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Background: Patients with delayed endolymphatic hydrops (DEH) often show caloric hypofunction and endolymphatic hydrops (ELH) on gadolinium (Gd) enhanced magnetic resonance imaging (MRI) of the inner ear. Objectives: We aimed to investigate the relationship between the ELH in vivo and caloric results in ipsilateral DEH. Material and Methods: Twelve patients with ipsilateral DEH were included, who underwent delayed MRI following intratympanic Gd application, pure-tone audiometry, caloric test, and video head impulse test (vHIT). Results: For the affected ears, the overall prevalence of inner ear hydrops was 91.7%, including 75% in the cochlear and 50% in vestibular compartment. For the non-affected ears, the overall prevalence of inner ear hydrops was 25%, including 25% in cochlear and 16.7% in vestibular region. Caloric hypofunction was demonstrated in 75% of the affected ears. No pathologic vHIT were found. Caloric results were in agreement with the radiological evidence of inner ear hydrops on affected and non-affected ears in 9 cases. There was fair concordance between inner ear hydrops and canal paresis abnormality on the affected side. Conclusions and significance: MRI provides auxiliary evidence of ELH in vivo in the ipsilateral DEH-affected ears. The association between morphological alterations and caloric hypofunction warrants further investigation. [ABSTRACT FROM AUTHOR]

Background: Recent studies proved that certain proportions of vestibular schwannoma (VS) originated other than vestibular nerve of the eighth cranial nerve. Aims/objectives: Unlike air-conducted sounds (ACS) and bone-conducted vibration (BCV), galvanic vestibular stimulation (GVS) evokes vestibular evoked myogenic potentials (VEMPs) from the vestibular nerve. Materials and methods: Case-control study was conducted in unilateral VS patients pre-operatively. Healthy ears were controls. Patients examined ACS, BCV and GVS ocular VEMP (oVEMP) and cervical VEMP (cVEMP), caloric test, video head impulse test (vHIT), suppression head impulse paradigm (SHIMP) and pure tone audiometry (PTA). Results: Seven (26.9%) tumors affected left ear and 19 (73.1%) on the right(p <.05). Response rates in VS group were statistically lower than control except for ACS-cVEMP (p <.05). Response rates of VEMPs in VS patients decreased with the tumor size grows. But not all BCV and GVS VEMPs disappeared in the largest tumor group. Abnormal rates of caloric test, vHIT gains and SHIMP were found. Conclusions and significance: Response rates of GVS VEMPs decreased with the residual functional nerve fibers. GVS VEMPs help to differentiating labyrinthine and retro-labyrinthine lesions. GVS combined with BCV VEMPs probably reflex the tumor origin from the eighth cranial nerve and/or the remaining vestibular function. [ABSTRACT FROM AUTHOR]

Hearing loss is important in the diagnosis and treatment of Meniere's disease (MD). However, little is known about the factors associated with hearing changes in MD. This study aimed to investigate the correlation between hearing prognosis and caloric test (CT) results in MD. Ninety consecutive patients diagnosed with unilateral definite MD underwent pure tone audiometry (PTA) and CT at initial visits, and were re-tested PTA at the 6-month follow-up. Fifty-three of ninety MD patients (58.89%) had abnormal CT results. The change of PTA (cPTA = initial PTA-last PTA) was negatively correlated with canal paresis (CP) values (overall association p = 0.032 and non-linear association p = 0.413). Multivariate linear model showed that as the CP value changed from 0 to 1, the cPTA decreased by −13.31 dB (95% CI: −24.03, −2.6) (p = 0.016). Stratified analysis found that the association was present in MD patients of Stage 1 and 2 (p < 0.05) but not in patients of Stage 3 and 4 (p > 0.05). Elevated CP values may be linked to worse hearing outcomes in MD, especially in Stage 1 and 2 patients. Conducting a caloric test at the initial consultation may aid in assessing hearing regression in MD. [ABSTRACT FROM AUTHOR]

To compare the diagnostic accuracies of air caloric testing with electronystagmography and the vHIT (video-head impulse test). Prospective, controlled study. MD (Ménière's disease), 26; vestibular neuritis, 27; control, 56. 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. 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. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate subjective vestibulo-spinal reflex test sensitivity in subjects with unilateral vestibular loss. Forty subjects diagnosed with UVL within 7 days of onset and 30 subjects without dizziness/balance disorder complaints were included in the study as the unilateral vestibular loss and control groups (70 subjects aged 18–60 years [mean: 42.95 ± 10.82]). Bithermal caloric test, Fukuda, Babinski Weil, tandem walking, and past pointing tests were performed. The subjective VSR tests' sensitivities were compared among the various methods. The Fukuda test was determined to have the highest sensitivity value (65%; kappa coefficient: 0.352). The sensitivity values of the other tests, in descending order, are: Babinski Weil (55%, Kappa coefficient: 0.274), tandem walking (10%, Kappa coefficient: 0.022), and past pointing (2.5%, Kappa coefficient: −0.014). A positive moderate correlation was obtained between canal paresis asymmetry and Fukuda deviation degree (p = 0.009, r = 0.407). There was no correlation between Babinski Weil (p = 0.619), tandem walking (p = 0.538), and past pointing test results and canal paresis asymmetry (p > 0.05). Fukuda and Babinski Weil tests can be used under conditions where all subjective tests are not performed because of limited time. However, these tests must be used alongside objective vestibular test batteries owing to their limited specificity and sensitivity. [ABSTRACT FROM AUTHOR]

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 [ABSTRACT FROM AUTHOR]

The condition of vestibular dysfunction and blood flow in the vertebral artery (VA) in transient vascular vertigo/dizziness (TVV) is not well established. To clarify the pathophysiology of TVV, especially the difference between the isolation of vestibular symptoms. Ten TVV patients with central nervous system symptoms (TVVw) and 12 TVV patients without central nervous system symptoms (TVVo) underwent duplex color-coded ultrasonographic evaluation of VAs, caloric test, and cervical vestibular-evoked myogenic potential (cVEMP). The mean flow velocity (MV) ratio (peak MV of contralateral VA divided by target VA) was significantly higher in TVVw than in TVVo. There was no difference in the occurrence of canal paresis between TVVw and TVVo. Abnormal asymmetry ratios (ARs) of cVEMP were observed only in TVVo cases (6 of 12 cases), revealing a statistically significant difference in the number of cases between TVVw and TVVo. Measuring VAs using duplex color-coded ultrasonography and cVEMP may help evaluate TVV. Different results of MV ratio and cVEMP between TVV cases with or without central nervous system symptoms may indicate differences in the pathophysiology between TVVw and TVVo. [ABSTRACT FROM AUTHOR]

