Search

This study reported a distinctive case of an adolescent diagnosed with trauma induced BPPV posed by coexisting geotropic and apogeotropic nystagmus. The discussion highlights the pathophysiology and need for repeated vestibular rehabilitation sessions of repositioning manoeuvres for complete resolution of the vertigo. [ABSTRACT FROM AUTHOR]

Intralabyrinthine schwannomas are a rare subgroup of vestibular schwannomas located within the membranous labyrinth of the inner ear and are known for their variable clinical presentations and symptoms. In the present study, we report on a patient with a persistent history of dizziness and positional vertigo, who was misdiagnosed with posterior canalithiasis. As hearing loss was not developed until late in the disease course, the patient was not properly diagnosed until magnetic resonance imaging revealed an intralabyrinthine schwannoma, which was not discovered on earlier imaging. In addition to the unusual clinical presentation, we describe the audio-vestibular profile of our patient. We suggest that a thorough vestibular evaluation, including caloric testing and a careful examination of the inner ear on imaging, is warranted in cases of treatment of refractory vertigo, even in patients where a diagnosis seems certain. [ABSTRACT FROM AUTHOR]

Canalithiasis is a common vestibular system disorder, which may lead to a specific form of vertigo known as BPPV or top-shelf vertigo. In this paper, based on the actual geometric parameters of the human semicircular canal, we designed a four-fold in vitro one-dimensional semicircular canal model using technologies such as three-dimensional printing, image processing, and target tracking. We investigated the essential characteristics of the semicircular canal, such as the time constant of the cupula and the relationship between the number, density, and size of the canalith and the cupular deformation during canalith settlement. The results showed a linear relationship between the number and size of the canalith and the amount of cupular deformation. We also found that when the number of canaliths reached a particular scale, the interaction between the canaliths exerted an additional disturbance on the cupular deformation ("Z" twist). In addition, we explored the latency time of the cupula during canalith settlement. Finally, we verified that the canaliths had little effect on the frequency characteristics of the semicircular canal by a sinusoidal swing experiment. All the results validate the reliability of our 4-fold in vitro one-dimensional semicircular canal model. [ABSTRACT FROM AUTHOR]

Benign paroxysmal positional vertigo (BPPV) is the peripheral vestibular disorder that is most frequently encountered in routine neuro-otological practice. Among the three semicircular canals, the lateral semicircular canal (LSC) is the second most frequently interested in the pathological process. In most cases, LSC BPPV is attributable to a canalithiasis or cupulolithiasis mechanism. The clinical picture of LSC BPPV is that of positional nystagmus and vertigo evoked by turning the head from the supine to the side lateral position. With such a movement, a horizontal positional (and often also paroxysmal) direction-changing nystagmus is generated. Depending on whether the pathogenetic mechanism is that of canalithiasis or cupulolithiasis and depending on where the dense particles are located, LSC BPPV direction-changing positional nystagmus is geotropic or apogeotropic on both lateral sides. Due to its mechanical nature, BPPV is effectively treated by means of physical therapy. In the case of a LSC BPPV, one of the most effective therapies is the forced prolonged position (FPP), in which the patient is invited to lie for 12 h on the lateral side on which vertigo and nystagmus are less intense, to move the canaliths out from the canal (or to shift them inside of the canal from one tract to another) exploiting the force of gravity. Despite its efficacy, FPP is not always well tolerated by every patient, and it cannot be done during the diagnostic session because of its duration. The present study aimed to verify the efficacy of a different forced position, shortened forced position (SFP), with respect to the original FPP. SFP treatment would allow patients to more easily bear the forced position and physicians to control the outcome almost immediately, possibly enabling them to dismiss patients without vertigo. After 1 h of lying on the side where vertigo and nystagmus are the less intense, 38 out of 53 (71.7%) patients treated with SFP were either healed or improved. Although the outcomes are not as satisfying as those of the original FPP, SFP should be considered as a therapeutic prospect, especially by those physicians who work in collaboration with emergency departments or otherwise encounter acute patients to cure them of vertigo as soon as possible.

ObjectiveThe aim of this study was to observe the 3-dimensional (3D; horizontal, vertical, and torsional) characteristics of nystagmus in patients with posterior semicircular canal canalithiasis (PSC-can)–related benign paroxysmal positional vertigo (BPPV) and investigate its correlation with Ewald’s.MethodsIn all, 84 patients with PSC-can were enrolled. The latency, duration, direction, and slow-phase velocity induced by the Dix-Hallpike test in the head-hanging and sitting positions were recorded using 3D video nystagmography (3D-VNG). The characteristics of the horizontal, vertical, and torsional components of nystagmus were quantitatively analyzed.Results3D-VNG showed that the fast phase of the vertical components and torsional components of left and right ear PSC-can as induced by the head-hanging position of the Dix-Hallpike test were upward, clockwise and counterclockwise, and horizontal components were mainly contralateral. The median slow-phase velocity of each of the three components for consecutive 5 s was 26.3°/s (12.3–45.8), 25.0°/s (15.7–38.9), and 9.2°/s (4.9–13.7). When patients were returned to the sitting position, the fast phase of the vertical and torsional components of nystagmus was reversed. Only 54 patients had horizontal components of nystagmus, and 32 of them remained in the same direction. The median slow-phase velocity of the three components for consecutive 5 s was 9.4°/s (6.0–11.7), 6.8°/s (4.5–11.8), and 4.9°/s (2.8–8.0). The ratios of the slow-phase velocity of the horizontal, vertical, and torsional components of the head-hanging position to the sitting position were close to 1.85 (1.0–6.6), 3.7 (1.9–6.6), and 5.1 (2.6–11.3). The ratios of the slow-phase velocity of the vertical to horizontal component, the torsional to horizontal component, and the vertical to torsional component of the head-hanging position were close to 3.3 (1.7–7.6), 3.9 (1.8–7.6), and 1.0 (0.5–1.8). The ratios of the slow-phase velocity of the vertical to horizontal component, the torsional to horizontal component, and the vertical to torsional component of the sitting position were close to 2.1 (1.1–6.8), 1.5 (1.0–3.8), and 1.2 (0.8–2.8).ConclusionThere were three components of nystagmus induced by the Dix-Hallpike test in patients with PSC-can. The vertical component was the strongest and the horizontal component was the weakest. The 3D characteristics of nystagmus were consistent with those of physiological nystagmus associated with the same PSC with a single-factor stimulus, in accordance with Ewald’s law.

