Clinical significance of posterior expansion of the utricular endolymphatic space.

BACKGROUND: Posterior expansion of the utricular endolymphatic space (ES) is a finding occasionally observed, and often occurs in bilateral ears. The clinical significance of posterior expansion of the utricular ES is not clear. OBJECTIVES: To investigate the clinical significance of posterior expansion of the utricular ES detected on magnetic resonance imaging (MRI). MATERIALS AND METHODS: Among 957 patients who underwent contrast-enhanced MRI to investigate the presence of endolymphatic hydrops (EH), clinical findings in cases with posterior expansion of the utricular ES were evaluated and the significance of their existence is considered. RESULTS: Posterior expansion of the utricular ES was detected in 30 ears from 20 cases (7 males, 13 females; mean age 48.7 years). The ears with posterior expansion had a significantly lower incidence of vestibular EH than those without, and this tendency was more prominent in cases in bilateral ears. Some cases with posterior expansion had vestibular symptoms and were diagnosed with Ménière's disease, although EH was not detected in their vestibules. CONCLUSION AND SIGNIFICANCE: Posterior expansion of the utricular ES was associated with Ménière's disease without vestibular EH. Posterior expansion of the utricular ES might not be associated with the formation of EH but may occur independently.

Improvement of vertigo symptoms and acoustic power absorbance in cases with endolymphatic hydrops.

Objective: The pathophysiology and symptoms underlying Meniere's disease (MD) manifest as endolymphatic hydrops (EH), potentially impacting acoustic power absorbance in vestibular EH. The longitudinal effects of middle ear pressure therapy (MEPT) and conservative therapies for EH by magnetic resonance imaging (MRI) and on acoustic power absorbance on wideband acoustic immittance (WAI) were evaluated, and their changes were compared with clinical symptoms. Methods: Eleven patients with definite MD or delayed endolymphatic hydrops (DEH), resistant to conservative therapies and who continued MEPT for 1 year, were included. Vertigo scores, hearing levels, acoustic power absorbance on WAI, and degrees of EH on 3-T MRI were evaluated and compared before and after the treatments. Results: One year after the start of MEPT, all cases showed symptomatic improvement in vertigo score; however, the degrees of EH showed no improvements except in one case. In the affected ears with EH, their absorbances on WAI improved, particularly at 1580-1905 or 2400-2953 Hz (p < .05). Conclusion: Alleviation of vestibular symptoms with the therapy of MD was not necessarily associated with improved EH. Vestibular symptoms could be related to the change in the impedance of inner ear pressure, which was proven by the normalization of acoustic power absorbance. Assessments of acoustic power absorbance may provide useful information for physiological conditions and causative factors of vertigo in ears with EH. Level of evidence: 4.

Evaluation of the Listening Environment of Bilateral Cochlear Implant Users through Data Logging: A Comparison of Bilateral Simultaneous and Sequential Implantation.

OBJECTIVE: To evaluate the listening conditions of bilateral cochlear implant (CI) users in their daily living environment. STUDY DESIGN: Retrospective study. SETTING: University hospital. PATIENTS: Thirty-one adult CI users 16 years or older; 18 underwent sequential surgery, and 13 underwent simultaneous surgery. Inclusion criteria included the availability of CI data logging features and a minimum duration of binaural use of 6 months. INTERVENTION: Retrospective analysis of data obtained from the automatic scene classifier data logging system. MAIN OUTCOME MEASURE: Comparison of data logging and maximum speech discrimination scores of the two surgery groups (sequential vs. simultaneous) to investigate the potential influence of these factors on the listening conditions of CI users. RESULTS: The maximum speech discrimination score of the second CI in the sequential group was significantly worse than that of any other CI in the sequential and simultaneous CI groups. Additionally, the longer the interval between surgeries, the more significant the difference in "time on air" between the first and the second CIs. The second CI in sequential CI surgery had a shorter "time on air" than the first or the bilateral simultaneous CIs; the second CI was also used more frequently in noisy and speech with background noise environments. CONCLUSIONS: A second CI may be more frequently used in challenging listening environments because of its binaural auditory effect, despite its lower speech discrimination performance. The timing of sequential implantation and the potential impact of binaural hearing should be considered when developing rehabilitation strategies for individuals with bilateral CIs.

Comparative Analysis of Cartilage Conduction Hearing Aid Users and Non-Users: An Investigative Study.

