Semicircular Canal Research Articles

Radiological relations of sigmoid sinus with oto-neuro-surgical landmarks with its surgical risk-stratification indicating classification.

Detailed pre-operative HRCT scan-based measurement of the distance between surgical landmarks with lateral or sigmoid sinus (SS) and classification of its relations with surgical landmarks. Observational Study. Tertiary care center. Patient volunteers above 18 years of age undergoing scans for various reasons. Axial Sections of HRCT of 260 temporal bones obtained from patient volunteers were studied with the help of RadiAnt DICOM Viewer (version 2023.1). Closest distance of the SS from the posterior wall of the external auditory canal wall (CW), the vertical portion of the facial nerve (VPFN), the short process of incus (SPI), lateral (LC), and posterior semi-circular canal (PC), was measured. The SS relation with the mastoid was classified as type 1-4 depending upon the shortest distance of the sinus from the posterior canal wall millimeters. The mean distance of the SS from surgical landmarks was 14.6 ± 2.7mm for SPI, 11.1 ± 3.1 for CW, 11.4 ± 2.9 for VPFN, 10.1 ± 2.8 for PC, and 11.9 ± 2.7 LC. All measured distances were significantly more on the left side (p < 0.05, Z test), except the difference in distance from LC. The greatest range of variation (5.2 to 21.8mm) was seen in the distance between SS and VPFN. The most common type of relationship between SS and CW was type 3, present in 64% of subjects, while the least common group was type 1, with nearly 1% of subjects. The assessment of distances and relations of various surgical landmarks with SS, with the proposed novel classification based on SS-CW distance, can be essential for preoperative planning and risk mitigation.

Different audiometric findings with different symptoms for diagnosing superior semicircular canal dehiscence symptoms: a retrospective study of 12 cases

BackgroundDue to the patients with no symptoms for dehiscence but having audiological different findings who came to clinic, this study aims to evaluate the audiological characteristics of 12 cases diagnosed with superior semicircular canal dehiscence and to compare the findings with the literature.MethodsWe evaluated a case-series of 12 cases aged 11–59 years with a pre-diagnosis of semicircular canal dehiscence (SSCD) by clinical history and audiological evaluation between 2019 and 2022 and a final diagnosis by high-resolution computed tomography. Audiological evaluation includes air-bone conduction and speech audiometry, tympanometry, and acoustic reflex test.ResultsUnilateral dehiscence was observed in 6 cases, and bilateral dehiscence was observed in the other 6. Considering types of hearing loss, we observed 5 normal hearing, 1 mixed type, 2 conductive type, and 4 sensorineural type. Also, numerous clinical characteristics were observed: vestibular complaints (9/12), chronic imbalance (9/12), Tullio phenomenon (6/12), Hennebert sign (6/12), and tinnitus (5/12). Patients with symptoms no audiological findings and patients with audiological findings no symptoms were seen with dehiscence diagnosis.ConclusionVarious symptoms and findings were observed in patients with semicircular canal dehiscence. While patients with no symptoms for diagnosing dehiscence are presented, audiological findings with low-frequency hearing loss and air–bone gap can be landmark. In addition, patients with SSCD symptoms, even if they do not have audiometric findings, should be further evaluated with radiological evaluation.

A Comparison of Vestibular Function in Young Adult Musicians and Nonmusician Peers.

The majority of college-level musicians exceed the daily recommended noise dose level during instrumental practices and performances, although less than one third report wearing hearing protection while playing their instruments. Although the hazardous effects of music on the auditory system have been established, even in young adult musicians still early in their musical careers, the effects of music on the vestibular system are still unclear. The purpose of the present study was to examine vestibular/balance differences between young adult musicians and nonmusicians to determine the effects of music exposure on the vestibular system. Young adult participants aged 18-27 years without any history of hearing loss, vestibular/balance disorder, otologic disorder, or nervous system disorder were included in this study. Participants were divided into musician (n = 19) and nonmusician (n = 18) groups. Vestibular function was assessed and compared via the cervical vestibular evoked myogenic potential (cVEMP), ocular vestibular evoked myogenic potential (oVEMP), video head impulse test (vHIT), and modified clinical test of sensory interaction in balance (mCTSIB). Musicians were found to produce significantly more saccades in the left horizontal semicircular canal during vHIT assessment compared to nonmusicians. Group differences were not found in the cVEMP, oVEMP, or mCTSIB. This study shows the effects of music exposure on the vestibular system in young adult musicians who show early-onset, subclinical findings on the vHIT that could develop into abnormal results on vestibular assessments if hearing protection use is not increased.

