Prevalence survey and psychometric measurement of vertigo and dizziness in individuals with obstructive sleep apnoea: A cross-sectional study.

INTRODUCTION: This study aimed to evaluate the prevalence and psychometric properties of vertigo and dizziness in an obstructive sleep apnoea (OSA) population. METHODS: Five hundred and twelve OSA patients and 53 controls were enroled. All eligible subjects were asked to complete the basic information questionnaire, the Chinese version of Vestibular Disorders Activities of Daily Living (VADL-C), the Dizziness Handicap Inventory (DHI) and the Activities-Specific Balance Confidence (ABC) scale. RESULTS: Among 512 enroled OSA patients, a 22.46% (115) prevalence of vertigo and dizziness was found. The scores of the VADL-C, DHI and ABC of the study group were significantly worse (p < .001) than those of the control group, while the abnormal rates of the three scales in the study group were higher than those of the control group. In the study group, the results of the VADL-C were correlated with those of the DHI (r = .55, p < .001) and inversely correlated with those of the ABC (r = -.50, p < .001), and the results of the DHI were inversely correlated with those of the ABC (r = -.60, p < .001). CONCLUSIONS: A high prevalence of vertigo and dizziness in the OSA population was detected. Psychometric results showed that vertigo and dizziness in OSA patients led to changes in activities of daily living, increased frequency of somatic symptoms, and reduced balance confidence. In the diagnosis and treatment of OSA patients, the occurrence of vertigo and dizziness is worth clinicians' attention.

The use of vestibular evoked myogenic potentials (VEMP) in the diagnosis of otolithic dysfunction of patients with obstructive sleep apnea: a survey of awareness and recognition of otorhinolaryngology medical staffs.

PURPOSE: To assess awareness and recognition of vestibular function tests in otorhinolaryngology medical staffs, especially the vestibular evoked myogenic potentials (VEMP) testing in patients with obstructive sleep apnea (OSA). METHODS: A survey was delivered via either email or a social media app. The medical staffs of the Chinese Medical Association of Otolaryngology Head and Neck Surgery from various branches were enrolled. Study data were collected and managed with an online data collection tool. RESULTS: A total of 1781 emails and 623 social media messages were sent to 2404 otorhinolaryngology medical staffs. One hundred and fifty-seven of them participated in the survey, including 24 via emails and 133 via the social media app. Regarding the knowledge of VEMP, only 59 (37.6%) of them agreed that OSA could be related to vertigo/dizziness/imbalance and 28 (17.8%) believed that OSA could result in VEMP abnormalities and would factor this in diagnosing the impairment of the vestibular function of OSA patients. A total of 7.6% of the respondents had never heard of the VEMP tests. Responses regarding the minimum age at which VEMP are possible ranged from younger than 6 months to greater than 18 years of age. Beliefs regarding the utility and reliability of VEMP varied, with 'unsure' being the most frequent response. In addition, only 17.8% of otolaryngologists indicated some access to the VEMP test. CONCLUSIONS: Knowledge and beliefs about the role of VEMP in diagnosing otolithic organ dysfunction caused by OSA in otorhinolaryngology vary widely. It is important for otorhinolaryngology medical staffs to learn the latest literatures and updated knowledge through continuing education.

The transcriptome characteristics of vestibular organs from delayed endolymphatic hydrops patients (Meniere's disease).

