Practical approach for lateral canal benign paroxysmal positional vertigo.

Benign paroxysmal positional vertigo (BPPV) of the lateral semicircular canal is a well-recognized condition, even though there are controversies about the repositioning maneuvers and their efficacy. In recent decades, several maneuvers have been proposed for treating both apogeotropic and geotropic variants of lateral canal BPPV. Our purpose is to discuss a practical approach to this pathology with the Zuma maneuver. In a single session, this maneuver may be useful to treat patients with canalithiasis of the ampullary and non-ampullary arms, and cupulolithiasis with the otoliths in the canal and utricular side of the lateral canal.

The role of the reversed nystagmus during Zuma maneuver in patients treated for geotropic lateral canal benign paroxysmal positional vertigo.

INTRODUCTION: The geotropic variant of lateral canal BPPV occurs due to free floating otoconia in the non ampullary arm of this canal. Several repositioning maneuvers were effective to treat patients with this variant. We have previously proposed that the Zuma maneuver, first described for apogeotropic lateral canal BPPV, could also be effective for the geotropic variant as we believe that adopting a single maneuver may help the neurotological clinical practice. MATERIAL AND METHODS: Fifteen patients with geotropic lateral canal BPPV were enrolled and treated with Zuma maneuver. Patients were reevaluated 1 h after a single maneuver. RESULTS: All patients showed a nystagmus beating to the affected side in step I of Zuma maneuver that reversed its direction in step II. Besides, all patients achieved immediate resolution of vertigo and positional nystagmus after the application of the maneuver. CONCLUSIONS: The reversal of the nystagmus in step II of Zuma maneuver could be considered as a good prognostic indicator of the successful of this maneuver in patients with geotropic lateral canal BPPV. Moreover, despite the small sample of patients, Zuma maneuver was effective on short-term follow up for geotropic LC-BPPV after a single application.

Three-dimensional simulations of six treatment maneuvers for horizontal canal benign paroxysmal positional vertigo canalithiasis.

BACKGROUND AND PURPOSE: Horizontal canal benign paroxysmal positional vertigo (BPPV) is the second most common variant of BPPV after posterior canal BPPV. Various liberatory maneuvers are recommended for the treatment of horizontal canal BPPV canalithiasis (hc-BPPV-ca). The aim of this study was to show how three-dimensional (3D) dynamic simulation models visualize the movement of the clot of otoconia within the canal for a better understanding of the theoretical efficacy. METHODS: Based on reconstructed magnetic resonance imaging and fluid dynamics, a 3D dynamic simulation model (as a function of time) was developed and applied. Thereby, six treatment maneuvers for hc-BPPV-ca were simulated: two types of the roll maneuver (the original 270° and the modified 360°) as well as two Gufoni and Zuma maneuvers (for geotropic and apogeotropic nystagmus). RESULTS: The simulations showed that the 360° roll maneuver and Zuma maneuver are effective treatment options for hc-BPPV-ca for debris in all locations within the canal. However, the original 270° roll maneuver will not be effective if the clot is in the ampullary arm of the horizontal canal. The Gufoni maneuver for geotropic hc-BPPV-ca is effective, whereas for apogeotropic hc-BPPV-ca there is a risk of treatment failure due to insufficient repositioning of the debris. CONCLUSIONS: The 3D simulations for movement of the otoconia clots can be used to test the mechanism of action and the theoretical efficacy of existing maneuvers for the different BPPV variants. For hc-BPPV-ca, the modified 360° roll maneuver and Zuma maneuver are theoretically efficient for all subtypes, whereas Gufoni maneuver is effective for geotropic nystagmus only.

Zuma Modified Maneuver as a Treatment to Geotropic Lateral Semicircular Canal Benign Paroxysmal Positional Vertigo.

Introduction Benign Paroxysmal Positional Vertigo (BPPV) is the most common vestibular disorder, resulting from detached otoliths that migrate to one of the semicircular canals - canalolithiasis - or one of the cupulas - cupulolithiasis. The present study is related to lateral canal BPPVs, which may be either geotropic or apogeotropic. The geotropic variant of lateral semicircular canal benign paroxysmal positional vertigo (LC-BPPV) is attributed to free floating particles in the posterior arm of the lateral semicircular canal. Objectives To verify the possibility of employing the Zuma repositioning maneuver, with a brief modification, as an alternative treatment for geotropic LC-BPPV. Methods Seven patients with geotropic LC-BPPV were enrolled and treated with the Zuma modified maneuver. Patients were reevaluated 1 hour after a single maneuver, to confirm the resolution of vertigo and positional nystagmus. Results All seven patients achieved immediate resolution of vertigo and positional nystagmus as measured 1 hour after the application of the maneuver. Conclusion The Zuma modified maneuver was effective for geotropic LC-BPPV after a single application. The use of the Zuma maneuver for both apogeotropic and geotropic LC-BPPV may simplify the treatment of these patients.

