Audiology and Neuro-Otology最新文献

Introduction: Cochlear implant outcomes vary widely and are difficult to predict, with traditional methods explaining <20% of variance. This study tested whether machine learning approaches offer superior performance predicting outcomes and better identify key factors driving variability compared to traditional linear methods.

Methods: This retrospective observational study analyzed clinical data from 2251 adult cochlear implant recipients (>18 years) with post-lingual hearing loss (onset >15 years) across fifteen centers in Australia, Europe, and North America. Data were collected between 2003 and 2011, with follow-up at 6 months and 2 years post-implantation. Linear Regression was compared against seven other machine learning models: Extreme Gradient Boosting (XGBoost), Random Forest, Categorical Boosting (CatBoost), Light Gradient Boosting Machine (LightGBM), Support Vector Regression, Ridge Regression, and Lasso Regression. Models were optimized using grid search with 5-fold cross-validation on an 80/20 training-test split. The primary outcome was prediction of percentile-ranked postoperative speech recognition scores in quiet, assessed using mean squared error (MSE) and coefficient of determination (R²). SHapley Additive exPlanations (SHAP) values identified feature importance.

Results: XGBoost achieved the best performance with a modest but significant 4.11% reduction in prediction error compared to linear regression (mean squared error: 739.67±19.27 vs 771.41±21.51, P = 0.003; R²: 0.114±0.011 vs 0.076±0.012, P < 0.001). All ensemble methods significantly outperformed linear regression. Duration of cochlear implant use, age at implantation, duration of severe/profound hearing loss, and preoperative hearing scores emerged as the most influential predictors across all models.

Conclusions: Machine learning models modestly improve cochlear implant outcome prediction, though substantial variance remains unexplained (>80%). Critical determinants of cochlear implant performance likely extend beyond variables routinely measured in clinical practice, highlighting the need for novel predictive factors.

Background: The aging process is accompanied by sensory, motor, and cognitive declines that increase the risk of balance disorders. Fatigue is a prevalent yet often overlooked symptom among older adults.

Objective: This study examines the relationship between fatigue and balance in individuals 60 years and older to provide evidence for preventive and rehabilitative strategies.

Methods: Fatigue was assessed using the Fatigue Assessment Scale (FAS) and the Fatigue Impact Scale (FIS), while balance was evaluated with the Timed Up and Go (TUG) test, the Tinetti Balance and Gait Test (TBT-TGT), and the Single-Leg Stance Test (SLST).

Results: While fatigue had a negative impact on both static and dynamic balance, no statistically significant differences were detected between the fatigued and severely fatigued groups. Analyses revealed weak to moderate negative correlations between fatigue scales and measures of both static and dynamic balance, with mental fatigue demonstrating a comparatively stronger relationship with static balance. In the regression analysis, the model including age and mental fatigue overall explained 27.9% of the variance in single-leg stance duration.

Conclusions: The results of our study indicate that fatigue markedly impairs both static and dynamic balance performance among older adults.

Introduction: Locally applied dexamethasone therapy of the inner ear is commonly used to treat disorders such as Meniere's disease and idiopathic sudden sensorineural hearing loss. Dexamethasone is also being used in conjunction with cochlear implantation to reduce electrode impedances and fibrous tissue formation around the implant. The variety of formulations currently in use makes it difficult to compare the dosing levels resulting from different therapies.

Methods: We have used the FluidSIM cochlear fluid simulation program to calculate perilymph and plasma dexamethasone levels achieved by a variety of dosing approaches used clinically in humans. Identical pharmacokinetic parameters for perilymph and plasma were used for each delivery condition.

Results: Each of the delivery protocols was calculated to generate therapeutic concentrations in perilymph, but the time course of influence differed markedly between them. Some protocols generate concentrations in the blood that are above therapeutic concentration, increasing the potential for systemic side effects.

Discussion: Detailed simulations of delivery procedures allow different approaches to be compared quantitatively, giving a measure of dosing efficiency and allowing the merits of each protocol to be compared. Cochlear implants provide the most efficient dosing, generating therapeutic concentrations in the cochlea with minimal systemic influence. For intratympanic delivery, Spiral Therapeutics SPT-2101 provides therapeutic concentrations in perilymph with minimal systemic dosing. Conventional IT therapy with dexamethasone phosphate provides brief therapeutic concentrations in perilymph but substantial systemic exposure, with plasma concentration calculated to exceed therapeutic levels.

Objective: This study aims to assess the effectiveness of the ForwardFocus (FF) feature in cochlear implant (CI) users by evaluating its impact on speech comprehension in noisy environments, potentially improving communication outcomes for individuals with hearing loss.

