Assess the real-world performance of popular imputation algorithms on cochlear implant (CI) candidate audiometric data.
7,451 audiograms from patients undergoing CI candidacy evaluation were pooled ...from 32 institutions with complete case analysis yielding 1,304 audiograms. Imputation model performance was assessed with nested cross-validation on randomly generated sparse datasets with various amounts of missing data, distributions of sparsity, and dataset sizes. A threshold for safe imputation was defined as root mean square error (RMSE) <10dB. Models included univariate imputation, interpolation, multiple imputation by chained equations (MICE), k-nearest neighbors, gradient boosted trees, and neural networks.
Greater quantities of missing data were associated with worse performance. Sparsity in audiometric data is not uniformly distributed, as inter-octave frequencies are less commonly tested. With 3-8 missing features per instance, a real-world sparsity distribution was associated with significantly better performance compared to other sparsity distributions (Δ RMSE 0.3 dB- 5.8 dB, non-overlapping 99% confidence intervals). With a real-world sparsity distribution, models were able to safely impute up to 6 missing datapoints in an 11-frequency audiogram. MICE consistently outperformed other models across all metrics and sparsity distributions (p < 0.01, Wilcoxon rank sum test). With sparsity capped at 6 missing features per audiogram but otherwise equivalent to the raw dataset, MICE imputed with RMSE of 7.83 dB 95% CI 7.81-7.86. Imputing up to 6 missing features captures 99.3% of the audiograms in our dataset, allowing for a 5.7-fold increase in dataset size (1,304 to 7,399 audiograms) as compared with complete case analysis.
Precision medicine will inevitably play an integral role in the future of hearing healthcare. These methods are data dependent, and rigorously validated imputation models are a key tool for maximizing datasets. Using the largest CI audiogram dataset to-date, we demonstrate that in a real-world scenario MICE can safely impute missing data for the vast majority (>99%) of audiograms with RMSE well below a clinically significant threshold of 10dB. Evaluation across a range of dataset sizes and sparsity distributions suggests a high degree of generalizability to future applications.
The electrically evoked compound action potential (eCAP) represents the synchronous firing of a population of electrically stimulated auditory nerve fibers. It can be directly recorded on a ...surgically exposed nerve trunk in animals or from an intra-cochlear electrode of a cochlear implant. In the past two decades, the eCAP has been widely recorded in both animals and clinical patient populations using different testing paradigms. This paper provides an overview of recording methodologies and response characteristics of the eCAP, as well as its potential applications in research and clinical situations. Relevant studies are reviewed and implications for clinicians are discussed.
Access to cochlear implantation varies greatly around the world. It is affected by factors that are specific to each country's health care system, by awareness, and by societal attitudes regarding ...deafness.
Cochlear implant clinicians and researchers from six countries explored and discussed these variations and their likely causes: Robert Briggs from Australia; Wolfe-Dieter Baumgartner from Austria; Thomas Lenarz from Germany; Eva Koltharp from Sweden; Christopher Raine from the United Kingdom, and Craig Buchman, Donna Sorkin, and Christine Yoshinago from the United States.
Utilization rates are quite different for the pediatric and adult demographics in all six countries. Pediatric utilization ranges in the six countries (all in the developed world) ranged from a low of 50% in the United States to a high of 97% in Australia. Adult utilization is less than 10% everywhere in the world.
Pediatric access to care was excellent for children with the exception of Germany and the United States where there is an inadequate referral system. Adult utilization was low everywhere because of the lack of screening for adults and the fact that primary care physicians and even audiologists are unfamiliar with CI candidacy criteria and outcomes, and hence typically do not make patient referrals.
To describe outcomes from cochlear implantation with a new, slim modiolar electrode array.
Retrospective cohort study.
Tertiary referral centers.
Adult cochlear implant candidates.
Cochlear ...implantation with CI532 (Cochlear Corp).
Pre- and postoperative speech perception scores, operative details, and postoperative computed tomography (CT) reconstructions of array location.
One hundred seventeen patients are implanted to date. There were eight tip rollovers identified with intraoperative x-ray and resolved with reinsertion. An additional rollover was identified on postoperative CT. CT reconstructions in 17 of 23 patients showed complete scala tympani placement with a wrap factor of 58% (range 53-64%) and a mean insertion angle of 406 degrees (range 360-452 degrees). Three implants demonstrated array translocation with electrodes in the scala vestibuli. Consonant-nucleus-consonant word scores improved from 10% preoperatively to 48% at 3 months postoperatively. Pure-tone thresholds were preserved postoperatively in 37 to 52% of patients across frequencies from 250 to 4000 Hz. Functional pure-tone thresholds (≤80 dB) were recorded in 9 to 25% of patients.