Zuma Modified Maneuver as a Treatment to Geotropic Lateral Semicircular Canal Benign Paroxysmal Positional Vertigo

Abstract Introduction Benign Paroxysmal Positional Vertigo (BPPV) is the most common vestibular disorder, resulting from detached otoliths that migrate to one of the semicircular canals - canalolithiasis - or one of the cupulas - cupulolithiasis. The present study is related to lateral canal BPPVs, which may be either geotropic or apogeotropic. The geotropic variant of lateral semicircular canal benign paroxysmal positional vertigo (LC-BPPV) is attributed to free floating particles in the posterior arm of the lateral semicircular canal. Objectives To verify the possibility of employing the Zuma repositioning maneuver, with a brief modification, as an alternative treatment for geotropic LC-BPPV. Methods Seven patients with geotropic LC-BPPV were enrolled and treated with the Zuma modified maneuver. Patients were reevaluated 1 hour after a single maneuver, to confirm the resolution of vertigo and positional nystagmus. Results All seven patients achieved immediate resolution of vertigo and positional nystagmus as measured 1 hour after the application of the maneuver. Conclusion The Zuma modified maneuver was effective for geotropic LC-BPPV after a single application. The use of the Zuma maneuver for both apogeotropic and geotropic LC-BPPV may simplify the treatment of these patients.

Corrective Saccades in Unilateral and Bilateral Vestibular Hypofunction During Slow Rotation Expressed by Visually Enhanced VOR and VOR Suppression: Role of the Cerebellum.

In clinical practice, the head impulse test paradigm (HIMP) and the suppression head impulse paradigm (SHIMP) stimulate high-frequency head movements so that the visual system is temporarily suppressed. The two tests could also be useful tools for vestibular assessment at low frequencies: VVOR (visually enhanced vestibulo-ocular reflex) and VORS (vestibulo-ocular reflex suppression). The aim of this study is to analyze the eye movements typically found during VVOR and VORS testing in patients with unilateral and bilateral vestibular hypofunction. Twenty patients with unilateral vestibular hypofunction, three patients with bilateral vestibular hypofunction, and ten patients with normal vestibular function (control group) were analyzed through VVOR and VORS testing with an Otometrics ICS Impulse system. During the VVOR test, patients with unilateral vestibular hypofunction exhibited corrective saccades to the same direction of the nystagmus fast phase toward the healthy side when the head rotates toward the affected side, while patients with bilateral vestibular hypofunction exhibited corrective saccades to the opposite side of head movements to each side. During the VORS test, patients with unilateral vestibular hypofunction seem to exhibit larger corrective saccades to the healthy side when the head was moved to this side, while patients with bilateral vestibular hypofunction did not exhibit corrective saccades during head movements to either side. Our data suggest that the VVOR and VORS tests yield the same diagnostic information as the HIMP and SHIMP tests in unilateral and bilateral vestibular hypofunction, and can contribute to the diagnosis of a peripheral vestibular loss as well as the affected side.

An Algorithm for the Diagnosis of Vestibular, Cerebellar, and Oculomotor Disorders Using a Systematized Clinical Bedside Examination.

The bedside examination associated with their clinical history remains the most critical means to accurately diagnose the cause for most of the signs and symptoms related to pathology of the cerebellum and vestibular system in patients presenting with dizziness and imbalance. This paper focuses on those critical bedside examinations, suggests when laboratory testing might be useful to confirm the clinical suspicion, and considers the shared neural circuitry within the visual and vestibular systems to offer an algorithmic approach in conducting the clinical bedside examination.

Management of Lateral Semicircular Canal Benign Paroxysmal Positional Vertigo.

Benign paroxysmal positional vertigo (BPPV) is the most common cause of peripheral vestibular vertigo. It is caused by free-floating otoconia moving freely in one of the semicircular canals (canalolithiasis) or by otoliths adhered to the cupula (cupulolithiasis). The posterior canal is the most common canal affected, followed by the lateral canal. Diagnosis of the side affected is critical for successful treatment; therefore, suppressing visual fixation is essential to examination of these patients' eye movement. On the basis of our experience, we have adopted the Zuma maneuver and the modified Zuma maneuver for both apogeotropic and geotropic variants of lateral canal BPPV. Knowledge of the anatomy and pathophysiologic mechanisms of the semicircular canals is essential for correct management of these patients. Hence, using a single maneuver and its modification may facilitate daily neurotological practice.

