COCHLEAR IMPLANTS INTERNATIONAL最新文献

Objectives: Cochlear implants restore functional hearing but may cause side effects like facial nerve stimulation, sound sensitivity or reactive tinnitus. The present study aimed to establish a general framework for optimizing stimulation parameters to manage these side effects while maximizing speech perception performance. A second objective was to understand how side effect origins impact treatment outcomes.

Methods: Eight adult cochlear implant subjects had intolerable side effects that rendered device usage difficult or even impossible. New maps were created by reducing stimulation levels, increasing pulse duration, reducing stimulation rate, altering channel gains and frequency maps, deactivating problematic electrodes, or a combination of the above. Outcomes were measured in terms of side effect reduction and changes in speech performance.

Results: Facial nerve stimulation was reduced or eliminated in five of five subjects. Sound hypersensitivity was eliminated in two of two subjects. Tinnitus was alleviated in three of four subjects, while the remaining one with cerebellar malformation experienced no change. Speech performance was either maintained or improved in all subjects. Except for the subject with cerebellar malformation who chose to explant the device, all subjects were able to use the implant effectively without bothersome side effects.

Discussion: Facial nerve stimulation is usually related to electric current spread on the same side, which can be effectively managed by customized strategies. In contrast, the origins of sound sensitivity and reactive tinnitus are more variable and likely more difficult to manage.

Conclusion: Customized mapping can alleviate cochlear implant side effects without compromising speech performance.

Objectives: The purpose of the study was (1) to retrospectively analyze ECochG data and compare it with the current literature. (2) to explore the relationship between ECochG and post-op audiological assessments.

Methods: This retrospective study included all patients with intraoperative and postoperative ECochG measurements and postoperative audiologic testing. ECochG were performed during CI insertion regardless of the preoperative hearing status. Preoperative and postoperative assessments were extracted from the medical records.

Results: A total of 35 patients (42 ears) met the inclusion criteria. Intra-op ECochG response was measurable in 17 of 42 ears (40.5%). The mean peak amplitude found was 103.3 µvolts. The type of electrode array was not associated with the ECochG amplitude (p = .630). Post-op ECochG thresholds were significantly correlated with behavioral thresholds after a month of CI implantation (p < 0.05).

Conclusions: ECochG responses were measurable in individuals with mean preop pure tone thresholds of 66 dB HL at 250 Hz, 77 dB HL at 500 Hz, 84 dB HL at 1 kHz and 92 dB HL at 2kHz. The type of electrode was not associated with the ECochG peak nor with greater preservation of residual hearing. Post-op ECochG thresholds were significantly correlated with post-op thresholds.

Objective: Neurophysiologic measures like the electrically evoked Stapedius Reflex Threshold (eSRT) offer valuable insights into personalized responses to Cochlear Implant (CI) stimuli. This study evaluates the effects of stimulation current amplitude and the number of stimulating electrodes on eSRT and its correlation with the Most Comfortable Loudness level (MCL or C-level) in all-polar, pseudo-monophasic, pulse-width loudness coded stimulations.

Approach: The study was conducted on seventeen adult patients with Oticon Medical implants. In these implants, current amplitude remains constant while loudness is coded through pulse-width. Stimulation amplitudes were set to low (default clinical) and high values, using single or multi electrode groups of 1, 3, and 5 (G1, G3, and G5) across five cochlear regions, spanning from apical to basal. For each amplitude and group, the eSRT detection rate and correlation with MCL were analyzed regionally and overall.

Results: Higher eSRT detection rates were observed in the contra-lateral ear, with G3 and G5 significantly enhancing detection over G1 for both low and high amplitudes. The current amplitude facilitated eSRT invocation, particularly for G1 and patients with higher MCLs. The correlation between eSRT and MCL was relatively high (r = 0.64-0.87) across all conditions, indicating accurate MCL estimation from eSRT at both low and high amplitudes.

Discussions: Among all condition interactions (amplitude, side, electrodes), low-amplitude contra-lateral G5 and high-amplitude contra-lateral G3 showed optimal modes for estimating MCL from eSRT, with linear slopes near 1.0, and detection rates of 54% and 63%, respectively. High-amplitude contra-lateral G5 further increased detection to 68%, though with a slope of 0.8, requiring a correction factor. These findings provide insights into eSRT mechanisms and its application in pseudo-monophasic all-polar CI programming.

