Unilateral Sensorineural Hearing Loss Patients Research Articles

High Prevalence of Cochlear Nerve Deficiency in Pediatric Patients With Cochlear Aperture Stenosis.

Cochlear nerve deficiency (CND) is a common radiologic finding among unilateral sensorineural hearing loss (USNHL) patients. It is generally detected with magnetic resonance imaging (MRI), which is associated with higher cost, less availability, and possible need for sedation. Therefore, identifying computed tomography (CT) findings, such as cochlear aperture stenosis (CAS), that can reliably predict CND is valuable. Our study aimed to determine the prevalence of CND in pediatric patients with CT-diagnosed CAS. Retrospective study. Tertiary care center. We included pediatric patients diagnosed with CAS on temporal bone CT and with available temporal bone MRI. For each patient, an otolaryngologist and a pediatric neuroradiologist measured the cochlear aperture width on CT to confirm CAS (cochlear aperture < 1.4 mm) and assessed the status of the cochlear nerve on MRI. Fifty-five patients, representing 65 ears, had CAS on CT measurement. Median cochlear aperture width in CAS ears was 0.70 mm (interquartilerange [IQR]: 0.40-1.05 mm) versus 2.00 mm in non-CAS ears (IQR: 1.80-2.30 mm, P < .001). CND was found in 98.5% (n = 64/65) of CAS ears, while a normal cochlear nerve was found in 1.5% (n = 1/65) of CAS ears. CND is highly prevalent among pediatric patients with CAS. This suggests that MRI may not be needed to assess for CND in USNHL patients with CAS, as initial CT may provide sufficient information to determine cochlear implant candidacy. We recommend thoughtful shared decision-making with parents of USNHL patients when determining whether to pursue MRI in the setting of a CAS diagnosis.

Etiology, Severity, Audiogram Type, and Device Usage in Patients with Unilateral Moderate to Profound Sensorineural Hearing Loss in Japan.

Few studies have reported on the etiology, severity, or device usage of unilateral sensorineural hearing loss (UHL) compared to bilateral hearing loss. Therefore, this study investigated the characteristics of UHL in adults and children. We performed a survey using questionnaires for secondary and tertiary otolaryngology institutions. We included 15,981 patients (1549 children and 14,432 adults) from 196 institutions with otolaryngology residency programs and 2844 patients (336 children and 2508 adults) from 27 institutions with board members of the Japan Audiology Society. The latter submitted audiological data. Among children, most diagnoses were made at age 0. Approximately half of them had profound hearing loss, and 37 children (2.2%) used hearing devices. Among adults, the number of cases increased with age, but decreased when people reached their 80s and 90s. More than half of them had moderate hearing loss. Sudden sensorineural hearing loss was the most common cause of UHL of all ages; 4.4% of UHL patients used hearing devices, and most of the device users (98.6%) selected a conventional hearing aid. Hearing aid use is limited in children and adults with UHL in Japan. There could be many candidates with UHL for intervention such as a cochlear implant.

The Impact of Unilateral Sensorineural Hearing Loss on Quality of Life of Sub-Himalayan Population.

Introduction Unilateral Sensorineural Hearing Loss (USNHL) is an age-old known entity. Patients with USNHL lack the merits of binaural hearing, i.e., temporal summation, sound localization, and speech recognition in a noisy environment. The lack of binaural hearing affects such individuals' quality of life (QOL). The present study is the most extensive Indian series related to QOL in USNHL patients. Objectives This study aims to assess the impact of USNHL on the QOL of patients in the state of Uttarakhand. Methods A cross-sectional study was carried out at a tertiary care center in Uttarakhand over a period of 18 months, from January 2018 to July 2019. A total of 115 patients with pure USNHL were evaluated using a validated questionnaire—Hearing Handicap Inventory for Adults-Hindi (HHIA-H). Results In our study, patients with higher HHIA-H scores were male, young adults (age group 18–30 years), students, and laborers. Most of our patients (64%) had significant handicaps, followed by moderate handicaps in 25%. However, no significant correlation of degree of handicap was seen with age, duration, and degree of hearing loss. Conclusion USNHL can lead to a significant handicap that can severely affect the emotional and social aspects of life. Thus, early diagnosis and rehabilitation are essential to prevent handicap and uplift QOL in patients with USNHL. This trial is registered with Clinical Trials Registry of India (CTRI reg. no. CTRI/2018/06/014396).

Spectrum of Handicap in Unilateral Sensorineural Hearing Loss.