OBJECTIVES: To identify genes that are related to delayed endolymphatic hydrops (DEH) in patients by RNA-Seq analysis. DESIGN: Observational study. SETTING: Eye & ENT Hospital, Fudan University (Shanghai, China). PARTICIPANTS: We collected the entire vestibular system from four patients with DEH who underwent labyrinthectomy. Three control samples were collected from patients with acoustic neuroma or facial neuroma treated via the translabyrinthine approach. High-throughput RNA-Seq analysis was performed to investigate gene expression in the pathological vestibular system. MAIN OUTCOME MEASURES: Our bioinformatic analysis identified 17 genes that were upregulated and eight genes that were downregulated in patients with DEH compared with the controls. RESULTS: The altered gene expression profile suggested that DEH is closely related to neuropathy and autoimmune disease. In addition, many of the differentially regulated genes were involved in cell adhesion, suggesting a role of cell adhesion in DEH. Immunofluorescence analysis confirmed the expression of PMP2 and CLDN19 in the cytoplasm of hair cells and scattered expression of MPZ at cell junctions. The protein expression levels were higher in specimens from patients with Ménière's disease and DEH compared with controls. CONCLUSIONS: The protein expression profile of vestibular organs in patients with endolymphatic hydrops exhibited a degree of similarity to that of Ménière's disease. Endolymphatic hydrops is characterised by autoimmune abnormalities. DEH and Ménière's disease are likely to be different manifestations of the same disease, with disparate clinical symptoms. RNA-Seq is a useful analytical tool to characterise the vestibular pathology based on its transcriptome.

Effect of Endolymphatic Hydrops on Sound Transmission in Live Guinea Pigs Measured with a Laser Doppler Vibrometer.

Objective. This study aimed at describing the mechanism of hearing loss in low frequency and the different dynamic behavior of the umbo, the stapes head, and the round window membrane (RWM) between normal guinea pigs and those with endolymphatic hydrops (EH), using a laser Doppler vibrometer (LDV). Methods. Cochlear sections were stained with hematoxylin and eosin (HE) to evaluate the hydropic ratio (HR). Auditory brainstem responses (ABR) and whole-mount immunostaining were measured. Displacement of the umbo, stapes head, and RWM in response to ear-canal sound was evaluated using a LDV. Results. Mean HR values in EH model of all the turns are larger than the control group. The ABR threshold of the EH group was significantly higher than that of the control. Strong positive correlation was found between HR at apical turn and ABR threshold elevation at 1000 Hz and at subapical turn and ABR threshold elevation at 2000 Hz. FITC-phalloidin immunostaining of the cochlear basilar membrane in the apical, subapical, and suprabasal turns showed missing and derangement stereocilia of third-row outer hair cells. The umbo, stapes head, and RWM displacement in ears with EH was generally lower than that of normal ears. The EH-induced differences in stapes head and RWM motion were significant at 0.5 kHz. Conclusion. The LDV results suggested that the higher inner ear impedance in EH affected the dynamic behavior of the two opening windows of the cochlea and then reduced the vibration of the ossicular chain by increasing the afterload, resulting in acoustic dysfunction. The vibration reduction mainly occurred at low frequencies, which has related with the morphology changes of the apical and subapical turns in EH model.

A New Floating Piezoelectric Microphone for Fully Implantable Cochlear Implants in Middle Ear.

OBJECTIVE: Our team designed a long-lasting, well-sealed microphone, which uses laser welding and vacuum packaging technology. This study examined the sensitivity and effectiveness of this new floating piezoelectric microphone (NFPM) designed for totally implantable cochlear implants (TICIs) in animal experiments and intraoperative testing. METHODS: Different NFPM frequency responses from 0.25 to 10 kHz at 90 dB SPL were analyzed using in vivo testing of cats and human patients. The NFPM was tested in different positions that were clamped to the ossicular chains or placed in the tympanic cavity of cats and human patients. Two volunteers' long incus foot and four cats' malleus neck of the ossicular chain were clamped with the NSFM. The output electrical signals from different locations were recorded, analyzed, and compared. The NFPM was removed after the test without causing any damage to the middle-ear structure of the cats. Intraoperative tests of the NFPM were performed during the cochlear implant surgery and the cochlear implant surgery was completed after all tests. RESULTS: Compared with the results in the tympanic cavity, the NFPM could detect the vibration from the ossicular chain more sensitively in cat experiments and intraoperative testing. We also found that the signal output level of the NFPM decreased as the acoustic stimulation strength decreased in the intraoperative testing. CONCLUSION: The NFPM is effective in the intraoperative testing, making it feasible as an implantable middle-ear microphone for TICIs. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:937-944, 2024.

Chinese Version of the Vestibular Disorders Activities of Daily Living Scale.

