Does Intraoperative Extracochlear Electrocochleography Correlate With Postoperative Audiometric Hearing Thresholds in Cochlear Implant Surgery? A Retrospective Analysis of Cochlear Monitoring.

In recent years, tools for early detection of irreversible trauma to the basilar membrane during hearing preservation cochlear implant (CI) surgery were established in several clinics. A link with the degree of postoperative hearing preservation in patients was investigated, but patient populations were usually small. Therefore, this study's aim was to analyze data from intraoperative extracochlear electrocochleography (ECochG) recordings for a larger group.During hearing preservation CI surgery, extracochlear recordings were made before, during, and after CI electrode insertion using a cotton wick electrode placed at the promontory. Before and after insertion, amplitudes and stimulus response thresholds were recorded at 250, 500, and 1000 Hz. During insertion, response amplitudes were recorded at one frequency and one stimulus level. Data from 121 patient ears were analyzed.The key benefit of extracochlear recordings is that they can be performed before, during, and after CI electrode insertion. However, extracochlear ECochG threshold changes before and after CI insertion were relatively small and did not independently correlate well with hearing preservation, although at 250 Hz they added some significant information. Some tendencies-although no significant relationships-were detected between amplitude behavior and hearing preservation. Rising amplitudes seem favorable and falling amplitudes disadvantageous, but constant amplitudes do not appear to allow stringent predictions.Extracochlear ECochG measurements seem to only partially realize expected benefits. The questions now are: do gains justify the effort, and do other procedures or possible combinations lead to greater benefits for patients?

Intracochlear Recording of Electrocochleography During and After Cochlear Implant Insertion Dependent on the Location in the Cochlea.

To preserve residual hearing during cochlear implant (CI) surgery it is desirable to use intraoperative monitoring of inner ear function (cochlear monitoring). A promising method is electrocochleography (ECochG). Within this project the relations between intracochlear ECochG recordings, position of the recording contact in the cochlea with respect to anatomy and frequency and preservation of residual hearing were investigated. The aim was to better understand the changes in ECochG signals and whether these are due to the electrode position in the cochlea or to trauma generated during insertion. During and after insertion of hearing preservation electrodes, intraoperative ECochG recordings were performed using the CI electrode (MED-EL). During insertion, the recordings were performed at discrete insertion steps on electrode contact 1. After insertion as well as postoperatively the recordings were performed at different electrode contacts. The electrode location in the cochlea during insertion was estimated by mathematical models using preoperative clinical imaging, the postoperative location was measured using postoperative clinical imaging. The recordings were analyzed from six adult CI recipients. In the four patients with good residual hearing in the low frequencies the signal amplitude rose with largest amplitudes being recorded closest to the generators of the stimulation frequency, while in both cases with severe pantonal hearing losses the amplitude initially rose and then dropped. This might be due to various reasons as discussed in the following. Our results indicate that this approach can provide valuable information for the interpretation of intracochlearly recorded ECochG signals.

Stapedotomy Versus Cochlear Implantation for Far Advanced Otosclerosis: Insights From a Patient With Matched Preoperative and Postoperative Function.

OBJECTIVE: To examine patient preference after stapedotomy versus cochlear implantation in a unique case of a patient with symmetrical profound mixed hearing loss and similar postoperative speech perception improvement. PATIENTS: An adult patient with bilateral symmetrical far advanced otosclerosis, with profound mixed hearing loss. INTERVENTION: Stapedotomy in the left ear, cochlear implantation in the right ear. MAIN OUTCOME MEASURE: Performance on behavioral audiometry, and subjective report of hearing and intervention preference. RESULTS: A patient successfully underwent left stapedotomy and subsequent cochlear implantation on the right side, per patient preference. Preoperative audiometric characteristics were similar between ears (pure-tone average [PTA] [R: 114; L: 113 dB]; word recognition score [WRS]: 22%). Postprocedural audiometry demonstrated significant improvement after stapedotomy (PTA: 59 dB, WRS: 75%) and from cochlear implant (PTA: 20 dB, WRS: 60%). The patient subjectively reported a preference for the cochlear implant ear despite having substantial gains from stapedotomy. A nuanced discussion highlighting potentially overlooked benefits of cochlear implants in far advanced otosclerosis is conducted. CONCLUSION: In comparison with stapedotomy and hearing aids, cochlear implantation generally permits greater access to sound among patients with far advanced otosclerosis. Though the cochlear implant literature mainly focuses on speech perception outcomes, an underappreciated benefit of cochlear implantation is the high likelihood of achieving "normal" sound levels across the audiogram.