Unilateral Sensorineural Hearing Loss (USNHL) can present with varying symptoms apart from hearing loss, such as dizziness and tinnitus. Impaired sound localization, inability to identify speech in noise and decreased temporal summation can significantly impair the daily activities of an individual. This along with dizziness and tinnitus affects the physical, mental and social health as well. The purpose of this study is to assess and correlate the spectrum of handicap faced by USNHL patients. Validated questionnaires were used to evaluate handicap in 42 USNHL patients due to hearing loss (Hearing Handicap Inventory for Adults-HHIA), dizziness (Dizziness Handicap Inventory-DHI) and tinnitus (Tinnitus Handicap Inventory-THI). These handicaps were then correlated with each other using Spearman's correlation coefficient. Statistically significant strong positive correlation of HHIA was seen with DHI (rho = 0.60, p ≤ 0.001) and THI (rho = 0.74, p ≤ 0.001). Similarly, strong positive correlation was seen between emotional subscales of HHIA and DHI (rho = 0.73, p ≤ 0.001). USNHL can lead to significant emotional and social handicap which is compounded in the presence of hearing loss, dizziness and tinnitus. These handicaps are strongly correlated to one another. Hence, a holistic approach is needed for USNHL rehabilitation. There exists a need to develop a comprehensive measure to assess and grade the handicap faced by these patients.

Correlation of cochlear aperture stenosis with cochlear nerve deficiency in congenital unilateral hearing loss and prognostic relevance for cochlear implantation

The use of neonatal hearing screening has enabled the identification of congenital unilateral sensorineural hearing loss (USNHL) immediately after birth, and today there are several intervention options available to minimize potential adverse effects of this disease, including cochlear implantation. This study aims to analyze the characteristics of the inner ear of a homogeneous group of congenital non-syndromic USNHL to highlight the features of the inner ear, which can help in clinical, surgical, and rehabilitative decision-making. A retrospective chart review was carried out at a tertiary referral center. Systematic diagnostic work-up and rigorous inclusion–exclusion criteria were applied to 126 children with unilateral hearing impairment, leading to a selection of 39 strictly congenital and non-syndromic USNHL cases, undergoing computed tomography (CT) and magnetic resonance (MR) imaging studies. The frequency and type of malformations of the inner ear in USNHL and unaffected contralateral ears were assessed, with an in-depth analysis of the deficiency of the cochlear nerve (CND), the internal auditory canal (IAC) and the cochlear aperture (CA). Inner ear anomalies were found in 18 out of 39 (46%) of the USNHL patients. In 1 subject, the anomalies were bilateral, and the CND resulted in the predominant identified defect (78% of our abnormal case series), frequently associated with CA stenosis. Only 3 out of 14 children with CND presented stenosis of the IAC. CND and CA stenosis (and to a much lesser extent IAC stenosis) are a frequent association within congenital and non-syndromic USNHL that could represent a distinct pathological entity affecting otherwise healthy infants. In the context of a diagnostic work-up, the evaluation with CT and MRI measurements should take place in a shared decision-making setting with thorough counseling. Both imaging techniques have proven useful in differentiating the cases that will most likely benefit from the cochlear implant, from those with potentially poor implant performance.

Speech and language outcomes in mild-moderate unilateral sensorineural hearing loss

ObjectiveThe impact of mild-moderate unilateral sensorineural hearing loss (USNHL) on speech and language delay (SLD) is not well established. Objectives included (1) determining SLD prevalence in patients with mild-moderate USNHL in comparison to prevalence in the general population and severe-profound USNHL patients and (2) examining speech, language, and auditory function testing (SLAT) results in USNHL patients. MethodsA retrospective chart review of pediatric patients with USNHL, classified using pure tone averages (PTA) into mild-moderate (PTA 21–60) and severe-profound (PTA ≥ 61) USNHL groups was conducted. Abnormal SLAT values defined SLD. Prevalence and association of SLD based on USNHL severity was calculated. Onesample binomial tests compared observed frequencies of SLD to reported values. ResultsForty-nine patients were identified with USNHL; 34 patients underwent SLAT. SLD frequency for mild-moderate USNHL was 25% (95% CI, 9–49%), higher than the general population rate (5.95%). No statistically significant difference was noted between SLD frequency in mild-moderate versus severe-profound USNHL. There were no significant correlations between SLAT measures and PTA thresholds. ConclusionThere was a statistically significant increase in SLD in mild-moderate USNHL compared to the general population. There were no correlations between SLAT measures and PTA thresholds. Children with USNHL need close monitoring of speech, language and auditory development and functioning. Studies with larger sample sizes will help delineate if these findings truly reflect results in children with USNHL.