Outcomes of Radiologist Recommendations for Temporal Bone CT to Assess Superior Semicircular Canal Dehiscence on Temporal Bone MRI.

Superior semicircular canal dehiscence can be detected on temporal bone MR images. Radiologists often recommend confirmation with temporal bone CT due to reported lower MRI positive predictive value. The value of these recommendations is unclear given that CT overestimates dehiscence due to volume averaging and that only a small proportion of patients with dehiscence on CT suffer from dehiscence syndrome. We thus evaluated final diagnoses and outcomes in patients who adhered to the recommended additional CT. This retrospective cohort observational study, performed at a multi-institution healthcare system, included consecutive temporal bone MRI reports 6/1/2021-5/31/2022 with a recommendation for additional temporal bone CT. We recorded: whether CT was performed, dehiscence present on CT, symptoms, final diagnosis, treatment decisions, and outcomes. Actionability elements (complete containing imaging modality, time frame, and rationale; unambiguous; unconditional; without multiplicity; and without alternate language) of the recommendations were extracted from a prior data set. Descriptive statistics were performed. A binomial generalized linear model was used to test the correlation of ambiguous recommendation language with recommendation adherence. Summarize actual data. 5109 temporal bone MRI examinations were performed and interpreted by 34 radiologists. 187/5109 reports (3.7%) included a recommendation for additional temporal bone CT including 101/5109 (2.0%) specifically for suspected superior semicircular canal dehiscence. While 22% (22/101) of these recommended examinations were performed, only 32% of these (7/22) confirmed dehiscence. Ultimately, only 1 patient was diagnosed with dehiscence syndrome and was managed conservatively. No recommendations for additional imaging (0/101) met actionable criteria and 76.2% (77/101) were ambiguous. Ambiguous recommendations had 0.54 lower, but not statistically significant, odds of being performed (95% CI: 0.19-1.6, p=0.25). Radiologist recommendations for temporal bone CT in the setting of questionable superior semicircular canal dehiscence findings on MRI appear to have negligible clinical value and thus it is likely most appropriate to report possible SSCD in the MRI report impression without recommending further imaging. SSCD= superior semicircular canal dehiscence.

Skull vibration induced nystagmus, velocity storage and self-stability

In this paper we give an introduction to the area, followed by brief reviews of the neural response to sound and vibration, and then the velocity storage integrator, before putting forward our hypothesis about the neural input to the velocity storage integrator. Finally we discuss some of the implications of our hypothesis. There are two pathways conveying neural information from the vestibular periphery (the semicircular canals and the otoliths) to central neural mechanisms—a direct and an indirect pathway. Within the indirect pathway there is a unique neural mechanism called the velocity storage integrator (VSI) which is part of a neural network generating prolonged nystagmus, afternystagmus and the sensation of self-motion and its converse self-stability. It is our hypothesis that only neural input from primary afferent neurons with irregular resting discharge projects in the direct pathway, whereas the primary afferent input in the indirect pathway consists of neurons with regular resting discharge. The basis for this hypothesis is that vibration is a selective stimulus for vestibular neurons with irregular resting discharge. 100 Hz mastoid vibration, while capable of generating nystagmus (skull vibration induced nystagmus SVIN), is ineffective in generating afternystagmus (in the condition of an encased labyrinth) which is a marker of the action of the VSI, leading to the conclusion that irregular afferents bypass the indirect pathway and the VSI. In order to present this hypothesis we review the evidence that irregular neurons are selectively activated by sound and vibration, whereas regular neurons are not so activated. There are close similarities between the temporal characteristics of the irregular afferent neural response to vibration and the temporal characteristics of SVIN. SVIN is a simple clinical indicator of whether a patient has an imbalance between the two vestibular labyrinths and our hypothesis ties SVIN to irregular primary vestibular neurons.