Apogeotropic variant of horizontal semicircular canal benign paroxysmal positional vertigo: Where are the particles?

The apogeotropic variant of horizontal semicircular canal benign paroxysmal positional vertigo (HC-BPPV) is attributed to free floating particles in the anterior arm of the lateral semicircular canal - particles attached to the cupula facing the canal or particles attached to the cupula facing the utricle. Zuma e Maia described a new treatment for both canalithiasis of the anterior arm of the horizontal semicircular canal (HC) and cupulolithiasis of the HC. Seventeen patients with apogeotropic HC-BPPV were enrolled and treated with Zuma's Maneuver. During the repositioning of the particles to the utricule, we observed the direction of the nystagmus evoked in each step of this maneuver in order to know where the otoliths were probably located. Eight patients were diagnosed with canalithiasis of the anterior arm, six patients with cupulolithiasis with the particles facing the canal and three patients with cupulolithiasis with the particles facing the utricle. Our data suggest that we can assume where the otoliths are probably located by observing the pattern of the nystagmus evoked in each step of the Zuma's Maneuver in patients with apogeotropic HC-BPPV.

Seasonality and solar radiation variation level in benign paroxysmal positional vertigo.

BACKGROUND: Several studies have shown that the incidence of benign paroxysmal positional vertigo (BPPV) presents seasonal variations and there is evidence that the variation in time is dependent on the patient's amount of vitamin D. OBJECTIVES: This is a retrospective study to verify if there is a correlation between the incidence of BPPV and the level of solar radiation, essential for the synthesis of vitamin D in the skin. MATERIAL AND METHODS: This study comprised 214 patients with BPPV seen from 2012 to 2017, in a city Latitude: -30.0277, Longitude: -51.2287 30° 1' 40″ South, 51° 13' 43″ West. The amounts of monthly solar radiation were analyzed in relation to the dates of their first consultations. Statistical tests were employed to verify the existence of a correlation between solar radiation and the incidence of the disease. RESULTS: The statistical analysis revealed a significant difference between the incidence of BPPV and the amount of radiation during the month of the diagnosis of the disease. There was also a significant statistical correlation with the climatic variation. CONCLUSION: More patients with benign paroxysmal positional vertigo (BPPV) are seen in consultation in the months with low solar radiation and in the autumn and winter seasons, in this geographic city.

Normative data for static balance testing in healthy individuals using open source computerized posturography.

PURPOSE: Computerized posturography is the gold standard for balance assessment. Because of the great cost and dimensions of commercial equipments, low-cost and portable devices have been developed and validated, such as RombergLab, a software in open source term which works connected with a low-cost force platform. The objective of this study was to obtain normative posturography data using this software. METHODS: A multicentric prospective and descriptive study, with 350 healthy participants, was designed. Static postural stability (measured using the modified clinical test of sensory interaction on balance) was evaluated using the software connected to the force platform. Using the confidence ellipse area (CEA) in each condition, global equilibrium score (GES) was calculated and adjusted for significant variable factors using cluster analysis. RESULTS: Mean (SD) GES was 0.72 (0.22). Age (p < 0.01), height (p < 0.01) and recruitment center (p < 0.05) were found as influence factors for GES. Cluster analysis obtained 16 groups stratified by age and height. GES decreases with age and height (p < 0.005). No significant interaction of age nor height was found with GES in these clusters (p > 0.05). After correction for height and age, GES was no longer influenced by the recruitment center (p > 0.05). CONCLUSIONS: With the introduction of the global equilibrium score values of the present study into the software, we consider RombergLab v1.3 a reference posturography tool for healthy individuals. Further studies are needed for validating it as a suitable instrumented test for screening between healthy and pathologic subjects and its reliability over time for the follow-up of patients.

New Treatment Strategy for Apogeotropic Horizontal Canal Benign Paroxysmal Positional Vertigo.

The apogeotropic variant of horizontal semicircular canal benign paroxysmal positional vertigo (HC-BPPV) is attributed to canalithiasis of the anterior arm or cupulolithiasis. Despite some therapeutic maneuvers, I propose a new treatment strategy for apogeotropic HC-BPPV that is designed to detach both the otoconial debris from the anterior arm of the semicircular canal and the debris that is attached to the utricular side of the cupula using inertia and gravity and based on simulations with a 3D biomechanical model.

Behavior of the Posterior Semicircular Canal After Dix-Hallpike Maneuver.