Clinical Application of the 4K-3D Exoscope System in Cochlear Implantation.

PURPOSE: To evaluate a system for otomicrosurgery based on 4K three-dimensional (3D) exoscope technology and apply it to cochlear implantation. METHODS: An open stereoscopic vision-based surgical system, which differs from traditional surgical microscopes, was created by utilizing 4K stereo imaging technology and combining it with low-latency 4K ultra-high-definition 3D display. The system underwent evaluation based on 57 cochlear implantation operations, three designed microscopic manipulations, and a questionnaire survey. RESULTS: The surgical images displayed by the 4K-3D exoscope system (4K-3D-ES) are stereoscopic, clear, and smooth. The use of 4K-3D-ES in cochlear implantation is not inferior to traditional microscopes in terms of intraoperative bleeding and surgical complications, and the surgical duration is not slower or may even be faster than when using traditional microscopes. The results of micromanipulation experiments conducted on 16 students also confirmed this and demonstrated that 4K-3D-ES can be easily adapted. Furthermore, additional advantages of 4K-3D-ES were gathered. Significantly enlarged and high-definition stereoscopic images contribute to the visualization of finer anatomical microstructures such as chordae tympani, ensuring safer surgery. Users feel more comfortable in their necks, shoulders, waists, and backs. Real-time shared stereoscopic view for multiple people, convenient for collaboration and teaching. The ear endoscope and 4K-3D-ES enable seamless switching on the same screen. High-definition 3D images and videos can be saved with just one click, making future publication and communication convenient. CONCLUSION: The feasibility and safety of 4K-3D-ES for cochlear implantation surgery have been demonstrated. The 4K-3D-ES also offers numerous unique advantages and holds clinical application and promotional value.

Cochlear Implantation in Patients With Osteolytic Labyrinthitis: A Case Series.

OBJECTIVE: To describe the rare process of osteolytic labyrinthitis, previously referred to as labyrinthine sequestrum, which involves progressive obliteration of the bony and membranous labyrinth with eventual supplantation with soft tissue and, in some cases, bony sequestrum. PATIENTS: Three patients with diverse presentations of osteolytic labyrinthitis from two tertiary care academic medical centers. INTERVENTIONS: Case series report analyzing the relevant clinical, radiologic, pathologic, and surgical data on our patients with osteolytic labyrinthitis and comparing these index cases to the existing literature. MAIN OUTCOME MEASURES: We describe the varying image findings seen in osteolytic labyrinthitis on computed tomography and magnetic resonance imaging. Also, we report successful surgical intervention and hearing rehabilitation with cochlear implantation in patients with osteolytic labyrinthitis. RESULTS: Our three patients presented with profound sudden sensorineural hearing loss and vertigo consistent with labyrinthitis. None of the three patients had a history of chronic otitis media. Imaging workup revealed varying degrees of erosion to the otic capsule bone demonstrating the spectrum of disease seen in osteolytic labyrinthitis. Although two cases showed osteolytic changes to the semicircular canals and vestibule, the first case revealed frank bony sequestrum within the obliterated labyrinth. The three cases were taken for surgical debridement and cochlear implantation. CONCLUSIONS: We propose the new term, osteolytic labyrinthitis-previously referred to as labyrinthine sequestrum-to describe the rare spectrum of disease characterized by destruction of the osseous and membranous labyrinth and potential supplantation with bony sequestrum. Cochlear implantation is a viable option in selected patients with osteolytic labyrinthitis.

Endoscopic-Assisted Cochlear Implantation in Far Advanced Otosclerosis.

