Evaluation of Semicircular Canal Function in Relapsing Polychondritis Patients With Dizziness and Sensorineural Hearing Loss Using Video Head Impulse Test

OBJECTIVE

To evaluate semicircular canal function using video head impulse test (vHIT) in relapsing polychondritis (RP) patients presenting with dizziness and sensorineural hearing loss.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

Three patients with RP underwent vHIT and hearing tests.

INTERVENTION

Diagnostic.

MAIN OUTCOME MEASURES

The gain in vestibulo-ocular reflex (VOR) and the presence of catch-up saccade were examined, and the correlation between semicircular canal dysfunction and hearing loss was investigated.

RESULTS

Of the six ears, five exhibited semicircular canal dysfunction. Among these, one ear showed dysfunction in two semicircular canals, while the remaining four ears demonstrated dysfunction in all three semicircular canals. Sensorineural hearing loss, ranging from moderate to profound, was detected by pure-tone audiometry in all six ears. Furthermore, a significant correlation was observed between VOR gain in the horizontal semicircular canal (HSC) and hearing level.

CONCLUSIONS

This study demonstrated semicircular canal dysfunction in RP patients presenting with dizziness and hearing loss using vHIT. Moreover, a significant correlation was found between HSC dysfunction and the severity of hearing loss. While inner ear involvement is a key clinical symptom included in the diagnostic criteria for RP, there have been few reports evaluating vestibular dysfunction, and this is the first report on the evaluation of several cases using vHIT. Accurate assessment of vestibular function by vHIT may facilitate early diagnosis and intervention in RP, potentially improving patient outcomes.

Vestibular Disorders Limited to the Vertical Semicircular Canals

Introduction  The advent of the video head impulse test (vHIT) enables the study of each one of the six semicircular canals. In the present study, certain patients present disorders related only to the vertical semicircular canals, and they were carefully evaluated. Objective  To investigate vestibular disorders limited to the vertical semicircular canals. Methods  In total, 9,891 patients were submitted to the vHIT in our clinic; 26 (2.63%) of them, 11 men and 15 women, showed reduced vestibulo-ocular reflex (VOR) limited to the vertical canals. All of these patients had vestibular symptoms. Results  These patients presented different disorders of the vestibular system, and ten of them presented vestibular neuritis. Conclusion  Now, vestibular disorders limited the vertical canals can be evaluated through the vHIT. These disorders, however, may relate do different labyrinthine diseases.

Association of audiovestibular findings with fluid-attenuated inversion recovery magnetic resonance imaging in patients with vestibular schwannoma

BACKGROUND

Vestibular schwannoma (VS) is a benign tumor of the vestibular nerve. Flair-attenuated inversion recovery (FLAIR) of magnetic resonance imaging (MRI) images are sensitive in detecting high protein contents of fluids.

OBJECTIVES

To investigate the association between signal intensity (SI) on FLAIR images and audiovestibular findings in patients with VS.

METHODS

Medical records of twenty-five patients with VS were retrospectively analyzed.

RESULTS

Larger tumors were associated with increased FLAIR SI of the cochlea, vestibule, and semicircular canal (SCC) on the affected side compared to those of the unaffected side. Pure-tone audiometry (PTA), and speech audiometry were associated with the SI of the affected cochlea. There was no significant correlation between the SI of the vestibule and vestibular evoked myogenic potential, SI of the SCC, and caloric test or video head impulse test results.

CONCLUSION

Our study suggests that tumor size was significantly associated with high SI on FLAIR imaging, and audiological findings were associated with the SI of the affected cochlea. Further studies with larger cohorts are required to confirm the association between vestibular function and FLAIR imaging in VS.

Evaluation of Semicircular Canal Function Using Video Head Impulse Test in Patients With Peripheral Vestibular Disorders Without Nystagmus