Unilateral sensorineural hearing loss: A retrospective study

Background: This retrospective study was carried out to know the characteristics of patients suffering from unilateral sensorineural hearing loss (USNHL) (type and degree). Aims and Objectives: (1) To know the incidence of pure USNHL (other ear being normal) in patients complaining of HL. (2) To establish the type and degree of USNHL in patients. Materials and Methods: This study was conducted over a period of more than 1 year to find out the pattern of pure USNHL (other ear being normal) in the patients attending ear, nose, and throat outpatient department (OPD) with a complaint of HL. Pure tone audiometry data of 1800 cases between August 2014 and December 2015 with HL were analyzed for this study. Demographic characteristics were compared with types and degrees of unilateral sensorineural hearing impairment. Results: A total of 1800 OPD patients who had a complaint of HL and had undergone pure tone audigram (PTA) in a period of more than 1 year in the Department of Otorhinolaryngology and Head and Neck Surgery were studied. SNHL type was the highest with 802 cases (44.55%). Out of 802 cases of SNHL, 257 (32.05%) were USNHL - out of which, only 155 patients (60.31%) had pure USNHL with other ear being normal; this constituted the study group, i.e., 155 patients (8.6%) out of 1800. Age of patients ranged from 9 years to 76 years (mean age - 41.5 years). Male:female ratio was 1.31:1. Both ears were almost equally involved. The highest numbers of USNHL patients were seen in the age group of 31-40 years (23.87%). Most cases presented with mild (34.2%), followed by profound (31.6%) USNHL. Conclusion: Our study concluded that SNHL type is the most common type (44.55%) of hearing impairment among patients complaining of HL. The incidence of pure USNHL (i.e. other ear being normal) was 60.31% (155/257) cases of USNHL, 19.32% (155/802) cases of SNHL, and 8.6% (155/1800) cases of PTA performed on patients complaining of HL. Limited work has been published on incidence, characteristics, and causes of pure USNHL. Further studies and researches are required in the field of USNHL to know the incidence, functional and psychological impact, and treatment options.

Changes of the directional brain networks related with brain plasticity in patients with long-term unilateral sensorineural hearing loss

Previous studies often report that early auditory deprivation or congenital deafness contributes to cross-modal reorganization in the auditory-deprived cortex, and this cross-modal reorganization limits clinical benefit from cochlear prosthetics. However, there are inconsistencies among study results on cortical reorganization in those subjects with long-term unilateral sensorineural hearing loss (USNHL). It is also unclear whether there exists a similar cross-modal plasticity of the auditory cortex for acquired monaural deafness and early or congenital deafness. To address this issue, we constructed the directional brain functional networks based on entropy connectivity of resting-state functional MRI and researched changes of the networks. Thirty-four long-term USNHL individuals and seventeen normally hearing individuals participated in the test, and all USNHL patients had acquired deafness. We found that certain brain regions of the sensorimotor and visual networks presented enhanced synchronous output entropy connectivity with the left primary auditory cortex in the left long-term USNHL individuals as compared with normally hearing individuals. Especially, the left USNHL showed more significant changes of entropy connectivity than the right USNHL. No significant plastic changes were observed in the right USNHL. Our results indicate that the left primary auditory cortex (non-auditory-deprived cortex) in patients with left USNHL has been reorganized by visual and sensorimotor modalities through cross-modal plasticity. Furthermore, the cross-modal reorganization also alters the directional brain functional networks. The auditory deprivation from the left or right side generates different influences on the human brain.

Bone-anchored hearing aids and unilateral sensorineural hearing loss: why do patients reject them?

This study aimed to report the bone-anchored hearing aid uptake and the reasons for their rejection by unilateral sensorineural deafness patients. A retrospective review of 90 consecutive unilateral sensorineural deafness patients referred to the Greater Manchester Bone-Anchored Hearing Aid Programme between September 2008 and August 2011 was performed. In all, 79 (87.8 per cent) were deemed audiologically suitable: 24 (30.3 per cent) eventually had a bone-anchored hearing aid implanted and 55 (69.6 per cent) patients declined. Of those who declined, 26 (47.3 per cent) cited perceived limited benefits, 18 (32.7 per cent) cited reservations regarding surgery, 13 (23.6 per cent) preferred a wireless contralateral routing of sound device and 12 (21.8 per cent) cited cosmetic reasons. In all, 32 (40.5 per cent) suitable patients eventually chose the wireless contralateral routing of sound device. The uptake rate was 30 per cent for audiologically suitable patients. Almost half of suitable patients did not perceive a sufficient benefit to proceed to device implantation and a significant proportion rejected it. It is therefore important that clinicians do not to rush to implant all unilateral sensorineural hearing loss patients with a bone-anchored hearing aid.