OBJECTIVES: To evaluate the effectiveness of cochlear implantation (CI) in case of far advanced otosclerosis and to evaluate the value of using intraoperative otoendoscopy to facilitate the identification of the round window membrane and the scala tympani without the need to remove the posterior canal wall or to perform a subtotal petrosectomy. STUDY DESIGN: Retrospective case-series study. SETTING: Tertiary academic CI center. PATIENTS AND METHODS: This study was conducted on patients with far advanced otosclerosis who underwent endoscopic-assisted CI between January 2010 and June 2020 at the same CI center. The minimum follow-up period was 2 years after surgery. RESULTS: Fourteen patients were included in the study. Ten patients had undergone a previous stapedotomy. Electrode insertion in the scala tympani was successfully accomplished in all cases included in the study. There was a statistically significant improvement in pure-tone average and speech discrimination scores in all cases of the study group (p < 0.0001). There were no statistically significant differences in postoperative pure-tone average or speech discrimination scores between cases with and without cochlear ossification or between cases with and without a previous stapedotomy (p > 0.05). CONCLUSION: Endoscopic-assisted CI is an effective option for hearing restoration in patients with far advanced otosclerosis. Otoendoscopy can facilitate visualization and access to the scala tympani without the need to remove the posterior canal wall or to perform a subtotal petrosectomy.

Seven-Year Revision Rates for Cochlear Implants in Pediatric and Adult Populations of an Integrated Healthcare System.

OBJECTIVE: We assessed three cochlear implant (CI) suppliers: Advanced Bionics, Cochlear Limited, and MED-EL, for implant revision requiring reoperation after CI placement. STUDY DESIGN: Retrospective cohort study of integrated-health-system database between 2010 and 2021. Separate models were created for pediatric (age <18) and adult (age ≥18) cohorts. PATIENTS: Pediatric (age <18) and adult (age ≥18) patients undergoing cochlear implantation within our integrated healthcare system. MAIN OUTCOME MEASURE: Revision after CI placement. Cox proportional hazard regression was used to evaluate revision risk and adjust for confounding factors. Hazard ratios (HRs) and 95% confidence intervals (CIs) are presented. RESULTS: A total of 2,347 patients underwent a primary CI placement, and Cochlear Limited was most implanted (51.5%), followed by Advanced Bionics (35.2%) and MED-EL (13.3%). In the pediatric cohort, the 7-year crude revision rate was 10.9% for Advanced Bionics and 4.8% for Cochlear Limited, whereas MED-EL had insufficient cases. In adults, the rates were 9.1%, 4.5%, and 3.3% for Advanced Bionics, MED-EL, and Cochlear Limited, respectively. After 2 years of postoperative follow-up, Advanced Bionics had a significantly higher revision risk (HR = 8.25, 95% CI = 2.91-23.46); MED-EL had no difference (HR = 2.07, 95% CI = 0.46-9.25). CONCLUSION: We found an increased revision risk after 2 years of follow-up for adults with Advanced Bionics CI devices. Although we found no statistical difference between manufacturers in the pediatric cohort, after 2 years of follow-up, there were increasing trends in the revision probability for Advanced Bionics. Further research may determine whether patients are better suited for some CI devices.

Guiding Ethical Decisions in Cochlear Implantation for the Hearing Impaired with Comorbid Psychosis.

AbstractCochlear implants can restore hearing in people with severe hearing loss and have a significant impact on communication, social integration, self-esteem, and quality of life. However, whether and how much clinical benefit is derived from cochlear implants varies significantly by patient and is influenced by the etiology and extent of hearing loss, medical comorbidities, and preexisting behavioral and psychosocial issues. In patients with underlying psychosis, concerns have been raised that the introduction of auditory stimuli could trigger hallucinations, worsen existing delusions, or exacerbate erratic behavior. This concern has made psychosis a relative contraindication to cochlear implant surgery. This is problematic because there is a lack of data describing this phenomenon and because the psychosocial benefits derived from improvement in auditory function may be a critical intervention for treating psychosis in some patients. The objective of this report is to provide an ethical framework for guiding clinical decision-making on cochlear implant surgery in the hearing impaired with psychosis.

Cochlear-implant listeners benefit from training with time-compressed speech, even at advanced ages.

