Impact of endolymphatic hydrops on the function of the horizontal canal during caloric stimulation in Ménière's disease.

PURPOSE: When a dizzy patient with episodic vertigo has an abnormal caloric and a normal video head impulse test (vHIT), this caloric-vHIT dissociation provides vital information for a diagnosis of Ménière's disease (MD). Endolymphatic hydrops (EH), a histological marker of MD, is hypothesized to be involved in the caloric-vHIT dissociation in MD through hydropic duct distension of the horizontal semicircular canal (SC). This study was designed to determine the impact of EH on the function of horizontal SC during caloric stimulation. METHODS: Caloric test and vHIT were used to evaluate the function of horizontal SC every six months, annual magnetic resonance imaging (MRI) was used to evaluate the degree of EH size in the vestibule, and monthly vertigo and hearing evaluation was done for 12 months. EH shrinkage was defined as the size change of vestibular EH from significant to none. RESULTS: Among 133 MD patients evaluated for eligibility, 67 patients with caloric-vHIT dissociation entered the study. Fifteen participants had EH shrinkage (G-I), while 52 participants had no remarkable EH change (G-II). Average values (IQR) of the maximum slow phase velocity in G-I and G-II were 29.6 (13.0-34.0) and 25.9 (17.3-31.3), respectively, at baseline, 26.1 (9.0-38.0) and 23.6 (18.0-28.3) at 12 months. Two-factor repeated-measures ANOVA showed no significant differences between the groups (P = 0.486). The values of vestibulo-ocular reflex gain of the horizontal SC in G-I and G-II remained above 0.8 during the study period. CONCLUSIONS: EH detected by MRI shows limited correlation with caloric stimulation results.

Vestibular function assessment in Idiopathic sudden sensorineural hearing loss: a prospective study.

PURPOSE: Idiopathic sudden sensorineural hearing loss (ISSHL) can cause acute damage not only to the auditory function, but also to the vestibular function in addition to damage to the hearing function. The aim of this study was to perform vestibular assessment using caloric test and video head impulse test in patients with idiopathic sudden sensorineural hearing loss. In addition, to evaluate the relationship of dizziness with vestibular tests and post-treatment responses of vestibular tests. METHODS: This is an observational, longitudinal and prospective study, including patients diagnosed with idiopathic sudden sensorineural hearing. Patients were divided into two groups according to the presence of vestibular complaints at presentation: Group 1: Patients with vestibular complaints, Group 2: Patients without vestibular complaints. All subjects underwent pure tone audiometry (PTA) testing, cold caloric test and video head impulse test (vHIT) during their admission and on the 10th day, 3rd month, and 1st year of their follow-up outpatient clinic controls. A unilateral weakness (UW) in the caloric test response was quantified according to the Jongkees formula. RESULTS: A positive and significant relationship was found between the degree of hearing loss according to the ASHA criteria pre-treatment and the level of improvement created according to Siegel criteria at the 10th day, 3rd month, 1st year after treatment (respectively p = 0.001, p = 0.001, p < 0.001). When both short-term and long-term results were evaluated after treatment, a positive improvement in the degree of hearing loss was observed. A statistically significant difference was observed between Groups 1 and 2 when the pre-treatment, at 10 days, 3 months and 1 year after treatment the caloric test UW value was compared (respectively p = 0.020, p = 0.004, p = 0.004, p = 0.004). A statistically significant difference was observed between Groups 1 and 2 when the pre-treatment, at 10 days, 3 months and 1 year after treatment vHIT lateral canal VOR value was compared (respectively p = 0.000, p = 0.001, p = 0.000, p = 0.004). When both short-term and long-term results were evaluated after treatment, a positive improvement was observed in both caloric test results and lateral vHIT VOR values. Pre-treatment, post-treatment 10th day, 3rd month, 1st year vHIT anterior and posterior canal VOR values were found to be VOR˃0.8 in all patients. No difference was observed in anterior and posterior canal VOR values. CONCLUSION: Vertigo in patients with ISSHL "as objectively confirmed through caloric testing and vHIT" can be considered a sign of severe cochlear damage. Our study demonstrated a significantly increased risk of vestibular affect in patients with ISSHL, especially in the presence of vertigo. Thus, we conclude that the focus in ISSHL should not only be on the cochlea but also on the vestibular system.

