Bilateral, Sequential Sudden Hearing Loss in a Patient With Multiple COVID-19 Infections and Potential Implications on Subsequent Cochlear Implant Performance.

Viruses are often implicated as a cause of sensorineural hearing loss (SNHL), particularly sudden cases, including COVID-19. Determining the viral mechanism that leads to hearing loss is necessary for its future prevention and treatment. The 47-year-old woman who is the subject of this case study presented with sudden SNHL following multiple infections of COVID-19. Following a trial of a contralateral routing of sound device, she received a right cochlear implant (CI). Following a period of high performance, additional cases of COVID-19 infection and device failure issues resulted in the explant/reimplant of 1 ear and implantation of the contralateral ear. Despite extensive rehabilitation after these events, the patient continues to experience difficulties in speech understanding, not reaching her initial high levels of right ear performance. Further research is needed to determine the implications of COVID-19 as it relates to SNHL. This case study aimed to highlight the course of treatment and provide insight into the impact of COVID-19 on sudden hearing loss and its relationship to CI performance.

Evaluation of the Efficacy of a Dual Variable Speed Compressor over a Single Fixed Speed Compressor.

BACKGROUND: It has been suggested that hearing-impaired listeners with a good working memory (WM) should be fitted with a compression system using short time constants (i.e., fast-acting compression [FAC]), whereas those with a poorer WM should be fitted with a longer time constant (i.e., slow-acting compression [SAC]). However, commercial hearing aids (HAs) seldom use a fixed speed of compression. PURPOSE: The performance of a variable speed compression (VSC) system relative to a fixed speed compressor (FAC and SAC) on measures of speech intelligibility, recall, and subjective report of listening effort and tolerable time was evaluated. The potential interaction with the listeners' WM capacity (WMC) was also examined. RESEARCH DESIGN: A double-blinded, repeated measures design. STUDY SAMPLE: Seventeen HA wearers (16 with greater than one year HA experience) with a bilaterally symmetrical, mild to moderately severe sensorineural hearing loss participated in the study. DATA COLLECTION AND ANALYSIS: Participants wore the study HAs at three compression speeds (FAC, SAC, and VSC). Each listener was evaluated on the Office of Research in Clinical Amplification-nonsense syllable test (NST) at 50 dB SPL (signal-to-noise ratio [SNR] = +15 dB), 65 dB SPL (SNR = +5 dB), 80 dB SPL (SNR = 0 dB), and a split (80 dB SPL-50 dB SPL) condition. Listeners were also evaluated on a Repeat Recall Test (RRT), where they had to repeat six short sentences (both high- and low-context sentences) after each was presented. Listeners recalled target words in all six sentences after they were presented. They also rated their listening effort and the amount of time they would tolerate listening under the specific condition. RRT sentences were presented at 75 dB SPL in quiet, as well as SNR = 0, 5, 10, and 15 dB. A Reading Span Test (RST) was also administered to assess listeners' WMC. Analysis of variance using RST scores as a covariate was used to examine differences in listener performance among compressor speeds. RESULTS: Listener performance on the NST was similar among all three compression speeds at 50, 65, and 80 dB SPL. Performance with FAC was significantly better than SAC for the split condition; however, performance did not differ between FAC and VSC or between SAC and VSC. Performance on the NST was not affected by listeners' RST scores. On the RRT, there was no effect of compressor speed on measures of repeat, recall, listening effort, and tolerable time. However, VSC resulted in significantly lower (better) speech reception threshold at the 85% correct recognition criterion (SRT85) than FAC and SAC. Listener RST scores significantly affected recall performance on the RRT but did not affect SRT85, repeat, listening effort, or tolerable time. CONCLUSION: These results suggest that the VSC, FAC, and SAC yield similar performance in most but not all test conditions. FAC outperforms SAC, where the stimulus levels change abruptly (i.e., split condition). The VSC yields a lower SRT85 than a fixed compression speed at a moderately high level with a favorable SNR. There is no interaction between compression speed and the participants' WMC.

Tracking of Noise Tolerance to Predict Hearing Aid Satisfaction in Loud Noisy Environments.