Conclusion: The eSRT detection rate can be improved in pulse-width modulation cochlear implants by using multi-electrode stimulation and/or increasing the stimulation amplitude beyond the default clinical value, without significantly affecting the correlation coefficient between eSRT and MCL.

Objective: The objective of this study was to determine how the presentation of unprocessed speech, either ipsilaterally (to simulate electro-acoustic stimulation, EAS) or contralaterally (to simulate bimodal stimulation), alongside vocoder-processed speech affects the efficiency of spoken word processing.

Method: Gated word recognition was performed under four listening conditions: full-spectrum speech, vocoder-processed speech, electro-acoustic stimulation (EAS), and bimodal stimulation. In the EAS condition, low-frequency unprocessed speech and high-frequency vocoder-processed speech were presented to the same ear, while in the bimodal condition, full-spectrum speech was presented to one ear and vocoder-processed speech to the other.

Results: Listeners identified target words accurately with just over half of the word duration in the full-spectrum condition, whereas nearly the entire word was required for correct identification with vocoder-processed speech. Combining full-spectrum speech and vocoder-processed speech, whether ipsilaterally or contralaterally, led to significant improvements in gated word recognition. Full-spectrum speech yielded the best-gated word recognition performance, followed by bimodal stimulation, with intermediate results from EAS and the lowest performance from the vocoder condition.

Conclusion: Inherent limitations in CI spectral resolution can impair spoken word processing. Adding acoustic stimulation can improve gated word recognition performance. Bimodal stimulation significantly enhances lexical processing timing compared to EAS in one ear.

Objectives: The current study aims to describe subjects and audiological profiles of children with congenital inner ear anomalies (IEAs).

Materials and methods: A total of 193 children with sensorineural hearing loss (SNHL) and radiological evidence of one or more congenital IEAs were included.

Results and discussion: The most common IEAs in the current study was enlarged vestibular aqueduct (EVA) either isolated or associated with other IEAs. Incomplete partition (IP) with its three types (IP I, IP II, and IP III) was the second common anomaly, followed by cochlear hypoplasia (CH). At the time of radiological diagnosis, hearing loss degrees ranged from mild to profound in children with EVA, CH III, and CH IV with the majority having severe or profound degrees. The prevalence of severe and profound degree of hearing loss was higher in children with IP than children with isolated EVA or CH III and CH IV. In children with isolated EVA, hearing loss was asymmetric in 52.2% and progressive in 58%. In children with CH III and CH IV, hearing loss was asymmetric but stationary. Only children with EVA and IP III had air-bone gab (ABG) at low frequencies, while children with other IEAs did not have ABG except if there was an association with EVA. Children with severe anomalies such as CH I, CH II, common cavity, and cochlear nerve hypoplasia had profound degrees of hearing loss or just sound detection.

Conclusions: Knowing the audiological profile of children with IEAs has important clinical implications in the management of those children.

Objectives: The aim of this study wasto systemically examine the relationship between AutoNRT thresholds and subjective programming levels by controlling for individual subject variation, and further, to propose an alternative way to calculate the AutoNRT threshold profile for programming purposes.

Methods: The study was a prospective observational study. AutoNRT thresholds, T- and C-levels were recorded at six and twelve months after activation. All subjects had received a CI24RE implant.

Results: Forty-one adults participated in the study. A linear mixed-effects model analysis of the relationship between the AutoNRT thresholds and the T-and C-levels resulted in a large unexplainable variation between subjects, the standard deviation was between 15.42 and 18.89 CL. However, the study showed that the profiles for the T- and C-levels could be predicted with an acceptable accuracy from AutoNRT. A model for calculating profiles from AutoNRT thresholds based on linear regression resulted in the lowest deviation from the subjective programming thresholds, with somewhat better results for C-levels than T-levels.

Conclusion: The results from this study showed that the predictability was reasonable when calculating the profiles for the T- and C-levels based on AutoNRT. And, further, that AutoNRT thresholds can be used when programming cochlear implants, to make global adjustments without predicting actual T- or C-levels.