Clinical findings on cartilage conduction hearing aids (CCHAs) have gradually become clear; however, few reports include a large number of cases. This study included 91 ears from 69 patients who underwent CCHA fitting in our hospital. Their ears were divided into six groups (i.e., bilateral aural atresia or severe canal stenosis, unilateral aural atresia or severe canal stenosis, chronic otitis media or chronic otitis externa with otorrhea, sensorineural hearing loss, mixed hearing loss, and conductive hearing loss) according to their clinical diagnosis and type of hearing loss. Most clinical diagnoses were aural atresia or meatal stenosis (bilateral, 21.8%; unilateral, 39.6%). The purchase rate of CCHAs was higher in the closed-ear group (bilateral, 77.3%; unilateral, 62.5%). In the bilateral closed-ear group, air conduction thresholds at 1000, 2000, and 4000 Hz and aided thresholds with CCHAs at 4000 Hz were significantly lower in the purchase group than the non-purchase group. No significant difference was observed between the purchase and non-purchase groups in the unilateral closed-ear group. In the bilateral closed-ear group, air conduction thresholds and aided thresholds were associated with the purchase rate of CCHAs. In the unilateral closed-ear group, factors other than hearing might have affected the purchase rate of CCHAs.

Significance of an augmented response on cervical vestibular evoked myogenic potential testing in Meniere's disease.

The potential mechanism of augmented response on cervical vestibular evoked myogenic potential (cVEMP) testing and its decrease following treatment in a patient with Meniere's disease (MD) are discussed. Changes of static posturography and cVEMP testing before and after a glycerol drip in a 69-year-old man with unilateral MD, in which significant endolymphatic hydrops (EH) was confirmed on magnetic resonance imaging (MRI) on the diseased side, were evaluated. Values of total locus lengths, areas of postural sway, and their Romberg ratios were decreased after the glycerol drip. On cVEMP testing, the diseased ear demonstrated a 375% larger amplitude than the contralateral ear before treatment, but both ears showed almost the same responses after treatment. An augmented response on cVEMP testing and a decrease following treatment for MD reflect the diversity of clinical findings in MD. Responses on cVEMP testing may relate not only to the degree of EH, but also be due to abnormal acoustic energy absorbance transmitted into the saccule.

Presence of endolymphatic hydrops on listening difficulties in patients with normal hearing level.

BACKGROUND: Listening difficulties (LiD) present difficulties in listening and paying attention to spoken information despite normal pure tone audiometry. Endolymphatic hydrops (EH) is a common inner ear condition associated with Ménière's disease but may also be present in the asymptomatic ear. OBJECTIVES: Using magnetic resonance imaging, we investigated EH in patients with LiD and assessed whether the severity of EH was related to the results of auditory processing tests (APTs). MATERIALS AND METHODS: 111 patients with no abnormalities on pure tone audiometry, but displaying difficulties in listening, underwent evaluation through APTs and questionnaires. Upon obtaining informed consent, the inner ears of 20 consenting patients were evaluated utilizing a 3-Tesla magnetic resonance imaging. RESULTS: A higher percentage of patients diagnosed with LiD by APTs had significant EH in the cochlea and vestibule than in previously reported control cases. The percentage of correct answers in the speech-in-noise test was significantly lower in patients with than in those without significant EH. CONCLUSION AND SIGNIFICANCE: In this study, significant EH of the cochlea was associated with poor listening to noise. The presence of EH affects the functioning of the auditory processing system, even in ears that test normally on standard audiometric tests.

Impact of endolymphatic hydrops on DPOAE in subjects with normal to mild hearing loss.

Objective: The increased endolymph volume affects a shift in the organ of Corti and basilar membrane in ears with endolymphatic hydrops (EH), which might affect distortion-product otoacoustic emissions (DPOAE) by altering the operating point of the outer hair cells. We investigated how changes in DPOAE are related to the distribution site of EH. Study Design: Prospective study. Methods: Among 403 patients with hearing or vestibular symptoms who underwent contrast-enhanced magnetic resonance imaging (MRI) for the diagnosis of EH and subsequent DPOAE testing, subjects whose hearing levels on pure tone audiometry were ≤35 dB at all frequencies were included in this study. In patients with EH on MRI, the presence and amplitude of DPOAE were evaluated between groups with hearing levels of ≤25 dB at all frequencies versus hearing levels of >25 dB at one or more frequencies. Results: There were no differences in the distribution of EH between groups. The amplitude of DPOAE had no clear correlation with the presence of EH. However, in both groups, there was a significantly higher probability of the presence of a DPOAE response from 1001 to 6006 Hz in cases with EH in the cochlea. Conclusion: Among patients whose hearing levels were ≤35 dB at all frequencies, better responses on DPOAE testing were found in subjects with EH in the cochlea. Alteration of DPOAEs in the early stages of hearing impairment could indicate morphological changes in the inner ear with altered basilar membrane compliance due to EH. Level of Evidence: 4.