OBJECTIVES/HYPOTHESIS: To translate and cross-culturally adapt vestibular disorders activities of daily living (VADL) scale to Chinese population, and verify its psychometric characteristics. STUDY DESIGN: A methodology study to translate, validate, and verify the reliability of the VADL scale. METHODS: The translation of the VADL from English to Chinese was carried out in accordance with the recommendations proposed by the Process of Cross-Cultural Adaptation guideline. All 185 Subjects with chief complaints of dizziness or vertigo were continuously invited to the study from January 2021 to June 2021. Investigation using the Chinese version of VADL (VADL-C) was completed by all the participants. Complete data from all 124 participants were used for reliability and internal consistency analysis by using SPSS 22.0. RESULTS: Through careful and complete translation and adaptation, the VADL-C was successfully created. The content validity of the VADL-C was 0.887, the internal consistency was 0.951, and the test-retest reliability was 0.989. CONCLUSIONS: The VADL-C has an excellent internal consistency, test-retest reliability, and content validity. It will be a new tool to be used in China and for overseas Chinese speakers to explore the functional capacity of individuals with vestibular diseases and guide therapy planning, particularly in vestibular rehabilitation training program. Laryngoscope, 132:1446-1451, 2022.

The correlation between the body shape and otolithic function in patients with obstructive sleep apnea.

OBJECTIVE: To identify the typical pattern of changes of vestibular-evoked myogenic potentials (VEMPs) and explore the relationship between VEMPs and the anthropometry factors in patients with obstructive sleep apnea (OSA). METHODS: Patients diagnosed as OSA after overnight polysomnography (PSG) tests were enrolled as the study group. Healthy volunteers were recruited as the control group. Anthropometry data of the body shape and VEMPs results were collected completely. The correlation analysis was conducted among those parameters. RESULTS: Forty-nine patients with OSA who were diagnosed in the Therapy Center of Sleep-disordered Breathing in our hospital and sex- and age-matched healthy controls as well. Significant changes in ocular and cervical VEMPs (oVEMP and cVEMP) in the study group were observed, which were reduced response rates, elevated thresholds, decreased amplitudes, and prolonged first wave latencies. In oVEMP, the first wave (n1) latency was significantly correlated with weight, body mass index (BMI), neck circumference, waist circumference, hip circumference, and apnea hypopnea index (AHI). In a tentative application, combined use of BMI and oVEMP n1 latency increased the detection rate during OSA screening prior to PSG. CONCLUSION: OSA can negatively affect function of otolithic organs and their pathways. The first wave latency of the VEMPs waveform may be another important parameter to define peripheral nervous system lesions caused by systemic diseases as OSA.

Uneven Effects of Sleep Apnea on Semicircular Canals and Otolithic Organs.

OBJECTIVE: This study aimed to explore how obstructive sleep apnea (OSA) affects the function of each vestibular organ and to identify the correlations among them. METHODS: A prospective study was conducted involving 32 healthy controls and 64 patients with OSA. The objective detection methods of the utricle and saccule are vestibular-evoked myogenic potentials (VEMPs). A combination of the caloric test and video head impulse test (vHIT) was used to comprehensively evaluate the objective function of semicircular canals. RESULTS: Elevated thresholds (p < 0.001), decreased waveform amplitudes (p < 0.001), prolonged first wave latencies (p < 0.001), and shortened first interpeak latencies (p < 0.001) were observed in both ocular VEMP (oVEMP) and cervical VEMP (cVEMP). A significant difference was found in the caloric test comparison (χ2 = 4.030, p = 0.045) but not in the vHIT. The intergroup comparison of normal rates among the VEMPs, caloric test, and vHIT groups showed a significant difference (p < 0.001). CONCLUSION: The impairment of vestibular function in patients with OSA was uneven and biased. More attention should be given to vestibular dysfunction in the diagnosis and treatment of OSA.

Vestibular dysfunction in pediatric patients with cochlear implantation: A systematic review and meta-analysis.