This study evaluated whether adaptive training with time-compressed speech produces an age-dependent improvement in speech recognition in 14 adult cochlear-implant users. The protocol consisted of a pretest, 5 h of training, and a posttest using time-compressed speech and an adaptive procedure. There were significant improvements in time-compressed speech recognition at the posttest session following training (>5% in the average time-compressed speech recognition threshold) but no effects of age. These results are promising for the use of adaptive training in aural rehabilitation strategies for cochlear-implant users across the adult lifespan and possibly using speech signals, such as time-compressed speech, to train temporal processing.

Some, but not all, cochlear implant users prefer music stimuli with congruent haptic stimulation.

Cochlear implant (CI) users often report being unsatisfied by music listening through their hearing device. Vibrotactile stimulation could help alleviate those challenges. Previous research has shown that musical stimuli was given higher preference ratings by normal-hearing listeners when concurrent vibrotactile stimulation was congruent in intensity and timing with the corresponding auditory signal compared to incongruent. However, it is not known whether this is also the case for CI users. Therefore, in this experiment, we presented 18 CI users and 24 normal-hearing listeners with five melodies and five different audio-to-tactile maps. Each map varied the congruence between the audio and tactile signals related to intensity, fundamental frequency, and timing. Participants were asked to rate the maps from zero to 100, based on preference. It was shown that almost all normal-hearing listeners, as well as a subset of the CI users, preferred tactile stimulation, which was congruent with the audio in intensity and timing. However, many CI users had no difference in preference between timing aligned and timing unaligned stimuli. The results provide evidence that vibrotactile music enjoyment enhancement could be a solution for some CI users; however, more research is needed to understand which CI users can benefit from it most.

Exploring the relationship between auditory late latency response and language age in children using cochlear implant.

AIM & OBJECTIVES: The study aimed to compare P1 latency and P1-N1 amplitude with receptive and expressive language ages in children using cochlear implant (CI) in one ear and a hearing aid (HA) in non-implanted ear. METHODS: The study included 30 children, consisting of 18 males and 12 females, aged between 48 and 96 months. The age at which the children received CI ranged from 42 to 69 months. A within-subject research design was utilized and participants were selected through purposive sampling. Auditory late latency responses (ALLR) were assessed using the Intelligent hearing system to measure P1 latency and P1-N1 amplitude. The assessment checklist for speech-language skills (ACSLS) was employed to evaluate receptive and expressive language age. Both assessments were conducted after cochlear implantation. RESULTS: A total of 30 children participated in the study, with a mean implant age of 20.03 months (SD: 8.14 months). The mean P1 latency and P1-N1 amplitude was 129.50 ms (SD: 15.05 ms) and 6.93 µV (SD: 2.24 µV) respectively. Correlation analysis revealed no significant association between ALLR measures and receptive or expressive language ages. However, there was significant negative correlation between the P1 latency and implant age (Spearman's rho = -0.371, p = 0.043). CONCLUSIONS: The study suggests that P1 latency which is an indicative of auditory maturation, may not be a reliable marker for predicting language outcomes. It can be concluded that language development is likely to be influenced by other factors beyond auditory maturation alone.

On the Difficulty Predicting Word Recognition Performance After Cochlear Implantation.

HYPOTHESIS: Preimplantation word scores cannot reliably predict postimplantation outcomes. BACKGROUND: To date, there is no model based on preoperative data that can reliably predict the postoperative outcomes of cochlear implantation in the postlingually deafened adult patient. METHODS: In a group of 228 patients who received a cochlear implant between 2002 and 2021, we tested the predictive power of nine variables (age, etiology, sex, laterality of implantation, preimplantation thresholds and word scores, as well as the design, insertion approach, and angular insertion depth of the electrode array) on postimplantation outcomes. Results of multivariable linear regression analyses were then interpreted in light of data obtained from histopathological analyses of human temporal bones. RESULTS: Age and etiology were the only significant predictors of postimplantation outcomes. In agreement with many investigations, preimplantation word scores failed to significantly predict postimplantation outcomes. Analysis of temporal bone histopathology suggests that neuronal survival must fall below 40% before word scores in quiet begin to drop. Scores fall steeply with further neurodegeneration, such that only 20% survival can support acoustically driven word scores of 50%. Because almost all cochlear implant implantees have at least 20% of their spiral ganglion neurons (SGNs) surviving, it is expected that most cochlear implant users on average should improve to at least 50% word recognition score, as we observed, even if their preimplantation score was near zero as a result of widespread hair cell damage and the fact that ~50% of their SGNs have likely lost their peripheral axons. These "disconnected" SGNs would not contribute to acoustic hearing but likely remain electrically excitable. CONCLUSION: The relationship between preimplantation word scores and data describing the survival of SGNs in humans can explain why preimplantation word scores obtained in unaided conditions fail to predict postimplantation outcomes.