Labyrinthine calcification in ears with otitis media and antineutrophil cytoplasmic antibody-associated vasculitis (OMAAV): A report of two cases.

Otitis media with antineutrophil cytoplasmic antibody-associated vasculitis (OMAAV) has been proposed as a new type of otitis media. The hearing loss caused by OMAAV can be expected to improve with early detection and intervention, but if it continues to worsen and leads to deafness, it is challenging to recover the patient's hearing. When bilateral deafness occurs, cochlear implant (CI) surgery is the only way to improve hearing. Here, Case 1 showed unilateral cochlear calcification, and Case 2 showed bilateral cochlear calcification. In Case 1, CI surgery was performed on the ear lacking calcification, and in Case 2 it was performed on the ear with milder calcification. In Case 2, granulation was present from the tympanic space to the mastoid, the round window was closed, and the basal turn of the cochlea was narrowed. Such calcification of the cochlea caused by OMAAV has not been reported so far. It is essential to detect these changes by computed tomography scans at an early stage and to perform CI surgery at an appropriate time, because hearing improvements are not expected in patients who become deaf because of OMAAV.

17O-labeled water distribution in the human inner ear: Insights into lymphatic dynamics and vestibular function.

We evaluated the inner ear distribution of 17O-labeled saline administered to the human tympanic cavity. Magnetic resonance imaging was performed after intratympanic administration in five healthy volunteers and one patient with cochlear endolymphatic hydrops. In all volunteers, 17O-labeled water permeated the cochlear basal turn and vestibule at 30 min and disappeared gradually within 2-4 h. All participants experienced positional vertigo lasting a few hours to a few days. Visualization of 17O-labeled water distribution in the endolymphatic space of the posterior ampulla showed indistinct separation of endolymph and perilymph in the cochlea and most of the vestibule in all participants. Intralabyrinthine distribution of 17O-labeled water differed from that in previous reports of intratympanically administered gadolinium-based contrast agent. 17O-labeled water in the endolymphatic space may cause heavier endolymph and positional vertigo. These results of this study may add new insights for investigating the distribution and the effects of molecules in the inner ear after the intratympanic administration in living humans.

Pathological significance and classification of endolymphatic hydrops in otological disorders.

We summarize the presence of endolymphatic hydrops (EH) in otological disorders evaluated with magnetic resonance imaging (MRI) of temporal bones, and propose a classification of EH based on its pathological significance. A search of the literature published in English-language journals was performed using electronic databases, especially focusing on EH-related otological disorders. Clinical articles that contained the terms EH and contrast-MRI published from 2007 to the present, with relevant human temporal bone studies, were included. The following three main points are discussed based on the results in the relevant articles: i) otological disorders that present EH, ii) current grading for evaluation of EH on MRI, and iii) a proposed classification of EH based on its pathological significance. MRI evaluation revealed that EH exists extensively not only in ears with typical Meniere's disease (MD), but also in those with various other otological disorders. The etiological classification of EH helps to summarize ideas for determining the pathophysiology of otological disorders, while a therapeutic classification provides clues to their management. MRI evaluations of EH have led to breakthroughs in investigations of EH in otological disorders. Precise grading for evaluation and clarification of EH on MRI based on its pathological significance could provide keys to elucidating the pathophysiology of EH-related otological disorders.

Factors Influencing the Purchase Rate of Cartilage Conduction Hearing Aids.