World-wide survey on the treatment of peripheral vestibular disorders

ObjectiveThe aim of this world-wide survey was to evaluate the currently applied treatment options for the six most frequent peripheral vestibular disorders: benign paroxysmal positional vertigo (BPPV), acute unilateral vestibulopathy (AUVP)/vestibular neuritis, Menière’s disease (MD), bilateral vestibulopathy (BVP), vestibular paroxysmia (VP) and superior canal dehiscence syndrome (SCDS).BackgroundFor the therapy of vestibular disorders, there are four treatment options: vestibular physical therapy (canalith repositioning maneuvers or balance training), pharmacotherapy, surgery, and psychotherapy. Since there are very few state-of-the-art RCTs, the treatment of vestibular disorders is so far not standardized and various methods are applied with heterogeneous efficacy.Design/methodsA web-based standardized survey questionnaire on the treatment of the six most frequent peripheral vestibular disorders was used to collect data.Results234 replies from five continents, 47 countries, 162 cities and 188 centers were received: (% from all 234 replies; multiple answers possible): BPPV: posterior canal BPPV: 71% Epley, 40% Semont, and 12% others. Horizontal canal BPPV canalolithiasis: 58% Lempert (roll-over) maneuver, 33% Gufoni, 7% prolonged rest, and 9% others. Horizontal canal BPPV cupulolithiasis: 35% Gufoni, 27% Lempert (roll-over) maneuver, 9% Zuma, and 7% head shaking: AUVP: 79% pharmacotherapy, namely 47% glucocorticoids, 39% antiemetics, and 24% betahistine; 67% vestibular physical therapy. MD: 85% pharmacotherapy, namely 65% betahistine, 21% diuretics, 20% steroids, 16% antiemetics, 14% gentamicin; 37% surgery. VP: 65% pharmacotherapy, namely 57% anticonvulsants; 7% surgery. BVP: 77% vestibular physical therapy. SCDS: 50% surgery, namely 38.8% canal plugging, 23.3% capping and 15.5% resurfacing.ConclusionIn this world-wide survey with 234 replies from 188 centers, widely heterogeneous applied treatment options were reported for the six most frequent peripheral vestibular disorders. This study shows in particular that certain drugs are often used despite low or very low evidence. Namely in AUVP, MD and VP well-designed controlled trials with clinically meaningful endpoints are needed.

Pöschl Reformations Created from High-Resolution Noncontrast Enhanced CT Head Exams Can Be Used to Detect and Classify Superior Semicircular Canal Abnormalities.

To compare the diagnostic capability of Pöschl reformations created from temporal bone CT (TBCT) and high-resolution noncontrast CT head exams (HR-NECTH) to detect and classify superior semicircular canal (SSC) abnormalities. Retrospective case review. Tertiary referral center. Individuals with normal and abnormal SSC who received TBCT and HR-NECTH. Pöschl reformations of each patient's temporal bones (TB) were created using TBCT and HR-NECTH. Screenshots displaying the SSC were randomized into an interpretation test sent to neuroradiologists who interpreted the SSC as normal/abnormal and classified abnormalities as thinning (SST)/dehiscence (SSD). Analysis of responses to interpretation test, interrater reliability, and sensitivity, specificity, and positive/negative predictive values of Pöschl reformations from TBCT and HR-NECTH. Fourteen patients were enrolled, 28 TB were reviewed. Sixteen TB demonstrated SST/SDD and 12 were normal as per gold standard TBCT. Interpretation test displaying screenshots of the SSC, in a randomized, blinded fashion, was completed by four neuroradiologists. Analysis of TBCT and HR-NECTH Pöschl reformation interpretations yielded no statistically significant difference in proportion of true/false-positive/negative responses (χ2 = 3.37, p = 0.83), similar and substantial interrater reliability (k = 0.78 vs. 0.73, respectively), and similar sensitivity, specificity, and positive/negative predictive values (0.86, 1, 1, 0.84 vs. 0.78, 0.96, 0.96, 0.77, respectively). Neuroradiologists also correctly classified SST/SSD on TBCT and HR-NECTH Pöschl reformations at a rate of 70.9% vs. 78.0%, respectively. Pöschl reformations created from HR-NECTH demonstrated similar diagnostic capability as those created from TBCT to detect and classify SSC abnormalities.

Underwater endoscopic ear surgery vs. microscopic open approach for repair of semicircular canal fistulae secondary to middle ear cholesteatoma: a systematic review and meta-analysis

Underwater endoscopic ear surgery vs. microscopic open approach for repair of semicircular canal fistulae secondary to middle ear cholesteatoma: a systematic review and meta-analysis

The Prevalence of Congenital Cervical Stenosis Differs based on Race.