Temporal Swelling Following Cochlear Implantation: Frequency, Treatment, and Outcomes.

OBJECTIVE: To investigate the frequency, treatment, and outcomes of postoperative delayed-onset swelling around cochlear implants. STUDY DESIGN: Retrospective, observational, nonrandomized group study. SETTING: Academic medical center. PATIENTS/INTERVENTIONS: Among 354 patients (516 ears) who underwent cochlear implantation (CI) at our hospital between May 2009 and October 2022, 329 (472 ears: 138 children [246 ears] and 191 adults [226 ears]) with a follow-up period of >3 months were included. MAIN OUTCOME MEASURES: Physical examination and computed tomography of the head were performed. RESULTS: In total, 5.5% (26/472 ears) had a history of delayed-onset swelling around the implant. This complication occurred in 9.8% (24/246 ears) of children and 0.9% (2/226 ears) of adults. The mean time to onset of swelling was 50 (range, 5.5-147) months following CI. In 60% (21/35) of the cases, the cause was unknown, whereas in 25.7% (9/35) and 11.5% (4/35) of cases, it was head trauma and acute inflammation, respectively. Conservative treatment (observation, antibiotics, and/or strong magnetic compression) was adapted in 91.4% (32/35) of cases. After conservative treatment, revision CI surgery was performed in one ear. Additionally, recurrent swelling was observed in 23.1% (6/26 ears) of swelling cases. CONCLUSIONS: The results suggest that delayed-onset swelling around implants occurs more frequently in children than in adults because of the higher incidence rates of head trauma and acute otitis media in children. In most cases, conservative treatment was adequate; however, careful follow-up is necessary. Our findings can serve as a reference for optimizing care and intervention options after CI.

On the Feasibility of Using Behavioral Listening Effort Test Methods to Evaluate Auditory Performance in Cochlear Implant Users.

Realistic outcome measures that reflect everyday hearing challenges are needed to assess hearing aid and cochlear implant (CI) fitting. Literature suggests that listening effort measures may be more sensitive to differences between hearing-device settings than established speech intelligibility measures when speech intelligibility is near maximum. Which method provides the most effective measurement of listening effort for this purpose is currently unclear. This study aimed to investigate the feasibility of two tests for measuring changes in listening effort in CI users due to signal-to-noise ratio (SNR) differences, as would arise from different hearing-device settings. By comparing the effect size of SNR differences on listening effort measures with test-retest differences, the study evaluated the suitability of these tests for clinical use. Nineteen CI users underwent two listening effort tests at two SNRs (+4 and +8 dB relative to individuals' 50% speech perception threshold). We employed dual-task paradigms-a sentence-final word identification and recall test (SWIRT) and a sentence verification test (SVT)-to assess listening effort at these two SNRs. Our results show a significant difference in listening effort between the SNRs for both test methods, although the effect size was comparable to the test-retest difference, and the sensitivity was not superior to speech intelligibility measures. Thus, the implementations of SVT and SWIRT used in this study are not suitable for clinical use to measure listening effort differences of this magnitude in individual CI users. However, they can be used in research involving CI users to analyze group data.

[The value of HRCT in predicting cerebrospinal fluid gusher during cochlear implantation].