BACKGROUND: Innovated hearing aids (HAs), termed cartilage conduction hearing aids (CC-HAs), show good performance in patients with closed ears and continuous otorrhea. However, factors other than the ear condition that influence the purchase rate of CC-HAs remain unclear. PURPOSE: To identify the factors that influence the purchase rate of CC-HAs. RESEARCH DESIGN: A correlational study. STUDY SAMPLE: A total of 249 patients were enrolled. DATA COLLECTION AND ANALYSIS: The patients' demographics, clinical characteristics, outcomes, and CC-HA transducer types were compared. The data were analyzed for six groups classified based on the ear condition. RESULTS: In the unilateral closed-ear group, the purchase cases were significantly younger than the nonpurchase cases (p < 0.05). Regarding the outcomes in the bilateral closed-ear group, the purchase cases showed significantly better-aided thresholds at 0.25 and 0.5 kHz than the nonpurchase cases. No significant differences in the functional gains and speech recognition scores were found between purchase and nonpurchase cases in all six groups. Regarding the transducer type, the continued-use rate of the simple transducer type was significantly lower in the bilateral chronic continuous otorrhea, bilateral open, and unilateral open groups. CONCLUSION: In the closed ears, no remarkable negative factors were found. Transducer type had a significant influence on the continued-use rate in the nonclosed ears including the ears with chronic continuous otorrhea, although the purchase rate of CC-HAs in the bilateral chronic continuous otorrhea group was comparable to the closed ears.

Evaluation of the blood-perilymph barrier in ears with endolymphatic hydrops.

BACKGROUND: Otological diseases including Meniere's disease (MD) involve endolymphatic hydrops (EH), which can be visualized by magnetic resonance imaging (MRI) with gadolinium contrast agents, but the temporal changes of contrast in the inner ear have not been evaluated. OBJECTIVES: We investigated the permeability of the blood-perilymph barrier (BPB) in ears with EH to evaluate the severity of the inner ear disturbances. MATERIALS AND METHODS: The study included 32 ears from 16 patients with EH or related diseases who underwent MRI. The permeability of the BPB was assessed by the signal-intensity ratio (SIR) at four-time points: before and at 10 min, 4 h, and 24 h after administration of gadolinium for assessing EH. RESULTS: Cochlear EH was found in 25 of the 32 ears, and vestibular EH in 11. The rate of EH was significantly higher in symptomatic ears; however, the existence of EH was not related to SIR values. Nevertheless, SIR values in the basal turn were significantly higher 4 and 24 h after injection of gadolinium in patients aged ≥50 years. CONCLUSION AND SIGNIFICANCE: Higher SIR values observed in older patients with EH indicate severe disturbances of the BPB in the cochlea, which may account for intractable inner ear disturbances in older patients.

Cartilage Conduction Hearing Aid Fitting in Clinical Practice.

BACKGROUND: Cartilage conduction hearing aids (CCHAs) were newly devised and spread fast in Japan since their launch in 2017. However, little knowledge is available for this new device. PURPOSE: The aim of this study was to establish the knowledge of CCHAs and suggest their indication. RESEARCH DESIGN: Correlational study. STUDY SAMPLE: A total 256 patients were registered. DATA COLLECTION AND ANALYSIS: The fitting of CCHAs was surveyed in nine institutions. The outcomes were assessed by audiometric tests. The patients were classified into seven groups, depending on the ear conditions. The clinical characteristics, assessment results, and purchase rates were compared among the groups. The assessment results of CCHAs were also compared with those of previously used hearing aids. RESULTS: Most patients who used CCHAs were classified into the bilateral closed (aural atresia or severe stenosis) ear (n = 65) or unilateral closed ear (n = 124) groups. The patients in these groups achieved good benefits that resulted in a high purchase rate. The bilateral continuous otorrhea group also supported a high purchase rate, although the benefits of CCHAs were not always excellent. In contrast, the purchase rate was poor in the patients who could use air conduction hearing aids (ACHAs) without absolute problems. As for using a CCHA as a contralateral routing of signals hearing aid, the benefits depended on the patients. CONCLUSIONS: CCHAs are considered as a great option not only to the patients with closed ears but also to those who had difficulties in ACHAs usage.

Dilatation of the Endolymphatic Space in the Ampulla of the Posterior Semicircular Canal: A New Clinical Finding Detected on Magnetic Resonance Imaging.

OBJECTIVES: To investigate the clinical features of ears with dilatation of the endolymphatic space in the ampulla of the posterior semicircular canal on magnetic resonance imaging. STUDY DESIGN: Retrospective study. SETTING: A university hospital. METHODS: This study included 1,842 ears from 934 patients who underwent 3-T magnetic resonance imaging with gadolinium to investigate the presence of endolymphatic hydrops. Age, sex distribution, hearing thresholds on pure-tone audiometry, and vestibular symptoms were compared between cases of unilateral and bilateral dilatation of the endolymphatic space in the ampulla of the posterior semicircular canal. RESULTS: Forty-eight ears (17 men and 14 women; mean age 49.9 yrs) showed dilatation of the endolymphatic space in the ampulla of the posterior semicircular canal. Age and the rate of chronic sensorineural hearing loss were significantly higher in the unilateral group (14 ears) than in the bilateral group (34 ears). The average hearing thresholds and rates of vestibular symptoms reported did not differ between unilateral and bilateral cases, but some patients showed positional nystagmus. CONCLUSIONS: Dilatation of the endolymphatic space in the ampulla was observed selectively in the posterior semicircular canal, though its pathogenesis was not clear. Such dilatation is not usually accompanied by vestibular endolymphatic hydrops, and it may be a cause of vertigo and dizziness.