Congenital cervical stenosis (CCS) is a rare condition involving a narrowed spinal canal due to developmental anomalies. CCS heightens the risk of neurologic deficits and acute spinal cord injury post-trauma, influencing return-to-play decisions for contact athletes. Additionally, CCS patients are prone to cervical myelopathy as degenerative changes progress with age. Limited evidence-based literature exists addressing the epidemiology of CCS, including the effects of race. To investigate the anatomical differences and prevalence of CCS as it pertains to race and ethnicity. Single center retrospective cross-sectional study. A total of 343 patients with cervicalgia between the years of 1999-2023. Radiographic measurements of anatomical parameters were collected and CCS was defined as a sagittal canal diameter (SCD) of less than 10 mm at 2 or more vertebral levels (C3-7) at the pedicle. We screened 5395 cervical MRIs from a single institution. Exclusion criteria included patients under 18 and over 50 years, prior cervical spine surgery, congenital fusions, spinal malignancy, or active smoking history. For each patient, axial measurements were taken at each level, including coronal vertebral body length, anteroposterior vertebral body length, pedicle width, pedicle length, laminar length, anteroposterior lateral mass length, posterior canal distance, apex-to-vertebral body, lamina-disc angle (LDA), lamina-pedicle angle, and anteroposterior spinal cord diameter. CCS prevalence varied significantly among ethnic groups; Black (39.3%), Asian (33.6%), and Hispanic (22%) patients demonstrated significantly higher CCS rates than White patients (7.5%) [x2 (3, N=343) = 30.04, p <0.05)]. Blacks and Asians showed consistently smaller SCDs at all pedicle levels compared to Whites, who had the largest SCDs overall (p<0.001). Average SCDs were 11.4 mm (White), 10.4 mm (Black), 10.5 mm (Asian), and 11 mm (Hispanic). Additionally, LDAs were larger in Asians, Blacks, and Hispanics compared to Whites, leading to a significantly decreased cross-sectional canal area (p<0.001). Our study indicates a statistically significant correlation between race/ethnicity and CCS prevalence. Black and Asian patients had the highest CCS rates, smallest SCDs, and largest LDAs. These anatomical differences may predispose these subjects to the development of cervical myelopathy compared to those with normal spinal canal diameters. Increased knowledge base of the epidemiology of this condition may lead to personalized clinical management and possibly early intervention to prevent spinal cord injuries in these patients.

Feasibility and safety of repositioning maneuvers for posterior semicircular canal BPPV (benign paroxysmal positional vertigo) in elderly over 80 years of age.

Balance problems in the elderly are a major social concern, primarily due to the risk of falls. One of the reasons of fast worsening of stability and therefore falling is represented by acute BPPV. Treatment through repositioning maneuvers could significantly reduce the risk of further falls of the patients treated with. The physical ability of older individuals to be treated with maneuvers is a topic of debate due to possible joint stiffness and less compliance with movements. There are few previous studies focusing on the practicality and effectiveness of physical therapy for BPPV in people over 80 years. We conducted a retrospective study collecting data on 517 patients to assess the feasibility, effectiveness, safety and the number of therapeutic maneuvers necessary to get therapeutic success when treating individuals over 80 years compared to those aged between 18 and 64. We found no difference in terms of number of maneuvers needed to get therapeutic success between the two groups. As for the therapeutic maneuver no difference in success and feasibility of execution was found between Semont and Epley maneuvers which proved equally effective in the two groups. Our data are not inconsistent with the hypothesis that repositioning maneuvers for posterior canal BPPV are feasible and demonstrated a good efficacy in all elderly people. This could encourage the diagnosis and treatment of BPPV also for the purpose of reducing the risk of falls in the elderly.

Impact of Vibrations and Rapid Decelerations on SemontPLUS Maneuver Efficacy: An In Vitro Study.