Methods: A prospective study was conducted on 48 CI users from an audiology clinic over a 7-month period, between July 2023 and February 2024. Native Arabic speakers, using either N7 or Kanso2 external processors with the FF feature, were recruited. The study measured aided audiometry, word recognition score, and speech comprehension in noise using the Arabic Matrix Test with and without the FF feature, along with a survey assessing ease of use and satisfaction among other factors.

Results: The impact of FF on speech perception and user experience in CI users were evaluated. FF significantly improved speech perception in noise (p < 0.001), with users reporting high satisfaction (54.3% very satisfied, 26.1% satisfied) and intention to continue using FF (97.8%). Most participants used FF 1-2 times a week (56.5%), with 17% using it daily. Most found its noise reduction to be adequate (82.6%).

Conclusion: FF effectively enhanced speech understanding, with users expressing high satisfaction and intention to continue using the feature. This suggests FF's ability to improve communication and quality of life for CI users.

Introduction: Optimizing inner ear access is necessary for the genetic and regenerative treatment of sensorineural hearing loss. This is a descriptive histological study, with three-dimensional modeling of the microanatomy of minimally invasive transcanal access routes to the scala tympani through the round window, and suggested form and dimensions of injection needles for inner ear drug delivery.

Methods: Three-dimensional models of eight human temporal bone histological sections were created to measure key anatomical relationships and optimal needle trajectories.

Results: To spare the inner ear structures and reach the greatest depth in the scala tympani, the optimal trajectory via the round window is achieved with a needle leaned on and bent at the superiormost point of the round window niche operculum. The length of the needle's medial part is between 1.375 mm (1.2-1.6 mm) and 3.49 mm (2.8-4.3 mm), with a bend angle of 147° (123-167°). The penetration point of the round window membrane is its vertical axis center, reducing the risk of damage to the inner ear structure and avoiding the crista fenestra. The crista may shift the penetration point inferiorly when visible and not found behind the round window membrane. In all eight temporal bones, the crista never reached the center of the round window membrane, with the horizontal distance between the crista edge and the center being 0.55 mm (0.4-0.75 mm).

Conclusion: The data reveal the form and size factors for optimal transcanal access to the inner ear for structure- and function-preserving drug delivery.

Aim: There are a range of approaches to intraoperative electrocochleography (ECochG) monitoring across different implant systems, and these show inconsistent results. Here, we synthesize by meta-analysis the evidence for real-time intracochlear ECochG recorded during cochlear implantation predicting residual hearing.

Methods: Inclusion criteria included original studies in which real-time ECochG was undertaken on a commercial cochlear implant (CI) and residual hearing outcomes at least 4 weeks after implantation were reported. Thirteen studies comprising 313 individual patient data sets met inclusion criteria. Full data sets were sought from the authors. Studies were rated for quality and bias. Details about study design (observational or interventional) and electrode characteristics (lateral wall or perimodiolar) were extracted. Relative hearing loss across the low frequencies (250-1,000 Hz) was the main outcome, with decibel loss and functional hearing as secondary outcomes. Effects were explored by forest plot, and then linear mixed modelling on the full data sets. Sensitivity analyses included recalculation of hearing preservation using thresholds across different frequencies.

Results: Thirteen studies, including 313 full patient data sets, were included, and meta-analysis was performed on lateral wall electrodes. A drop of ECochG amplitude of >30%, even if transient, predicted residual hearing across all metrics (decibel, relative, and functional), and data-synthesis methods (forest plots and linear modelling) for all systems where real-time measurements were available. A drop of amplitude of at least 60% across insertion predicted relative but not decibel hearing loss in linear mixed modelling. The "pattern" of ECochG drop, as described by Harris in 2017, did not predict residual hearing by any method.

Discussion: The only truly "real-time" measurement that predicted residual hearing was an instantaneous drop in ECochG amplitude, with or without recovery. Large drops over the insertion did too, but these can only be calculated after insertion, and after the cochlear trauma has been done. All CI systems now offer real-time monitoring - these results provide guidance on how best to use it to optimize clinical outcomes.

Introduction: The speech reception threshold (SRT) test is a fundamental component of audiological assessment. It helps in assessment of speech recognition, fitting of hearing aids and cochlear implant. This test facility is not available for Urdu speakers. Thus, the objective of the study is to digitally record and psychometrically evaluate Urdu spondee word list for SRT testing.

Methods: A total of n = 107 spondee words were selected from a prior study. These words were recorded digitally by a native female Urdu speaker in a studio. The words were presented to normal hearing Urdu speakers between -10 and 20 decibels of hearing levels (dB HL). The performance intensity of these words was assessed psychometrically as intercept, slope, threshold, slope at 50%, slope between 20 and 80%. The minor intensity adjustment of each word was made equivalent to threshold. The words with slope steeper than ≥7%/dB were included in the final list.