A novel methodology to demonstrate vestibulo-ocular reflex using caloric stimulation in undergraduate physiology laboratory.

The study aims to develop a novel methodology to demonstrate the vestibulo-ocular reflex (VOR) and nystagmus by caloric stimulation in an undergraduate medical physiology laboratory. The experimental setup involved two sets of electrodes: one set positioned laterally to both eyes, and another set positioned vertically over either the right or left eye. The caloric method is used to stimulate ears, which involves irrigation of warm (44°C) and cold (30°C) water into the ears while maintaining a temperature difference of approximately ±7°C from the body temperature. The changes in chorioretinal potential were calibrated to angular displacement by a two-point calibration method, and angular velocity was derived after taking the first-time derivative. The results obtained from the digital data acquisition system were compared to the traditional instrument used in our Otorhinolaryngology Department [Interacoustics Videonystagmography (VNG) System for hospitals, medical grade] for the normal subject's data. No significant differences in angular velocity were noted (P > 0.05). The cold stimuli elicit a more pronounced VOR compared to the warm stimuli. It has been consistently observed that the onset of nystagmus occurs approximately 20 s after irrigation, reaching its peak intensity between 45 and 90 s, and gradually diminishing until it ceases after approximately 200 s. Our developed methodology enables the recording and quantification of nystagmus using easily accessible equipment. This study serves the goal of visualizing the physiological process of VOR and thereby fulfills the goal of an effective teaching tool for demonstrating to undergraduate medical students.NEW & NOTEWORTHY We developed a novel methodology to demonstrate and visualize the most common and important physiological phenomenon like the vestibulo-ocular reflex as a teaching module for undergraduate students.

Changes of video head impulse test before and after translabyrinthectomy in patients with acoustic neuroma. / å¬ç¥žç»ç˜¤æ‚£è€ ç»è¿·è·¯åˆ‡é™¤æœ¯å‰åŽè§†é¢‘å¤´è„‰å†²è¯•éªŒçš„å˜åŒ–.

OBJECTIVES: Acoustic neuroma (AN) is a benign tumor that usually affects a patient's hearing and balance function. For the screening and diagnosis of AN, the traditional approach mainly relies on audiological examination and magnetic resonance imaging (MRI), often ignoring the importance of vestibular function assessment in the affected area. As an emerging method of vestibular function detection, video head impulse test (vHIT) has been widely used in clinic, but research on its use in AN diagnosis is relatively limited. This study aims to explore the value of vHIT in the diagnosis of AN, vestibular dysfunction assessment, and postoperative compensation establishment in unilateral AN patients undergoing unilateral AN resection through labyrinthine approach. METHODS: This retrospective study was conducted on 27 AN patients who underwent unilateral AN resection via labyrinthine approach from October 2020 to March 2022 in the Department of Otolaryngology-Head and Neck Surgery, the Second Xiangya Hospital, Central South University. vHIT was performed 1 week before surgery to assess vestibular function, pure tone audiometry (PTA) was used to assess hearing level, and ear MRI was used to assess tumor size. Follow-up vHIT was conducted at 1 week, 1 month, 6 months, and 1 year post-surgery. The correlation of vHIT with hearing and tumor size was analyzed. RESULTS: Preoperative vHIT showed that the posterior semicircular canal on the affected side was the most common semicircular canal with reduced vestibulo-ocular reflex (VOR) gain. There was a correlation between the VOR gain of vHIT on the affected side and the hearing level (r=-0.47, P<0.05) or tumor size (r=-0.54, P<0.01). The results of vHIT on the affected side showed that the hearing level and mean VOR gain of the anterior semicircular canal increased slightly with time, and the amplitude and saccade percentage of the dominant saccades of the 3 semicircular canals increased, while the latency time decreased, with the most obvious changes occurring 1 week post-surgery. CONCLUSIONS: vHIT can effectively monitor the changes of vestibular function in AN patients before and after surgery and has application value in assisting the diagnosis of vestibular dysfunction in AN patients.

Long-term follow-up of patients with vestibular neuritis by caloric testing and directional preponderance calculation.

