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.

Preoperative Differences in Intracranial Facial Versus Vestibular Schwannomas: A Four Nerve Assessment.

OBJECTIVES: Assesses whether preoperative functional testing can distinguish vestibular schwannomas from facial nerve schwannomas medial to the labyrinthine segment. STUDY DESIGN: Retrospective cohort. METHODS: Retrospectively review surgically managed intracranial facial and vestibular schwannomas between January 2015 and December 2019 at two tertiary care centers. Patients with neurofibromatosis 2 and surgery for recurrence were excluded. Preoperative functional testing to include House-Brackmann scores, electroneuronography (ENoG), cervical vestibular evoked myogenic potentials (cVEMP), caloric testing, acoustic brainstem responses (ABRs), acoustic reflexes, and audiograms was compared between the two groups of schwannomas. RESULTS: Twelve facial and 128 vestibular schwannomas met inclusion criteria. In only one case was a facial schwannoma diagnosed preoperatively from imaging. No statistically significant difference was found in preoperative House-Brackmann scores, ENoG, cVEMP, caloric testing, ABRs, or acoustic reflexes. Pure tone average was worse in the vestibular schwannoma group (63 dB [95% CI: 58-68 dB] vs. 46 dB [95% CI: 34-58 dB], P = .01), and the difference was more apparent in the lower frequencies. Word recognition score was better in the facial schwannoma group (66% [95% CI: 45-86%] vs. 41% [95% CI: 34-47%], P = .02). CONCLUSION: Specialized preoperative functional evaluation of the nerves of the internal auditory canal cannot reliably predict the presence of an intracranial facial schwannoma. Hearing is better in facial schwannomas, particularly in the lower frequencies. This should raise the index of suspicion for an intracranial facial schwannoma, especially in candidates for hearing preservation vestibular schwannoma surgery. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:2098-2105, 2021.

Prospective cohort study on the predictors of fall risk in 119 patients with bilateral vestibulopathy.

OBJECTIVES: To identify predictive factors for falls in patients with bilateral vestibulopathy (BV). Specific variables contributing to the general work-up of a vestibular patient were compared between BV patients experiencing falls and those who did not. DESIGN: Prospective multi-centric cohort study. SETTING: Department of Otorhinolaryngology & Head and Neck Surgery at two tertiary referral centers: Antwerp University Hospital and Maastricht University Medical Center. PARTICIPANTS: In total, 119 BV patients were included. BV diagnosis was defined in accordance with the diagnostic BV criteria, established by the Bárány Society in 2017. MAIN OUTCOME MEASURES: Patients were divided into fallers and non-fallers, depending on the experience of one or more falls in the preceding 12 months. Residual vestibular function on caloric testing, rotatory chair testing, video head impulse test (vHIT) and cervical vestibular evoked myogenic potentials (cVEMP) was evaluated as a predictive factor for falls. Furthermore, hearing function (speech perception in noise (SPIN)), sound localization performance, etiology, disease duration, sport practice, scores on the Dizziness Handicap Inventory (DHI) and the Oscillopsia Severity Questionnaire (OSQ) were compared between fallers and non-fallers. RESULTS: Forty-five (39%) patients reported falls. In a sub-analysis in the patients recruited at UZA (n = 69), 20% experienced three or more falls and three patients (4%) suffered from severe fall-related injuries. The DHI score and the OSQ score were significantly higher in fallers. Residual vestibular function, SPIN, sound localization performance, etiology, disease duration, age and sport practice did not differ between fallers and non-fallers. CONCLUSIONS: Falls and (severe) fall-related injuries are frequent among BV patients. A DHI score > 47 and an OSQ score > 27.5 might be indicative for BV patients at risk for falls, with a sensitivity of 70% and specificity of 60%. Residual vestibular function captured by single vestibular tests (vHIT, calorics, rotatory chair, cVEMP) or by overall vestibular function defined as the number of impaired vestibular sensors are not suitable to distinguish fallers and non-fallers in a BV population.