Objective: Vestibular dysfunction may delay the achievement of balance and perception milestones in pediatric patients after cochlear implantation (CIM). Methods: A strategic literature search was done following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched the PubMed, Medline, Embase, Web of Science, and Cochrane Library databases from inception to July 2022. Studies were included on the otoliths, semicircular canals, and balance function changes in children after CIM. Two reviewers independently assessed the level of evidence, methodological limitations, risk of bias, and characteristics of the cases. Matched pre- and postoperative vestibular functional test data, including ocular and cervical vestibular-evoked myogenic potential (oVEMP and cVEMP), caloric test, video head impulse test (vHIT), and Bruininks-Oseretsky Test 2 (BOT-2), were used to calculate the relative risk of vestibular disorders. Subgroup analyses were performed according to surgical approach, CIM device status, and etiology. Results: Twenty studies that met the inclusion criteria were selected for the meta-analysis. We observed significant vestibular dysfunction in pediatric patients with CIM. The results showed a statistically significant increase in abnormal cVEMP response (RR = 2.20, 95% CI = 1.87, 2.58, P < 0.0001), abnormal oVEMP response (RR = 2.10, 95% CI = 1.50, 2.94, P < 0.0001), and abnormal caloric test results (RR = 1.62, 95% CI = 1.20, 2.19, P = 0.0018) after implantation. Statistically significant differences were not found in the vHIT test results of all three semicircular canals before and after the operation (P > 0.05). Regarding static and dynamic balance, we found significantly poorer BOT-2 scores in children with CIM than in the normal group (mean difference = -7.26, 95% CI = -10.82, -3.70, P < 0.0001). Conclusion: The results showed that vestibular dysfunction might occur after CIM in pediatric patients. Some children experience difficulties with postural control and balance. Our results suggest that a comprehensive evaluation of vestibular function should be performed before and after CIM.

Evaluations on the stability and bio-compatibility of a new piezoelectric microphone for the implantable middle ear microphone.

BACKGROUND: A new floating piezoelectric microphone (NFPM), driven by the acoustic vibration of the ossicles, has been manufactured in the lab. OBJECTIVES: This study aimed at exploring the stability and bio-compatibility of this NFPM. MATERIALS AND METHODS: The NFPM was implanted into the cat tympanic cavity by clamping it to the handle of the malleus, and then a temporal bone computed tomography (CT) plain scan and three dimensional reconstruction were performed to observe its coupling with the handle of the malleus. After six months of implantation, cats' blood samples were taken for pro-inflammatory factor analysis. Then, the operative cavity was opened to check the NFPM, the auditory ossicular chain and some granulation tissue surrounding the NFPM. RESULTS: The NFPM was firmly clamped to the handle of the malleus of the cats during the six months of implantation. Besides, there was no obvious systemic inflammatory response in the experimental animals. In addition, local proliferation of granulation tissue occurred in the tympanic cavity without hampering the movement of the auditory ossicle,or causing ischemia of the auditory ossicle. CONCLUSION: The NFPM could be implanted in our experimental cats for a long period of time and had good bio-compatibility.

Characteristic manifestation of ocular and cervical vestibular evoked myogenic potentials findings in severe obstructive sleep apnea patients.

BACKGROUND: Studies of saccular and utricular function in patients with obstructive sleep apnea (OSA) are rare. We noticed that some OSA patients also had positive results in vestibular function tests, and this inspired our interest in exploring the vestibular function patterns of OSA patients. OBJECTIVES: To investigate otolithic organ function in severe OSA patients who lack vestibular symptoms and systemic disease. MATERIAL AND METHODS: 32 patients (64 ears) with severe OSA and 22 healthy controls (44 ears) were enrolled. The ocular and cervical vestibular-evoked myogenic potentials (oVEMP and cVEMP) and the caloric test were recorded and analyzed. RESULTS: The response rates of oVEMP (73.4%) and cVEMP (82.8%) in patients with severe OSA were significantly lower than those in controls. In oVEMP, elevated thresholds (p = .002), decreased n1-p1 amplitudes (p < .001), prolonged n1 latencies (p < .001) were observed. In cVEMP, the elevation of thresholds (p < .001), decrease in p1-n1 amplitudes (p < .001), and n1-p2 amplitudes (p < .001), prolongation of p1 latencies (p = .003) were observed. No significant difference in the caloric test was found between the two groups. CONCLUSIONS AND SIGNIFICANCE: Disappearance or impairment of VEMPs could be observed in patients with severe OSA, and reflects different degrees of impairment in the utricle and saccule.