Lesion-specific prognosis by magnetic resonance imaging in sudden sensorineural hearing loss.

BACKGROUND: High signals in the inner ear of idiopathic sudden sensorineural hearing loss (ISSNHL) on magnetic resonance imaging (MRI) have been reported, but no quantitative evaluation has yet been done. OBJECTIVES: To evaluate hearing outcomes and cochlear signal intensities on 3-T heavily T2-weighted three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (hT2W-3D-FLAIR) in patients with ISSNHL. MATERIALS AND METHODS: Twenty-nine patients with ISSNHL were included. Patients underwent hT2W-3D-FLAIR with intravenous gadolinium injection and pure tone audiometry (PTA) at initial visits and 3 months later. Signal intensity ratios (SIRs) were measured in the basal or apical-middle turns of the affected cochlea. A statistical analysis of relationships between SIRs and the average hearing levels (HLs) at low (125, 250, and 500 Hz) and high (2, 4, and 8 kHz) tone frequencies was performed. RESULTS: Hearing improvements at high-tone frequencies in ears with HLs ≥60 dB were significantly worse in those with high SIRs at the basal turns on pre-contrast images. Similarly, hearing improvements at low-tone frequencies in ears with HLs ≥60 dB were significantly worse in those with high SIRs at the apical-middle turns on post-contrast images. CONCLUSIONS AND SIGNIFICANCE: High SIRs on hT2W-3D-FLAIR indicate cochlear disturbances with severe ISSNHL and could provide lesion-specific prognostic information.

Cochlear implantation in patient with Charcot-Marie-Tooth disease.

Two patients with auditory neuropathy spectrum disorder (ANSD) considered to be associated with Charcot-Marie-Tooth (CMT) are reported. In case 1, a 23-year-old man presented with progressive bilateral sensorineural hearing loss (SNHL) from 10 years of age and was diagnosed with ANSD. He was later diagnosed with CMT by neurological testing. In case 2, a 16-year-old girl, the younger sister of the patient in case 1, presented with progressive SNHL with similar auditory findings since 6 years of age as those of her brother. Both cases underwent bilateral cochlear implantation. In case 1, the maximum discrimination score improved to 45% 24 months after the first side of cochlear implantation from 5% before the surgery. In case 2, the score was 5% 10 months after cochlear implant (CI) surgery from 0% before the surgery. CI treatment for CMT patients has been considered difficult because of both failure in synchronization of nerve conduction due to demyelination and axonal failure of the auditory nerve. Though slower progress compared to the average subset of patients receiving CI was seen, significant improvement was gradually observed in the present patients after bilateral cochlear implantations. CI is thus a viable option for rehabilitation of SNHL in CMT patients.

Significance of high signal intensity in the endolymphatic duct on magnetic resonance imaging in ears with otological disorders.

BACKGROUND: High signal intensity in the endolymphatic duct (ED) is occasionally observed on magnetic resonance imaging (MRI) in ears that have otological disorders. OBJECTIVE: The signal intensity (SI) in the ED on post-contrast MRI was investigated in subjects with various otological disorders, and the meaning of high SI in the ED was evaluated. MATERIAL AND METHODS: 392 patients with otological disorders and 21 controls without otological symptoms underwent 3 T MRI. The SIs of the ED and the cerebellum were measured, the SI ratio (SIR) was calculated, and ears with SIR ≥4 were identified. RESULTS: A high SIR was identified in the ED of 3.7% of ears affected by definite Meniere's disease (dMD), 100% of ears affected by large vestibular aqueduct syndrome (LVAS), and 7.1% of ears with no otological symptoms. On the whole, a significant relationship was found between the existence of vestibular or cochlear EH and the SIR in the ED. CONCLUSION: The MRI finding of high SI in the ED may indicate the mechanism of inner ear disturbances in ears with otological disorders, especially in those with LVAS, and it may suggest an underlying disorder in some ears in which otological symptoms are not apparent.