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.

Caloric test and video head impulse test sensitivity as vestibular impairment predictors before cochlear implant surgery.

OBJECTIVES: Currently, cochlear implant procedures are becoming increasingly broad and have greatly expanded. Bilateral cochlear implants and cochlear implants are more frequently applied in children. Our hypothesis is that the video head impulse test may be more sensitive than the caloric test in detecting abnormal vestibular function before cochlear implant surgery. The objective of this study was to compare the video head impulse test and caloric test results of patients selected for cochlear implant procedures before surgery. METHODS: The patients selected for cochlear implant surgery were submitted to a bithermal caloric test and video head impulse test. RESULTS: By comparing angular slow phase velocity values below 5° in the bithermal caloric test (hypofunction) and video head impulse test with a gain lower than 0.8, we identified 37 (64.9%) patients with vestibular hypofunction or canal paresis and 21 (36.8%) patients with abnormal video head impulse test gain before the cochlear implant procedure. Of the 37 patients with caloric test vestibular hypofunction, 20 (54%) patients exhibited an abnormal gain in the video head impulse test. CONCLUSION: The caloric test is more sensitive than the video head impulse test (Fisher's exact test, p=0.0002) in detecting the impaired ear before cochlear implant delivery. The proportion of caloric test/video head impulse test positive identification of abnormal vestibular function or caloric test/video head impulse test sensitivity was 1.8:1.

Caloric test and video head impulse test sensitivity as vestibular impairment predictors before cochlear implant surgery

OBJECTIVES: Currently, cochlear implant procedures are becoming increasingly broad and have greatly expanded. Bilateral cochlear implants and cochlear implants are more frequently applied in children. Our hypothesis is that the video head impulse test may be more sensitive than the caloric test in detecting abnormal vestibular function before cochlear implant surgery. The objective of this study was to compare the video head impulse test and caloric test results of patients selected for cochlear implant procedures before surgery. METHODS: The patients selected for cochlear implant surgery were submitted to a bithermal caloric test and video head impulse test. RESULTS: By comparing angular slow phase velocity values below 5° in the bithermal caloric test (hypofunction) and video head impulse test with a gain lower than 0.8, we identified 37 (64.9%) patients with vestibular hypofunction or canal paresis and 21 (36.8%) patients with abnormal video head impulse test gain before the cochlear implant procedure. Of the 37 patients with caloric test vestibular hypofunction, 20 (54%) patients exhibited an abnormal gain in the video head impulse test. CONCLUSION: The caloric test is more sensitive than the video head impulse test (Fisher's exact test, p=0.0002) in detecting the impaired ear before cochlear implant delivery. The proportion of caloric test/video head impulse test positive identification of abnormal vestibular function or caloric test/video head impulse test sensitivity was 1.8:1.

Effects of cavity reconstruction on morbidity and quality of life after canal wall down tympanomastoidectomy / Efeitos da reconstrução da cavidade da timpanomastoidectomia com técnica aberta na morbidade e qualidade de vida