High-resolution MR imaging enables the visualization of individual nerves in the internal auditory canal (IAC). Cochlear nerve deficiency (CND) is recognized as one of the major causes of sensory neural hearing loss (SNHL), especially in cases of unilateral hearing loss in childhood. Some patients with CND are thought to have accompanying vestibular nerve deficiency (VND). However, there have been few reports focusing on VND and vestibular function in these children. The aim of this study was to evaluate the frequency of VND and vestibular dysfunction in children with unilateral SNHL caused by CND. Thirty-eight children with unilateral SNHL, who were diagnosed with CND by 3 T-MRI, were evaluated for VND and underwent caloric testing and cervical vestibular evoked potential (cVEMP). Fourteen of 38 patients (37%) had VND, and eleven (29%) of the patients [ten of the patients (71%) with VND] had at least one vestibular dysfunction. The patients with VND had significantly worse hearing and an IAC of smaller diameter than did patients without VND. We should pay attention to VND as well as vestibular dysfunction in hearing loss patients with CND. [ABSTRACT FROM AUTHOR]

The caloric test and the video head impulse test (vHIT) are diagnostic tools to examine vestibular neuritis (VN) patients through assessing the function of the semicircular canals. Both tests assess the vestibular ocular reflex (VOR) with major differences between them as regards stimulus characteristics, frequency, methodology and function examined. The caloric test is the gold standard test in VOR assessment. The vHIT assesses the same reflex (VOR) by using a video-assisted examination of the impulsive manoeuvre. The aim of this study was to assess the presence or absence of agreement between both vHIT and the caloric test in VN patients. A case-control study was conducted in Audiovestibular unit, Department of ENT, Zagazig University Hospitals. About 24 patients with VN were included. Both vHIT and the caloric test were done on two consecutive days. We assessed the agreement between these two tests. Horizontal gain asymmetry (GA) with the canal paresis. There was a slight agreement between both tests. The VHIT and the caloric test stimulate different frequencies of VOR. They are complementary rather than being alternatives in the diagnosis of peripheral VN. [ABSTRACT FROM AUTHOR]

To assess the effect of cochlear implantation on the function of the semicircular canals (SCC) and on experienced vestibular symptoms. Second, to determine the relation between vestibular test results. Retrospective cohort study assessing absolute and categorised results of caloric irrigation test, video Head Impulse Test (vHIT) and Dizziness Handicap Inventory (DHI) before and after cochlear implantation. Study sample: 192 patients, aged ≥7 years old, without preoperative areflexia. Mean maximum slow phase velocity decreased with 3.1°/s and 4.7°/s for warm and cold caloric irrigation respectively. About 37.4% of the patients deteriorated one or more categories on caloric testing. Complete caloric postoperative areflexia was found in 6.2%. Mean vHIT gain decreased with 0.06, 0.04 and 0.05 for anterior, lateral and posterior SCC, respectively. Seven patients (7.7%) acquired an abnormal gain value for the anterior SCC. Only mean score on DHI's physical subdomain rose significantly (1.4 points). Overall, 9.0% of the patients deteriorated one or two categories on DHI. Only few weak correlations were found between caloric test, vHIT and DHI shifts. Although mean objective and subjective-physical vestibular deteriorations were significant, its clinical impact seems limited. However, 9% of patients experience vestibular deterioration, thus, advocate assessment. Vestibular test results show no or merely weak mutual correlations. [ABSTRACT FROM AUTHOR]

Background: The caloric test has been used to evaluate the semi-circular canal function for decades. In 2009, the video head impulse test (vHIT) was introduced, which can be used to evaluate the semi-circular canal function within a short time. Although both tests examine the semi-circular canal, the stimulation methods differ and it is unclear whether the vHIT is equivocal to the caloric test. Aims/objectives: This study aimed to discern the differences between the vHIT and caloric test. Material and methods: This study comprised 112 patients with vertigo who visited the vertigo/dizziness centre at our university hospital. Each of these patients underwent a caloric test and vHIT within the same day, and their results were compared. Additionally, an electrocochleography (EcoG) examination, glycerol test (G test), and MRI (performed 4 h after an intravenous gadolinium injection) were conducted to evaluate the influence of endolymphatic hydrops (EH) on the caloric test and vHIT results. Results: Differences in the caloric test and vHIT results, among those with and without EH, were observed in 66.7 and 35.3% of patients, respectively. Conclusions and significance: EH resulted in a difference in results between the caloric test and vHIT. Activated hair cell type may also be implicated. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: The value of caloric tests in benign paroxysmal positional vertigo (BPPV) patients is unclear. Objectives: To analyze the features and clinical significance of caloric tests in BPPV patients. Materials and methods: About 2192 patients (256 BPPV and 1936 non-BPPV) who complained of dizziness triggered by movement, accompanied by the symptom of hearing loss or a history of vertigo, participated in this prospective clinical study. All subjects received a caloric test, 213 BPPV patients underwent follow-up for at least 6 months after canalith repositioning procedures (CRPs). Results: (1) The abnormal canal paresis (CP) prevalence of BPPV was 57%. (2) The curative rate of single CRP decreased during follow-up from 90.1% after 7 days to 61% after 6 months and was significantly lower in patients with (54.1%) than in those without (70.1%) an abnormal CP at 6 months post-treatment (p =.01). (3) The recurrent rate was significantly higher in BPPV patients with abnormal CP (25.2%) than with normal CP (12.5%; p =.017). Conclusions and significance: Patients with abnormal CP needed more CRPs and were more prone to relapse. The value of the caloric test in treatment planning and predicting recurrence in BPPV patients should be emphasized. [ABSTRACT FROM AUTHOR]

Objective: This study reviewed the development of the inner ear test battery comprising auditory brainstem response (ABR), and caloric, ocular vestibular-evoked myogenic potential (oVEMP), and cervical vestibular-evoked myogenic potential (cVEMP) tests in guinea pig models at our laboratory over the last 20 years. Detailed description of the methodology for testing the small animals is also included. Methods: Inner ear disorders, i.e. ototoxicity, noise exposure, or perilymph fistula were established in guinea pig models first. One to four weeks after operation, each animal underwent ABR, oVEMP, cVEMP, and caloric tests. Then, animals were sacrificed for morphological study in the temporal bones. Results: Inner ear endorgans can be comprehensively evaluated in guinea pig models via an inner ear test battery, which provides thorough information on the cochlea, saccule, utricle, and semicircular canal function of guinea pigs. Coupled with morphological study in the temporal bones of the animals may help elucidate the mechanism of inner ear disorders in humans. Conclusions: The inner ear test battery in guinea pig models may encourage young researchers to perform basic study in animals and stimulate the progress of experimental otology which is in evolution. [ABSTRACT FROM AUTHOR]