We aimed to investigate the effect of adding "rapid decelerations" and "vibrations" during a SemontPLUS maneuver on the dynamics of the inner ear and the success rate of canalolithiasis repositioning. We used a previously described upscaled (5×) in vitro model of the posterior semicircular canal of the inner ear to analyze the trajectory of a single and clumped surrogate otolith particle (metallic sphere) during a SemontPLUS maneuver (-60 degrees below earth horizontal) on a repositioning chair (TRV). We compared the angular displacement of these particles with and without the application of "vibrations" or "rapid decelerations" using TRV. We recorded the success rates of the SemontPLUS maneuver for each condition. After the first step of the SemontPLUS, the application of "vibrations" increased the angular displacement of single particles from 119.9 to 125.9 degrees and clumps from 106.7 to 122.8 degrees. Clumps traveled shorter distances than single particles. "Rapid decelerations" also increased the angular displacement from 119.9 to 123.4 degrees and from 106.7 to 111.7 degrees for singles and clumps, respectively. "Vibrations" and "rapid decelerations" applied on the in vitro model resulted in enhanced repositioning success rates to 60 and 73%, respectively. Adding "rapid decelerations" or "vibrations" to the SemontPLUS maneuver increased otolith particle displacement and improved the repositioning success rates in an in vitro model. However, the effect size of these additional modalities on angular displacement is small, and their use in clinics to improve repositioning in the SemontPLUS would have to be supported by further clinical trials.

Clinical spectrum of positional downbeat nystagmus: a diagnostic approach.

Positional downbeat nystagmus (pDBN) is a common finding in dizzy patients, with etiologies ranging from benign paroxysmal positional vertigo (BPPV) to central vestibular lesions. Although peripheral pDBN often presents with distinct clinical features that differentiate it from BPPV, diagnosing its etiology can be challenging. A thorough clinical evaluation, including the physical characteristics of the nystagmus, response to positional maneuvers, and neurological findings, is often sufficient to diagnose conditions that provoke pDBN such as anterior canal BPPV, atypical posterior canal BPPV, and central causes. However, when the diagnosis remains uncertain, a brain MRI focusing on the posterior fossa is required. In human lesion models, the vestibulocerebellum (nodulus and uvula) is commonly implicated in pDBN. Central causes of positional vertigo include vascular events, tumors, immune mediated, toxicity, and demyelinating diseases. Ultimately, a significant number of cases will remain without a clear etiology despite extensive workup. Clinicians should be vigilant for signs suggesting central vestibular dysfunction at follow-up in cases of apparently refractory BPPV. The aim of this work is to provide a comprehensive overview of pDBN and offer a logical approach to its assessment, along with recommendations for future research directions.

Thirty years with cervical vestibular myogenic potentials: a critical review on its origin.

Myogenic potentials generated by acoustic stimulation of the vestibular system have been reported since 1964. This examination became better known as cervical vestibular evoked myogenic potentials (cVEMPs) and gained increasing clinical application since the nineties. Since its discovery, the saccule has been conceived as the most likely vestibular end-organ driving these myogenic potentials of the neck. As findings from both animal and human studies for a long time uniformly provided evidence supporting this theory, cVEMP assessment has become synonymous with evaluation of saccular and inferior vestibular nerve function. This review of the basic evidence supporting this conclusion, questions if cVEMP may be considered as being predominantly or even exclusively driven by the activation of any single vestibular end-organ. We conclude that the results of this review show that contributions from the crista ampullaris of all three ipsilateral semicircular canals, as well as the ipsilateral utricle cannot be ruled out in clinically conducted cVEMP assessments.

Vestibular Function in Patients With Vestibular Neuritis Experiencing Prodromal Dizziness.

It is unknown whether prodromal dizziness (PD) before an attack of vestibular neuritis (VN) has an association with peripheral vestibular lesions. The purpose of this study was to investigate whether the severity of vestibular dysfunction has an association with the presence of PD. We reviewed the medical records of 88 consecutive unilateral VN patients with unilateral canal paresis in caloric testing. Caloric test, cervical vestibular evoked myogenic potential test to air-conducted sound (ACS cVEMP), ocular vestibular evoked myogenic potential test to bone-conducted vibration (BCV oVEMP) and video head impulse test (vHIT) were used as vestibular function tests. Binomial logistic regression analyses were performed to see whether the subjects' age, sex, disease duration or the presence of PD is associated with the presence of vestibular dysfunction. Seventeen (19%) experienced an episode of PD. There was no significant association between the presence of PD and abnormality in ACS cVEMPs, BCV oVEMPs, vHIT for the posterior semicircular canal (SCC) or vHIT for the lateral SCC. The presence of PD had a significant positive association with abnormality in vHIT for the anterior SCC (ASCC) (p = 0.0248). The presence of PD in VN may be associated with the peripheral vestibular lesion.

An Exploratory Study of Peripheral Vestibular System in Users of Personal Listening Devices.