Abstract Introduction: Canal wall down tympanomastoidectomy is commonly used to treat advanced chronic otitis media or cholesteatoma. The advantages of canal wall down mastoidectomy are excellent exposure for disease eradication and postoperative control of residual disease; its disadvantages include the accumulation of debris requiring life-long otological maintenance and cleaning, continuous ear drainage, fungal cavity infections, and the occurrence of dizziness and vertigo by changing temperature or pressure. Objective: To evaluate whether cavity-induced problems can be eliminated and patient comfort can be increased with mastoid cavity reconstruction. Methods: In total, 11 patients who underwent mastoid cavity reconstruction between March 2013 and June 2013 comprised the study group, and 11 patients who had dry, epithelialized CWD cavities were recruited as the control group. The study examined three parameters: epithelial migration, air caloric testing, and the Glasgow Benefit Inventory. Epithelial migration, air caloric testing, and the Glasgow Benefit Inventory were evaluated in the study and control groups. Results: The epithelial migration rate was significantly faster in study group (1.63 ± 0.5 mm/week) than control group (0.94 ± 0.37 mm/week) (p = 0.003, p < 0.05). The mean slow component velocity of nystagmus of the study group (13.33 ± 5.36°/s) was significantly lower when compared to control group (32.11 ± 9.12°/s) (p = 0.018). The overall the Glasgow Benefit Inventory score was −7.21, and the general subscale, physical and social health scores were −9.71, −21.09, and +20.35, respectively in the control group. These were +33.93, +35.59, +33.31, and +29.61, respectively in the study group. All but the social health score improved significantly (0.007, 0.008, 0.018, and 0.181, respectively). Conclusions: Cavity reconstruction improves epithelial migration, normalizes caloric responses and increases the quality of life. Thus, cavity rehabilitation eliminates open-cavity-induced problems by restoring the functional anatomy of the ear.

Resumo Introdução: A timpanomastoidectomia com a técnica Canal Wall Down, ou técnica aberta, é comumente utilizada para tratar otite média crônica avançada ou colesteatoma. As vantagens da mastoidectomia pela técnica aberta são uma excelente exposição para a erradicação da doença e controle pós-operatório da doença residual; suas desvantagens incluem o acúmulo de detritos que requerem manutenção e limpeza otológica ao longo da vida, drenagem contínua da orelha, infecções fúngicas na cavidade e a ocorrência de tonturas e vertigem com alterações de temperatura ou pressão. Objetivo: Avaliar se os problemas induzidos pela cavidade podem ser eliminados e o conforto do paciente aumentado com a reconstrução da cavidade mastoide. Método: No total, 11 pacientes submetidos à reconstrução da cavidade mastoide entre março de 2013 e junho de 2013 constituíram o grupo de estudo, e 11 pacientes com cavidades secas e epitelizadas, operadas pela técnica aberta, foram recrutados como grupo controle. O estudo analisou três parâmetros: migração epitelial, prova calórica com estimulação a ar e o questionário Glasgow Benefit Inventory. A migração epitelial, a prova calórica e o Glasgow Benefit Inventory foram avaliados nos grupos de estudo e controle. Resultados: A taxa de migração epitelial foi significativamente mais rápida no grupo de estudo (1,63 ± 0,5 mm/semana) do que no grupo controle (0,94 ± 0,37 mm/semana) (p = 0,003, p < 0,05). A velocidade média do componente lento do nistagmo no grupo de estudo (13,33 ± 5,36°/s) foi significativamente menor se comparada ao grupo controle (32,11 ± 9,12°/s) (p = 0,018). O escore global do Glasgow Benefit Inventory foi de -7,21 e os escores da subescala geral, saúde física e social foram -9,71, -21,09 e +20,35, respectivamente, no grupo controle. Esses escores foram +33,93, +35,59, +33,31 e +29,61, respectivamente, no grupo de estudo. Todos, exceto o escore de saúde social, melhoraram significativamente (0,007, 0,008, 0,018 e 0,181, respectivamente). Conclusões: A reconstrução da cavidade melhora a migração epitelial, normaliza as respostas da prova calórica e aumenta a qualidade de vida. Assim, a reabilitação da cavidade elimina os problemas induzidos por cavidades abertas ao restaurar a anatomia funcional da orelha.

Audiovestibular Loss of Function Correlates in Vestibular Schwannomas.