BACKGROUND: A method that tracked tolerable noise level (TNL) over time while maintaining subjective speech intelligibility was reported previously. Although this method was reliable and efficacious as a research tool, its clinical efficacy and predictive ability of real-life hearing aid satisfaction were not measured. PURPOSE: The study evaluated an adaptive method to estimate TNL using slope and variance of tracked noise level as criteria in a clinical setting. The relationship between TNL and subjective hearing aid satisfaction in noisy environments was also investigated. RESEARCH DESIGN: A single-blinded, repeated-measures design. STUDY SAMPLE: Seventeen experienced hearing aid wearers with bilateral mild-to-moderately-severe sensorineural hearing loss. DATA COLLECTION AND ANALYSIS: Participants listened to 82-dB SPL continuous speech and tracked the background noise level that they could "put up with" while subjectively understanding >90% of the speech material. Two trials with each babble noise and continuous speech-shaped noise were measured in a single session. All four trials were completed aided using the participants' own hearing aids. The stimuli were presented in the sound field with speech from 0° and noise from the 180° azimuth. The instantaneous tolerable noise level was measured using a custom program and scored in two ways; the averaged TNL (aTNL) over the 2-min trial and the estimated TNL (eTNL) as soon as the listeners reached a stable noise estimate. Correlation between TNL and proportion of satisfied noisy environments was examined using the MarkeTrak questionnaire. RESULTS: All listeners completed the tracking of noise tolerance procedure within 2 min with good reliability. Sixty-five percent of the listeners yielded a stable noise estimate after 59.9 sec of actual test time. The eTNL for all trials was 78.6 dB SPL (standard deviation [SD] = 4.4 dB). The aTNL for all trials was 78.0 dB SPL (SD = 3.3 dB) after 120 sec. The aTNL was 79.2 dB SPL (SD = 5.4 dB) for babble noise and 77.0 dB SPL (SD = 5.9 dB) for speech-shaped noise. High within-session test-retest reliability was evident. The 95% confidence interval was 1.5 dB for babble noise and 2.8 dB for continuous speech-shaped noise. No significant correlation was measured between overall hearing aid satisfaction and the aTNL (ρ = 0.20 for both noises); however, a significant relationship between aTNL and proportion of satisfied noisy situations was evident (ρ = 0.48 for babble noise and ρ = 0.55 for speech-shaped noise). CONCLUSION: The eTNL scoring method yielded similar results as the aTNL method although requiring only half the time for 65% of the listeners. This time efficiency, along with its reliability and the potential relationship between TNL and hearing aid satisfaction in noisy listening situations suggests that this procedure may be a good clinical tool to evaluate whether specific features on a hearing aid would improve noise tolerance and predict wearer satisfaction with the selected hearing aid in real-life loud noisy situations. A larger sample of hearing aid wearers is needed to further validate these potential uses.

Tracking of Noise Tolerance to Measure Hearing Aid Benefit.

BACKGROUND: The benefits offered by noise reduction (NR) features on a hearing aid had been studied traditionally using test conditions that set the hearing aids into a stable state of performance. While adequate, this approach does not allow the differentiation of two NR algorithms that differ in their timing characteristics (i.e., activation and stabilization time). PURPOSE: The current study investigated a new method of measuring noise tolerance (Tracking of Noise Tolerance [TNT]) as a means to differentiate hearing aid technologies. The study determined the within-session and between-session reliability of the procedure. The benefits provided by various hearing aid conditions (aided, two NR algorithms, and a directional microphone algorithm) were measured using this procedure. Performance on normal-hearing listeners was also measured for referencing. RESEARCH DESIGN: A single-blinded, repeated-measures design was used. STUDY SAMPLE: Thirteen experienced hearing aid wearers with a bilaterally symmetrical (≤10 dB) mild-to-moderate sensorineural hearing loss participated in the study. In addition, seven normal-hearing listeners were tested in the unaided condition. DATA COLLECTION AND ANALYSIS: Participants tracked the noise level that met the criterion of tolerable noise level (TNL) in the presence of an 85 dB SPL continuous discourse passage. The test conditions included an unaided condition and an aided condition with combinations of NR and microphone modes within the UNIQUE hearing aid (omnidirectional microphone, no NR; omnidirectional microphone, NR; directional microphone, no NR; and directional microphone, NR) and the DREAM hearing aid (omnidirectional microphone, no NR; omnidirectional microphone, NR). Each tracking trial lasted 2 min for each hearing aid condition. Normal-hearing listeners tracked in the unaided condition only. Nine of the 13 hearing-impaired listeners returned after 3 mo for retesting in the unaided and aided conditions with the UNIQUE hearing aid. The individual TNL was estimated for each participant for all test conditions. The TNT index was calculated as the difference between 85 dB SPL and the TNL. RESULTS: The TNT index varied from 2.2 dB in the omnidirectional microphone, no NR condition to -4.4 dB in the directional microphone, NR on condition. Normal-hearing listeners reported a TNT index of -5.7 dB using this procedure. The averaged improvement in TNT offered by the NR algorithm on the UNIQUE varied from 2.1 dB when used with a directional microphone to 3.0 dB when used with the omnidirectional microphone. The time course of the NR algorithm was different between the UNIQUE and the DREAM hearing aids, with the UNIQUE reaching a stable TNL sooner than the DREAM. The averaged improvement in TNT index from the UNIQUE directional microphone was 3.6 dB when NR was activated and 4.4 dB when NR was deactivated. Together, directional microphone and NR resulted in a total TNT improvement of 6.5 dB. The test-retest reliability of the procedure was high, with an intrasession 95% confidence interval (CI) of 2.2 dB and an intersession 95% CI of 4.2 dB. CONCLUSIONS: The effect of the NR and directional microphone algorithms was measured to be 2-3 and 3.6-4.4 dB, respectively, using the TNT procedure. Because of its tracking property and reliability, this procedure may hold promise in differentiating among some hearing aid features that also differ in their time course of action.