Conclusions:The step stimulus procedure can provide information on the time course of the vestibulo-ocular reflex. Spinocerebellar degeneration and aging seem to shorten the time constant of the onset of the vestibulo-ocular reflex, causing a rapid rise up. Failure of the central processing of velocity storage might contribute to this rapid rise up. Objectives:The aim of this study is to evaluate the time course characteristics of the vestibulo-ocular reflex in patients with spinocerebellar degeneration. Methods:Ten patients (20 ears) and 22 healthy subjects (30 ears) underwent caloric test using the step stimulus procedure. We evaluated the time course of caloric VOR and calculated the parameters of the time constant of an activation and adaptation response. We compared between the control and SCD groups to elucidate the time course characteristics of caloric VOR in patients with SCD. Results:Spinocerebellar degeneration seems to shorten the time constant of the activation response by caloric irrigation with 20 °C, 7l/min air. However, aging also possibly contributes to this shortening. No change was observed in the time constant of the adaptation response. [ABSTRACT FROM PUBLISHER]

Conclusion: The obtained simulations support the underlying hypothesis that the hydrostatic caloric drive is dissipated by local convective flow in a hydropic duct. Objective: To develop a computerized model to simulate and predict the internal fluid thermodynamic behavior within both normal and hydropic horizontal ducts. Methods: This study used a computational fluid dynamics software to simulate the effects of cooling and warming of two geometrical models representing normal and hydropic ducts of one semicircular horizontal canal during 120 s. Results: Temperature maps, vorticity, and velocity fields were successfully obtained to characterize the endolymphatic flow during the caloric test in the developed models. In the normal semicircular canal, a well-defined endolymphatic linear flow was obtained, this flow has an opposite direction depending only on the cooling or warming condition of the simulation. For the hydropic model a non-effective endolymphatic flow was predicted; in this model the velocity and vorticity fields show a non-linear flow, with some vortices formed inside the hydropic duct. [ABSTRACT FROM AUTHOR]

Conclusion:This study shows that, in cochlear implantation (CI) surgery, pre-operative caloric test results are not correlated with post-operative outcomes of dizziness or speech perception. Objectives:To determine the role of pre-operative caloric tests in CI. Methods:The records of 95 patients who underwent unilateral CI were reviewed retrospectively. Patients were divided into four groups according to caloric response. Forty-six patients with normal caloric responses were classified as Group A, 19 patients who underwent CI in the ear with worse caloric responses as Group B, 18 patients with bilateral loss of caloric responses as Group C, and 12 patients who underwent CI in the ear with better caloric responses as Group D. Speech performance and post-operative dizziness were compared between the four groups. Speech perception was determined by evaluating consonant-vowel phoneme detection, closed-set word and open-set mono-syllabic and bi-syllabic word identification, and sentence comprehension test scores. Results:The speech perception and aided pure-tone average (PTA) test results at 3 and 6 months and at 1, 2, and 3 years after implantation were not significantly different between Groups A, B, C, and D (p > 0.05). Eight patients (8.4%) reported post-operative dizziness, but there was no significant difference between the four groups (p = 0.627). [ABSTRACT FROM PUBLISHER]

Conclusion: This study shows that, in cochlear implantation (CI) surgery, pre-operative caloric test results are not correlated with post-operative outcomes of dizziness or speech perception. Objectives: To determine the role of pre-operative caloric tests in CI. Methods: The records of 95 patients who underwent unilateral CI were reviewed retrospectively. Patients were divided into four groups according to caloric response. Forty-six patients with normal caloric responses were classified as Group A, 19 patients who underwent CI in the ear with worse caloric responses as Group B, 18 patients with bilateral loss of caloric responses as Group C, and 12 patients who underwent CI in the ear with better caloric responses as Group D. Speech performance and postoperative dizziness were compared between the four groups. Speech perception was determined by evaluating consonant-vowel phoneme detection, closed-set word and open-set mono-syllabic and bisyllabic word identification, and sentence comprehension test scores. Results: The speech perception and aided pure-tone average (PTA) test results at 3 and 6 months and at 1, 2, and 3 years after implantation were not significantly different between Groups A, B, C, and D (p>0.05). Eight patients (8.4%) reported post-operative dizziness, but there was no significant difference between the four groups (p=0.627). [ABSTRACT FROM AUTHOR]

Conclusion Vestibular function in patients can be damaged following cochlear implantation. Therefore, assessing the pre-operative vestibular status, carefully choosing the side of implantation, and preserving function by using minimally invasive surgical techniques are important. Objectives The aim of this study was to assess the influence of cochlear implantation on vestibular function in patients with severe and profound sensorineural hearing loss, and to analyze a possible correlation between the changes in vestibular testing and post-operative vestibular symptoms. Methods Thirty-four patients were evaluated for vestibular function using the cervical and ocular vestibular-evoked myogenic potentials (cVEMP and oVEMP, respectively), and 29 patients underwent caloric tests pre-operatively and 4 weeks post-operatively. Results Before surgery, the cVEMPs were recorded bilaterally in 22 patients, unilaterally in eight patients, and absent bilaterally in four patients. The oVEMPs were recorded bilaterally in 19 patients, unilaterally in six patients, and absent bilaterally in nine patients. After implantation, the cVEMPs were absent in 10 patients and the oVEMPs were absent in seven patients on the implanted side. Caloric tests demonstrated canal paresis in 17 patients, and normal responses were recorded in 12 of the 29 patients pre-operatively. There was a significant decrease post-implantation in the ear implanted, with the exception of two patients. Two patients presented with vertigo and another two patients reported slight unsteadiness post-operatively, but all symptoms resolved within 7 days. The impaired vestibular function did not correlate with vestibular symptoms, age, or gender. Function on the contralateral side remained unaffected. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between hearing loss and vestibular dysfunction in patients with sudden sensorineural hearing loss (SSHL). Methods: Clinical data including the symptom of vertigo of 149 SSHL patients were investigated retrospectively. Pure tone audiometry, ocular vestibular-evoked myogenic potential (oVEMP) and cervical vestibular-evoked myogenic potential (cVEMP) evoked by air-conducted sound (ACS), and caloric test were employed for cochlear and vestibular function assessment. The relationship between hearing level and vestibular dysfunction was analyzed. Results: The pure tone averages (PTAs) (mean ± SD) of SSHL patients with and without vertigo were 88.81 ± 21.74 dB HL and 72.49 ± 21.88 dB HL (Z = −4.411,p = 0.000), respectively. The PTAs of SSHL patients with abnormal and normal caloric test were 84.71 ± 22.54 dB HL and 70.41 ± 24.07 dB HL (t = −2.665,p = 0.009), respectively. Conversely, vertigo and abnormal caloric results also happened more frequently in patients with profound hearing loss. However, no consistent tendency could be found among vestibular evoked myogenic potentials (VEMPs) responses or hearing loss. Conclusions: SSHL patients with vertigo or abnormal caloric test displayed worse hearing loss; and vice versa, vertigo and abnormal caloric results happened more frequently in SSHL patients with profound hearing loss. [ABSTRACT FROM PUBLISHER]