OBJECTIVES: The aim of the present study was to investigate the relationships between tumor size, hearing, and vestibular outcomes in patients with vestibular schwannomas (VSs). MATERIALS AND METHODS: Adult patients (n=124) with unilateral extrameatal VS prior to surgery were included in the study. This was a retrospective cohort study of preoperative audiovestibular investigations including audiometry, discrimination test, caloric test, cervical vestibular evoked myogenic potential (c-VEMP), and ocular vestibular evoked myogenic potential (o-VEMP). RESULTS: The difference between lesioned and non-lesioned ear was significant for all audiovestibular outcomes. The mean caloric deficit was 74%. No tumor sided o-VEMPs were elicited. Caloric deficit correlated with hearing loss measured with pure tone average and discrimination score. c-VEMP deficit was significantly associated with severe hearing loss and larger tumors. CONCLUSION: The presence of VS leads to a significant deterioration of audiovestibular function in all objective measures. Caloric test and o-VEMPS are sensitive though unspecific measures of VSs. Increasing tumor size is not directly associated with hearing loss and only somewhat to vestibular deficit. However, audiovestibular findings are correlated.

Repeated Attacks of Dizziness Caused by a Rare Mitochondrial Encephalomyopathy.

Cases of dizziness caused by multiple sclerosis are commonly reported, but those caused by mitochondrial encephalomyopathy have been rarely reported. Particularly, the description of eye nystagmography (ENG) using caloric and optokinetic nystagmus tests has not been reported to date. We encountered the case of a 40-year-old woman with mitochondrial encephalomyopathy who visited us with the chief complaint of dizziness. At first, we considered multiple sclerosis based on the magnetic resonance imaging (MRI) findings and dizziness. Repeated attacks of dizziness and serum lactic acid levels suggested mitochondrial encephalomyopathy. A muscle biopsy confirmed the diagnosis. ENG findings suggested central vestibular disorder of the cerebellum and brainstem. This case suggests that we should not rule out the differential diagnosis of a very rare mitochondrial encephalomyopathy in patients who experience dizziness with MRI findings indicative of multiple sclerosis.

Effects of cavity reconstruction on morbidity and quality of life after canal wall down tympanomastoidectomy.

INTRODUCTION: Canal wall down tympanomastoidectomy is commonly used to treat advanced chronic otitis media or cholesteatoma. The advantages of canal wall down mastoidectomy are excellent exposure for disease eradication and postoperative control of residual disease; its disadvantages include the accumulation of debris requiring life-long otological maintenance and cleaning, continuous ear drainage, fungal cavity infections, and the occurrence of dizziness and vertigo by changing temperature or pressure. OBJECTIVE: To evaluate whether cavity-induced problems can be eliminated and patient comfort can be increased with mastoid cavity reconstruction. METHODS: In total, 11 patients who underwent mastoid cavity reconstruction between March 2013 and June 2013 comprised the study group, and 11 patients who had dry, epithelialized CWD cavities were recruited as the control group. The study examined three parameters: epithelial migration, air caloric testing, and the Glasgow Benefit Inventory. Epithelial migration, air caloric testing, and the Glasgow Benefit Inventory were evaluated in the study and control groups. RESULTS: The epithelial migration rate was significantly faster in study group (1.63±0.5mm/week) than control group (0.94±0.37mm/week) (p=0.003, p<0.05). The mean slow component velocity of nystagmus of the study group (13.33±5.36°/s) was significantly lower when compared to control group (32.11±9.12°/s) (p=0.018). The overall the Glasgow Benefit Inventory score was -7.21, and the general subscale, physical and social health scores were -9.71, -21.09, and +20.35, respectively in the control group. These were +33.93, +35.59, +33.31, and +29.61, respectively in the study group. All but the social health score improved significantly (0.007, 0.008, 0.018, and 0.181, respectively). CONCLUSIONS: Cavity reconstruction improves epithelial migration, normalizes caloric responses and increases the quality of life. Thus, cavity rehabilitation eliminates open-cavity-induced problems by restoring the functional anatomy of the ear.

Sensitivity of caloric test and video head impulse as screening test for chronic vestibular complaints.