Background and Objectives: The aim of this study was to show with three-dimensional simulations how the diagnostic supine roll test (SRT) is affected by the initial position of the debris within the horizontal canal (hc) and study the nystagmus patterns on changing the sequence of testing and its impact on the diagnosis of the side of involvement in hc-BPPV. Methods: A 3D dynamic simulation model was developed and applied based on reconstructed MRI images and fluid dynamics. Each semicircular canal was linked to the respective extraocular muscles to visualize nystagmus generated on stimulation of the canal. Results: The simulations of hc-canalithiasis showed that the nystagmus pattern seen with the SRT is changed by the initial position of the otolith debris within the canal and the sequence of testing. The debris changes position during SRT so that sequential steps do not start at the initial position as previously assumed. The sequence of performing the SRT steps from the right or left side influences the nystagmus pattern generated: bilateral direction-changing, bilateral direction-fixed, and unilateral nystagmus can be seen in different test conditions. The SRT itself may even reposition the debris out of the canal. Conclusions and Clinical Implications: Simulations provide a dynamic tool to study the diagnostic SRT in hc-canalithiasis. Starting the SRT from right or left has a major impact on the test outcome (unlike the Dix-Hallpike maneuver). The findings provide a new interpretation for the results of the SRT. The simulations explain the phenomenon of direction-fixed nystagmus as a logical consequence of starting the SRT with the head turned toward the non-affected side in hc-canalithiasis with debris in the ampullary arm. They also show that unilateral nystagmus seen on SRT indicates canalithiasis of the non-ampullary arm of the side opposite to the side of nystagmus. The generation of bilateral direction-changing, bilateral direction-fixed, and unilateral nystagmus can be the cause of misdiagnoses in terms of the affected side and underlying mechanisms. Finally, a recommendation for a standardized protocol for the sequence of positional tests should be established to ensure uniform interpretation of test results. [ABSTRACT FROM AUTHOR]

To date, along with the progress of new technology and computer program development, the high-resolution computed tomography (HRCT) had been applied in different clinical application, such as HRCT for coronary angiography. In the current neuroimaging reports, we present HRCT images of the head/neck of two cases, in which one had a diagnosis of benign paroxysmal positional vertigo (BPPV) and the other did not, to represent the Tyndall effect, which describes the scattering of light by particles (i.e., semicircular canalolithiasis) in the path of light and enables clinicians to see a specific signal on the HRCT images. On the HRCT image of the patient with canalolithiasis with BPPV, we could obviously see the scattering effect (i.e., Tyndall effect) in the horizontal/posterior semicircular canal; however, on the HRCT image of the other without canalolithiasis, we could not see such findings. Therefore, through the assistance of technological progress, HRCT might be beneficial in the diagnosis of semicircular canalolithiasis, which has the advantage of being noninvasive and having a low risk of complications. However, because of the disadvantages of expense and risk of radiation exposure, HRCT should be reserved for patients who are difficult to diagnose. [ABSTRACT FROM AUTHOR]

Background and ObjectivesThe aim of this study was to show with three-dimensional simulations how the diagnostic supine roll test (SRT) is affected by the initial position of the debris within the horizontal canal (hc) and study the nystagmus patterns on changing the sequence of testing and its impact on the diagnosis of the side of involvement in hc-BPPV.MethodsA 3D dynamic simulation model was developed and applied based on reconstructed MRI images and fluid dynamics. Each semicircular canal was linked to the respective extraocular muscles to visualize nystagmus generated on stimulation of the canal.ResultsThe simulations of hc-canalithiasis showed that the nystagmus pattern seen with the SRT is changed by the initial position of the otolith debris within the canal and the sequence of testing. The debris changes position during SRT so that sequential steps do not start at the initial position as previously assumed. The sequence of performing the SRT steps from the right or left side influences the nystagmus pattern generated: bilateral direction-changing, bilateral direction-fixed, and unilateral nystagmus can be seen in different test conditions. The SRT itself may even reposition the debris out of the canal.Conclusions and Clinical ImplicationsSimulations provide a dynamic tool to study the diagnostic SRT in hc-canalithiasis. Starting the SRT from right or left has a major impact on the test outcome (unlike the Dix-Hallpike maneuver). The findings provide a new interpretation for the results of the SRT. The simulations explain the phenomenon of direction-fixed nystagmus as a logical consequence of starting the SRT with the head turned toward the non-affected side in hc-canalithiasis with debris in the ampullary arm. They also show that unilateral nystagmus seen on SRT indicates canalithiasis of the non-ampullary arm of the side opposite to the side of nystagmus. The generation of bilateral direction-changing, bilateral direction-fixed, and unilateral nystagmus can be the cause of misdiagnoses in terms of the affected side and underlying mechanisms. Finally, a recommendation for a standardized protocol for the sequence of positional tests should be established to ensure uniform interpretation of test results.

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. [ABSTRACT FROM AUTHOR]

Objective: To evaluate horizontal semicircular canal (HSC) effects according to Ewald's law and nystagmus characteristics of horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV) in the supine roll test.Methods: Patients with HSC-BPPV (n = 72) and healthy subjects (n = 38) were enrolled. Latency, duration, and intensity of nystagmus elicited by supine roll test were recorded using video nystagmography.Results: In patients with HSC-BPPV, horizontal nystagmus could be elicited by right/left head position (positional nystagmus) and during head-turning (head-turning nystagmus), and nystagmus direction was the same as that of head turning. Mean intensity values of head-turning nystagmus in HSC-BPPV patients were (44.70 ± 18.24)°/s and (44.65 ± 19.27)°/s on the affected and unaffected sides, respectively, which was not a significant difference (p = 0.980), while those for positional nystagmus were (40.81 ± 25.56)°/s and (17.69 ± 9.31)°/s (ratio, 2.59 ± 1.98:1), respectively, representing a significant difference (p < 0.0001). There was no positional nystagmus in 49 HSC-BPPV patients after repositioning treatment, nor in the 38 healthy subjects. No significant difference in head-turning nystagmus was detected in HSC-BPPV patients with or without repositioning.Conclusions: The direction and intensity of nystagmus elicited by supine roll test in patients with HSC-BPPV, was broadly consistent with the physiological nystagmus associated with a same HSC with single factor stimulus. Our findings suggest that HSC-BPPV can be a show of Ewald's law in human body.