The objective of the present study is to analyze the quantitative vestibulo-ocular responses in a group of patients with benign paroxysmal positional vertigo (BPPV) canalolithiasis and compare these data with the data of the tridimensional biomechanical model. This study was conducted on 70 patients that presented idiopathic posterior semicircular canal canalolithiasis. The diagnosis was obtained by Dix-Hallpike maneuvers recorded by videonystagmograph. The present study demonstrates that there is a significant correlation between the intensity of the nystagmus and its latency in cases of BPPV-idiopathic posterior semicircular canal canalolithiasis type. These findings are in agreement with those obtained in a tridimensional biomechanical model and are not related to the patients' age.

Inferior peduncle lesion presenting with bilaterally impaired vestibular responses to horizontal and posterior head impulses.

Differentiating central from peripheral origins of vestibulo-ocular reflex (VOR) lesions can be challenging. A 36-year old man presented with a 1-year history of progressive unsteadiness. The video-Head Impulse Test revealed a significantly reduced VOR gain in both horizontal and posterior canals (0.49 ± 0.05 and 0.38 ± 0.06) but normal VOR responses in both anterior canals (0.89 ± 0.08 and 1.04 ± 0.15). No plausible combination of end-organ lesion should be responsible for these observations. A brain magnetic resonance imaging disclosed a left inferior cerebellar peduncle lesion suggestive of a glioma.

Assessment of the vestibuloocular reflex in fighter pilots with the video head impulse test.

CONCLUSION: There were no changes in the function of the six semicircular canals in active fighter pilots, through the use of the video head impulse test (vHIT). These results suggest that the vestibuloocular reflex (VOR) works well at the high frequencies related to the natural head movements in this population. OBJECTIVES/HYPOTHESIS: The vestibular function in pilots has been reported as being different from that of other normal subjects. These differences are attributed to adaptation of the vestibuloocular reflex (VOR) or by habituation. These studies were conducted with caloric and/or rotatory tests and were limited to the lateral semicircular canals. The aim of the present study was to verify the occurrence of high frequency changes in the function of the six semicircular canals in active fighter pilots, through the use of the video head impulse test (vHIT). STUDY DESIGN: Cross-sectional design. METHODS: The subjects participating in this study were divided in three groups, according to their flight experience. The control group (Group 1) consisted of 20 soldiers with no experience of in-flight training. For the test subjects 14 fighter pilots were selected and divided into two groups. Group 2 included the pilots with 1000-2000 hours of flight experience and Group 3 included pilots with 2001-3000 hours of flight experience. They were all submitted to a video head impulse test and the gains of the six semicircular canals were analysed. RESULTS: There were significantly low gain values (p < 0,013) only in the left posterior semicircular canal in the control group as compared with the subject groups. However, there were no significant differences in gain values between the two groups of the active pilots.

The video head impulse test.

CONCLUSION: Additional research is needed to validate the importance of the video head impulse tests (vHIT), but it provides an important contribution to the evaluation of anterior and posterior semicircular canal disorders. OBJECTIVES: To share observations of the vHIT test in clinical neurotology and to discuss the significance of the study findings. METHODS: This study comprised 200 patients with a clinical history of vestibular disturbances who were submitted to a vHIT including all six semicircular canals. RESULTS: Abnormal responses of the anterior and posterior canals were found in several patients, either alone or combined with altered responses in the lateral canals. A unilateral hypoactive response of a posterior canal was found in a patient with a small vestibular schwannoma.

Distortion product otoacoustic emissions in an animal model of induced hyperinsulinemia.

The existence of a relationship between abnormal insulin levels and the occurrence of labyrinth disorders has been demonstrated in several works. Among many metabolic alterations, such studies indicate that hyperinsulinemia is one of the most frequent causes of cochlear and vestibular syndromes. In this study, we monitored distortion product evoked otoacoustic emission thresholds during induced acute hyperinsulinemia in sheep so as to identify the occurrence of electrophysiological changes in cochlear outer hair cells. In the study group, seven sheep received a bolus of 0.1 U/kg of regular human insulin. In the control group, seven sheep received saline solution. We measured insulin and glucose levels simultaneously with the recording of distortion product otoacoustic emissions at 10-minute intervals over 90 minutes. We successfully induced hypoglycemia and hyperinsulinemia. We detected no changes in distortion product thresholds in the control group during the 90 minutes of the experiment. In the study group, we recorded a reduction in distortion product thresholds in relation to the control group at frequencies above 1,500 Hz and after 60 minutes (p < .001). We observed significant electrophysiological changes in cochlear outer hair cells reflected in the variation of distortion product thresholds at high frequencies after 60 minutes.