The widespread use of mobile phones and personal listening devices (PLDs) poses potential health risks, particularly noise-induced hearing loss. Among younger generations, high-volume PLD use is associated with auditory and vestibular system changes. Clinical vestibular testing, including vestibular-evoked myogenic potentials (VEMP) and the video head impulse test (vHIT), may reveal peripheral vestibular impacts from prolonged PLD exposure at volumes over 60%. This study examines VEMP and vHIT results in individuals with normal hearing who have had extended high-volume PLD exposure. Subjects and. A cross-sectional comparative study was conducted on individuals aged 15-24 years. All the participants had normal pure tone thresholds with "A" type tympanogram, present acoustic reflexes, and history of PLD usage. Participants were divided into groups according to PLD exposure of <1 year (group A), 1.1-2 years (group B), 2.1-3 years (group C), and 3.1-4 years (group D). The output sound pressure level (dB SPL) near the tympanic membrane was measured. Furthermore, cervical VEMP, ocular VEMP, and vHIT were assessed. The VEMP and vHIT findings were statistically analyzed and compared across groups. The peak-to-peak amplitudes of VEMP showed a statistically significant difference between groups A and D. Potential subclinical damage to the otolith organs can be associated with increased PLD exposure. No damage to the semi-circular canals was observed as the participants used lower dBA values by the PLDs.

Postural crisis in patients undergoing canalith repositioning procedures for posterior canal benign paroxysmal positional vertigo: A systematic review and meta-analysis.

The Epley or Semont maneuver is performed for posterior canal benign paroxysmal positional vertigo (PC-BPPV). The postural crisis indicates the phenomenon that the patient experiences severe dizziness, is unable to maintain the sitting posture, and suddenly falls backward or sideways on the examination table when returning to the sitting position, which is the final step of the canalith repositioning procedure (CRP). The postural crisis increases the risk of falls during CRP. This meta-analysis aimed to determine the incidence of postural crisis among patients who underwent CRP for PC-BPPV. Literature searches were conducted on PubMed, Embase, Cochrane Library, Web of Science, and Google Scholar. The random-effects model was utilized based on the results of the heterogeneity using the Tau2 test and I2 statistic. We included 5 nonrandomized studies that reported the total number of cases of CRP for PC-BPPV and postural crisis. In each study, postural crisis occurred in 4.0% to 14.9% of the subjects. Of a total of 1177 cases, the incidence of postural crisis in all CRP cases was 10% (95% confidence interval = 6%-15%). BPPV is the most common among peripheral vestibular diseases, usually occurring in the posterior semicircular canal. Therefore, 10% of cases with CRP for PC-BPPV is significant. When performing CRP for PC-BPPV, considering that the postural crisis related to increasing the risk of falls may occur, preparations for the phenomenon should be made in advance.

Comparative effectiveness of the exact versus estimated angle of head position in the Epley maneuver: a randomized controlled trial.

Introduction The Epley maneuver is the recommended treatment for benign paroxysmal positional vertigo of the posterior semicircular canal (PC-BPPV). Traditionally, the angle of the patient's head in each position during the Epley maneuver is not monitored and subjectively estimated by physicians. As a result, deviations of head angles from the standard may affect the treatment result. This study aimed to compare the outcome of the Epley maneuver between the group of exact head angles and the group of subjectively estimated angles (traditional Epley maneuver). Methods A single-blind randomized controlled trial was conducted at the Department of Otolaryngology, Chiang Mai University Hospital. PC-BPPV patients were attached with the head angle measuring device and randomized into 2 groups: Group I - the exact angle group, physicians performed the Epley maneuver with accurate head angle in each step; and Group II - the estimated angle group, physicians performed the Epley maneuver by estimating the head angle (traditional Epley maneuver). The treatment outcomes were measured at 1 week in the aspects of negative Dix Hallpike results and severity of dizziness. Results Thirty-one PC-BPPV patients were recruited and randomized into Group I (15 participants) and Group II (16 participants). Both groups showed clinical improvement. Although significant deviations of head angles were observed in group II, there was no significant difference in outcomes between the two groups in terms of negative Dix Hallpike and severity of dizziness at the 1-week follow-up. Conclusion Although significant variations of head angles were observed during the traditional Epley maneuver by experienced physicians, these deviations were slight (less than 15°) and did not significantly affect the successful treatment outcome at 1 week, in terms of negative Dix Hallpike and severity of dizziness, when compared to the group with accurate head angle during the Epley maneuver.