OBJECTIVES: This study focuses on the diagnostic precision of caloric testing in detecting vestibular neuritis (VN). MATERIALS AND METHODS: In this study, 99 patients (36 men, 63 women, mean age: 44.63 years [Formula: see text] 12.08 SD) with superior VN were involved, and 157 participants with a normal functioning vestibular system were also investigated. All patients underwent a complete neurotological examination, including the caloric test with electronystagmography registration. The canal paresis (CP) and directional preponderance (DP) values were analysed. RESULTS: A VN on the right side was diagnosed in 31.3% and on the left side in 68.7%. When the CP parameters between the control and VN patients were contrasted, a statistically significant difference was observed (p < 0.00001*, Mann-Whitney U test), indicating higher values in the latter group. The prediction of VN based on the CP value was successful in 71%, and statistical analysis indicated a significant result [p < 0.0001*; OR: 5.730 (95% CI 3.301-9.948)]. The DP values were also significantly higher in the VN group (p < 0.00001*). The prediction of VN according to the DP value was successful in 69.8%. A significant result was also observed in this case [p < 0.001*; OR: 4.162 (95% CI 2.653-8.017)]. When both CP and DP were considered, a predictive value of 84.8% with a significant outcome [p < 0.0001*; OR: 82.7 (95% CI 28.4-241.03)] was detected. CONCLUSIONS: Including the CP and DP parameters of the caloric test, VN could be detected in around 85%. Therefore, the caloric helps diagnose the disorder, but both parameters must be considered.

Systematic review of the diagnostic value of hydrops MRI in relation to audiovestibular function tests (electrocochleography, cervical vestibular evoked myogenic potential and caloric test).

The objective of this systematic review is to compare the diagnostic value of endolymphatic hydrops (EH) magnetic resonance imaging (MRI) with audiovestibular function tests, including electro cochleography (ECochG), cervical vestibular evoked myogenic potential (cVEMP) and caloric tests for the diagnosis of definite Meniere's disease (DMD). An electronic search was performed in the PubMed, Embase and Cochrane databases in August 2022. Original studies which reported the efficacy of gadolinium MRI for diagnosis of DMD were compared with ECochG, cVEMP and caloric tests from 2007 to 2022 published in English. Two reviewers extracted the methodology and results of MRI and functional tests, assessing them independently. A modified version of the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) was used for the assessment of the quality and the risk of bias of each study. The proportion of DMD cases diagnosed by MRI hydrops vs corresponding functional tests were calculated and the relationship between MRI and functional tests were evaluated using the Cohen's Kappa test. Concerning the MRI, the proportion diagnostic of DMD was 0.67 by cochlear EH and 0.80-0.82 by vestibular EH. Regarding the functional test, the propotiojn diagnostic of DMD was 0.48 by ECochG, 0.76 by cVEMP and 0.65 by caloric test. The findings of this systematic review were that the vestibular EH on imaging most effectively assisted in diagnosing DMD. Among the functional tests, cVEMP was the second most effective test. The agreement between imaging and cVEMP was moderate (0.44), indicating a gap between the patients identified by the imaging and functional tests based on the relatively small number of patients.

Comparison between caloric and video-head impulse tests in Ménière's disease and vestibular neuritis.

OBJECTIVE: To compare the diagnostic accuracies of air caloric testing with electronystagmography and the vHIT (video-head impulse test). DESIGN: Prospective, controlled study. STUDY SAMPLE: MD (Ménière's disease), 26; vestibular neuritis, 27; control, 56. RESULTS: In MD, CP (canal paresis) was pathological in 88.5%, the GA (gain asymmetry) on vHIT was pathological in 65.3%, and the gain was abnormal in only one patient. The GA and CP, were significantly higher in the MD group than in the control group, indicating hypofunction of the horizontal canals in MD, whereas a hyperfunction may also occur. No correlation was observed between the results of the two tests for evaluating MD, suggesting that pathological outcomes of one test do not guarantee abnormalities on the other test. For vestibular neuritis, significantly higher CP (96.3%), GA (81.5%), and gain (51.9%) values were detected. A correlation was identified between the two tests for vestibular neuritis, indicating a similar diagnostic efficiency. The higher percentage of pathological GA versus pathological gain values indicates that the asymmetry may be more informative. CONCLUSIONS: The vHIT showed a higher specificity, whereas the caloric test a higher sensitivity. No correlation between the two methods was observed; therefore, the tests appear to provide complementary information.