Retro-labyrinthine Lesion Site Detected by Galvanic Vestibular Stimulation Elicited Vestibular-evoked Myogenic Potentials in Patients with Auditory Neuropathy.

OBJECTIVE: Auditory neuropathy (AN) is a unique pattern of hearing loss with preservation of hair cell function. The condition is characterized by the presence of otoacoustic emissions (OAE) or cochlear microphonic (CM) responses with severe abnormalities of the auditory brainstem response (ABR). The vestibular branches of the VIII cranial nerve and the structures innervated by it can also be affected. However, the precise lesion sites in the vestibular system are not well characterized in patients with AN. METHODS: The air-conducted sound (ACS) vestibular-evoked myogenic potentials (VEMPs) and galvanic vestibular stimuli (GVS)-VEMPs were examined in 14 patients with AN. RESULTS: On examination of VEMPs (n=14, 28 ears), the absent rates of ACS-cervical VEMP (cVEMP), ACS-ocular VEMP (oVEMP), GVS-cVEMP, GVS-oVEMP and caloric test were 92.9% (26/28), 85.7% (24/28), 67.9% (19/28), 53.6% (15/28), and 61.5% (8/13), respectively. Impaired functions of the saccule, inferior vestibular nerve, utricle, superior vestibular nerve, and horizontal semicircular canal were found in 25.0% (7/28), 67.9% (19/28), 32.1% (9/28), 53.6% (15/28) and 61.5% (8/13) patients, respectively. On comparing the elicited VEMPs parameters of AN patients with those of normal controls, both ACS-VEMPs and GVS-VEMPs showed abnormal results in AN patients (such as, lower presence rates, elevated thresholds, prolonged latencies, and decreased amplitudes). CONCLUSION: The study suggested that patients with AN often have concomitant vestibular disorders. Retro-labyrinthine lesions were more frequently observed in this study. GVS-VEMPs combined with ACS-VEMPs may help identify the lesion sites and facilitate detection of areas of vestibular dysfunction in these patients.

Different findings of morphological changes and functional decline in the vestibule and the semicircular canal in ipsilateral delayed endolymphatic hydrops.

OBJECTIVE: To elucidate the pathophysiological process by analyzing the correlation between morphological and functional changes in patients with delayed endolymphatic hydrops (DEH). METHODS: Twenty-nine patients diagnosed with DEH were enrolled in this retrospective study. All patients were assessed using the caloric test, cervical and ocular vestibular evoked myogenic potentials, and gadolinium-enhanced magnetic resonance imaging (MRI) of the inner ear. RESULTS: According to the MRI, the hydrops localization was categorized as hydrops in the vestibule (saccule and utricle) (14%), hydrops in the vestibule and cochlea (72%), and hydrops in the vestibule, cochlea, and lateral semicircular canal (LSCC) (14%). Vestibular hydrops could definitely be observed as function declined; however, a dysfunction of both the saccule and utricle was not always present when vestibular hydrops was detected with MRI. In the LSCC, a decline in functional tests was not necessarily accompanied by morphological abnormalities. However, dysfunction could definitely be detected when LSCC hydrops was observed with MRI. CONCLUSIONS: Hydrops can be found mainly in the vestibule as shown by MRI. In the vestibule, abnormalities are commonly morphologic rather than functional, whereas in the LSCC a functional deterioration can be detected more frequently than morphological changes. SIGNIFICANCE: Our findings can provide a new perspective on the functional and morphological characteristics of patients with DEH.

A new floating piezoelectric microphone for the implantable middle ear microphone in experimental studies.