Objectives This study aims to evaluate semicircular canal function using video head impulse test (vHIT) in patients with peripheral vestibular disorders without nystagmus. Methods Patients who underwent vHIT were enrolled in this study, and the proportion of abnormal findings on vHIT in patients without nystagmus was investigated. In addition, the results of vestibular testing were investigated in cases in which both vHIT and caloric testing were performed in patients without nystagmus. Results Forty-six patients (23.4%) of 197 patients who had no abnormal findings on the nystagmus tests, including the gaze nystagmus test, positional nystagmus test, and positioning nystagmus test, showed dysfunction in at least one semicircular canal on vHIT. The most frequent diagnosis was vestibular schwannoma (14/46, 30.4%), and cases with bilateral vestibular dysfunction were also included (12/46, 26.1%). A disorganized pattern of catch-up saccade was observed more frequently in patients with subjective symptoms of dizziness/vertigo compared to those without subjective symptoms. Although the sensitivity of vHIT was low compared to caloric testing, vHIT could detect isolated vertical canal dysfunction not detected by caloric testing. Conclusions vHIT is considered to be a useful test for patients without nystagmus, as vHIT could detect abnormalities in approximately one-quarter of patients without nystagmus. vHIT is considered to be one of the first tests to be performed following nystagmus testing, including the gaze nystagmus test, the positional nystagmus test, and the positioning nystagmus test. On the other hand, there are some cases in which vHIT shows no abnormality while caloric testing shows canal paresis. It is necessary to perform vHIT, bearing in mind that there are abnormalities that cannot be detected by vHIT alone.

Pre- and post-operative semicircular canal function evaluated by video head impulse test in patients with vestibular schwannoma

OBJECTIVES

To evaluate pre- and post-operative semicircular canal function in patients with vestibular schwannoma (VS) by the video Head Impulse Test (vHIT).

METHODS

Nineteen patients with VS who underwent surgery were enrolled in this study. The gain in vestibulo-ocular reflex (VOR) and the degree of scatter in catch-up saccades were examined pre- and post-operatively for the semicircular canals in VS patients.

RESULTS

Ten of 19 cases (52.6 %) with VS were defined as demonstrating both superior vestibular nerve (SVN) and inferior vestibular nerve (IVN) impairment from the results of pre-operative vHIT. Hearing level and subjective vestibular symptoms showed significant correlations with pre-operative semicircular canal function. Compared to pre-operative vHIT results, VOR gains within 1 month after surgery were significantly reduced in all three canals; however, significant differences had disappeared in the anterior and posterior semicircular canals at 6 months after surgery. Cases of unknown origin had a significantly greater reduction in posterior semicircular canal function after surgery compared with those with disease of IVN origin.

CONCLUSIONS

As vHIT could evaluate pre-operative vestibular nerve impairment, post-operative VOR gain reduction and the degree of vestibular compensation, semicircular canal function evaluated by vHIT provides a good deal of useful information regarding VS patients undergoing surgery compared to caloric testing, and vHIT should be performed pre- and post-operatively for patients with VS.

Vestibular Assessment with the vHIT and Skull Vibration-Induced Nystagmus Test in Patients with Nonprogressive Vestibular Schwannoma

Background: Our primary objective was to monitor nonprogressive unilateral vestibular schwannomas (VSs) to assess the efficiency of rapid bedside examinations, such as the video head impulse test (vHIT) and skull vibration-induced nystagmus test (SVINT), in identifying vestibular damage. Methods: An observational study was conducted from March 2021 to March 2022 on all adult patients (>18 years old) with a confirmed nonprogressive VS (no active treatment). The SVINT (using a 100 Hz vibrator with two (SVINT2) or three (SVINT3) stimulation locations) and vHIT (for the six semicircular canals (SCCs)) were performed on all patients. The asymmetry of function between the vestibules was considered significant when the gain asymmetry was greater than 0.1. Rapid and repeatable assessment of VSs using two- and three-stimulation SVINT plus vHIT was performed to quantify intervestibular asymmetry. Results: SVINT3 and SVINT2 triggered VIN in 40% (24/60) and 65% (39/60) of patients, respectively. There was significant asymmetry in the vestibulo-ocular reflex (VOR), as shown by a VS-side gain < healthy-side gain in 58% (35/60) of the patients. Among the patients with significant gain asymmetry between the two vestibules according to the vHIT (VS-side gain < healthy-side gain), the proportion of patients expressing vestibular symptomatology was significantly greater than that of patients without any symptoms [67% (29/43) vs. 35% (6/17), respectively; p = 0.047]. Conclusions: The SVINT2 can be combined with the vHIT to form an interesting screening tool for revealing vestibular asymmetry. This work revealed the superiority of mastoid stimulation over vertex stimulation for SVINT in patients with unilateral vestibular loss.