Aberrant topological properties of whole-brain functional network in chronic right-sided sensorineural hearing loss: a resting-state functional MRI study

To investigate the topological properties of the functional brain network in unilateral sensorineural hearing loss patients. In this study, we acquired resting-state BOLD- fMRI data from 19 right-sided SNHL patients and 31 healthy controls with normal hearing and constructed their whole brain functional networks. Two-sample two-tailed t-tests were performed to investigate group differences in topological parameters between the USNHL patients and the controls. Partial correlation analysis was conducted to determine the relationships between the network metrics and USNHL-related variables. Both USNHL patients and controls exhibited small-word architecture in their brain functional networks within the range 0. 1 - 0. 2 of sparsity. Compared to the controls, USNHL patients showed significant increase in characteristic path length and normalized characteristic path length, but significant decrease in global efficiency. Clustering coefficient, local efficiency and normalized clustering coefficient demonstrated no significant difference. Furthermore, USNHL patients exhibited no significant association between the altered network metrics and the duration of USNHL or the severity of hearing loss. Our results indicated the altered topological properties of whole brain functional networks in USNHL patients, which may help us to understand pathophysiologic mechanism of USNHL patients.

Functional Connectivity in Patients With Sensorineural Hearing Loss Using Resting-State MRI.

This study was undertaken to evaluate whole-brain functional connectivity changes related to auditory cortex in patients with left-sided sensorineural hearing loss (SNHL) using resting-state functional connectivity magnetic resonance imaging. Imaging was performed in 19 patients with left-sided SNHL and 35 individuals in the control group without SNHL. Data were collected and analyzed to map functional connectivity using the left/right primary auditory cortex as the region of interest to identify global differences between patients with SNHL and the control group. In comparison to the control group, the SNHL group was found to have significant functional connectivity changes in the auditory system, recognition network, visual cortex, and language network. These findings suggest that functional brain alterations in unilateral SNHL patients may indicate reorganizations that occur in response to auditory deficits.

Implication of Bony Cochlear Nerve Canal on Hearing in Patients with Congenital Unilateral Sensorineural Hearing Loss

This study was designed to evaluate the dimensions of the bony cochlear nerve canal (BCNC) in congenital unilateral sensorineural hearing loss (USNHL) patients with normal inner ears, and to analyze the correlation between BCNC and hearing status. Medical records and temporal bone computed tomography (TBCT) findings of 380 patients who visited Seoul National University Hospital between January 1999 and December 2007 were reviewed retrospectively. The length and width of the BCNC at the fundus of the internal auditory canal were measured in millimeters based on the axial view of TBCT for three ear groups: normal inner ears of control group subjects (group A, 179 ears), normal inner ears on the contralateral side of USNHL patients (group B, 201 ears), and the affected inner ears in USNHL (group C, 201 ears). The mean values of length and width in group C (0.79 ± 0.36 and 1.58 ± 0.83 mm, respectively) were significantly smaller than those in group A (1.07 ± 0.10 and 2.38 ± 0.28 mm, respectively; p < 0.001) and group B (1.04 ± 0.23 and 2.33 ± 0.39 mm, respectively; p < 0.001). The receiver operating characteristic curves for BCNC were conducted to estimate the cutoff values from which the proportions of profound hearing loss increased, compared to those of mild to severe hearing loss. The areas under the curve were 0.487 ± 0.044 (p = 0.781) and 0.622 ± 0.041 (p = 0.011) for length and width, respectively. The cutoff value of width with a sensitivity of 90% for profound USNHL was 1.16 mm in otherwise normal inner ears. Clinicians would be recommended to take a close look at BCNC as one of the possible causes of hearing loss in otherwise normal inner ears of USNHL on TBCT.

Functional MRI in normal subjects and sudden unilateral sensorineural hearing loss patients

Brain activities in responses to amplitude modulation (AM) was evaluated using functional MRI (fMRI) in subjects with sudden unilateral sensorineural hearing loss (SSNHL) and those with normal hearing (NH). Totally 25 subjects with normal hearing and 30 with SSNHL were examined with fMRI in response to AM tones of 500, 2000 and 4000 Hz respectively with the modulation frequency at 8 Hz. The fMRI was examined within 12 days after the onset of SSNHL. The AM signals were presented at 96 dB SPL binaurally. An event-related design was combined with a sparse clustered volume acquisitioning paradigm in data collection in the attempt to reduce the influence of acoustic scanner noise. SPM2 software was used for offline data analyzing. Brain activation in fMRI image was found mainly in the primary auditory cortex (PAC) in both subjects with NH and SSNHL NH subjects showed a clear lateralization to left cerebral hemisphere(11/16) and SSNHL patients showed a lateralization ipsilateral to the impaired ear(16/22). The activation voxel and intensity shown in BOLD were found to be decreased with increasing signal frequency in both groups. The difference in the lateralization between the two groups suggests that an adaptive process occurs shortly after the onset of SSNHL