Objective: To evaluate horizontal semicircular canal (HSC) effects according to Ewald's law and nystagmus characteristics of horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV) in the supine roll test. Methods: Patients with HSC-BPPV (n = 72) and healthy subjects (n = 38) were enrolled. Latency, duration, and intensity of nystagmus elicited by supine roll test were recorded using video nystagmography. Results: In patients with HSC-BPPV, horizontal nystagmus could be elicited by right/left head position (positional nystagmus) and during head-turning (head-turning nystagmus), and nystagmus direction was the same as that of head turning. Mean intensity values of head-turning nystagmus in HSC-BPPV patients were (44.70 ± 18.24)°/s and (44.65 ± 19.27)°/s on the affected and unaffected sides, respectively, which was not a significant difference (p = 0.980), while those for positional nystagmus were (40.81 ± 25.56)°/s and (17.69 ± 9.31)°/s (ratio, 2.59 ± 1.98:1), respectively, representing a significant difference (p < 0.0001). There was no positional nystagmus in 49 HSC-BPPV patients after repositioning treatment, nor in the 38 healthy subjects. No significant difference in head-turning nystagmus was detected in HSC-BPPV patients with or without repositioning. Conclusions: The direction and intensity of nystagmus elicited by supine roll test in patients with HSC-BPPV, was broadly consistent with the physiological nystagmus associated with a same HSC with single factor stimulus. Our findings suggest that HSC-BPPV can be a show of Ewald's law in human body. [ABSTRACT FROM AUTHOR]

Introduction/Objective: Multiple canal BPPV can be a diagnostic challenge to the clinician. This is due in part to the complex anatomy of the labyrinth but also to complex and often simultaneous ocular responses that result from stimulation of multiple canals during traditional diagnostic testing. Our objective was to analyze the Dix-Hallpike maneuver used in the diagnosis of BPPV to look for patterns of simultaneous canal response and to develop a diagnostic maneuver that will allow separation of canal responses in multiple canal BPPV. Methods: A previously created and published 3D biomechanical model of the human labyrinths for the study of BPPV was used to analyze and compare the position and movement of otoliths in the Dix-Hallpike maneuver as well as in a proposed expanded version of the traditional Dix-Hallpike maneuver. Results: The traditional Dix-Hallpike maneuver with the head hanging may promote movement of otoliths in 5 of the six semicircular canals. The Dix-Hallpike maneuver with the head lowered only to the horizontal position allows for otoconia in only the lowermost posterior canal to fall to the most gravity dependent position. This position allows for minimal or no movement of otoconia in the contralateral posterior canal, or in either superior canal. Turning the head ninety degrees to the opposite side while still in the horizontal position will provoke otolith movement in only the contralateral posterior canal. The superior canals can then be examined for free otolith debris by extending the neck to a head-hanging position. These positions may be assumed directly from one to the next in the lying position. There seems to be no advantage to sitting up between positions. Conclusion: The Dix–Hallpike maneuver may cause simultaneous movement of otoliths present in multiple canals and create an obstacle to accurate diagnosis in multi-canal BPPV. An expanded Dix-Hallpike maneuver is described which adds intermediate steps with the head positioned to the right and left in the horizontal position before head-hanging. This expanded maneuver has helped to isolate affected semi-circular canals for individual assessment in multiple canal BPPV.

We report a case of non-traumatic, multicanal benign paroxysmal positional vertigo (BPPV) in a premenopausal, osteopenic 35-year-old female with corresponding low bone mineral density. Dix-Hallpike and supine roll tests confirmed unilateral posterior canal (PC) BPPV from 2012-2014, and later, a rare presentation of multicanal BPPV with specifically ipsilateral horizontal canals (HC) and anterior canals (AC) affected in 2015. Heel scans displayed T-scores within the osteopenia range in 2012 until levels normalized one year later. Despite treatment with indicated canalith repositioning treatments (CRTs), symptoms continued to persist. Complete resolution of symptoms occurred in 2016, which is most likely due to self-treatment with daily 5000 IU vitamin D in 2015. This case emphasizes the rare presentation of unilateral single-canal BPPV to multi-canal BPPV, along with the importance of vitamin D treatment in preventing the recurrence of symptoms., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Abedi et al.)

BACKGROUND: Benign paroxysmal positional vertigo (BPPV) is the most common vestibular disorder affecting about 20% of dizzy patients. Early diagnosis and treatment can improve the quality of life for patients. OBJECTIVE: We reviewed the classifications of different subtypes of benign paroxysmal positional vertigo and the problems we encountered using the diagnostic criteria of the Bárány Society. METHODS: Both the Dix–Hallpike maneuver and supine roll test were performed on 568 patients, and diagnoses were made based on patient history and the type of provoked nystagmus (if any). Next, the numbers of patients with each subtype and other parameters, including age and sex, were analyzed. RESULTS: Posterior semicircular canal BPPV (pc-BPPV) accounted for the largest proportion, followed by horizontal semicircular canal BPPV (hc-BPPV). Both anterior canal BPPV and multiple canal lithiasis BPPV were rare, and no patient was diagnosed with cupulolithiasis of the posterior canal. CONCLUSIONS: pc-BPPV, hc-BPPV, and cupulolithiasis of the horizontal canal (hc-BPPV-cu) were the three major subtypes that could be definitively diagnosed, whereas the diagnoses of possible benign paroxysmal positional vertigo (pBPPV) and probable benign paroxysmal positional vertigo [spontaneously resolved] (pBPPVsr) require further investigation, with special attention being paid to appropriate differentiation and repositioning maneuvers. [ABSTRACT FROM AUTHOR]