OBJECTIVE:: This study compared the results of the caloric test with those of the video head impulse test obtained during the same session and evaluated whether the former can be used to screen for non-acute vestibular dysfunction. METHODS:: A total of 157 participants complaining of dizziness with vestibular characteristics of varying durations and clinical courses completed the caloric test and video head impulse test. RESULTS:: Significantly more caloric test results than video head impulse test results were abnormal. CONCLUSIONS:: The results of the caloric test and video head impulse test are distinct but complement each other. Within our sample, the caloric test was more sensitive for vestibular dysfunction. Therefore, the video head impulse test is not a suitable screening tool of the vestibular system in patients with chronic complaints.

Sensitivity of caloric test and video head impulse as screening test for chronic vestibular complaints

OBJECTIVE: This study compared the results of the caloric test with those of the video head impulse test obtained during the same session and evaluated whether the former can be used to screen for non-acute vestibular dysfunction. METHODS: A total of 157 participants complaining of dizziness with vestibular characteristics of varying durations and clinical courses completed the caloric test and video head impulse test. RESULTS: Significantly more caloric test results than video head impulse test results were abnormal. CONCLUSIONS: The results of the caloric test and video head impulse test are distinct but complement each other. Within our sample, the caloric test was more sensitive for vestibular dysfunction. Therefore, the video head impulse test is not a suitable screening tool of the vestibular system in patients with chronic complaints.

Efficacy of steroid therapy based on symptomatic and functional improvement in patients with vestibular neuritis: a prospective randomized controlled trial.

The aim of this study was to examine the efficacy of methylprednisolone in vestibular neuritis (VN) by objective and subjective measures. This prospective controlled randomized study was conducted at one tertiary hospital. Twenty-nine VN patients were randomized to either the steroid (n = 15) or the control (n = 14) group. The steroid group received methylprednisolone for 2 weeks, whereas control patients did not; both groups underwent regular vestibular exercises and were prescribed a Ginkgo biloba. Vestibular function tests including caloric test, video head impulse test (vHIT), and sensory organization test (SOT) were performed, and dizziness handicap index (DHI) was determined at enrollment; all tests were repeated at 1 and 6 months after enrollment. Both groups showed statistically significant improvements in caloric weakness and vHIT gain at 1- and 6-month follow-up evaluations compared to the initial examination; however, differences were not significant. The rates of normalization of canal paresis at 1 and 6 months were 50 and 64% in the control group and 33 and 60% in the steroid group, respectively, with no differences between the two groups. The rates of vHIT normalization at 1 and 6 months after treatment were 57 and 78% in the control group and 53 and 87% in the steroid group, respectively, with no differences between the two groups. Finally, there were no significant differences in the improvement of composite scores of SOT and the DHI scores between the two groups. In this prospective RCT, methylprednisolone had no additional benefit in patients with VN who underwent vestibular exercises and received a Ginkgo biloba. TRIAL REGISTRATION: Clinicaltrials.gov Identifier, NCT02098330; Trial title, The Efficacy of Steroid Therapy in Vestibular Neuritis.

Correlation of Objective Audiometric and Caloric Function in Ménière's Disease.

Objective Ménière's disease affects the vestibular and audiologic systems; however, little is known about the relationship between audiometric and caloric function with increasing duration of disease. We employed a novel methodology to understand the longitudinal correlation between audiometric and caloric function in Ménière's patients. Study Design Case series with chart review. Setting Neuro-otologic tertiary care practice. Subjects and Methods Charts of 19 patients with unilateral Ménière's disease, as classified by the 1995 American Academy of Otolaryngology-Head and Neck Foundation criteria, were examined. We included patients with ≥2 videonystagmograms and audiograms. We excluded those with bilateral Ménière's, prior audiovestibular destruction, or symptoms suggesting concomitant vestibular pathology. Spearman's rank correlation of audiometric status (pure tone average [PTA], low PTA, and word recognition score [WRS]) and vestibular function (bithermal calorics) was performed. The study was Institutional Review Board approved (protocol 2015H0266). Results A total of 112 audiograms and 42 videonystagmographies were performed. There was a decline in affected ear hearing PTA and WRS with duration of disease ( r = 0.602, P < .001, and r = -0.573, P < .001, respectively). Similarly, there was a decline in vestibular function with increasing duration of disease ( r = 0.709, P < .001). There were moderate correlations between vestibular weakness and PTA, low PTA, and WRS ( r = 0.464, P = .002; r = 0.498, P = .001; and r = -0.518, P = .001, respectively). Conclusions There is a correlation between decline in objective hearing and horizontal semicircular canal function with time. As expected, this correlation is not 1:1, indicating differential involvement of both systems. Understanding this relationship may assist in counseling patients with regard to prognosis, natural history, and therapeutic interventions.