CI532 array insertion results in consistent scala tympani location and provides expected audiologic performance. Initial hearing preservation results are not consistent with current electro-acoustic arrays.
Although significant progress has been made in understanding outcomes following cochlear implantation, predicting performance remains a challenge. Duration of hearing loss, age at implantation, and ...electrode positioning within the cochlea together explain ~ 25% of the variability in speech-perception scores in quiet using the cochlear implant (CI). Electrocochleography (ECochG) responses, prior to implantation, account for 47% of the variance in the same speech-perception measures. No study to date has explored CI performance in noise, a more realistic measure of natural listening. This study aimed to (1) validate ECochG total response (ECochG-TR) as a predictor of performance in quiet and (2) evaluate whether ECochG-TR explained variability in noise performance. Thirty-five adult CI recipients were enrolled with outcomes assessed at 3-months post-implantation. The results confirm previous studies showing a strong correlation of ECochG-TR with speech-perception in quiet (r = 0.77). ECochG-TR independently explained 34% of the variability in noise performance. Multivariate modeling using ECochG-TR and Montreal Cognitive Assessment (MoCA) scores explained 60% of the variability in speech-perception in noise. Thus, ECochG-TR, a measure of the cochlear substrate prior to implantation, is necessary but not sufficient for explaining performance in noise. Rather, a cognitive measure is also needed to improve prediction of noise performance.
Early hearing detection and intervention (EHDI) is a newborn hearing screening system created to detect infants with hearing loss (HL) and intervene to reduce language and communication impairment. ...Early hearing detection (EHD) consists of three sequential stages: identification, screening, and diagnostic testing. This study longitudinally reviews each stage of EHD in each state and proposes a framework to improve utilization of EHD data.
A retrospective public database review was conducted, accessing publicly available data from the Centers for Disease Control and Prevention. Summary descriptive statistics were utilized to generate a descriptive study of EHDI programs in each U.S. state from 2007 to 2016.
Data over 10 years from 50 states as well as Washington, DC were included in this analysis, creating up to 510 data points per analysis. Hundred percent (85 to 105) (median min to max) of newborns were identified by and entered EHDI programs. Ninety-eight percent (51 to 100) of identified infants completed screening. Of the infants who screened positive for HL, the proportion that received diagnostic testing was 55% (1 to 100). The overall proportion of infants who failed to complete EHD was 3% (1 to 51). Of the infants who fail to complete EHD 70% (0 to 100) are from missed screenings, 24% (0 to 95) are from missed diagnostic testing, and 0% (0 to 93) are from missed identification. Although there are more infants missed at screening, it was estimated, with limitations, that there is an order of magnitude more infants with HL among those who did not complete diagnostic testing compared with those who did not complete screening.
Analysis demonstrates high completion rates at both identification and screening stages, whereas the diagnostic testing stage demonstrates low and highly variable completion rates. The low completion rates at diagnostic testing create a bottleneck in the EHD process and the large variability impedes the comparison of HL outcomes across states. Analysis also demonstrates that among all stages of EHD, whereas the largest number of infants are missed at screening, the largest number of children with HL are likely missed at diagnostic testing. Therefore, a focus by individual EHDI programs on addressing causes of low diagnostic testing completion rates would yield the greatest increase in the identification of children with HL. Potential causes of low diagnostic testing completion rates are further discussed. Finally, a new vocabulary framework is proposed to facilitate further study of EHD outcomes.
Hypothesis:
A simulated, multicolor, multi-material temporal bone model can be created using 3-dimensional (3D) printing that will prove both safe and beneficial in training for actual temporal bone ...surgical cases.
Background:
As the process of additive manufacturing, or 3D printing, has become more practical and affordable, a number of applications for the technology in the field of Otolaryngology–Head and Neck Surgery have been considered. One area of promise is temporal bone surgical simulation.
Methods:
Three-dimensional representations of human temporal bones were created from temporal bone computed tomography (CT) scans using biomedical image processing software. Multi-material models were then printed and dissected in a temporal bone laboratory by attending and resident otolaryngologists. A 5-point Likert scale was used to grade the models for their anatomical accuracy and suitability as a simulation of cadaveric and operative temporal bone drilling.
Results:
The models produced for this study demonstrate significant anatomic detail and a likeness to human cadaver specimens for drilling and dissection.
Conclusion:
Simulated temporal bones created by this process have potential benefit in surgical training, preoperative simulation for challenging otologic cases, and the standardized testing of temporal bone surgical skills.
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