Conclusion: Contrast-enhanced magnetic resonance imaging (MRI) reveals variations in the endolymphatic morphology of the cystic lateral semicircular canal (CLSC) that correlate with inner ear function. This report is the first to suggest a relationship between the morphology and function of this common inner ear malformation in clinical cases. Objectives: This study investigated the radiological and functional findings of a common inner ear malformation using computed tomography (CT), gadolinium contrast-enhanced magnetic resonance imaging (MRI), caloric testing, and cervical and ocular vestibular evoked myogenic potential (VEMP) testing. Method: Four ears in three patients who were radiologically diagnosed with a CLSC and a normal cochlea on high-resolution CT and contrast-enhanced MRI were included. Semicircular canal and vestibular functions were analyzed using the caloric test and cervical and ocular VEMP testing. Results: Unilateral and bilateral cystic canals were found in two and one patients, respectively. In the first patient, the malformed vestibule and cystic space were separate on imaging, and perilymph filled the cystic space. The functional test results were normal. In the second patient, endolymph filled both cystic spaces, and the functional responses were poor. In the third patient, endolymph filled the cystic space, and the ear did not respond during functional testing. [ABSTRACT FROM AUTHOR]

Conclusions: Balance was improved at 365 days after CI in all patients. Caloric test findings were important determinants of balance outcomes over a year after CI. Pre-operative vestibular assessment findings should be documented because postural recovery over time depends on this information. Objective: To verify the importance of the caloric test as a pre-operative predictor tool of postural control after CI surgery. Methods: Prospective observational study made with 24 post-lingual deafness patients who underwent unilateral CI surgery. Vestibular assessments: questionnaire assessing vertigo, caloric tests, rotary chair (RC) testing, and computerized dynamic posturography (CDP), were sequentially performed for all patients before and 60, 120, 180, and 365 days after CI. Results: Thirteen patients (54.2%) reported dizziness before CI. At the end of the study, dizziness remained unchanged in one (7.7%) patient, ameliorated in 11 (84.6%), and worsened in one (7.7%). Baseline caloric tests identified 29.2% patients with normal reflexes, 33.3% with unilateral areflexia or hyporeflexia, 12.5% with bilateral hyporeflexia, and 25% with bilateral vestibular loss (BVL). Most patients exhibited objective improvements in postural stability. At 365 days, the CDP condition (particularly C5) and CS were higher for caloric tests responders at baseline than for those with BVL at baseline. [ABSTRACT FROM AUTHOR]

Conclusion: Both the bithermal caloric test and the video-head impulse test (vHIT) were more often abnormal in Ménière's disease (MD) than in vestibular migraine (VM). Horizontal vestibulo-ocular reflex (hVOR) evaluation with caloric test (low-frequency test) was significantly more often abnormal than vHIT (high-frequency test). Therefore, both tests can be used in a complementary way for frequency-selective testing of peripheral vestibular function. Objectives: To compare the results of caloric testing and vHIT in MD and VM and to determine which test is more sensitive to uncover peripheral vestibular hypofunction. Methods: Patients with MD ( n=30) or VM ( n=23) were examined with the caloric test and vHIT. The parameters analyzed were the canal paresis factor for the caloric test and the hVOR gain on both sides in vHIT. Results: The caloric test was abnormal in 67% of patients with MD and in 22% with VM ( p=0.002), while the vHIT showed an hVOR deficit in 37% in MD and 9% in VM ( p=0.025). In all, 28% of patients with an abnormal caloric test had a normal vHIT, whereas 6% of those with an abnormal vHIT had a normal caloric test. The sensitivity of vHIT compared with caloric testing was 55% for MD and 40% for VM. Neither the caloric test nor vHIT could detect significant differences between early (<5 years) or advanced stages (>5 years) of MD or VM. [ABSTRACT FROM AUTHOR]

Conclusions: The patients who received electric acoustic stimulation (EAS) cochlear implantation had relatively good vestibular function compared with the patients who did not have residual hearing. The vestibular function was well preserved after atraumatic EAS surgery. The round window approach and soft electrode are preferred to decrease the risk of impairing vestibular function. Objectives: The aim of this study was to examine the characteristic features of vestibular functions before and after implantations in patients undergoing EAS. Methods: Vestibular functions in patients who underwent EAS implantation were examined by caloric testing and vestibular evoked myogenic potential (VEMP) in 11 patients before and in 13 patients after implantation. Results: Preoperative evaluation showed that of the 11 patients, most (73%) had good vestibular function. One of 11 patients (9%) had decreased response in postoperative VEMP but all of the patients had unchanged results in postoperative caloric testing. [ABSTRACT FROM AUTHOR]

Conclusions: The degree of caloric weakness before surgery influences faster or slower recovery of patients undergoing vestibular schwannoma surgery. The Dizziness Handicap Inventory (DHI) is a good index to show the recovery of patients as it relates directly to an improvement or not of the subjective visual vertical (SW). Objective: To evaluate the process of recovery of patients as measured by the SW and the DHI after surgical removal of vestibular schwannoma. Methods: We studied 24 consecutive patients of the University Hospital of Salamanca who underwent vestibular schwannoma surgery. We assessed age, tumour size, degree of canalicular weakness and preoperative SW, and their relationship with DHI and SW at discharge and also at 1, 3 and 6 months postoperatively. Results: Patients with lesser degrees of caloric weakness took longer to normalize SW than those with a higher caloric weakness before surgery (p < 0.05). There was a significant correlation between DHI and improvements in SW with time. The differences disappeared in 6 months where all patients, with greater or lesser degree of caloric weakness, had the same results. [ABSTRACT FROM AUTHOR]

Conclusion: Vestibular abnormality was found in 84% of patients with Meniere's disease (MD) and 66% of those with migrainous vertigo (MV), even in the interictal period. Although MV does not have proven pathology like endolymphatic hydrops of MD, MV had high vestibular abnormality, suggesting that comorbid vestibular abnormality can be a cause of vertigo and needs to be pursued. Objectives: MD and MV are common disorders causing recurrent vertigo. We determined the vestibular abnormality rates using vestibular tests with objective measurements. Methods: Results of caloric, head-shaking nystagmus (HSN), and vibration-induced nystagmus (VIN) tests were analyzed in 45 patients with MD and 76 with MV. Results: The abnormal rates in MD were significantly higher than those in MV. Of 45 MD patients, 21 (47%), 32 (71%), and 24 (53%) exhibited abnormal caloric, HSN, and VIN results, respectively. Fourteen (31%) MD patients had migraine associated with vertigo, but the association was not accompanied by high rates of abnormal results in the tests. Of 76 MV patients, 19 (25%), 38 (50%), and 24 (32%) exhibited abnormal caloric, HSN, and VIN results, respectively. Overall, 84% of patients with MD and 66% with MV exhibited abnormal results on at least one test. Abnormal rates were highest in HSN, followed by VIN and the caloric test. [ABSTRACT FROM AUTHOR]