Behavioural improvement in a minimally conscious state after caloric vestibular stimulation: evidence from two single case studies.

OBJECTIVE: To investigate whether caloric vestibular stimulation, a non-invasive form of neuro-modulation, alters the level of awareness in people residing in a minimally conscious state. DESIGN: Single-case ( n = 2), prospective, controlled (ABAB) efficacy study. SETTING: Tertiary, neuro-rehabilitation inpatient ward within a university hospital. PARTICIPANTS: Two individuals in a minimally conscious state. INTERVENTION: Left ear caloric vestibular stimulation was performed in two four/five-week blocks interleaved with two four/five-week blocks of sham stimulation. Session duration and frequency gradually increased within each block from once per day for 10 minutes (Week 1) to once per day for 20 minutes (Week 2) to 20 minutes twice per day in the remaining weeks. MEASURES: Wessex Head Injury Matrix, JFK Coma Recovery Scale - Revised. RESULTS: Both participants' Wessex Head Injury Matrix scores indicated a transition from involuntary (i.e. mechanical vocalization) to voluntary (i.e. gesture making, selective responses to family members) behaviour that was time-locked to the onset of active stimulation. In one participant, this improvement persisted for at least four weeks after active stimulation, while in the other it diminished two weeks after stimulation. Allied, although less dramatic, changes were seen on the arousal and auditory subscales of the JFK Coma Recovery Scale - Revised. CONCLUSION: The data provide the first evidence that vestibular stimulation may help improve outcome in a low awareness state, although further studies are needed to replicate effect and determine longer-term benefit.

Anatomic Variations in Temporal Bones Affect the Intensity of Nystagmus During Warm Caloric Irrigation.

HYPOTHESIS: Anatomic variables within the mastoid will correlate with intensity of caloric responses. BACKGROUND: During caloric irrigation, heat is transferred from the external auditory canal to the lateral semicircular canal (LSCC) through aerated mastoid bone. Temporal bone airspace volume and bone volume vary widely but the effect of this variation on caloric irrigation testing is not well characterized. Understanding this effect is necessary to understand how mastoid surgery may alter caloric irrigation results. METHODS: Twenty-two mastoid airspace and bones, as well as LSCC, were reconstructed from computed tomography scans of 11 subjects with normal anatomy who underwent vestibular function evaluation. Respective surface area (SA) and volume (V) of the mastoid airspace, bones, LSCC, and distance from LSCC to tympanic membrane (LSCC-TM) were calculated. In addition, computed values from these anatomic structures were correlated with the maximum velocity of slow phase nystagmus during warm caloric irrigation (MVwarm). RESULTS: Our results showed that the combined effect of airspace SA:V, bone SA:V, LSCC SA:V, and LSCC-TM distance accounted for 69.5% of the variation in MVwarm. Airspace SA:V (R = 0.22) and LSCC SA:V (R2 = 0.02) positively correlated with MVwarm, while bone SA:V (R = 0.17) demonstrated an inverse correlation with MVwarm. CONCLUSION: Preliminary results from this pilot study suggest that a substantial amount of the variability in MVwarm can be explained by temporal bone anatomy. Results also indicate that the denser the bone, the more heat is transferred to the LSSC, whereas increased airspace serves as an insulator. A larger study is necessary to confirm our findings.