Functional and Molecular Markers for Hearing Loss and Vertigo Attacks in Meniere's Disease.

Meniere's disease (MD) is one of the most complicated diseases in the otologic clinic. The complexity of MD is partially due to the multifactorial etiological mechanisms and the heterogenous symptoms, including episodic vertigo, hearing loss, aural fullness and tinnitus. As a result, the diagnosis of MD and differentiating MD from other diseases with similar symptoms, such as vestibular migraine (VM), is challenging. In addition, it is difficult to predict the progression of hearing loss and the frequency of vertigo attacks. Detailed studies have revealed that functional markers, such as pure tone audiometry (PTA), electrocochleography (ECochG), vestibular evoked myogenic potential (VEMP), caloric test, video head impulse test (vHIT) and magnetic resonance imaging (MRI) could help to evaluate MD with different hearing levels and frequency of vertigo attacks. Investigations of molecular markers such as autoimmunity, inflammation, protein signatures, vasopressin and circadian clock genes in MD are still underway. This review will summarize these functional and molecular markers, address how these markers are associated with hearing loss and vertigo attacks in MD, and analyze the results of the markers between MD and VM.

Preoperative vestibular evoked myogenic potentials (VEMPs), caloric test, and pure tone audiometry to identify the vestibular nerve branch of schwannoma origin: preliminary results in a series of 26 cases.

Vestibular schwannoma (VS) is a benign tumor which develops in the internal auditory canal and the cerebellopontine angle, potentially diminishing hearing or balance. Most VS tumors arise from one of two vestibular branches: the superior or inferior vestibular nerve. Determining the specific nerve of origin could improve patient management in terms of preoperative counseling, treatment selection, and surgical decision-making and planning. The aim of this study was to introduce a preoperative testing protocol with high accuracy to determine the nerve branch of origin. The nerve of origin was predicted on the basis of preoperative vestibular evoked myogenic potentials (VEMPs), caloric stimulation test, and pure tone audiometry on 26 recipients. The acquired data were entered into a statistic scoring system developed to allocate the tumor origin. Finally, the nerve of origin was definitively determined intraoperatively. Receiver operating characteristic (ROC) curves analysis of preoperative testing data showed the possibility of predicting the branch of origin. In particular, ROC curve of combined VEMPs absence, nystagmus detectable at caloric stimulation, and PTA < 75 dB HL allowed to obtain high accuracy for inferior vestibular nerve implant of the tumor (area under the curve-AUC = 0.8788, p = 0.012). In 24 of 26 cases, the preoperatively predicted tumor origin was the same as the origin determined during surgery. Preoperative audiological and vestibular evaluation can predict the vestibular tumor branch of origin with high accuracy. Despite the necessity of larger prospective cohort studies, these findings may change preoperative approach, possible functional aspects, and counseling with the patients.

Post headshake nystagmus: further correlation with other vestibular test results.

BACKGROUND: It is generally accepted that headshake nystagmus (HSN) is generated from an asymmetrical peripheral vestibular input and a correlation exists between HSN and canal paresis. There have been limited reports, however, how HSN correlates with the more recently introduced tests of vestibular function. AIMS/OBJECTIVES: To evaluate the correlation between HSN and unilateral weakness on caloric testing, high-frequency vestibulo-ocular reflex (VOR) function on video head impulse testing (VHIT) and otolith function determined by vestibular evoked myogenic potentials (VEMPs). METHODS: A retrospective study of all patients who underwent complete vestibular function testing at our tertiary referral center from 2016 to 2019 was performed. Demographic data, clinical diagnosis (where available), the results of video-nystagmography, vHIT, and VEMPs were evaluated. RESULTS: Of the 1499 patients in the study period, 101 (6.7%) had HSN. Vestibular test abnormalities were more common in patients with HSN. The sensitivity of HSN for underlying pathology was low in comparison with vestibular testing. However, HSN demonstrated a high specificity. CONCLUSIONS AND SIGNIFICANCE: HSN generation is likely more complex than caloric-induced nystagmus, probably due to additional variables within the vestibular system. HSN may provide clinicians with additional information concerning high-frequency VOR function involving lateral semicircular and otolith dysfunction.