Posterior Semicircular Canal Dehiscence with Vestibulo-Ocular Reflex Reduction for the Affected Canal at the Video-Head Impulse Test: Considerations to Pathomechanisms

Posterior semicircular canal dehiscence (PSCD) has been demonstrated to result in a third mobile window mechanism (TMWM) in the inner ear similar to superior semicircular canal dehiscence (SSCD). Typical clinical and instrumental features of TMWM, including low-frequency conductive hearing loss (CHL), autophony, pulsatile tinnitus, sound/pressure-induced vertigo and enhanced vestibular-evoked myogenic potentials, have been widely described in cases with PSCD. Nevertheless, video-head impulse test (vHIT) results have been poorly investigated. Here, we present six patients with PSCD presenting with a clinical scenario consistent with a TMWM and an impaired vestibulo-ocular reflex (VOR) for the affected canal on vHIT. In two cases, an additional dehiscence between the facial nerve and the horizontal semicircular canal (HSC) was detected, leading to a concurrent VOR impairment for the HSC. While in SSCD, a VOR gain reduction could be ascribed to a spontaneous "auto-plugging" process due to a dural prolapse into the canal, the same pathomechanism is difficult to conceive in PSCD due to a different anatomical position, making a dural herniation less likely. Alternative putative pathomechanisms are discussed, including an endolymphatic flow dissipation during head impulses as already hypothesized in SSCD. The association of symptoms/signs consistent with TMWM and a reduced VOR gain for the posterior canal might address the diagnosis toward PSCD.

Quantitative Evaluations of Vestibular Function in Patients With Petrous Apex Cholesterol Granulomas Treated With an Endoscopic Transsphenoidal Approach: A Report of Two Cases

OBJECTIVE

We report two cases of petrous apex cholesterol granuloma (PACG) treated with an endoscopic transsphenoidal approach. Vestibular functions of the two patients were evaluated quantitatively by video Head Impulse Test (vHIT) and/or vestibular evoked myogenic potentials (VEMPs).

PATIENTS

Two patients with PACG who experienced episodes of dizziness are presented.

INTERVENTION

An endoscopic transsphenoidal approach to PACG.

MAIN OUTCOME MEASURE

The preoperative and postoperative vestibular functions as evaluated by vHIT and VEMP.

RESULTS

Two cases of PACG were treated by a transsphenoidal approach. The internal auditory canal was compressed by the PACG in both cases. The patients both experienced episodes of dizziness before surgery and preoperative vestibular testing including vHIT and VEMP indicated dysfunction of vestibular nerves. After surgery, their symptoms were completely resolved, and the vestibular testing results were improved.

CONCLUSIONS

This article is noteworthy for being the first to publish quantitative vestibular function testing for patients with PACG with vestibular dysfunction. PACG may show various symptoms, with dizziness being one of the most common symptoms. In cases in which the internal auditory canal is compressed by the PACG, vestibular functions should be evaluated by vHIT and VEMP. In the present cases, dizziness was found to be resolved by surgery to release the compression on internal auditory canal. Based on the present cases, the transsphenoidal approach is considered to be both safe and effective.

Audiovestibular Consequences of Congenital Cytomegalovirus Infection: Greater Vulnerability of the Vestibular Part of the Inner Ear

OBJECTIVES

To investigate the impact of congenital cytomegalovirus infection on cochlear and vestibular function.

DESIGN

This retrospective study conducted between March 2014 and March 2020 included children with confirmed congenital cytomegalovirus infection who underwent a complete audio-vestibular evaluation. It included a bithermal caloric test, a video head impulse test and a cervical vestibular evoked myogenic potential associated with a complete hearing assessment.

RESULTS

The cohort of 130 children included in the study had a median age of 21 months (interquartile range: 12 to 37 months). Eighty-three children (64%) showed an inner ear impairment (both cochlear and vestibular). The vestibular part of the inner ear was significantly more frequently impaired than the cochlear part (ρ = 0.003). Sixty-two children (48%) showed confirmed hearing impairment. The severity of hearing loss was variable, with a high proportion of profound hearing loss (30/62, 48%), which was often bilateral (47/62, 76%). The vestibular assessment showed a canal function disorder in 67 children (88%) and an otolith function disorder in 63 children (83%; ρ = 0.36). The video head impulse test was significantly less altered (64%) compared with the bithermal caloric test (80%; ρ = 0.02) and the cervical vestibular evoked myogenic potential (83%; ρ = 0.009). Only seven out of 83 children (8%) showed hearing loss without vestibular dysfunction, of which only one had a normal hearing screening test at birth. For the children who passed the hearing screening test at birth and presented an inner ear impairment [n = 36, median age: 16 (11 to 34) months], vestibular disorders were later found in 35 children (97%) and 17 of them (47%) developed hearing loss secondarily. This underlines the importance of assessing both vestibular and auditory parts of the inner ear. When comparing the agreement of cochlear and vestibular impairment, the severity and the laterality of the impairment were low [Cohen's kappa 0.31 (0.22 to 0.40) and 0.43 (0.32 to 0.55), respectively].