Background and Purpose: Deciphering the cause for a persistent, direction-changing geotropic nystagmus can be difficult. Migraine and light cupula are two possible causes, though can be confused with benign paroxysmal positional vertigo (BPPV) affecting the horizontal semicircular canal. In migraine, the persistent geotropic nystagmus tends to be slow; in light cupula, the nystagmus has been illustrated to beat in the direction opposite that of prone positioning. Case Description: Here we describe a patient with initial occurrence then recurrence of a high velocity (≥30 deg/sec), persistent direction-changing geotropic nystagmus and vertigo with an intensity variable based on head position, which was difficult to manage. This patient did not have migraine. The case presented uniquely as it was unlikely due to canalithiasis of the horizontal semicircular canal yet the presentation was not clearly related to the light cupula phenomena either. Intervention: In this case, the physical therapist attempted to use the barbeque roll canalith repositioning maneuver (CRM) even though the direction-changing geotropic nystagmus was persistent. The nystagmus did not resolve during the clinic visit. Outcomes and Discussion: The persistent, high velocity geotropic nystagmus resolved within 1 week, however, this resolution was likely spontaneous and not due to the CRM intervention. Our case suggests that physical therapists assessing persistent geotropic nystagmus should wait long enough for the nystagmus to stop (~2 minutes), test for fatigue by repeating the positional nystagmus tests, incorporate a head flexion component as part of the positional testing, and attempt to identify a null point. [ABSTRACT FROM AUTHOR]

Background: The Epley maneuver is generally considered to be the preferred initial treatment for canalithiasis of the posterior semicircular canal. Although the Semont maneuver was originally developed to treat patients with posterior canal cupulolithiasis, several studies have demonstrated successful outcomes when the Semont maneuver is used to treat patients with posterior canal canalithiasis. Objectives: The purpose of this systematic review was to evaluate the effectiveness of the Semont maneuver to treat canalithiasis of the posterior semicircular canal as compared to that of the Epley maneuver. Methods: Applicable research articles were obtained through a literature search of the Cumulative Index to Nursing and Allied Health Literature Complete, ProQuest Medical Library, and PubMed databases using the search terms ‘Semont’ AND ‘Epley’ AND ‘randomized’ AND ‘positional vertigo’ OR ‘positioning vertigo’ OR ‘positional nystagmus’ OR ‘positioning nystagmus.’ The Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence was used to assess the evidence level for all of the included studies, and the PEDro Scale was used to assess the methodological rigor for all of the included studies. Results: Six studies were ultimately included in the qualitative synthesis. In four of these studies, no statistically significant difference was identified between the Semont maneuver and the Epley maneuver. Conclusions: In most cases, the Semont maneuver was equally as effective as the Epley maneuver at treating posterior canal canalithiasis. In addition, the Semont maneuver should be considered as an alternative treatment option for patients with certain types of cervical, lumbar, cardiac, or respiratory pathologies. [ABSTRACT FROM AUTHOR]

Background and aim Chronic musculoskeletal pain, e.g. whiplash associated disorders (WAD), fibromyalgia and myalgia, causes significant burden on both the individual and on society as a whole. In a previous study, the authors concluded that there is a likely connection between chronic benign paroxysmal positional vertigo (BPPV)/canalithiasis and headache, neck pain, generalized pain, fatigue, cognitive dysfunctions as well as tinnitus. The balance dysfunction in BPPV/canalithiasis is dynamic and not static. This leads to a perpetual postural mismatch. The vicious cycle of a disturbed equilibrium control system may be the driving force behind the vicious cycle of pain. The aim of this study is to investigate if otolith-repositioning manoeuvres in patients with chronic BPPV/canalithiasis can be beneficial. Methods During a period of about two years a prospective observational study on patients with chronic musculoskeletal pain referred for physiotherapy was performed. Those with a Dizziness Handicap Inventory (DHI) inquiry score above 20 underwent further investigations to diagnose chronic BPPV/canalithiasis. Diagnostic criteria : (A) The diagnosis of BPPV/canalithiasis was confirmed with the following: (1) specific history of vertigo or dizziness provoked by acceleration/deceleration, AND (2) nystagmus and symptoms during at least one of the test positions; (B) the disorder had persisted for at least one year. Specific otolith repositioning manoeuvre for each semi-circular canal (SCC) was performed. Symptom questionnaire (“yes” or “no” answers during a personal interview) and a follow-up questionnaire were used. Results The responders of the follow-up questionnaire constituted the study group. Thirty-nine patients responded (i.e. 87%) (31 females, 8 males) with a median age of 44 years (17–65). The median duration of the disease was 5 years. Seventy-nine percent had a history of head or neck trauma. The DHI median score was 48 points (score >60 indicates a risk of fall). The video-oculography confirmed BPPV/canalithiasis in more than one semi-circular canal in all patients. In the present study the frequency of affected anterior semi-circular canal (SSC) was at a minimum of 26% and could be as high as 65%. Ninety-five percent suffered from headache, 92% from neck pain, 54% had generalized pain, and 56% had temporo-mandibular joint region pain. Fatigue (97%), aggravation by physical exertion (87%), decreased ability to concentrate (85%) as well as visual disturbances (85%) were the most frequently reported symptoms, and 49% suffered from tinnitus. The median number of otolith repositioning manoeuvres done was six (2–29). Median time span between finishing otolith repositioning manoeuvres and answering the questionnaire was 7 months. Effects of treatment and conclusion The present study has shown that repositioning of otoliths in the SCCs in nearly all patients with chronic BPPV/canalithiasis ameliorated pain and other symptoms. The correlation between vertigo/dizziness and the majority of symptoms was significant. Therefore, there is strong evidence to suggest that there is a connection between chronic BPPV/canalithiasis and chronic pain as well as the above-mentioned symptoms. Implications Patients with unexplained pain conditions should be evaluated with the Dizziness Handicap Inventory-questionnaire, which can identify treatable balance disorders. [ABSTRACT FROM AUTHOR]

