positioning nystagmus in benign paroxysmal positional vertigo. Cupulolithiasis requires a greater number of procedures than canalithiasis to eliminate positioning nystagmus. Semicircular canal involvement didn't influence the number of therapeutic maneuvers.

Epley's canalith-repositioning manoeuvre for benign paroxysmal positional vertigo

The efficacy of the Epley's canalith-repositioning manoeuvre in the treatment of BPPV was assessed in this prospective study of 62 patients. Patients were selected based on symptoms of positional vertigo and positive Dix-Hallpike's positional test. Patients were divided into two groups; first group comprising 34 patients underwent Epley's manoeuvre alone where as the other group comprising 28 patients underwent Epley's manoeuvre along with mastoid oscillator. At the end of 1 month patients were assessed subjectively by visual analogue scale (VAS) and objectively by Dix-Hallpike's positional test. On VAS, 85.7% patients had complete resolution of symptoms of BPPV in both the groups. Objectively 88.2% did not have positional nysfagmus after 1 month in first group whereas in the second group 86% had complete response at the end of 1 month of therapy. Follow up of 6 months could be done in 38 patients, out of which 7 (18.4%) had recurrence of their symptom of vertigo and positive Dix-Hallpike's positional test, whereas one patient continued to have no relief by Epley's manoeuvre. There was no difference in subjective and objective parameters even when CRP was performed using mastoid vibrator.

[Intractable and atypical benign paroxysmal vertigo. Pathological results of high-resolution three-dimensional MR-tomography of the vestibular organ]

Benign paroxysmal positional vertigo (BPPV) is the most frequent vestibular disorder and a most common cause of dizziness and vertigo. The modern canalolithiasis theory postulates the existence of free-floating dense otolithic particles in the endolymph of the posterior semicircular canal. The symptoms were exactly described by Dix and Hallpike; BPPV is normally a self-limited disease with spontaneous recovery. There is however a small number of patients who do not respond to any treatment or who present with otolithic vertigo which does not fit all Dix-Hallpike criteria (atypical BPPV). While BPPV in its typical appearance cannot be diagnosed with radiologic imaging, the authors succeeded in identifying structural changes in the vestibular organs of patients suffering from intractable or atypical BPPV using three-dimensional magnetic resonance imaging.

[Histomorphological study of experimentally induced canalolithiasis]

Free otoconia in the posterior semicircular canal (pSCC) are regarded as the main reason for benign paroxysmal positional vertigo. We investigated the distribution of otoconia in the membranous labyrinth of guinea pigs (n = 34) after a defined rotatory/angular kinetic acceleration. The angular kinetic energy of the rotatory experiment produced a dislocation of the otoconia and sometimes of the complete gelatinous otolithic membrane of the utricular and saccular macula. The otoconia could be observed in all three semicircular canals but predominated in the dark cell areas of the utricular side of the lateral SCC. A total obstruction of the semicircular canal could never be seen. Close to the lateral crista, perilymphatic hemorrhage could frequently be observed. The saccular otoconia were located in the amalgamation between endolymphatic membrane and saccule. The results of this histological study can form the basis for different theories about the genesis of canalolithiasis and cupulolithiasis and the vertigo which accompanies them.

[Treating benign paroxysmal positional vertigo with the canalith repositioning maneuver of Epley. Our experience]

Benign Paroxysmal Positional Vertigo (BPPV) is one of the most common peripheral vestibular disorders. Particle repositioning maneuvers are simple and effective treatments for patients with BPPV. This study included 37 consecutive cases of BPPV treated with the particle repositioning maneuver of Epley. 97% of patients improved and the maneuver was well tolerated. We conclude that Epley Maneuver is safe and effective in the treatment of BPPV.

The particle repositioning maneouvre for benign paroxysmal positioning vertigo

Thirteen consecutive cases wherein Benign Paroxysmal Positional Vertigo was diagnosed are retrospectively reviewed. The Dix-Hallpike positioning test was classically positive with a typical torsional, down beating, transient nystagmus in four of these thirteen cases. The diagnosis in the other nine was based on a suggestive history with or without subjective vertigo on the positioning test. Ten cases improved with labyrinthine suppressants and habituation exercises alone. This included all the patients wherein the Dix-Hallpike maneouvre did not elicit any nystagmus. However, in the group wherein the Dix-Hallpike maneouvre resulted in nystagmus, only one of the four improved and the particle repositioning maneouvre (PRM) was employed in the three cases with persistent symptoms. Two had immediate relief of symptoms. The particle repositioning maneouvre was repeated after three days in the one other patient and proved successful on this second occasion. Surgical treatment was not necessitated in any case, It is proposed that the particle repositioning maneouvre should be the preferred first-line treatment for any patient who on Dix-Hallpike testing demonstrates nystagmus typical of BPPV.