CONCLUSION

In our study, we demonstrated that although both cochlear and vestibular parts of the inner ear can be impaired by congenital cytomegalovirus infection, the vestibular part seems more often impaired compared with the cochlear part. This underlines the importance of vestibular evaluation in the follow-up of cytomegalovirus-infected children associated with hearing assessment.

Evaluation of Semicircular Canal Function by Video Head Impulse Test in Patients With Labyrinthine Fistula Due to Cholesteatoma

OBJECTIVES

To evaluate semicircular canal function in patients with labyrinthine fistula (LF) due to cholesteatoma by the video Head Impulse Test (vHIT).

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

Ten patients with LF due to cholesteatoma and six without LF underwent vestibular examination.

INTERVENTION

Diagnostic.

MAIN OUTCOME MEASURES

The gain in vestibulo-ocular reflex (VOR) and the presence of catch-up saccade were examined for the semicircular canals in patients with LF.

RESULTS

Seven of 10 cases (70.0%) in the fistula group were judged to have semicircular canal dysfunction based on preoperative evaluation. VOR gains in the patients with LF were significantly lower than those in the patients without LF. VOR gain decreased significantly in accordance with the severity of the LF. The postoperative VOR gain more than 6 months after surgery was significantly improved compared with the preoperative VOR gain.

CONCLUSIONS

The vHIT is thought to be the most suitable method for evaluating semicircular canal function in patients with LF due to cholesteatoma as it is not influenced by middle ear pathology and can evaluate the function of the vertical canals. The vHIT could predict whether a LF is present or not before surgery, and the vHIT is essential for surgery for patients with LF.

Discrepancies in the caloric testing and video Head Impulse Test results in a case with bilateral lateral semicircular canal malformations

Lateral semicircular canal (LSCC) malformations represent one of the most common types of inner ear malformation. As many cases of LSCC malformations are asymptomatic, detailed vestibular functions in such cases remain unclear. We present a case with bilateral LSCC malformations for whom the function of each vestibular organ was evaluated by caloric testing, video Head Impulse Test (vHIT) and vestibular evoked myogenic potentials (VEMP). Caloric testing showed canal paresis of the left side, whereas vHIT showed bilateral normal semicircular canal function. The results of VEMP indicated left saccular dysfunction. Discrepancies in caloric testing and vHIT results were observed and these discrepancies are thought to be due to endolymphatic hydrops rather than vestibular hypofunction, similar to that in Meniere disease.

Analysis of semicircular canal function as evaluated by video Head Impulse Test in patients with vestibular schwannoma

OBJECTIVE

The aim of the present study was to investigate the factors influencing semicircular canal function as evaluated by video Head Impulse Test (vHIT) in patients with vestibular schwannoma.

METHODS

Twenty-four patients with untreated vestibular schwannoma underwent vHIT examination. The correlations between semicircular canal function and factors including age, tumor size, disease duration and hearing loss were evaluated.

RESULTS

The functions of all three semicircular canals on the affected side evaluated by vHIT were significantly lower than those on the unaffected side. Although there were no significant correlations between semicircular canal function and age, tumor size or disease duration, a negative significant correlation between vestibulo-ocular reflex (VOR) gain as evaluated by vHIT and hearing loss was observed.

CONCLUSIONS

From the results of the relationship between hearing loss and VOR gain, the damage to the audio and vestibular systems in patients with VS may be correlated. As it has been suggested that tumor size was not a significant factor in the VOR gain evaluated by vHIT, multifactorial causes rather than the simple compression of the vestibular nerves alone may be related to the dysfunction of the semicircular canals in patients with vestibular schwannoma.

Usefulness of the Video Head Impulse Test for the Evaluation of Vestibular Function in Patients With Otitis Media With Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

OBJECTIVES

To investigate usefulness of the video Head Impulse Test (vHIT) as a method for evaluating semicircular canal function in patients with otitis media with antineutrophil cytoplasmic antibody-associated vasculitis (OMAAV).

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

Fourteen patients with OMAAV underwent vestibular examination.

MAIN OUTCOME MEASURES

The gain in vestibulo-ocular reflex (VOR) and the presence of catch-up saccade were examined for each semicircular canal.