In our daily life, small flows in the semicircular canals (SCCs) of the inner ear displace a sensory structure called the cupula which mediates the transduction of head angular velocities to afferent signals. We consider a dysfunction of the SCCs known as canalithiasis. Under this condition, small debris particles disturb the flow in the SCCs and can cause benign paroxysmal positional vertigo (BPPV), arguably the most common form of vertigo in humans. The diagnosis of BPPV is mainly based on the analysis of typical eye movements (positional nystagmus) following provocative head maneuvers that are known to lead to vertigo in BPPV patients. These eye movements are triggered by the vestibulo-ocular reflex, and their velocity provides an indirect measurement of the cupula displacement. An attenuation of the vertigo and the nystagmus is often observed when the provocative maneuver is repeated. This attenuation is known as BPPV fatigue. It was not quantitatively described so far, and the mechanisms causing it remain unknown. We quantify fatigue by eye velocity measurements and propose a fluid dynamic interpretation of our results based on a computational model for the fluid-particle dynamics of a SCC with canalithiasis. Our model suggests that the particles may not go back to their initial position after a first head maneuver such that a second head maneuver leads to different particle trajectories causing smaller cupula displacements. [ABSTRACT FROM AUTHOR]

Direction changing horizontal positional nystagmus can be observed in a variety of central and peripheral vestibular disorders. We tested sixty subjects with horizontal positional nystagmus and vertigo on the Epley Omniax rotator. Monocular video recordings were performed with the right or left ear down, in the supine and prone positions. Nystagmus slow-phase velocity (SPV) was plotted as a function of time. Thirty-one subjects diagnosed with horizontal canalolithiasis had paroxysmal horizontal geotropic nystagmus with the affected ear down (onset 0.8 ± 1 s, range 0-4.9 s, duration 11.7-47.9 s, peak SPV 79 ± 67°/s). The SPV peaked at 5-20 s and declined to 0 by 60 s; at 40 s from onset, the average SPV was 1.8 % of the peak. Nine subjects diagnosed with cupulolithiasis had persistent apogeotropic horizontal nystagmus (onset 0.7 ± 1.4 s, range 0-4.3 s). Peak SPV was 54.2 ± 31.8°/s and 26.6 ± 12.2°/s with unaffected and affected ears down, respectively. At 40 s, the average SPV had decayed to only 81 % (unaffected ear down) and 65 % (affected ear down) of the peak. Twenty subjects were diagnosed with disorders other than benign positional vertigo (BPV) [vestibular migraine (VM), Ménière's Disease, vestibular schwannoma, unilateral or bilateral peripheral vestibular loss]. Subjects with VM ( n = 13) had persistent geotropic or apogeotropic horizontal nystagmus. On average, at 40 s from nystagmus onset, the SPV was 61 % of the peak. Two patients with Ménière's Disease had persistent apogeotropic horizontal nystagmus; the peak SPV at 40 s ranged between 28.6 and 49.5 % of the peak. Symptomatic horizontal positional nystagmus can be observed in canalolithiasis, cupulolithiasis and diverse central and peripheral vestibulopathies; its temporal and intensity profile could be helpful in the separation of these entities. [ABSTRACT FROM AUTHOR]

BPPV when diagnosed before any repositioning procedure is called primary BPPV. Primary BPPV canalithiasis treatment with repositioning procedures sometimes results in unintentional conversion of BPPV form: transitional BPPV. Objectives were to find transitional BPPV forms, how they influence relative rate of canal involvement and how to be treated. This study is a retrospective case review performed at an ambulatory, tertiary referral center. Participants were 189 consecutive BPPV patients. Main outcome measures were detection of transitional BPPV, outcome of repositioning procedures for transitional canalithiasis BPPV and spontaneous recovery for transitional cupulolithiasis BPPV. Canal distribution of primary BPPV was: posterior canal (Pc): 85.7 % (162/189), horizontal canal (Hc): 11.6 % (22/189), anterior canal (Ac): 2.6 % (5/189); taken together with transitional BPPV it was: Pc: 71.3 % (164/230), Hc: 26.5 % (61/230), Ac: 2.2 % (5/230). Transitional BPPV forms were: Hc canalithiasis 58 % (24/41), Hc cupulolithiasis 37 % (15/41) and common crux reentry 5 % (2/41). Treated with barbecue maneuver transitional Hc canalithiasis cases either resolved in 58 % (14/24) or transitioned further to transitional Hc cupulolithiasis in 42 % (10/24). In follow-up of transitional Hc cupulolithiasis we confirmed spontaneous recovery in 14/15 cases in less than 2 days. The most frequent transitional BPPV form was Hc canalithiasis so it raises importance of barbecue maneuver treatment. Second most frequent was transitional Hc cupulolithiasis which very quickly spontaneously recovers and does not require any intervention. The rarest found transitional BPPV form was common crux reentry which is treated by Canalith repositioning procedure. Transitional BPPV taken together with primary BPPV may decrease relative rate of Pc BPPV, considerably increase relative rate of Hc BPPV and negligibly influence relative rate of Ac BPPV. Transitional BPPV forms can be produced by repositioning maneuvers (transitional Hc cupulolithiasis) or by the subsequent controlling positional test (transitional Hc canalithiasis and common crux reentry); underlying mechanisms are discussed. [ABSTRACT FROM AUTHOR]

SUMMARY We propose to couple the method of fundamental solutions (MFS) to the force coupling method (FCM). The resulting method is an efficient, easy to program, meshless method for flows at low Reynolds numbers with finite-size particles. In such an approach, the flow domain is extended across the solid particle phase, and the flow is approximated by a superposition of singular Stokeslets positioned outside the flow domain and finite-size multipoles collocated with the particle. To improve the efficiency of the coupling, we propose new MFS quadratures for the computation of the volume integrals required for the FCM. These are exact and do not require the expensive evaluation of Stokeslets. The proposed method has been developed in the context of investigations of the fluid dynamics of canalithiasis, that is, a pathological condition of the semicircular canals of the inner ear. Numerical examples are presented to illustrate the applicability of the method. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective. The purpose of this study is to evaluate the effects of betahistine in addition to Epley maneuver on the quality of life of patients with posterior semicircular canal benign paroxysmal positional vertigo (BPPV) of the canalithiasis type.Study Design. Double-blind, randomized, controlled clinical trial.Setting. Academic university hospital.Subjects and Methods. Seventy-two patients were enrolled in the study. The first group was treated with Epley maneuver only. The second group received placebo drug 2 times daily for 1 week in addition to Epley maneuver, and the third group received 24 mg betahistine 2 times daily for 1 week in addition to Epley maneuver. The effectiveness of the treatments was assessed in each group as well as between them by analyzing and comparing data of 4 different vertigo symptom scales.Results. Epley maneuver, alone or combined with betahistine or placebo, was found to be very effective with a primary success rate of 86.2%. The symptoms were significantly reduced in group 3 patients overall, and those patients younger or older than 50 years of age who had hypertension, with symptom onset <1 month, and with attack duration of less than a minute did significantly better with the combination of betahistine 48 mg daily.Conclusion. Betahistine in addition to Epley maneuver is more effective than Epley maneuver alone or combined with placebo with regard to improvement of symptoms in certain patients. However, future clinical studies covering more patients to investigate the benefit of medical treatments in addition to Epley maneuver are needed. [ABSTRACT FROM PUBLISHER]