Objective:To investigate the predictive value of temporal bone high-resolution CT（HRCT） multiplanar reconstruction（MPR） for cerebrospinal fluid（CSF） gusher during cochlear implantation in patients with inner ear malformation. Methods:The clinical data of 33 patients（36 ears） with inner ear malformation who underwent cochlear implantation were retrospectively analyzed. The predictive value of HRCT for cerebrospinal fluid gusher during cochlear implantation was evaluated. Results:The width of the cochlear foramen（P=0.024, OR=1.735） and the diameter of the inner auditory meatus（P=0.022, OR=6.119） were independent risk factors for CSF gusher during cochlear implantation. The area under the curve（AUC） of cochlear foramen width in predicting intraoperative gusher was 0.851, the sensitivity was 93.33%, and the specificity was 61.90%. The AUC of the upper and lower diameter of the internal auditory canal for predicting intraoperative gusher was 0.848, the sensitivity was 80.00%, and the specificity was 80.95%. The AUC of cochlear foramen width combined with the upper and lower diameters of the internal auditory meatus for predicting intraoperative gusher was 0.930, the sensitivity was 80.00%, and the specificity was 95.24%. Conclusion:Based on temporal bone HRCT, the prediction model of cochlear foramen width combined with the upper and lower diameter of the internal auditory canal has crucial predictive value for the "gusher" during cochlear implantation in patients with inner ear malformation.

[Assessment of auditory perception of children with single-sided deafness after cochlear implantation].

Unilateral deafness will lead to the decline of children's speech recognition rate, language development retardation and spatial positioning ability, which will have many adverse effects on children's life and study. Cochlear implantation can help children rebuild binaural hearing, and systematic audiological evaluation after operation is particularly important for clinicians to evaluate the hearing recovery of children. In this study, a variety of commonly used audiological evaluation, testing processes and methods after cochlear implantation in children with unilateral deafness are described in detail, and the related research status and results are summarized.

[Cochlear implantation through retro-facial approach with congenital microtia malformation with facial nerve deformity: a case report].

The difficulty of cochlear implantation in patients with congenital microtia is usually increased due to the vague anatomical marks and facial nerve malformation. The common types of facial nerve malformation include facial nerve bony cover loss, aberrant position, and bifurcation malformation. Bifurcation malformation may obscure the oval window, press against stapes, and bifurcate in the vestibular window while obscuring the round window. It is important to correctly identify the facial nerve and choose a reasonable surgical approach to avoid postoperative complications. This article describes a case of profound sensorineural hearing loss due to facial nerve malformation in our institution. The patient underwent cochlear implantation through the retro-facial approach. There was no facial nerve injury or dysfunction symptoms such as facial paralysis and hemifacial spasm 2 years after the operation, and the cochlear implant works well. The score of the categories of the auditory performance（CAP） questionnaire was 7, and the score of the speech intelligibility rating（SIR） questionnaire was 4. When the round window cannot be exposed through the facial recess approach during surgery, the retro-facial approach is a feasible method. To avoid facial nerve injury, a thin-section CT of the temporal bone should be performed before the middle and inner ear surgery for patients with facial nerve malformation, and the intraoperative facial nerve monitor should be used to clarify the course of the facial nerve to avoid injury.

Cochlear implantation in patients with Streptococcus suis meningitis: clinical characteristics and postoperative evaluation.

BACKGROUND: Hearing loss is a common sequala of Streptococcus suis (S. suis) meningitis, but few have addressed cochlear implantation (CI) candidates with S. suis meningitis. OBJECTIVES: To assess the clinical characteristics and CI postoperative outcomes in S. suis meningitis patients. MATERIAL AND METHODS: Eight S. suis meningitis patients underwent CI at Sun Yat-sen Memorial Hospital between 2020 and 2023. Control groups included (1) non-Suis meningitis patients (n = 12) and (2) non-meningitis patients (n = 35). Electrode impedances and neural response telemetry (NRT) thresholds were recorded at one month after surgery. The auditory performance-II (CAP) and speech intelligibility rating (SIR) were recorded at the last visit. RESULTS: CAP scores of S. suis meningitis patients were significantly lower than those of non-Suis meningitis and non-meningitis patients (p = .019; p<.001). And NRT thresholds of S. suis meningitis patients were higher than those of non-Suis meningitis and non-meningitis patients (p = .006; p = .027). CONCLUSIONS AND SIGNIFICANCE: It is recommended for S. suis meningitis CI candidates to undergo CI promptly after controlling infection, preferably within four to six weeks. CI users with S. suis meningitis tend to exhibit suboptimal hearing rehabilitation outcomes, possibly associated with the more severe damage on spiral ganglion cells after S. suis meningitis.