Conclusion. The inner ear monitoring system is useful for identifying the affected branches of the vestibular nerve in cases of vestibular neuritis, providing insight about the interval for the relief of vertigo. Objective: This study conducted an inner ear monitoring system including audiometry, and caloric, ocular vestibular evoked myogenic potential (oVEMP), and cervical VEMP (cVEMP) tests in cases of vestibular neuritis for assessing the affected branches of the vestibular nerve. Methods: Twenty patients with vestibular neuritis underwent caloric, oVEMP, and cVEMP tests. Type I indicates that one of the three tests is abnormal; type II indicates that two test results are abnormal; and type III indicates that no test result is normal. Results: All patients had normal hearing, bilaterally. Nineteen (95%) of 20 patients had abnormal caloric responses, 11 patients (55%) had abnormal oVEMPs, and 5 patients (25%) had abnormal cVEMPs. Restated, of all 20 patients, 8 patients were classified as type I, 9 were type II, and 3 were type III. The mean intervals between presentation and relief of vertigo were significantly different among the three types. One year after treatment, caloric, oVEMP, and cVEMP tests returned to normal responses in three (60%) of five patients. [ABSTRACT FROM AUTHOR]

Conclusion: Chances of hearing preservation are better in patients with vestibular schwannoma (VS) from the superior vestibular nerve (SVN) than from the inferior vestibular nerve (IVN). Pathologic posturography and electronystagmography (ENG) findings are more common in schwannomas from the SVN compared with tumors from the IVN. In this way, computerized dynamic platform posturography (CDPP) and ENG contribute to predict the nerve of origin of VS and can be used indirectly as a prognostic factor for hearing preservation. Objectives: To test whether preoperative CDPP or ENG results contribute to predict the nerve of origin in VS and also to evaluate the influence of the nerve of origin on hearing preservation. Methods: Eighty-nine patients with VS originating from the IVN and 22 patients with VS from the SVN were included. Hearing loss due to surgery was calculated on postoperative and preoperative audiograms. Caloric response was measured by ENG and condition 5 and 6 score were recorded by CDPP before surgery. Results: Hearing loss due to surgery was significantly lower in patients with tumors from the SVN than from the IVN ( p == 0.011). Pathologic results in preoperative ENG ( p < 0.0001) and CDPP ( p == 0.025) were significantly more frequent in subjects with SVN than with IVN schwannomas. [ABSTRACT FROM AUTHOR]

The influence of aging on hearing and vestibular function in patients with auditory neuropathy has not been investigated. The purpose of this study was to investigate how hearing and vestibular function in this disease change with aging. The subjects were three female patients with auditory neuropathy. We checked their hearing and vestibular function by speech discrimination tests, ABR, ECochG, DPOAE, caloric test, damped-rotational chair test, and VEMPs. In all three patients, speech discrimination ability and vestibular function markedly declined with aging. However, speech language understanding and higher brain function were less affected by aging. [ABSTRACT FROM AUTHOR]

Conclusion: GJB2 mutations are responsible not only for deafness but also for the occurrence of vestibular dysfunction. However, vestibular dysfunction tends to be unilateral and less severe in comparison with that of bilateral deafness. Objectives: The correlation between the cochlear and vestibular end-organs suggests that some children with congenital deafness may have vestibular impairments. On the other hand, GJB2 gene mutations are the most common cause of nonsyndromic deafness. The vestibular function of patients with congenital deafness (CD), which is related to GJB2 gene mutation, remains to be elucidated. The purpose of this study was to analyze the relationship between GJB2 gene mutation and vestibular dysfunction in adults with CD. Methods: A total of 31 subjects, including 10 healthy volunteers and 21 patients with CD, were enrolled in the study. A hearing test and genetic analysis were performed. The vestibular evoked myogenic potentials (VEMPs) were measured and a caloric test was performed to assess the vestibular function. The percentage of vestibular dysfunction was then statistically analyzed. Results: The hearing level of all CD patients demonstrated a severe to profound impairment. In seven CD patients, their hearing impairment was related to GJB2 mutation. Five of the seven patients with CD related to GJB2 mutation demonstrated abnormalities in one or both of the two tests. The percentage of vestibular dysfunction of the patients with CD related to GJB2 mutation was statistically higher than in patients with CD unrelated to GJB2 mutation and in healthy controls. [ABSTRACT FROM AUTHOR]

Conclusions: Our study revealed that VEMPs in responses to clicks and 500 Hz STB were abnormal in 25% of athletes with congenital profound sensorineural hearing loss for the Deaf Olympic Games. These results confirm that a part of deaf athletes with congenital vestibular failure is well compensated for higher level sport activities. Objectives: The aim of this study was to investigate the appearance rate of VEMP, vestibular failure and its compensation in Japanese deaf athletes by the VEMP test, caloric test and balance test. Methods: Sixteen subjects among the Deaf Olympic Games athletes of Japan volunteered to participate in this study. All the subjects have congenital profound sensorineural hearing loss. Results: In the VEMP test, 24 ears (75%) showed normal click-evoked responses, 5 ears (16%) showed decreased click-evoked responses, 3 ears (9%) showed no click-evoked responses, 28 ears (87.5%) showed normal 500 Hz short tone burst (STB)-evoked responses and 4 ears (12.5%) showed decreased responses. In the ice-water caloric test, 11 subjects (69%) showed normal responses bilaterally, 3 subjects showed bilateral responses with asymmetrical responses and 2 subjects (12%) showed no response bilaterally. All the subjects showed normal balance test results. [ABSTRACT FROM AUTHOR]

Conclusion: We developed a new coordinates system for magnetic resonance imaging (MRI) that utilizes the labyrinth and eyeballs as references to measure the spatial arrangement of cranial organs, and we verified its usefulness by observing small structures in the labyrinth in 39 ears from 33 patients. Our new coordinates system could be used for stereotactic analysis of cranial organs in MRI. Objectives: To research semicircular canal anatomy in healthy organisms, we propose a method that employs references visible on MRI for stereotactic measurement of cranial structures, and we evaluated the usefulness of our method. Methods: Using the new coordinates system and vector analysis, we calculated angles among the semicircular canals and sagittal head plane from MRI volume data containing temporal bone and orbit. Results: The angle between the anterior semicircular canal plane and sagittal plane was 35.3 ± 4.1°; posterior semicircular canal plane and sagittal plane, 50.9 ± 4.7°; and horizontal semicircular canal plane and sagittal plane, 90.4 ± 7.0°. The angle between the anterior and posterior semicircular canal planes was 95.1 ± 4.2°; anterior and horizontal semicircular canal planes, 92.3 ± 7.5°; and posterior and horizontal semicircular canal planes, 93.5 ± 4.9°. [ABSTRACT FROM AUTHOR]