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. [ABSTRACT FROM AUTHOR]

Abstract Benign paroxysmal positional vertigo (BPPV) of the anterior semicircular canal (ASC) is an uncommon disorder currently diagnosed with the Dix-Hallpike (D-H) examination. According to the literature, nystagmus and vertigo may be more pronounced when the affected ear is either up or down. In some patients, both right and left D-H tests can trigger nystagmus with the same direction. The proposed treatment options with the addition of a different manoeuvre applied by the authors of the present study in cases of ASC lithiasis, seem to present a respective variety regarding the position of the affected ASC during the procedure of canalith repositioning. The aim of this study is to analyse the mechanisms underlying both the proposed treatment options and the clinical findings in the D-H examination. The results of this analysis stimulate further investigation, since they probably imply that repositioning manoeuvres might vary in their effectiveness when applied to different clinical subgroups of ASC BPPV. Sumario El vértigo postural paroxístico benigno (BPPV) del canal semicircular anterior (ASC) es un desorden poco común que actualmente se diagnostica mediante la prueba de Dix-Hallpike (D-H). De acuerdo con la literatura, el nistagmus y el vértigo pueden ser más pronunciados cuando el oído afectado está tanto arriba como abajo. En algunos pacientes, la maniobra de D-H a la derecha como a la izquierda pueden desencadenar nistagmus con la misma dirección. Las opciones de tratamiento propuestas con la adición de una maniobra diferente aplicada por los autores de este estudio en casos de litiasis del ASC, parece presentar una variedad respectiva de acuerdo a la posición del ASC afectado durante el procedimiento de reposición canalicular. El propósito de este estudio es analizar los mecanismos subyacentes tanto de las opciones terapéuticas propuestas como de los hallazgos clínicos de la prueba D-H. Los resultados de este análisis estimulan una mayor investigación puesto que probablemente impliquen que la efectividad de las maniobras de reposicionamiento puede variar cuando se aplican a diferentes subgrupos clínicos de ASC BPPV. [ABSTRACT FROM AUTHOR]

Abstract: We present an experimental model for a semicircular canal with canalithiasis. Canalithiasis is a pathological condition where free-floating particles disturb the flow field in the semicircular canals. It may lead to a specific form of vertigo known as BPPV or top-shelf vertigo. A careful scaling of the physical and geometrical parameters allows us to study the mechanics of this disease on an enlarged model of a single semicircular canal with laser vibrometry and video particle tracking. Early results confirm the proper operation of the model canal and support the current theories on the mechanisms of BPPV. [Copyright &y& Elsevier]

The patient, a 45-year-old female with Ménière's disease, was submitted to endolymphatic sac surgery because of frequent spells of vertigo. The day after surgery she became dizzy and lost the hearing in the operated ear. She presented with a brisk nystagmus towards the healthy ear; however, a remaining vestibular function on the operated side was still present. The head impulse test was normal and in the positioning test, when turning to the operated ear, the spontaneous nystagmus was replaced by a transient horizontal nystagmus in the opposite direction. It is likely that this geotropic nystagmus was elicited from the operated ear because of debris that had accumulated in the lateral semicircular canal. Due to a suspicion of post surgical edema, the patient was treated with prednisolone, but the progression of the lesion could not be arrested. The signs of canalithiasis disappeared, but the head impulse test became pathologic as did the caloric reaction. The patient remained deaf in the operated ear. [ABSTRACT FROM AUTHOR]

Benign paroxysmal positional vertigo (BPPV) is a high-prevalence vestibular end-organ disorder caused by the detachment of utricular otoconia which float in the posterior or lateral semicircular canal. In the majority of cases the etiology of BPPV is unknown and it may follow viral infection, vascular disorders or head trauma. BPPV may be recurrent, with some authors demonstrating a correlation between recurrence and female gender. We report herein on ten cases (out of 289 diagnoses of BPPV) of recurrent idiopathic BPPV, occurring in healthy women receiving oral contraceptive treatment, which ceased after treatment suspension. It has been hypothesized that the impaired water and electrolyte balance, the variations of endolymphatic pH and the impairment of glucose or lipid metabolism induced by oral contraceptive treatment may cause otoconial degeneration and subsequent otoconia detachment and BPPV. The rarity of the finding (10/289) could account for the poor attention paid to the hormonal pathogenesis of BPPV. [ABSTRACT FROM AUTHOR]

Benign positional vertigo (BPV) is caused by detached otolith debris that enters the semicircular canal and moves with changes in head position. Movement in the plane of the affected canal triggers brief but violent episodes of vertigo. The posterior semicircular canal variant (PC-BPV) is by far the most common because once the debris enters the canal it becomes trapped and can remain there for months and even years. We are just beginning to understand how the otolithic membrane is formed, how it is maintained and what happens to otolithic debris floating in the endolymphatic space. [ABSTRACT FROM AUTHOR]

The existence of horizontal canal benign positional vertigo (BPV) was predicted from temporal hone studies in 1973, but was not clinically confirmed until later. In this series of 300 patients with BPV, 35 (12%) were identified as having the horizontal canal variant. The essential features are the onset of vertigo when the patient assumes a supine position and bidirectional horizontal nystagmus as the head is turned from side to side. In one third it appeared as a canal ‘conversion’ in patients undergoing repositioning treatment for posterior canal BPV. The mechanism can be canalithiasis or cupulolithiasis. Repositioning treatment is a 360° horizontal head and body rotation that has a high success rate if the symptomatic ear is correctly identified. [ABSTRACT FROM AUTHOR]