Evaluation of a Wind Noise Attenuation Algorithm on Subjective Annoyance and Speech-in-Wind Performance.

BACKGROUND: Wind noise is a common problem reported by hearing aid wearers. The MarkeTrak VIII reported that 42% of hearing aid wearers are not satisfied with the performance of their hearing aids in situations where wind is present. PURPOSE: The current study investigated the effect of a new wind noise attenuation (WNA) algorithm on subjective annoyance and speech recognition in the presence of wind. RESEARCH DESIGN: A single-blinded, repeated measures design was used. STUDY SAMPLE: Fifteen experienced hearing aid wearers with bilaterally symmetrical (≤10 dB) mild-to-moderate sensorineural hearing loss participated in the study. DATA COLLECTION AND ANALYSIS: Subjective rating for wind noise annoyance was measured for wind presented alone from 0° and 290° at wind speeds of 4, 5, 6, 7, and 10 m/sec. Phoneme identification performance was measured using Widex Office of Clinical Amplification Nonsense Syllable Test presented at 60, 65, 70, and 75 dB SPL from 270° in the presence of wind originating from 0° at a speed of 5 m/sec. RESULTS: The subjective annoyance from wind noise was reduced for wind originating from 0° at wind speeds from 4 to 7 m/sec. The largest improvement in phoneme identification with the WNA algorithm was 48.2% when speech was presented from 270° at 65 dB SPL and the wind originated from 0° azimuth at 5 m/sec. CONCLUSION: The WNA algorithm used in this study reduced subjective annoyance for wind speeds ranging from 4 to 7 m/sec. The algorithm was effective in improving speech identification in the presence of wind originating from 0° at 5 m/sec. These results suggest that the WNA algorithm used in the current study could expand the range of real-life situations where a hearing-impaired person can use the hearing aid optimally.

Effects of Training on the Use of a Manual Microphone Shutoff on a BiCROS Device.

BACKGROUND: Bilateral contralateral routing of signals (BiCROS) hearing aids function to restore audibility of sounds originating from the side of the unaidable ear. However, when speech is presented to the side of the aidable ear and noise to the side of the unaidable ear, a BiCROS arrangement may reduce intelligibility of the speech signal. This negative effect may be circumvented if an on/off switch is available on the contralateral routing of signals (CROS) transmitter. PURPOSE: This study evaluated if the proper use of the on/off switch on a CROS transmitter could enhance speech recognition in noise and sound localization abilities. The participants' subjective reactions to the use of the BiCROS, including the use of the on/off switch in real-life were also evaluated. RESEARCH DESIGN: A between-subjects, repeated-measures design was used to assess differences in speech recognition (in quiet and in noise) and localization abilities under four hearing aid conditions (unaided, unilaterally aided, fixed BiCROS setting, and adjusted BiCROS setting) with speech and noise stimuli presented from different azimuths. Participants were trained on the use of the on/off switch on the BiCROS transmitter before testing in the adjusted BiCROS settings. Subjective ratings were obtained with the Speech, Spatial, and Sound Quality (SSQ) questionnaire and a custom questionnaire. STUDY SAMPLE: Nine adult BiCROS candidates participated in this study. DATA COLLECTION AND ANALYSIS: Participants wore the Widex Dream-m-CB hearing aid on the aidable ear for 1 week. They then wore the BiCROS for the remainder of the study. Speech recognition and localization testing were completed in four hearing aid conditions (unaided, unilateral aided, fixed BiCROS, and adjusted BiCROS). Speech recognition was evaluated during the first three visits, whereas localization was evaluated over the course of the study. Participants completed the SSQ questionnaire before each visit. The CROS questionnaire was completed at the final visit. A repeated measures analysis of variance with Bonferroni post hoc analysis was used to evaluate the significance of the results on speech recognition, localization, and the SSQ. RESULTS: The results revealed that the adjusted BiCROS condition improved speech recognition scores by 20 rau (rationalized arcsine unit) when speech was presented to the aidable ear and localization by 37% when sounds are presented from the side of the unaidable ear over the fixed BiCROS condition. Statistically significant benefit on the SSQ was also noted with the adjusted BiCROS condition compared to the unilateral fitting. CONCLUSIONS: These findings supported the value of an on/off switch on a CROS transmitter because it allows convenient selective transmission of sounds. It also highlighted the importance of instructions and practice in using the BiCROS hearing aid successfully.