Conclusions: Three possible results are commonly seen after ice-water caloric irrigation and to correctly interpret them the function of the corresponding vestibular receptor and of normal endolymphatic flow must be taken into account. Bedside vestibular examination helps to interpret discrepant findings. Objective: To review the findings obtained with the ice-water caloric test in patients with dizziness and to compare the results with those of the bedside test. Patients and methods: The study was undertaken in a university hospital, tertiary medical center. The indications to perform the ice-water caloric test were: 1) unilateral canal weakness >90%; 2) a maximum slow phase velocity of nystagmus after hot (44°C) and cold (30°C) caloric stimulation in either ear of <9° s–1; or 3) in both ears <15° s–1. After irrigating the ear with ice water, nystagmus was recorded in the face-up and face-down positions. The result of the test was classified as a response (nystagmus beats away from the irrigated ear in the supine position and changes when in prone), a gravity-independent response (nystagmus does not change in direction in the prone position) or no response. The spontaneous and post head-shaking nystagmus, as well as the results of the head-impulse test, were also analyzed. When indicated, a rotatory chair test was performed. Results: In the 71 patients that displayed unilateral hypofunction, the ice-water test produced a normal response in 24, a gravity-independent response in 31, and no response in 14. In two of these patients a vertical gravity-independent nystagmus response was observed. Bilateral hypofunction was found in 12 patients and the results in the head-impulse test were in agreement with the results in the ice-water test. [ABSTRACT FROM AUTHOR]

Conclusions. The results of the caloric test, vestibular evoked myogenic potential (VEMP), and auditory brainstem response (ABR) in patients with vestibular schwannoma (VS) did not show clear correlation with the nerve origin of the tumor but with tumor size. When we focused on patients with VS within the internal acoustic canal (IAC), neither the nerve origin of the tumor nor the tumor size showed clear correlation with the results of these tests. Objectives. This study examined the correlation of the nerve origin of VS, superior or inferior vestibular nerve, with the results of function tests. Subjects and methods. Subjects comprised 109 consecutive patients diagnosed as having unilateral VS. Each test was performed before surgery. Tumor size was measured with preoperative MRI. Results. The nerve origin of the tumor was identified in 63 of the 109 patients. The percentage of patients showing abnormal responses in each test was not different between 37 patients with superior VS and 26 patients with inferior VS. Also, no difference was observed for patients with VS within the IAC. Mean tumor size in patients showing abnormal responses was larger than that in patients showing normal responses on each test. However, this tendency was not observed for patients with VS within the IAC. [ABSTRACT FROM AUTHOR]

Conclusion. Abnormal caloric and vestibular evoked myogenic potential (VEMP) responses are frequently encountered with a large cerebellopontine angle (CPA) schwannoma, while normal caloric responses and abnormal VEMPs are noted with a large CPA meningioma. This difference may possibly exist because schwannoma causes vestibular deficits via parenchymal involvement, while vestibular deficits in the meningioma are mostly due to compression neuropathy. Objectives. This study aimed to compare the tumor characteristics in relation to vestibular function, i.e. caloric and VEMP responses, between large-sized (>2.5 cm) meningioma and schwannoma in the CPA. Patients and methods. Five patients with large CPA meningioma and nine patients with large CPA schwannoma were enrolled in this study. Each patient underwent a battery of tests including audiometry, caloric test, VEMP test, and MRI study. Results. The meningioma group showed 20% caloric abnormality and 75% VEMP abnormality, while the schwannoma group revealed 100% caloric and 100% VEMP abnormalities. A significant difference existed in relation to caloric abnormality between the two groups, but not in relation to VEMP abnormality. [ABSTRACT FROM AUTHOR]

Congenitally deaf infants and children commonly suffer vestibular failure in both ears, and impairment of postural control, locomotion, and gait. The development of gross motor functions, such as head control, sitting, and walking is likely to be delayed, but fine motor function is usually preserved unless disorders of the central nervous system are present. These children can eventually catch up with their normal peers in terms of development and growth as a result of central vestibular compensation. The visual and somatosensory systems, pyramidal and extrapyramidal motor system (cerebellum, basal ganglia, cerebrum) and intellectual development, compensate for vestibular failure in infants and children with congenitally hypoactive or absent function of the semicircular canals and otolith organs. [ABSTRACT FROM AUTHOR]

Conclusion. Subjectivity seems to play a definite role in the interpretation of the pendular test, but somewhat less for caloric testing, where pure visual analysis seems to be more reliable. Automated values provided by proof-tested software may be useful. Objectives. In some centers, the interpretation of videonystagmography is still based on direct visual analysis of recorded tracings. Our study addresses the importance of subjectivity in the interpretation of videonystagmographic readings. Patients and methods. Two experts (one junior and the other senior) were asked to interpret the same caloric and pendular tests on two different occasions, 3 months apart. Initial reading was performed without knowledge of the patient's history or the results of other neuro-otological tests. Three months later, interpretations were done with complete access to the patient's charts. The experts' answers were compared to the values provided by the computer software. Results. For the pendular test, inter-expert agreement was poor. With knowledge of the patient's history, the expert's interpretations tended to coincide with the software's calculations. For the caloric test, interpretation was less variable. [ABSTRACT FROM AUTHOR]

Conclusion. The tumor size of acoustic neuroma correlates with cochleovestibular deficits. Those tumors with global frequency hearing loss, bilateral gaze nystagmus, or absent caloric and VEMP responses may indicate a tumor size >2.5 cm. Objective. This study aimed to investigate the correlation between cochleovestibular deficits and the size of acoustic neuroma. Patients and methods. A total of 44 patients with acoustic neuroma were enrolled in this study. Pure tone audiometry, electronystagmography, caloric test, vestibular evoked myogenic potential (VEMP) test, and MRI were conducted. Results. There is a trend of correlation between tumor size and audiographic configuration, with small-sized tumor in normal and rising types, medium-sized tumor in mid- and high-frequency hearing loss, and large-sized tumor in flat and deafness types. Five patients with bilateral gaze nystagmus had significantly larger tumor size than those without nystagmus. When 1 and 0 are used to represent abnormal and normal responses, respectively, the relationship between tumor size and vestibular function can be expressed as: tumor size (cm)=1.43 (caloric response)+1.35 (VEMP response), indicating that the estimated tumor size for those with abnormal caloric or VEMP responses increased by 1.43 or 1.35 cm, respectively. [ABSTRACT FROM AUTHOR]

We report a case of mumps deafness with acute vestibular symptoms secondary to both retrolabyrinthine and inner ear dysfunction. To our knowledge, no such case has been reported elsewhere. The patient was a 6-year-old girl in whom mumps deafness was initially diagnosed. Two days after onset of the hearing impairment, severe vertigo developed. Neurotologic examinations revealed spontaneous right-beating nystagmus, left canal paresis, absence of vestibular-evoked myogenic potentials in the left ear, and absence of responses to a left galvanic body sway test (GBST). The vertigo resolved 7 days after onset. However, the left hearing impairment progressed to complete deafness. Six months later, left canal paresis was still present, but bilateral GBST responses were normal, suggesting that retrolabyrinthine vestibular function had been restored. Mumps virus may affect retrolabyrinthine function as well as the inner ear. [ABSTRACT FROM AUTHOR]