Objectives To demonstrate that for treatment of benign positional vertigo it is not necessary to identify a positional nystagmus. Study Design Prospective trial of 43 patients with positional vertigo without clinical evidence of positional nystagmus who were treated with a modified canal-repositioning maneuver. Methods Results were compared with the results obtained in the treatment of posterior semicircular cupolo-canalithiasis with typical positional nystagmus with the same repositioning maneuver. Results Treatment of 43 patients with positional vertigo without positional nystagmus resulted in a 60.46% (26/43) complete recovery rate and a 6% (3/43) persistence of disorder rate compared with a 90% complete recovery rate obtained in 90 patients with typical benign positional paroxysmal vertigo (with positional nystagmus). Conclusions What is attempted by this work is to confirm that through clinical evaluation based on history and positioning tests alone, one can obtain acceptable results in treatment of supposed canalithiasis without having detected the pathognomonic nystagmus. [ABSTRACT FROM AUTHOR]

Objectives To evaluate the efficacy of modifications to traditional particle repositioning maneuvers in the treatment of benign paroxysmal positional vertigo. Study Design Prospective trial of 118 patients with cupolocanalithiasis of the posterior canal treated with three different canal-repositioning techniques. Methods Results were compared with the maneuvers employed and the statistical importance of rotating patients by 360° along their longitudinal axis and head shaking on reaching each single position were evaluated. Results Treatment of patients with our maneuver, which, in comparison with traditional repositioning maneuvers, was modified by breaking the procedure up into seven positions and rotating patients by 360° along their longitudinal axis, gives a higher, but not statistically significant, number of treatment successes (84.5%) than the traditional Parnes maneuver (60%) ( P = .154); treatment of a third group of patients with our modified particle repositioning maneuver with the addition of head-shaking on reaching each single position gives a higher (95.6%), statistically significant number of treatment successes than traditional Parnes maneuver ( P = .00011). Conclusions The success rates achieved from modified particle repositioning maneuvers are statistically significant. Onset or persistence of dizziness, which patients frequently complain of after liberatory maneuvers, affects only 5.6% of the patients treated. This low incidence is statistically correlated to head-shaking. [ABSTRACT FROM AUTHOR]

Benign Paroxysmal Positional Vertigo (BPPV) is among the most common vestibular disorders, characterized by brief vertigo spells triggered by head position changes with abrupt onset and rapid decrease. BPPV is ascribed to otoconial matter dislodged from utricular macula and attached to the cupula of the affected semicircular canal (cupulolithiasis) or free-floating within its lumen (canalolithiasis). According to the vestibulo-ocular reflex pathophysiology, each cupular deflection, either exciting or inhibiting the corresponding ampullary afferents, generates the contraction of specific extraocular muscles couples leading to pathognomonic nystagmus. The Upright BPPV Protocol (UBP) is a diagnostic approach to BPPV conducted in the sitting position slowly bending the patient's head along the spatial axes, aiming to move canaliths by gravity within the involved semicircular canal, under continuous nystagmus monitoring by video-Frenzel goggles. UBP starts with the evaluation of pseudo-spontaneous nystagmus in the primary gaze position and continues with the upright Head Pitch Test (uHPT) by forward and backward head bendings along the pitch plane. The uHPT can indicate whether horizontal or vertical semicircular canal is involved. If horizontal canal is suspected, the upright Head Roll Test (uHRT) usually provides the diagnosis of the involved side and arm by tilting the patient's head rightward and leftward along the roll plane. Conversely, canalolithiasis involving the posterior semicircular canal can be diagnosed with the uHPT alone. Nevertheless, if necessary, the diagnostic sensitivity can be increased by head movements along the right anterior – left posterior (RALP) and left anterior – right posterior (LARP) canal planes (uRALP/uLARP test). Following the UBP, most BPPV form can be diagnosed in upright position, allowing clinicians to proceed immediately with proper physical treatment and avoiding unpleasant maneuvers to patients. • BPPV diagnosis should be based on the step-by-step observation of the evoked nystagmus. • The Minimum Stimulus Strategy aims to minimize the patient's discomfort. • The Upright BPPV Protocol is performed in the sitting position through head movements along the spatial planes. • The sensitivity of the head pitch test for horizontal canal-BPPV is increased by the upright head roll test. • The sensitivity of the head pitch test for posterior canal-BPPV is increased by the upright RALP/LARP test. [ABSTRACT FROM AUTHOR]

Introduction Benign paroxysmal positional vertigo (BPPV) is a type of vertigo and its signs are short-time, severe attacks that occur in certain head and body positions. Recent studies have revealed that vitamin D deficiency correlates with BPPV and this is explained by cupulolithiasis and canalithiasis theories. Method In the present study, levels of serum vitamin D in the patients who were diagnosed as BPPV and those in the control group consisting of healthy individuals were investigated. In addition, it was examined whether vitamin D is influential on the rates of BPPV types. In our study, 258 patients who were diagnosed with BPPV after detailed ear-nose-throat and neurology examinations were examined. We compared the control group according to their ages, genders, and levels of vitamin D. In addition, we divided the BPPV group into two sub-groups according to their vitamin D levels (20-30 ng/ml and 20 g/ml lower), and each was compared by calculating vertigo types and ratios. Results The BPPV group included 187 females and 71 males, and their mean age was 43.70 ± 15.44. The control group consisted of 65 females and 35 males, and the mean age of this group was 44.63 ± 15.42. The mean vitamin D levels of the females and males were 18.42 ± 5.07 and 19.82 ± 5.11, respectively, in this study. On the other hand, the mean vitamin D levels of healthy females and males were found to be 30.88 ± 10.74. Conclusion Our study found that the vitamin D levels of the individuals in the BPPV group were statistically significantly lower than those of the individuals who were in the control group. However, it was observed that vitamin D did not affect the rate of vertigo subtypes., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Seyed Resuli et al.)