Surgical anatomy of the singular nerve

Rare cases of chronic persistent positional vertigo do not respond to physiotherapy. For the treatment of these cases Gacek suggested singular nerve neurectomy as a new surgical procedure. The aim of the present study was to investigate the surgical anatomy of the singular nerve in order to evaluate the exact topography. In 25 cadaver temporal bones the posterior ampullary ("singular") nerve was prepared. The topographical correlation between singular nerve, posterior semicircular canal, and the round window membrane was evaluated. The average length of the nerve was 4.2 mm, its diameter 0.6 mm. The shortest distance between singular nerve and round window membrane was 0.7 mm in average, the nerve could be detected at a depth of 1.3 mm. The transtympanal access was impossible in 7 of 25 cases either because of its close relation to the round window or its direct course towards the ampulla. In only 5 of 25 cases was the nerve located sufficiently inferior in the round window niche for neurectomy. Thus, transtympanal singular nerve neurectomy can be performed only in selected cases. The presented data are helpful for preoperative and intraoperative decisions.

Basophilic deposits on the cupula: preliminary findings describing the problems involved in studies regarding the incidence of basophilic deposits on the cupula

In this study, the possibility of whether basophilic deposits adhered to the cupulas in the semicircular canals was investigated histologically. Results indicated that basophilic deposits were present in all three cupulas of the semicircular canals. The overall incidence of basophilic deposits in the superior, lateral and posterior semicircular canal cupulas was 26%, 41% and 37%, respectively. The incidence of basophilic deposits bound to the cupulas increased with age. The possible origin of these basophilic deposits on the cupulas and the increased incidence of basophilic deposits with increasing age are discussed.

Benign paroxysmal positional vertigo of the horizontal canal

OBJECTIVES

To review the clinical features, electronystagmography findings, the possible mechanism, and a possible therapeutic approach to benign paroxysmal positional vertigo (BPPV).

METHODS

Sixty-three cases of BPPV of the horizontal canal type have been reviewed. It is characterised by horizontal nystagmus and an intense vertigo, provoked by rotation of the head in a supine patient. The horizontal nystagmus beats towards the ground on both sides, becomes more pronounced when lying on the pathological side, and then the nystagmus often changes direction.

RESULTS

Forty-eight patients underwent electronystagmography. On the pathological side, the first phase nystagmus had a mean latency of three seconds and a mean duration of 31.6 seconds. Nystagmus inversion occurred in 36 patients after a nystagmus free interval. The mean second phase nystagmus duration lasted 33.4 seconds. On the healthy side, the nystagmus had a mean latency of 3.4 seconds and a mean duration of 39.5 seconds. Fatigue was seen in six patients. Simultaneous involvement of the posterior canal was present in 16 patients. A liberatory manoeuvre was successful in six patients.

CONCLUSIONS

The liberatory manoeuvre should be tried in patients with horizontal canal vertigo. It should not be performed in patients with severe cervical arthrosis, vertebrobasilar insufficiency, or when the patient has neck pain during the manoeuvre.

Randomized Trial of the Canalith Repositioning Procedure

Thirty-six subjects with confirmed, unilateral benign paroxysmal positioning vertigo of at least 2 months' duration were randomly assigned to one of two treatment groups. After complete informational counseling and explanation of the posttreatment instructions, subjects were randomly assigned to receive either Epley's canalith repositioning procedure or a placebo maneuver. All subjects completed a daily diary for 1 month to document any dizzy spells and their adherence to the posttreatment instructions. Follow-up Dix-Hallpike testing was performed after 1 month by an audiologist who was blinded to the patient's treatment group status. Analysis of Dix-Hallpike results confirmed that those who received the canalith repositioning procedure had significantly more negative responses (88.9%) than did those in the placebo group (26.7%).