Results: A list of 46 Urdu spondee words was finalized. The average psychometric slope of these final words between 20% and 80% was 7.06-10.70%/dB ± 0.83. The slope at 50% ranged from 8.33%/dB HL to 13.33%/dB HL ± 1.56 dB. The threshold for the 46 spondee words varied from 7.43 dB to 10.80 dB HL ± 0.77 dB.

Conclusion: Digitally recorded Urdu spondee word list is valid for assessment of SRT testing in Urdu speakers.

Introduction: Tinnitus is the perception of sound when no sound is present. Due to its heterogenous nature, tinnitus can impact people differently. Tinnitus disorder occurs when the perception of tinnitus affects quality of life. Personalized digital mHealth therapy approaches to tinnitus treatment have been proposed to address the heterogeneity of tinnitus. To build self-efficacy in tinnitus management, there should be alignment between therapeutic objectives and the needs of end users. This survey was undertaken to learn the desirable features a digital therapy should have from the perspective of people with tinnitus.

Methods: A cross-sectional online survey of 986 people on a tinnitus research list was undertaken asking questions about their experience of tinnitus and desirable features in a digital tinnitus therapy.

Results: The highest rated problems with tinnitus were "loss of peace and quiet" and "sound intrusiveness" (median [Mdn] 4/5). The most common problems that participants wanted help with were learning about treatments and management, hearing, tinnitus elimination, sleep, and reduction in tinnitus. Participants rated sound-based brain-training games (training to focus away from tinnitus) as the top feature they wanted in digital therapy (Mdn 5/5, extremely important). Mann-Whitney U tests identified differences in problems and solutions when variables were grouped according to gender (female/male), self-reported hearing loss (yes/no), country of residence (New Zealand [NZ], non-NZ), and app use (yes/no). Females and males rated tinnitus problems differently, and females tended to rate solutions as more valuable than males.

Conclusions: A survey of many people with tinnitus identified common problems and preferred solutions. Although a high percentage of responders wanted tinnitus eliminated, a large number recognized the desirability of management through sound-based and psychological approaches. This information can assist clinicians and researchers developing therapies.

Introduction: Slim perimodiolar electrodes (PSEs) are designed for close modiolar proximity, but deviations from ideal placement may affect speech perception. This study investigates the prevalence, radiologic characteristics, and audiologic outcomes of abnormally positioned PSE arrays and proposes intraoperative management strategies.

Methods: We retrospectively reviewed 239 adults implanted with Cochlear® PSE arrays (2015-2023). Postoperative CT scan identified arrays positioned laterally to mid-scala without tip fold-over. Objective metrics such as angular insertion depth (AID), intracochlear position index (ICPI), wrapping factor (WF), and maximum insertion angle were compared to a control group with normal positioning (n = 52). Speech perception outcomes at 3 and 12 months were assessed using monosyllabic word tests and compared to a reference cohort (n = 1,414).

Results: Abnormal positioning occurred in 3% (n = 7). All arrays remained within scala tympani but had shallower insertions (AID 296° vs. 392°), greater lateralization (ICPI 0.52 vs. 0.33), and higher WF (0.62 vs. 0.36). Compared to controls, speech scores were lower at 3 months (33% vs. 65%) and 12 months (45% vs. 74%). Intraoperative X-rays did not detect these deviations.

Conclusion: Abnormal PSE placement is uncommon but associated with poorer speech outcomes. Surgeons should assess electrode shape intraoperatively and consider reinsertion if the classic curl is absent. Postoperative CT remains critical for quality assurance. Tailored intraoperative strategies are needed to prevent lateralization and optimize outcomes.

Objective: This study aimed to compare cervical vestibular evoked myogenic potentials (cVEMP) elicited by tone burst (TB) and narrow band level-specific chirp (NB LS-CE Chirp) stimuli at 500, 1,000, 2,000, and 4,000 Hz in healthy individuals.

Methods: Thirty-two healthy participants (15 females, 17 males; mean age: 24.59 ± 1.93 years) underwent otoscopic examination, pure-tone audiometry, and cVEMP testing at 95 dB nHL using TB and NB LS-CE Chirp stimuli. P1 latency, N1 latency, and P1N1 amplitude were recorded.

Results: At 500 Hz, both stimuli elicited responses in all subjects. Significant differences in P1 latency, N1 latency, and P1N1 amplitude were found between the stimuli at 500 and 1,000 Hz (p < 0.05). No significant differences were observed at 2,000 and 4,000 Hz (p > 0.05).

Conclusion: NB LS-CE Chirp stimuli generate larger and earlier cVEMP responses than TB stimuli, particularly at lower frequencies, suggesting higher effectiveness for saccular assessment.