Evaluation of vestibular function following endolymphatic sac surgery.

PURPOSE: To evaluate objective vestibular function after endolymphatic sac surgery (ELSS) for Menière's disease (MD), using comparative vestibular function tests: videonystagmography (VNG), vestibular evoked myogenic potentials (VEMP) and video head-impulse test (VHIT) METHODS: Patients with definite MD using the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) of 1995 criteria modified in 2015 and treated with ELSS (sac decompression or sac opening) were included. The primary outcome was the preservation of vestibular function, comparing pre- and postoperative vestibular function tests: VNG, VEMP, VHIT. Secondary outcomes were control of episodes of vertigo, hearing outcome using AAO-HNS criteria, and QoL using the Menière's disease outcome questionnaire. RESULTS: 73 patients were included in the study. We found a significant preservation of vestibular function as measured by VNG and VHIT. There was no statistical difference in the presence or absence of cervical and ocular (P13/N23 and N1/P1) waves on VEMP pre- and postoperatively. 67% of patients had good control of episodes of vertigo post-operatively, with significantly better results in the sac opening group (75%). There was no significant change in hearing postoperatively, and QoL scores were significantly improved after surgery (p < 0.0001). CONCLUSION: Endolymphatic sac surgery (ELSS) is a conservative surgical treatment, which does not negatively impact vestibular function. It was associated with improved control of episodes of vertigo, preservation of hearing, and a clear improvement in QoL scores. Despite its pathophysiology not being fully understood, it remains a first-line procedure preserving vestibular function, for MD refractory to medical management.

Effectiveness of hearing protection apparatus in preventing noise induced vestibular loss.

Hearing protection apparatus (HPAs) are frequently used to prevent the detrimental effect of noise on the hearing system. However, it is not known exactly whether wearing HPAs in workers protects the vestibular system. This study aims to investigate the effectiveness of wearing HPAs in preventing vestibular loss caused by noise. Eighty-one workers exposed to chronic noise were divided into three groups according to their HPAs wearing status. Pure-tone audiometry test was used to evaluate the hearing. Caloric test and visual analogue scale were used to evaluate their vestibular systems. The pure-tone average of the workers who constantly wore HPAs was better than that of the other groups (p< 0.05). There was no difference between the groups in the vestibular tests (p > 0.05). This study demonstrated that HPAs do not protect the vestibular system but protect the hearing system in the inner ear from the harmful effects of noise.

[Dissociation of the results of caloric and video head impulse tests as a marker of Meniere's disease]. / Dissotsiatsiya kaloricheskogo i videoimpul'snogo testov u patsientov s bolezn'yu Men'era.

The study of vestibular function in patients with Meniere's disease (MD) is an urgent task, since it influences the choice of treatment tactic. We evaluated the results of caloric and video head impulse (vHIT) tests in 76 patients who met the clinical criteria for significant Meniere's disease (AAO-HNS modified by the Barany Society, 2015). Dissociation of the results of caloric and vHIT tests is observed in the majority (74%) of patients with MD: at normal gain, according to vHIT data, hypofunction of peripheral vestibular structures is recorded according to the caloric test (KASL 47 ± 7.8%). In patients with MD, vestibular dysfunction is observed mainly at low frequencies (0.003 Hz), therefore vHIT, which allows assessing horizontal semicircular canal function at high frequencies (3-5 Hz), is not an optimal study for assessing the degree of vestibular dysfunction in patients with MD.

Comparison of the results of caloric and video head impulse tests in patients with Meniere's disease and vestibular migraine.

PURPOSE: To compare the results of video head impulse test (vHIT) and caloric testing (CT) in patients with vestibular migraine (VM) and Ménière's disease (MD) and to investigate the relationship between these two tests. METHODS: Patients with definite unilateral MD and VM were included in the study. All patients underwent both vHIT and CT. The vestibulo-ocular reflex (VOR) gains of lateral semicircular canals and saccadic waves in vHIT and the canal paresis factor for the CT were examined. RESULTS: CT was found abnormal in 39 (66.1%) patients with MD and in 17 (34%) patients with VM, while abnormal gain of the lateral canal was obtained in 23 MD (39%) patients and 9 (18%) VM patients. In all, 11.9% of patients with an abnormal vHIT had a normal CT, whereas 33.9% of those with an abnormal CT had a normal vHIT. CONCLUSION: Loss of VOR detected by caloric testing is more common and severe in MD than VM. Although vHIT is useful and can give complementary information, vestibular testing with the caloric test still seems more sensitive for detecting hVOR pathology.