Benign paroxysmal positional vertigo (BPPV) is a common cause of vertigo. Symptoms from BPPV lead to Emergency Department (ED) visits, and persistence of symptoms, particularly in the elderly, may impact patient disposition. We describe the techniques used in the case of a 72-year-old male with dizziness, who had symptom resolution, and was able to be safely discharged after a Lempert maneuver (barbeque (BBQ) roll) was performed in the ED setting. The patient presented to the ED with left gaze nystagmus, and otherwise normal evaluation results. Physical therapy was consulted, and their initial evaluation indicated right horizontal canalithiasis noted by fatiguing right, geotropic nystagmus, but the patient was unable to tolerate further testing due to vomiting. Antiemetic medications were administered and at his follow-up examination an hour later, a total of three Lempert maneuvers were performed, resulting in total symptom resolution. Successful utilization of the Lempert maneuver to treat BPPV can help to reduce ED length of stay and increase patient satisfaction. Because of this, the Lempert maneuver should be considered a fast, cost-effective, and safe method of alleviating BPPV symptoms., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Hwu et al.)

The diagnosis of benign positional vertigo (BPV) relies on a history of episodic positional vertigo and a distinctive pattern of nystagmus during provocative positional testing. The direction of the induced nystagmus is specific to the affected canal and the velocity profile reflects the underlying mechanism of canalithiasis (free-floating otoconia within the canal duct) or cupulolithiasis (otoconia adherent to the cupula). We review current theories on the pathophysiology of BPV, the clinical history and examination underlying its diagnosis, and recommended repositioning manoeuvres for each of the BPV subtypes. Disorders other than BPV which may present with a similar history and/or positional nystagmus are discussed.

ABSTRACT Objective: To describe an unusual patient reaction to maneuvers used in the treatment of posterior canal benign paroxysmal positional vertigo (PC-BPPV) that we termed the “Tumarkin-like phenomenon”. Methods: At a private practice, 221 outpatients were diagnosed and treated for PC-BPPV. The treatment consisted of performing the Epley or Semont maneuvers. At the end of these maneuvers, when assuming the sitting position, the patients’ reactions were recorded. Results: Thirty-three patients showed a Tumarkin-like phenomenon described by a self-reported sensation of suddenly being thrown to the ground. In the follow-up, this group of patients remained without PC-BPPV symptoms up to at least 72 hours after the maneuvers. Conclusion: The occurrence of a Tumarkin-like phenomenon at the end of Epley and Semont maneuvers for PC-BPPV may be linked with treatment success.

Purpose: Benign paroxysmal positional vertigo (BPPV) involving the horizontal and superior semicircular canals is difficult to study due to variability in diagnosis. We aim to compare disease, treatment, and outcome characteristics between patients with BPPV of non-posterior semicircular canals (NP-BPPV) and BPPV involving the posterior canal only (P-BPPV) using the particle repositioning chair as a diagnostic and therapeutic tool., Methods: Retrospective review of patients diagnosed with and treated for BPPV at a high volume otology institution using the particle repositioning chair., Results: A total of 610 patients with BPPV were identified, 19.0% of whom had NP-BPPV. Patients with NP-BPPV were more likely to have bilateral BPPV (52.6% vs. 27.6%, p < 0.0005) and Meniere's disease (12.1% vs. 5.9%, p = 0.02) and were more likely to have caloric weakness (40.3% vs. 24.3%, p = 0.01). Patients with NP-BPPV required more treatments for BPPV (average 3.4 vs. 2.4, p = 0.01) but did not have a significantly different rate of resolution, rate of recurrence, or time to resolution or recurrence than patients with posterior canal BPPV., Conclusions: Comparison of NP-BPPV and P-BPPV is presented with reliable diagnosis by the particle repositioning chair. NP-BPPV affects 19% of patients with BPPV, and these patients are more likely to have bilateral BPPV and to require more treatment visits but have similar outcomes to those with P-BPPV. NP-BPPV is common and should be part of the differential diagnosis for patients presenting with positional vertigo., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objective: To explore the clinical value of rolling test（HRT）, bow and lean test（BLT） and subjective vertigo sensation(SVS) for affected side localization of patients with horizontal semicircular canal benign paroxysmal positional vertigo（HSC-BPPV）. Method: One hundred and thirty-eight patients（94 HSC-Can and 44 HSC-Cup）with HSC-BPPV were enrolled. Patients were tested with HRT and then were asked about SVS, followed by BLT. According to the results of HRT, SVS and BLT, HSC-Can and HSC-Cup were repositioned by Barbecue method and modified Kim method respectively. The detection rate of the affected side of HRT, BLT, SVS and the curative effect were analyzed. Result: In 94 HSC-Can patients and 44 HSC-Cup patients,BN and / or LN were induced by BLT to be 81.91% and 84.09% respectively. HRT induced bilateral asymmetric nystagmus 90.43%, 88.64%, SVS told vertigo symptoms worse side 60.64%,63.64%. There was no significant difference in the detection rate of HRT and BLT( P >0.05)，but have significant difference with SVS( P <0.05). Excluding four patients in whom the comparison among HRT,BLT,SVS were inconclusive，we compared the curative effect of first treatment in 92 HSC-Can patients and 42 HSC-Cup patients. The curative effect of HRT positive only were 66.67% and 60.00% respectively , BLT positive only were 71.43% and 66.67% respectively , HRT and BLT both positive with ipsilateral affected side were 70.37% and 65.50% respectively , HRT and BLT both positive with contralateral affected side were 37.50% and 30.00% respectively. The curative effect of HRT positive only and BLT positive only had no significant difference with that of HRT and BLT both positive with ipsilateral affected side , but they both had significant difference with that of HRT and BLT both positive with contralateral affected side . Conclusion: HRT is the most effective method for detecting affected side of HSC-BPPV, but BLT and SVS also have auxiliary diagnostic value as HSC-BPPV localization method., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Benign paroxysmal positional vertigo (BPPV) is the most common peripheral vestibular disorder. BPPV is easily diagnosed by positioning tests and effectively treated by repositioning maneuvers. The authors focus on the treatment of BPPV, when different canals are affected, including canalo- and cupulolithiasias. Complications of BPPV and surgery of cases, resistant to conservative treatment, are also discussed.