Monothermal Caloric Screening to Improve Healthcare Value.

OBJECTIVES: To evaluate whether monothermal caloric screening can reduce the number of caloric irrigations required in the vestibular testing battery while maintaining diagnostic accuracy. DESIGN: Prospective controlled cohort study. Three hundred and ninety patients referred for vestibular testing at this tertiary referral health system over a 1-year period were evaluated; 24 patients met exclusion or failure criteria and 366 patients were included in the study. Population was 35.6% male; average age was 50.4 years old. Each patient underwent caloric testing using either warm or cool water irrigation initially and this data was used for monothermal screening data. All patients then completed bithermal binaural caloric testing to obtain the "gold standard" bithermal data for comparison. The sensitivity and specificity of monothermal cool or monothermal warm caloric tests were calculated using a receiver operating characteristic curve analysis. RESULTS: Using a monothermal interear difference threshold of 25%, warm monothermal screening had sensitivity of 98.0%, specificity of 91.3%, false negative rate of 2%, and false positive rate of 8.7%. Cool monothermal screening also had excellent sensitivity (92.3%) and specificity (95.3)%, with a false negative rate of 7.7%, and a false positive rate of 4.7%. The diagnosis associated with the single false negative warm monothermal caloric test was compensated vestibular paresis. In the study population, 71.9% had a negative monothermal screen; if the monothermal data were accepted, 2 fewer irrigations would have been performed resulting in an average saving of $264 (typical Medicare reimbursement for 2 irrigations) billed per patient screened as well as shortening the average testing battery by about 15 min. CONCLUSIONS: Warm monothermal caloric screening can reduce time and cost of vestibular testing while nearly matching the diagnostic accuracy of bithermal testing.

The effects of abnormality of cVEMP and oVEMP on rehabilitation outcomes in patients with idiopathic benign paroxysmal positional vertigo.

The presence of utricular and saccular dysfunction impairs quality of life (QoL) in patients. The aims of the present study were to examine the effect of repositioning maneuvers on QoL of patients with idiopathic benign paroxysmal positional vertigo (BPPV) and to describe the effect of cervical vestibular-evoked myogenic potential (cVEMP) or ocular VEMP (oVEMP) abnormalities on patient recovery after rehabilitation. Thirty idiopathic BPPV patients with/without otolith dysfunctions (n = 15, each group) were included in this clinical trial study. Otolith dysfunction was determined using oVEMP and cVEMP abnormalities. EcochG and caloric tests were performed to rule out other causes of secondary BPPV. The QoL in groups of patients with idiopathic BPPV was assessed using a Persian version of the dizziness handicap inventory (DHI-P) before and after treatment with Epley's maneuver. Pre-treatment results showed significant handicaps in both groups. DHI-P scores were higher in BPPV patients with otolith dysfunction (total, functional, emotional, physical score: 34.13, 11.20, 7.06, 15.86, respectively) than those in patients without otolith dysfunction (total, functional, emotional, physical score: 25.46, 7.86, 6.13, 11.46, respectively, P < 0.05). After treatment, DHI-P scores decreased in both groups. However, in the otolith dysfunction group, DHI-P scores (total, functional, emotional, physical score: 9.20, 3.33, 1.33, 4.53, respectively) were higher than those in patients without otolith dysfunction (total, functional, emotional, physical score: 4.13, 0.93, 1.06, 2.00, respectively). In BPPV patients with cVEMP or oVEMP abnormalities, QoL is more compromised in comparison with that in BPPV patients without these dysfunctions. Otolith dysfunction enhances the negative effects of BPPV on QoL.