CONCLUSIONS: The new floating piezoelectric microphone is feasible for use as an implantable middle ear microphone in a totally implantable cochlear implant. OBJECTIVES: A piezoelectric sensor that is driven by the acoustic vibration of the ossicles is one possible design for a microphone for a totally implantable cochlear implant. Such a new floating piezoelectric microphone has been manufactured in the lab. The purpose of this article was to study the frequency response of the new floating piezoelectric microphone in the intact ossicular chain and to identify whether it is usable and implantable. METHODS: The frequency response of the new floating piezoelectric microphone was analyzed using in vitro testing of fresh cadaveric heads. The microphone, which was designed with an integrated unibody structure to ensure good biocompatibility and capsulation, was attached to the long process of the incus by a titanium clip, or placed in the tympanic cavity and stimulated with pure tones of different frequencies. RESULTS: The new floating piezoelectric microphone can pick up the vibration of the long process of the incus and convert it into electrical signals sensitively and flatly.

The hidden dysfunction of otolithic organs in patients with profound sensorineural hearing loss.

OBJECTIVE: To define the profiles of ocular and cervical vestibular-evoked myogenic potentials (oVEMP and cVEMP, respectively) in patients with profound sensorineural hearing loss (PSHL). METHODS: Twenty-nine patients with PSHL and 20 healthy volunteers were investigated. The patients' medical records were collected and analyzed. The ACS-evoked oVEMPs and cVEMPs and caloric test were tested and analyzed. RESULTS: The oVEMP and cVEMP response rates in the patients with PSHL were 38.9% and 44.4%, respectively, and these values were significantly less than those in the healthy volunteers (both were 100%). Regarding the oVEMPs, significantly higher threshold (p < 0.001) and smaller amplitude (p = 0.022) were observed in the patients. Regarding the cVEMPs, a significant elevation in the threshold (p < 0.001) and a decrease in the amplitude (p = 0.024) were observed, and marked reductions in the P1 (p = 0.002) and N1 latencies (p = 0.001) were observed in the patients. Regarding the caloric test, the ratio of semicircular canal dysfunction in patients with PSHL was significantly higher than that in healthy volunteers (p < 0.001). However, neither the patients nor the doctors noticed balance problems or the loss of otolithic function in the summaries of the medical records of all 29 of the patients. CONCLUSION: The utricular and saccular dysfunction that can be concealed in patients with PSHL can be observed in oVEMPs and cVEMPs. Otolithic function should receive attention in the diagnosis and treatment of PSHL. VEMPs have special value for the observation of hidden dysfunctions of the otolithic organs of patients with PSHL.

Objective and subjective evaluations of the Nurotron Venus cochlear implant system via animal experiments and clinical trials.

CONCLUSION: This study described objective and subjective evaluations of the Nurotron® Venus™ Cochlear Implant System and indicated that this system produced a satisfactory performance. OBJECTIVE: To observe the performance of the Nurotron® Venus™ cochlear implant (CI) system via electrophysiological and psychophysical evaluations. METHODS: A 26-electrode CI system was specially designed. The performance of MRI in animal and cadaveric head experiments, EABR in cats experiment, the correlation between ESRT and C level, and psychophysics evaluations in clinical trials were observed. RESULTS: In the animal and cadaveric head experiments, magnet dislocation could not be prevented in the 1.5 T MRI without removal of the internal magnet. The EABR was clearly elicited in cat experiment. In the clinical trial, the ESRT was strongly correlated with C level (p < 0.001). The human clinical trial involving 57 post-lingually deafened native Mandarin-speaking patients was performed. Residual hearing protection in the implanted ear at each audiometric frequency was observed in 27.5-46.3% patients post-operatively. A pitch ranking test revealed that place pitches were generally ordered from apical to basal electrodes. The recognitions of the perceptions of 301 disyllabic words, environment sounds, disyllabic words, and numerals were significantly better than the pre-operative performance and reached plateaus.

Ocular and cervical vestibular-evoked myogenic potentials in children with cochlear implant.