Infrared/video ENG recording of positional nystagmus in subjects with peripheral vestibular disease

We performed simultaneous infrared/video and electronystagmorgraphy (ENG) recordings of eye movements in 417 patients with disequilibrium. Of that number, 54 patients with the following two criteria participated in this study: verified diagnosis of peripheral vestibular disease and the presence of positional nystagmus recorded by ENG and an infrared/ video recording system. Although horizontal nystagmus was the most common, torsional, vertical and oblique nystagmus were also demonstrated in these patients. The most striking finding was the high incidence of oblique nystagmus closely related to a significant right-left difference of the caloric response in benign positional vertigo.

Positional and positioning vertigo and nystagmus

Positional and positioning vertigo and nystagmus syndromes can be attributed to either peripheral or central vestibular dysfunction. The most common form is benign paroxysmal positioning vertigo which is caused by cupulolithiasis into the posterior semicircular canal. Other labyrinthine manifestations such as positional alcohol nystagmus, positional nystagmus with macroglobulinaemia and "heavy water" or glycerol ingestion occur because of a specific gravity differential between the cupula and the endolymph (buoyancy mechanism). Neurovascular compression of the vestibular nerve may be a causative factor for "disabling positional vertigo" which is an insufficiently described entity. Hesitation is highly justifiable since retromastoid craniectomy for microvascular decompression is the recommended management. Central positional vertigo is either induced by head movements which result in a transient ischaemia of the ponto-medullary brainstem, or by a change in head position relative to the gravitational vector. The latter is comprised of at least three forms: positional downbeat nystagmus (nodulus), positional nystagmus without concurrent vertigo, and positional vertigo with nystagmus. The site of the lesion is always near the fourth ventricle and the vestibular nuclei. The most probable explanation for the positional response is a vestibular tone imbalance caused by disinhibition of the vestibular reflexes on perception, eye, head and body position.

Further observations on posterior ampullary nerve transection for positional vertigo

An evaluation was made on ten patients with benign paroxysmal positional vertigo (BPPV) in whom transection of the posterior ampullary nerve was performed by the middle ear approach under local anesthesia. The undermost ear in the provocative test position was selected for surgery. All ten patients were relieved of positional vertigo by the procedure. Of the five patients who were relieved of BPPV by posterior ampullary nerve transection prior to 1974, the long-term follow-up on four revealed continued relief of vertigo. Five additional patients treated by this surgical procedure since 1975 have also experienced relief from BPPV, but a moderate sensorineural hearing loss occurred in one patient. Two additional patients with BPPV were explored surgically but the singular canal could not be located. Persistence of the vertigo in these two patients strengthens the conclusion that the posterior semicircular canal sense organ is largely responsible for BPPV.

Observations on normal and degenerating human otoconia

Specimens of human otoconia obtained from autopsy material and representing various stages from fetal to advanced old age, were studied by microdissection, scanning electron microscopy, electron microprobe analysis, and x-ray powder diffraction. The typical adult otoconial configuration is a cylindrical, finely serrated body with pointed ends; crystallographically, it corresponds to a single crystal of calcite. Other, less numerous typed include jointed otoconia, pure rhombohedrons and multifaceted, presumably immature forms. Many otoconia achieve the adult configuration during fetal development. The multifaceted otoconia are most numerous, and the rhombohedrons proliferate, during childhon in the young adult, but saccular otoconia are the larger. In middle and advanced age the otoconia decrease in number, especially in the saccule. Saccular otoconia degenerate progressively in a posteroanterior direction across the macula; they assume a specific, fibours, hollowed-out appearance, which is not duplicated by either chemical etching or autolysis. Neogenesis and growth of otoconia appear to occur postnatally, with different characteristic growth potentials for those of the saccule and the utricle. Age-related saccular otoconial degeneration appears to involve the organic material, which disappears either before or simultaneously with the mineral substance.

Incorporation of radioactive calcium into otolithic membranes and middle ear ossicles of the gerbil

45CaCl2 was injected into gerbils in single or multiple doses, and the resulting radioactivity in serum, otoconial CaCO3, bone samples, and selected labyrinthine epithelium was determined by liquid scintillation spectrometry. Incorporation into both utricular and saccular otoconia occurred at the rate of 0.06-0.07 nmole Ca++ per day, corresponding to a fractional rate of uptake of 0.1%. The retention of radioactivity had a half-life of approximately 11 days. The rate of incorporation of calcium for the middle ear ossicles was 5-7 times that for otoconia and was similar to that for otic capsule and skeletal bone. The level of 45Ca++ was higher in the pigmented regions of the utricular membranous wall than in the non-pigmented areas of the utricular and ampullary wall and in the stria vascularis.