Evaluación del Video Head Impulse Test (V-Hit) en el diagnóstico del neurinoma del acústico / Evaluation of video Head Impulse Test (v-HIT) in the diagnosis of acoustic neuroma

Introducción: La gran mayoría de lesiones que comprometen el conducto auditivo interno corresponden a schwannomas vestibulares (90%). Dentro de las nuevas pruebas diagnósticas del sistema vestibular aparece la prueba de impulso cefálico y su registro con el video Head Impulse Test (v-HIT) que permite el estudio de todos los canales semicirculares. Objetivo: Comparar el v-HIT para canales semicirculares laterales con las pruebas calóricas clásicas registradas mediante videonistagmografía en el comportamiento de los neurinomas intracanaliculares y evaluar su utilidad como test diagnóstico. Material y método: Dieciocho pacientes fueron reclutados con diagnóstico de neurinomas, confirmado mediante resonancia magnética y estudios con pruebas calóricas clásicas y v-HIT para canal horizontal. Resultados: Los resultados anormales de asimetría de ganancia y de sacadas correctivas fue de 13 pacientes (72%) y con hipoexcitabilidad en la prueba calórica fue de 9 pacientes (50%), con una sensibilidad de la prueba de 72% para vHIT y de 50% para la prueba calórica al compararlo con la resonancia magnética. Conclusión: El v-HIT es una herramienta complementaria a las pruebas calóricas y debe ser incluida como test diagnóstico dentro de la batería de exámenes para evaluar el sistema vestibular en forma completa mediante un vestibulograma.

Introduction: The majority of injuries involving the internal auditory canal correspond to vestibular schwannomas (90%). Within the new diagnostic tests for the vestibular system appears the Head Impulse test and the video head impulse test (v-HIT) which allows the studying of all the semicircular canals. Aim: Compare the v-HIT lateral semicircular canals with classical caloric tests recorded by videonistagmography (VNG) in the behavior of intracanalicular neuroma and evaluate its usefulness as a diagnostic test. Material and method: Eigtheen patients were enrolled with a diagnosis of schwannomas, confirmed by MRI and studied classical caloric tests and v-HIT for horizontal channel. Results: Abnormal results of asymmetry gain and corrective saccades was 13 patients (72%) and hypoexcitability in the caloric test was 9 patients (50%), with a test sensitivity of 72% for vHIT and 50% for caloric test compared with MRI. Conclusions: The v-HIT is a complementary tool to caloric tests and should be included as a diagnostic test within the battery of tests to evaluate the vestibular system in complete form by vestibulogram.

Methods considerations for nystagmography.

OBJECTIVES: 1. To assess the reproducibility of eye movement velocity measurement using two methods: traditional electro-oculography (EOG) and infrared video-oculography (VOG) and, 2. Determine whether the normal values for unilateral weakness and bilateral reduction of caloric responses vary according to method employed. BACKGROUND: Vestibular testing frequently involves measurement of eye movements. EOG has been the standard method for decades, but VOG and other methods have recently become popular. The assumption has been that all methods measure eye movements equally and accurately but this assumption has not been validated. In this paper we examine this assumption. METHODS: Eye movements were recorded simultaneously with commercially available EOG and VOG methods to evaluate differences in results for nineteen normal subjects undergoing caloric tests with warm and cold water. Examination of the records permitted identification and simultaneous measurement of 840 nystagmus beats. RESULTS: EOG and VOG measurements were correlated but the correlation was not strong (Spearman rho = 0.529, p < 0.01). Eye velocities recorded by the VOG system were greater than that for the EOG system. The mean VOG/EOG ratio was 1.71. Normal values used at our centre were adjusted to accommodate the use of video technology to account for the differences in sensitivity between EOG and VOG methods. CONCLUSION: The traditional EOG-based normal value for bilateral reduction of caloric response, 30 degree per second (d/s) based on traditional EOG measurements should be revised to 50 d/s for modern VOG testing in our lab. Normal values for vestibular testing may need to be re-evaluated when new technology is introduced. Each lab should verify normal values for their own methods and equipment.