Conclusion. The skull vibration-induced nystagmus test (SVINT) is a useful complementary test to the caloric test, which evaluates very low frequencies, and the head shaking test (HST), which explores medium range frequencies. These three tests are fully correlated in total unilateral vestibular lesions (tUVL) with a sensitivity of 98% and a specificity of 94% for the SVINT. The results of the interference of the SVINT with the cold caloric test on the intact ear suggest that different vestibular sensory cells are involved in these two tests. The stimulus location optimization suggests that vibrations directly stimulate the inner ear on the intact side. Objectives. The aim of this study was to establish the effectiveness of a rapid, non-invasive test used to detect vestibular asymmetry at 30, 60 and 100 Hz stimulation in tUVL. Patients and methods. The high frequency vibration test applied to the skull using the SVINT was compared to the results of HST and caloric test in 134 patients and 95 normal subjects: 131 patients had a total unilateral vestibular dysfunction and 3 had a bilateral total lesion (tBVL). The effects of stimulus frequency, topography and head position were studied using a video-nystagmograph. Results. In tUVL, the SVINT always revealed a lesional nystagmus beating toward the healthy side at all frequencies. The mastoid site was more efficient than the cervical and vertex sites (p<0.005). The mean skull vibratory nystagmus (SVN) slow phase velocity (SPV) is 10.7°/s (SD =7.5; n=20). Mastoid stimulation efficiency was not correlated with the side of stimulation. SVN SPV was correlated with the total caloric efficiency on the healthy ear (p=0.03). The interference of the SVINT during the cold caloric test on the intact ear demonstrated a reversal of the caloric nystagmus at each application of the vibrator. In tBVL, SVINT revealed no nystagmus. [ABSTRACT FROM AUTHOR]

Conclusion. Testing of the horizontal vestibulo-ocular reflex (VOR) with head rotations (including head impulses) using the magnetic scleral search coil technique (SCT HHI) provides valuable additional diagnostic information in patients with persistent dizziness, oscillopsia or imbalance. It identifies high and low frequency/acceleration vestibular abnormalities that are frequently missed using other methods. Objectives. To evaluate the diagnostic utility of SCT measurement of the horizontal VOR in the multidisciplinary neurotology clinic of a tertiary referral centre. Patients and methods. The records of 127 consecutive patients referred for persistent dizziness, oscillopsia, imbalance, or with clinical findings suggestive of high frequency/acceleration vestibular dysfunction were reviewed. All had been tested with clinical head impulses, bithermal calorics and vestibular-evoked myogenic potentials. VOR gain (peak eye velocity/peak head velocity) had been measured both in response to sinusoidal oscillations in a rotating chair (0.1-11Hz) and to manually delivered horizontal head rotations (peak head velocities 50-500°/s) using SCT. Results. Agreement between the different test modalities of horizontal semicircular canal function was moderate. Relative to SCT HHI, clinical HHI showed the highest sensitivity and the lowest specificity (both 70%). SCT HHI appeared to have the greatest diagnostic yield, when compared with calorics and SCT ROT (23% of all abnormalities shown were detected only by SCT HHI) and also allowed detection of significant asymmetries in patients with bilateral vestibular dysfunction. [ABSTRACT FROM AUTHOR]

Conclusion. Condition-5-score (C5S) and condition-6-score (C6S) of computerized dynamic platform posturography (CDPP) can detect the presence of a functional deficit of the lateral semicircular canal (and the superior vestibular nerve), irrespective of the central vestibular compensatory status, in vestibular schwannoma (VS) patients. Objectives. To test whether CDPP findings differ between VS patients with and without asymmetry on caloric and/or rotational ENG studies. Patients and methods. This was a retrospective review of 216 consecutive patients with VS. C5S and C6S of CDPP (Equitest®) were compared among patients with normal caloric and rotational studies, patients with asymmetry on caloric studies and normal rotational studies, and patients with asymmetric caloric and rotational studies using the Wilcoxon-Mann-Whitney test. Results. C5S and C6S of VS patients with normal caloric and rotational studies were significantly higher than in VS patients with either asymmetry on both rotational and caloric test results (p<0.001 for both C5S and C6S) or normal rotational studies and asymmetry on caloric testing (p<0.001 for both C5S and C6S). Neither C5S nor C6S were significantly different between patients with asymmetry on caloric testing and normal rotational studies and patients with asymmetry on both rotational and caloric testing. [ABSTRACT FROM AUTHOR]

Conclusions. Inferior vestibular nerve functions could recover in patients with vestibular neuritis (VN). Objectives. Although the recovery of superior vestibular nerve functions has been reported, there is little information about the recovery of inferior vestibular nerve functions in patients with VN. This study was done to clarify if inferior vestibular nerve functions recover after an attack of VN. Methods. Neuro-otological tests including vestibular evoked myogenic potential (VEMP) testing and caloric testing were sequentially performed in 13 patients with VN, who showed absence of VEMP on the affected side at the initial examination (7 men and 6 women, 28–82 years of age). VEMPs to click stimulation (95 dBnHL) were recorded with surface electrodes over each sternocleidomastoid muscle. Results. Among the 13 patients, 5 patients (4 men and 1 woman) showed recovery of VEMP responses. Four of the five patients (three men and one woman) showed recovery of VEMP to the normal range. It takes 6 months to 2 years to recover within the normal range. On the other hand, caloric responses recovered to the normal range only in one patient. [ABSTRACT FROM AUTHOR]

Conclusion . If the high-frequency (HF) component of the R–R interval spectrum of the electrocardiogram (ECG) increases after the first stimulation during a bithermal caloric test, subsequent repeated stimulations may be likely to induce autonomic symptoms such as nausea. Objective . Nausea often occurs as a vestibulo-autonomic symptom during the caloric test. However, there have been only a few clinical studies of autonomic activity during this test. To determine whether certain factors can predict the development of nausea, we performed an autonomic function test by means of R–R interval spectral analysis of the ECG during caloric testing. Material and methods . The study subjects were 53 healthy volunteers aged 22–39 years (41 males, 12 females; mean age 25.3 years) and a 35-year-old male patient with a labyrinthine defect. The caloric test was performed in 43 subjects using an air caloric apparatus with bithermal stimulation of alternate ears. After each stimulation, the subjects were asked about autonomic symptoms. Serial ECG records were obtained and R–R interval spectral analysis was performed. Results . Severe nausea was observed in 12 subjects (28%). In the group with severe nausea, the HF component of the R–R interval spectrum increased after the first caloric stimulation when autonomic symptoms had not yet become marked. [ABSTRACT FROM AUTHOR]