Evaluation of audiovestibular system in psoriasis patients without joint involvement.

Inner ear involvement may occur in systemic autoimmune diseases. Although there are studies evaluating hearing in psoriasis patients, its effect on the balance system is not clear. The aim of the present study was to evaluate the audiovestibular system in psoriasis patients without joint involvement. In this prospective study, the audiovestibular system of 32 psoriasis patients without joint involvement and 35 healthy volunteers were evaluated. The severity of the disease was determined by the psoriasis area severity index (PASI). There was no significant difference between the groups in terms of hearing test results, while the abnormal caloric test response was significantly higher in the psoriatic patients. PASI scores of psoriasis patients with abnormal caloric test results were higher than those with normal caloric test response. In psoriasis patients without joint involvement, the hearing was not affected, but the vestibular system was. The severity of the disease was associated with vestibular involvement. Particularly in patients with severe psoriasis, it must be considered that the vestibular system might be affected, and vestibular evaluations should be performed.

The semicircular canal function tests contribute to identifying unilateral idiopathic sudden sensorineural hearing loss with vertigo.

BACKGROUND: Few studies focused on the prognosis of unilateral idiopathic sudden sensorineural hearing loss (UISSNHL) with vertigo. OBJECTIVES: To describe how the semicircular canal (SCC) function tests may prove helpful in the diagnosis of UISSNHL with vertigo. MATERIAL AND METHODS: 59 UISSNHL patients underwent audiometry, caloric test and video head impulse test (vHIT). The correlation between hearing loss and SCC dysfunction was analyzed. RESULTS: The results showed significant differences of hearing loss grades (p = 0.004) and hearing loss configurations (p = 0.009) between UISSNHL patients with and without vertigo. In vHIT, the gains of horizontal canal (HC) and posterior canal (PC) were more frequently impaired compared with that of anterior canal (AC). The abnormal rate of caloric test was the highest, followed by the abnormal rates of HC and PC gain. A significant difference of abnormal rate of HC gain was only found between the mild and moderate UISSNHL patients with and without vertigo (p = 0.029). CONCLUSION: Abnormal SCC function happens frequently in patients with profound hearing loss. Ipsilesional abnormal vHIT (especially the HC gain) in the presence of abnormal caloric test is a pattern of findings observed in mild and moderate UISSNHL patients with vertigo.

Comparisons among vestibular examinations and symptoms of vertigo in sudden sensorineural hearing loss patients.

OBJECTIVES: Vertigo in sudden sensorineural hearing loss (SSNHL) is hypothesized as an extension of the disease caused by the anatomical proximity of the cochlea and vestibule. The present study aimed to demonstrate the association of vestibular function test (VFT) results with SSNHL disease severity and prognosis. MATERIALS AND METHODS: This study assessed clinical records of 263 SSNHL patients admitted to our hospital, between January 2010 and October 2017. Steroid treatment comprised high-dose intravenous dexamethasone (16 mg/d) or oral methylprednisolone (64 mg/d) for 4 days and tapered oral methylprednisolone for 8 days after discharge. Caloric tests were performed in all patients, and cervical vestibular-evoked myogenic potential (c-VEMP) and ocular VEMP (o-VEMP) tests were performed in 209 and 144 patients, respectively. RESULTS: Ninety six patients had vertigo, and caloric abnormalities were observed in 119 patients. Initial PTA in patients with vertigo were worse than in those without vertigo (63.0 dB vs 72.7 dB, P = .002). Initial PTA in patients with abnormal o-VEMP was worse than in those with normal o-VEMP (61.4 dB vs 73.0 dB, P = .004). PTA improvement after steroid treatment in patients with vertigo was lower than in those without vertigo (25.0 dB vs 20.9 dB, P = .028). PTA improvement after treatment in patients with abnormal caloric results was lower than in those with normal caloric results (26.0 dB vs 18.4 dB, P = .013). CONCLUSION: The functions of vestibular organs, particularly the utricle and lateral semicircular canal, are associated with disease severity and hearing outcome in SSNHL patients.