Objective: There's a need to highlight prognostic factors (PFs) determining hearing preservation in cochlear implantation (HPCI), as currently there is large variability in outcomes. Given the potential benefits of HPCI, it is important to understand the factors influencing this variation. We apply a novel methodology to outline and assess the accuracy of prognostic factors reporting for HPCI.

Data sources: A preferred reporting item for systematic reviews and meta-analyses compliant systematic review, searches applied to Medline, EMBASE, and Cochrane.

Study selection: The CHARMS-PF tool assessed the strength of PF study designs.

Data extraction: The QUIPS tool assessed for risk of bias.

Data synthesis and results: Ninety-two papers were suitable for data extraction. The domain's preoperative hearing loss, size of the round window opening, round window accessibility, surgical insertion speed and route (Round window or cochleostomy), electrode length and type were identifiable exploratory PFs for HPCI. Overall, the study's heterogeneity and risk of bias precluded reporting by forest plots and meta-analysis.

Conclusions: Most exploratory PF studies for HPCI are hindered by the risk of bias. This systematic review identifies potential independent PFs which should be measured, and adjusted for, in future confirmatory studies using a multivariate analysis. This would determine the independent prognostic effects associated with HPCI while facilitating prognostic model development and the predict individual HPCI.

Objectives: Considering the high prevalence of temporal bone imaging and the growing tendency to replace the CT scan with CBCT in this field, it seems necessary to determine the optimal radiation conditions in each commercial CBCT brand to obtain the best diagnostic images with minimal patient radiation.

Methods: A dry human skull was imaged by 6 radiation protocols in 4 different CBCT devices. The images of anatomical landmarks including cochlea, lamina spiralis, facial canal, semicircular canals, and modiolus, were reconstructed. Then, the quality of these images was determined by 3 observers based on a 4-point scoring system. The Kappa coefficient was adopted to evaluate the observer's agreement, and the Kruskal-Wallis and Mann-Whitney tests were used to compare the mean scores of the protocols and the superiority of the protocols in each device, respectively.

Results: There was no statistically significant difference between the mean scores of the protocols in the Acteon and NewTom devices. In the Kodak and Planmeca devices, the recommended protocol for imaging the temporal bone is protocol 1 and protocol 3, respectively.

Conclusion: Considering the replacement of the CBCT device for temporal bone imaging and the variety of related protocols in these devices, to reduce the overall society dose, it seems necessary to conduct further studies to determine the optimal radiation conditions in each device. In addition, the ability to unilaterally image the temporal bone is an underappreciated advantage of the CBCT over the CT, which prescribers are not familiar with.

Objective: This study aims to identify the acquisition features of functional near-infrared spectroscopy (fNIRS) in cochlear implant users.

Methods: A systematic literature review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, EMBASE, LILACS, Web of Science, Scopus, PsycINFO, IEEE Xplore, Google Scholar, and ProQuest Dissertations & Theses Global were searched using the PECOS acronym. Inclusion criteria encompassed studies involving fNIRS with speech stimuli in cochlear implant users of any age, with information on acquisition parameters and features. Risk of bias assessment was performed using the Joanna Briggs Institute tool.

Results: Nineteen studies were included, with thirteen exhibiting a low risk of bias. Noteworthy uniformity was observed in certain fNIRS acquisition features among cochlear implant users, including the waking state (awake), auditory stimuli of words or phrases presented in a free field, visual stimuli displayed during data collection as a secondary task, recording of responses in the bilateral temporal lobe, and a three-centimeter distance between optodes. Variations in acquisition were attributed to differing study purposes.

Conclusion: This review identifies common acquisition characteristics for fNIRS in cochlear implant users. Multicenter research efforts are advocated to further advance the utility of fNIRS in this population.

Advances in worn and implantable hearing device technology is such that hearing can now be successfully (re)habilitated from mild to profound hearing loss. Whilst hearing services have access to the latest digital hearing devices, bone conduction and cochlear implants, two main research and clinical challenges remain within the pediatric population, namely matching the device to the hearing loss and needs of the individual (e.g. borderline cochlear implant candidacy), and early identification to facilitate timely intervention across the pediatric life span. Deteriorating and later-onset hearing loss are exemplars of the challenges faced.