The role of audiological features and horizontal semicircular canal function at various frequencies in vestibular migraine and Menière’s disease

Background Vestibular migraine (VM) and Menière’s disease (MD) have numerous overlapping symptoms. Distinguishing the two common recurrent vestibulopathies was challenging. Objectives To assess the characteristics of hearing loss and the horizontal semicircular canal function in VM and MD. Materials and methods Various frequency horizontal semicircular canal function tests, including caloric test, video head impulse test (vHIT), and rotatory chair test, as well as multifrequency audiological test with pure-tone average (PTA), were carried out. Results The hearing threshold of all frequencies in VM is lower than that of MD (p < .05). The phase shift at 0.01 Hz, 0.02 Hz, 0.04 Hz, 0.08 Hz and 0.64 Hz was significantly different in VM and MD patients. The gain at 0.01 Hz differed between VM and MD (p < .05); the time constant (RTc) in VM patients was longer than that of MD patients (p < .05). The incidence of caloric test abnormality was 40% in VM patients and 68.3% in MD patients. The abnormal rate of horizontal semicircular canal vHIT was 3.2% in VM and 5.8% in the MD, and the rates of overt/cover saccades were 9.7% and 17.6%, respectively. Conclusions The degree and type of hearing loss were conducive to distinguishing between VM and MD, and the rotatory chair test was a necessary supplement.

Factors Associated With Balance and Fear of Falling in Patients With Benign Paroxysmal Positional Vertigo: A Controlled Cross-Sectional Study.

The aim of this study is to evaluate the factors influencing balance and fear of falling (FOF) in patients with benign paroxysmal positional vertigo (BPPV). A controlled cross-sectional study. Single center study. A total of 31 patients with BPPV and 30 controls were included in this cross-sectional study. The handgrip strength (HGS) was measured using the Jamar hydraulic hand dynamometer. Ultrasound measurements of muscle thickness (MT) of the biceps brachii, medial head of gastrocnemius, and lateral head of gastrocnemius were recorded. MT/body mass index was calculated. FOF was assessed using the Falls Efficacy Scale (FES). The Berg Balance Scale (BBS) was used to assess the participants' balance. The timed up and go test (TUG) was used to evaluate physical function. The video head impulse test (VHIT) was used to evaluate the semicircular canals. The FES scores and TUG duration were higher and the BBS scores were lower in patients with BPPV compared with the control group (p < 0.001). Univariate analysis showed that dominant HGS (B = -1.380, p = 0.012), BMI (B = 2.391, p = 0.011), and female gender (B = 18.369, p = 0.036) were associated factors for the FES in patients with BPPV. Age (B = -0.239, p < 0.001), dominant HGS (B = 0.441, p < 0.001), BMI (B = -0.503, p = 0.032) and R ASC (B = -12.601, p = 0.006) were associated variables for the BBS. Age was an associated factor for the TUG (B = 0.158, p = 0.017). Lower HGS, higher BMI and female gender were associated factors for greater FOF in patients with BPPV. Clinicians should be aware of risk factors and educate patients regarding balance and FOF.

Post-operative vestibular function outcomes evaluated by video Head Impulse Test in patients with non-vestibular schwannoma cerebellopontine angle tumors.

To evaluate post-operative semicircular canal function in patients with non-vestibular schwannoma (VS) cerebellopontine angle (CPA) tumors by video Head Impulse Test (vHIT). Fourteen patients with non-VS CPA tumors who underwent surgery. The gain in vestibulo-ocular reflex (VOR) was examined pre- and post-operatively for the semicircular canals in patients with non-VS CPA tumors. Ten of 14 patients showed semicircular canal dysfunction in one or more of the semicircular canals pre-operatively and VOR gain was significantly correlated with hearing function. Two patients showed improvement in one or more semicircular canals at 1 month after surgery compared to the pre-operative results. Significant improvements in VOR gain were observed when comparing VOR gain at 1 month and 6 months after surgery. Detailed evaluation of semicircular canal function was achieved by using vHIT in patients with non-VS CPA tumors. The good prognosis for vestibular function as evaluated by vHIT post-operatively was confirmed in patients with non-VS CPA tumors when compared to those in patients with VS. As improvement may occur post-operatively, surgical approaches that preserve the vestibular nerves and semicircular canals should be chosen for patients with non-VS CPA tumors, regardless of preoperative vestibular function. Even if vestibular function deteriorates immediately after surgery, it may improve over time if the nerve is preserved.