RESULTS

Seven (50.0%) of the 14 patients felt subjective symptoms of disequilibrium. Dysfunction in at least one semicircular canal was detected in all ears of the OMAAV patients evaluated by vHIT. Dysfunction in posterior semicircular canal was detected more frequently than that in the anterior or horizontal canal. There were no significant correlations between the gain in VOR and hearing loss.

CONCLUSIONS

vHIT is thought to be the most suitable method for evaluating semicircular canal function in patients with OMAAV as vHIT is not influenced by middle ear pathology and was able to evaluate vertical canal function including the posterior canal.

Volume quantification of endolymphatic hydrops in patients with vestibular schwannoma

•

Origin of vestibular symptoms in patients with VS is unknown.

•

Intratympanic gadolinium-enhanced MRI could confirm labyrinthine lesion in VS.

•

The volume percentage of the endolymphatic space was more accurate than the area percentage for assessing vestibular EH.

•

Vestibular symptoms in patients with VS may originate from peripheral lesions.

Objective

The origin of vestibular symptoms in patients with vestibular schwannoma (VS) is uncertain. We used intratympanic gadolinium-enhanced magnetic resonance imaging (MRI) to confirm the labyrinthine lesions in patients with VS and to explore the features of endolymphatic hydrops (EH) in these patients.

Methods

In total, 66 patients diagnosed with unilateral VS were enrolled in this study and underwent intratympanic gadolinium-enhanced MRI. The borders of the vestibule and endolymph were mapped on the axial MRI images, and the area and volume of vestibule and endolymph were automatically calculated using Osirix software, and the area and volume percentage of vestibular endolymph were obtained.

Results

The area and volume percentages of vestibular endolymph on the affected side were significantly larger than those on the healthy side (both p < 0.001). Using Kendall's W test, we found that the area and volume percentages of vestibular endolymph on the affected side were consistent (p < 0.001), but the consistency was moderate (k = 0.574). The healthy side was also consistent (p < 0.001), and the degree of consistency was moderate (k = 0.444). We used 19.1% as the cut-off point to distinguish the presence or absence of vestibular EH; that is, the volume percentage of vestibular endolymph that was more than 19.1% were defined as the subgroup with hydrops, while the subgroup without hydrops included patients with a baseline level below 19.1%. No volume classification for vestibular EH was proposed. Based on this standard, 11/66 (16.7%) of the patients with VS in this study had vestibular EH. Conclusions.

The volume percentage of the vestibular endolymph was more accurate than the area percentage for assessing vestibular EH. Using 19.1% as the cut-off point to distinguish the presence or absence of vestibular EH, we found that 16.7% of patients with VS had varying degrees of vestibular EH. We believe that the vestibular symptoms in patients with VS may originate from the peripheral lesions.

Vibration-induced nystagmus and head impulse test screening for vestibular schwannoma

LEVEL OF EVIDENCE

II-2.

BACKGROUND

Vestibular schwannomas are benign tumors of the eight cranial nerve that may cause asymmetric sensorineural hearing loss (ASHL) and vestibular dysfunction.

OBJECTIVE

The aim of this study was to assess the role of the video head impulse test (vHIT) and vibration-induced nystagmus (VIN) test in diagnosing vestibular schwannoma in a population of patients with Asymmetric sensorineural hearing loss.

MATERIAL AND METHODS

For this prospective case-control study, 23 consecutive patients with ASHL and normal magnetic resonance were enrolled in the control group, and 33 consecutive patients with ASHL and vestibular schwannoma were enrolled in the case group. Gold standard was magnetic resonance imaging. Audiometry, vHIT, and VIN tests were performed for each patient. Significance of VIN and vHIT testing was determined by evaluation of their sensitivity, specificity, and correlation with vestibular function tests.

RESULTS

Regarding the vHIT, sensitivity and specificity were 45.5% and 82.6%, respectively, for horizontal canal gain, 60.6% and 87.6%, respectively, for posterior canal gain, and 45.5% and 78.3%, respectively, when analyzing superior canal gains. Regarding the VIN test, the sensitivity and specificity were 81.8% and 73.9%, respectively, when based on the presence of a VIN with any mastoid stimulation.

CONCLUSIONS

Our results suggest that using the VIN test may be an efficient approach to screen for vestibular schwannoma in patients with asymmetric sensorineural hearing loss.

SIGNIFICANCE

Our results suggest that using the VIN test may be an efficient approach to screen for vestibular schwannoma in patients with ASHL.