Video head impulse test and caloric test in definite Ménière's disease.

PURPOSE: The objective of the study was to compare the results of caloric reflex tests and video head impulse tests (vHITs) of lateral semicircular canals (SCCs). METHODS: Patients aged over 18 years diagnosed with definite Ménière's disease (MD) according to the AAO-HNS 1995 criteria were recruited. Audiological tests, caloric tests and vHITs were conducted on all participants. A caloric weakness (canal paresis) of > 25% was considered significant. A VOR gain of < 0.8 in lateral or 0.7 in vertical SCCs was defined as significant. Patients were classified into active (having symptoms during the preceding 3 months) and inactive groups (free of symptoms for over 3 months). RESULTS: 51 patients (13 males and 38 females) participated. Caloric weakness was found in 39 patients (76.5%), while abnormal VOR gain was found in 24 (47.1%). The active group had 40 patients, and the inactive group had 11. There was statistical significance (p, 0.002) for disease duration but not for the caloric weakness and vHIT results of the two groups. Moreover, caloric weakness with an abnormal vHIT was not statistically significant, and there was no correlation between the two tests (r, 0.207) in lateral SCCs. The most common abnormal VOR gain in patients with caloric weakness was found in anterior SCCs. CONCLUSIONS: The caloric test can detect abnormalities of the vestibular function better than vHIT in all stages of MD. However, the vHIT showed more specificity for the detection of abnormal SCC function. The vHIT test can be used as a screening tool and the caloric test should be considered if a vHIT result is normal.

Ocular and cervical vestibular-evoked myogenic potentials in idiopathic sudden sensorineural hearing loss (ISSHL) without vertigo: VEMPs in ISSHL.

PURPOSE: Idiopathic sudden sensorineural hearing loss (ISSHL) is a hearing impairment greater than 30 dB at three consecutive frequencies developing in less than 3 days. The aim of this study was to evaluate VEMPs and caloric testing in patients affected by ISSHL without vertigo. METHODS: We retrospectively evaluated 35 subjects affected by ISSHL. The audio-vestibular investigation consisted of pure-tone and speech audiometry, impedance, bithermal caloric testing, oVEMPs and cVEMPs. RESULTS: VEMPS were abnormal in 21 patients (60%): cVEMPs in 12 (34.2%) and oVEMPs in 19 (54.2%). 10 patients (28.5%) presented with both c-and oVEMPs altered. Subjects without vestibular involvement showed a significant lower PTA in the affected ear both at admission and at discharge. Recovery rate was significantly higher in group without vestibular involvement. CONCLUSION: The evaluation of the vestibular system can be useful for predicting the auditory recovery in patients without vertigo also.

Nystagmus duration after caloric irrigations.

Objective: To measure nystagmus duration after warm and cool caloric water irrigations, with the aim of providing preliminary evidence for the optimum interval between irrigation onsets; and to compare nystagmus durations between warm and cool irrigations, in addition to maximum slow phase velocity (SPV).Design: Participants underwent up to four caloric irrigations during routine appointments. Nystagmus was recorded to minimal levels (within 2°/s of subject's baseline). The nystagmus duration and maximum SPV were measured.Study Sample: 52 vestibular assessment patients (99 ears).Results: The mean nystagmus duration was 183.9 s (seconds) (3:04 min) from irrigation onset, and nystagmus became minimal after 264.8 s (4:25 min) in 97.5% of this sample. The population mean is within ±6.7 s of the sample mean (p = <0.001). There was no significant difference between warm and cool irrigation durations, and correlation and linear regression analysis showed duration cannot reliably be predicted by maximum SPV.Conclusions: Mean nystagmus duration (3 min after irrigation onset) and nystagmus duration for 97.5% of patients (<4.5 min) were substantially less than the BSA recommended 7 min between irrigations. These findings provide preliminary evidence for shortening of intervals between stimulus onsets, regardless of irrigation temperature or maximum SPV, to reduce caloric testing time and improve clinical efficiency.