OBJECTIVE: To define the profile of ocular and cervical vestibular-evoked myogenic potentials (oVEMPs and cVEMPs) in children with cochlear implant (CI), we studied air-conducted sound (ACS)-evoked responses pre- and postoperatively. METHODS: The ACS-evoked oVEMPs and cVEMPs of 31 children with cochlear implantation were investigated. Thresholds, amplitudes, P1 and N1 latencies, and interpeak latencies of VEMPs were measured and analyzed. RESULTS: Before CI, the response rates of oVEMPs and cVEMPs were 71.0% and 67.7%, respectively. The oVEMPs and cVEMPs on the operated side disappeared after CI, which resulted in a decrease in response rates, whether the device was switched on (12.9% and 32. 0%) or off (19.2% and 34.8%). In the case when VEMPs could be elicited on the operated side after CI, the parameters of waveforms showed abnormal changes, including threshold elevation (maximum of 8.34-dB SPL in oVEMP and 8.75-dB SPL in cVEMP) and amplitude decrease (maximum of 4.10µV in oVEMP and 191.82µV in cVEMP). CONCLUSIONS: Disappearance and impairment of VEMPs could be observed after CI, and the waveforms of oVEMP and cVEMP could reflect the degree of damage to the utricle and saccule caused by CI and other related factors. SIGNIFICANCE: The oVEMPs and cVEMPs prove to be accurate methods to evaluate vestibular function in children with CI.

The hidden loss of otolithic function in children with profound sensorineural hearing loss.

OBJECTIVE: This study sought to define the profile of ocular and cervical vestibular-evoked myogenic potential (oVEMP and cVEMP) in children with profound sensorineural hearing loss (PSHL). METHODS: The ACS-evoked oVEMPs and cVEMPs of 43 children with PSHL and 20 healthy children were investigated. The response rates, thresholds, amplitudes, P1 and N1 latencies, and interpeak latencies of VEMPs were analyzed. Each patient's medical record was summarized and classified. RESULTS: The response rates of oVEMP and cVEMP in patients with PSHL were 58.1% and 61.9% respectively, which were significantly less than those in healthy children (both were 100%). In the children patients whose oVEMP or cVEMP could still be elicited, significant elevated thresholds and decreased amplitudes in VEMPs could be observed (p<0.05). However, in the summary of the medical records of all the 43 patients, it was showed that neither the patients and their parents nor the doctors noticed the balance problem and the loss of otolithic function. CONCLUSIONS: The otolithic dysfunction, which could be easily ignored in children with PSHL, could be observed in VEMPs. In the process of diagnosis and treatment of PSHL, the vestibular function should obtain enough attention. VEMPs have special value in observation of the hidden loss of otolithic function, and could be an important vestibular assessment method for children with PSHL.

[Objective evaluation of otolithic end organs in sudden sensorineural hearing loss patients].

OBJECTIVE: To observe the function of the otolithic end organs and their input pathways in sudden sensorineural hearing loss (SSHL) patients. METHODS: Forty cases of unilateral SSHL were enrolled as the observing group from May, 2011 to May, 2012. Thirty age- and gender-matched normal subjects were recruited as the control group. Both patients and normal subjects underwent conventional air-conducted ocular vestibular evoked myogenic potential (oVEMP) and cervical vestibular evoked myogenic potential (cVEMP) in bilateral ears. The results were compared between the affected ears, the contralateral ears and the normal controls. RESULTS: Overall, oVEMP was elicited in 16 affected ears (40.0%), 23 contralateral ears (57.5%) and 43 normal ears (71.7%). cVEMP could be elicited in 25 affected ears (62.5%), 30 contralateral ears (75.0%) and 49 normal ears (81.7%) respectively. Significant statistical significance could be found in the oVEMP response rate between the affected ears and the normal ears (χ(2) = 9.949, P = 0.002) and in the cVEMP response rate between the affected ears and the normal ears (χ(2) = 4.582, P = 0.032). Significant statistical difference could not be found in all oVEMP and cVEMP parameters (threshold, N1 latency, P1 latency, latency interval and amplitude) among groups (P > 0.05). CONCLUSIONS: The otolithic vestibular end organs and their input pathways could be damaged in SSHL patients. Such damages could be monitored objectively by cVEMP and oVEMP examinations.