An order effect, characterized by a progressive decline in response magnitude, has been observed in the caloric test, and it has been suggested that the effect may be countered by applying a correction. This study was undertaken to determine whether the effect has its origin in physiological adaptation or in calibration drift of the recording system. Thirty-two normal subjects underwent the caloric test, in which their nystagmus was monitored simultaneously by both electronystagmography (ENG) and videonystagmography (VNG). The experimental design also allowed other aspects of the caloric test sequence to be investigated. No evidence of physiological adaptation of the response was seen. However, there was a significant change in corneo-retinal potential, and hence ENG calibration, during the tests. This was more marked if subjects' eyes were maintained in darkness. It is recommended that no correction be made for order effects but that the calibration of ENG-based systems is adjusted immediately prior to each caloric irrigation. [ABSTRACT FROM AUTHOR]

Objective --To study nystagmus-sensation dissociation (NSD), i.e. caloric nystagmus without the sensation of vertigo, in patients with spinocerebellar degeneration (SCD). Material and Methods --The neuro-otological and neuro-radiological records of 179 patients clinically diagnosed as having SCD (91 males, 88 females; age range 20-89 years) and 48 patients diagnosed as having peripheral vestibular disorders (15 males, 33 females; age range 21-80 years) were reviewed. Subjects underwent caloric tests using cold water (20°C) in a totally dark room. Immediately after each test session, subjects were asked if they had experienced spinning or moving sensations during the test. Maximum slow phase eye velocities (SPEVs) were measured using electronystagmography. Results --Among patients with peripheral vestibular disorders, all patients with SPEVs >15°/s experienced spinning or moving sensations during testing. Among the 179 patients with SCD, 21 (39 sides) showed maximum SPEVs >15°/s without spinning or moving sensations. In particular, 8 patients (10 sides) had maximum SPEVs >25°/s without spinning or moving sensations. Common lesions in the cerebral cortex could not be detected using either MRI or single-photon emission CT. Conclusion --Patients with SCD may also have NSD, which may be attributable to subcortical lesions in the ascending pathways to the vestibular cortex. [ABSTRACT FROM AUTHOR]

In order to assess the influence of canal paresis and compensation on the yaw-axis rotatory chair test parameters gain and time constant, a study was conducted in 435 patients diagnosed with unilateral peripheral vestibulopathy. Patients were grouped according to the amount of canal paresis found in the caloric test and by the result of a bedside examination of the vestibulo-ocular reflex (VOR). The time constant of the VOR diminishes as canal paresis increases and, when using a high-velocity sinusoidal test, there is a similar reduction in gain. Mean time constant was reduced when rotations were to the side of the lesion (ipsilesional) and to the normal (contralesional) and differences between both rotations were found for 21-80% canal paresis. Ipsilesional gain was significantly less than contralesional gain, which had a normal result independent of the amount of canal paresis; differences between them were significant when canal paresis was > 41%. Spontaneous nystagmus significantly influenced the appearance of asymmetries in gain and time constant in the tests performed while, with high-velocity sinusoidal rotation, gain was found to be significantly different for ipsilesional and contralesional rotations in non-acute symptomatic patients. [ABSTRACT FROM AUTHOR]

Eight patients diagnosed with vestibular neuritis received the newly developed three-dimensional videonystagmography (3D VNG) and vestibular evoked myogenic potential (VEMP) examination in order to localize the lesion site. Two (25%) of the 8 patients exhibited spontaneous nystagmus with 3 components, indicating that both the horizontal semicircular canal (HSCC) and anterior semicircular canal (ASCC) were affected. The remaining 6 patients (75%) displayed only horizontal nystagmus, meaning that only the HSCC was involved. Seven (88%) of the 8 patients had bilateral normal VEMPs, revealing sparing of the posterior semicircular canal (PSCC). In a comparative study, another seven patients with vestibular neuritis 1 year post-treatment also received the caloric test, 3D VNG and VEMP examination. Only one patient exhibited spontaneous nystagmus. An absent caloric response of the lesioned side persisted in 5 (71%) of the 7 patients. However, all patients showed normal VEMPs bilaterally. 3D VNG and VEMP examination indicates that vestibular neuritis mainly affects the superior division of the vestibular nerve, which innervates the HSCC and ASCC. Meanwhile, the function of the PSCC and saccule, innervated by the inferior vestibular nerve, is preserved. [ABSTRACT FROM AUTHOR]

Cephalic tetanus is a rare form of tetanus, defined by paralysis of more than one cranial nerve. The seventh cranial nerve is the most frequently involved. We report a 58-year-old man with cephalic tetanus and bilateral vestibulopathy. The patient's initial symptoms were rotatory vertigo and hypertension. He then developed trismus and cranial nerve palsies of the fifth and seventh nerves. The caloric test and vestibular evoked mygenic potentials in response to air-conducted clicks revealed absent responses on both sides, although audiometry and auditory brainstem responses were normal in both ears. To the best of our knowledge, this is the first report of involvement of the eighth cranial nerve in cephalic tetanus. [ABSTRACT FROM AUTHOR]

Abstract This brief study investigates the extent and origin of the apparent dependency of air delivery speculum size on the effectiveness of air used as a stimulus in the bi-thermal caloric test, using water as a reference stimulus. Eleven normal volunteers served as subjects. Six caloric stimulus delivery conditions included air with two speculum sizes, speculum only and with a rubber tube extension, and water. The resulting nystagmus was used as an index of stimulus efficiency. The effectiveness of the air stimulus was found to be dependent on the diameter of the speculum used for air delivery. The narrower speculum generated nystagmus that was typically twice that generated by the wider speculum. Users of air caloric equipment whose design includes a speculum that influences the effectiveness of the stimulus should be aware of this dependency and ensure their clinical interpretation of results is made with reference to appropriate normative data. Sumario Este breve estudio investigó la dimensión y el origen de la aparente dependencia del tamaño de la punta de estimulación, en la efectividad del aire que se usa como estímulo en la prueba calórica bitermica, usando agua como estímulo de referencia. Once voluntarios normales sirvieron como muestra. Seis condiciones de estimulación incluyeron aire con dos tamaños de espéculos, un espéculo aislado o con un tubo de extensión de hule, y agua. El nistagmo resultante se usó como índice de la eficiencia del estímulo. Se encontró que la efectividad del estímulo con aire es dependiente del diámetro del espéculo usado para el envío del aire. El espéculo más estrecho, generó un nistagmo que fue típicamente del doble que el generado con el espéculo más ancho. Los usuarios de equipo calórico con aire, cuyo diseño incluye un espéculo, deben estar concientes de esa dependencia y estar seguros de que sus interpretaciones clínicas de los resultados, se hagan con referencia a datos normativos apropiados. [ABSTRACT FROM AUTHOR]