It is unknown how electrode array position in the cochlea influences long-term hearing preservation for cochlear implant (CI) recipients with preserved low-frequency hearing after surgery. The aim of this study was to evaluate the influence of electrode insertion depth relative to regions of post-operative acoustic hearing and hearing preservation ≥ 1 year after CI activation. A retrospective review of adult CI recipients of a straight electrode array from 2017 to 2022 with functional acoustic hearing preservation (≤ 80 dB HL at 250 Hz) at device activation was performed. Proximity was quantified as the angular insertion depth (AID) of the most apical contact relative to the region of preserved functional acoustic hearing. Positive values indicate placement within the functional acoustic region; negative values indicate placement basal to the functional acoustic region. Low-frequency pure tone average (LFPTA) was queried from the preoperative, device activation, and annual post-activation visits. Stepwise regression analyzed whether proximity, AID, age, biological sex, and pre-operative LFPTA were significant predictors for change in unaided hearing thresholds. One hundred and six CI recipients met inclusion criteria. AID ranged from 330° to 717° (mean 513°, SD 79°). Proximity values ranged from -183° to 442° (mean 35°, SD 110°). None of the reviewed independent variables, including proximity, significantly predicted unaided hearing threshold shifts at the 1-year or the ≥ 3-year visits (p ≥ 0.128). Deeper insertion depths and electrode array placement within the functional acoustic hearing region did not predispose CI recipients to delayed loss of residual hearing.

To investigate changes in hearing sensitivity post cochlear implantation with MED-EL and Advanced Bionics (AB) lateral wall electrode arrays, with a focus on characterizing delayed onset hearing loss (doHL) and concurrent electrode impedance changes. A retrospective review of 96 adult cochlear implant (CI) recipients (101 ears; MED-EL: 51, AB: 50). Hearing sensitivity was assessed using the low-frequency pure tone average (LFPTA; 125, 250, 500Hz). Immediate decrements in hearing sensitivity were considered separately from delayed decrements. The incidence, degree, and timing of doHL were characterized. Electrode impedances were considered for individuals with doHL compared with those with stable hearing. Median immediate hearing loss was 19dB across manufacturers. At initial activation, 73% of subjects had functional (LFPTA <80dB HL) hearing. When all subjects with variable postoperative time periods were included, the incidence of doHL was 27% with a median degree of 24dB. The median time doHL occurred was 76 weeks. Most (79%) subjects were categorized with gradual decrements rather than precipitous. No MED-EL subjects with doHL experienced concurrent impedance changes; 3 AB subjects did. Incidence of doHL rose to 31% and 44% when considering the subset of subjects with at least 1 year and 2 years of postoperative follow-up, respectively. DoHL that was precipitous in nature was observed less frequently than previously reported. Although precipitous hearing loss tended to occur shortly after surgery, most instances of doHL occurred later than anticipated. The absence of concurrent impedance changes for recipients of MED-EL electrode arrays is consistent with previous reports.

Robotic-assisted electrode array (EA) insertion is a promising technique that may enhance preservation of residual acoustic hearing after cochlear implant (CI) surgery. The purpose of this study is to evaluate the impact of robotic-assisted EA insertion on rates of delayed-onset hearing loss (DOHL). Sixty (Advanced Bionics [AB]: 30, MED-EL: 30) adult patients underwent CI surgery with manual EA insertion and 29 (AB: 13, MED-EL: 16) with robotic-assisted insertion using the iotaSOFT system. The primary outcome variable was longitudinal change in low frequency pure-tone average (LFPTA). DOHL was defined as a decrease in LFPTA of > 10 dB compared to previous best postoperative LFPTA. Twenty-two (37%) out of the 60 subjects in the manual cohort and two (7%) out of the 29 subjects in the robotic-assisted cohort had DOHL over the entire length of available follow-up (p = 0.002, Fisher's exact test, two-tailed). When evaluating DOHL results for subjects who had LFPTA data at 12 months (±4 weeks) post initial activation, 11 (29%) out of the 38 (AB: 15, MED-EL: 23) subjects in the manual cohort and zero (0%) out of the 18 (AB: 8, MED-EL: 10) subjects in the robotic-assisted cohort had DOHL (p = 0.011, Fisher's exact test, two-tailed). The number needed to treat was 4. Robotic-assisted EA insertion is associated with a clinically meaningful reduction in rates of DOHL. Preservation of residual acoustic hearing is a critical goal in CI surgery, and robotic-assisted EA insertion contributes towards achieving this goal.

To compare hearing preservation (HP) outcomes between ears for adult sequential bilateral cochlear implant (CI) recipients. Within-subject, retrospective cohort. Tertiary referral CI center. Sixty adults with preoperative functional acoustic hearing [low-frequency pure-tone average (LFPTA; 125, 250, and 500 Hz) ≤80 dB HL] were implanted with the same electrode array in both ears. Sequential bilateral cochlear implantation from 2012 to 2022. Initial (1mo) and long-term (12mo) HP outcomes between ears were assessed by comparing the LFPTA shift in the first and second implanted ear. Correlations between LFPTA shift in the first and second implanted ear at 1 month ( rs = 0.221, P = 0.090) and 12 months ( rs = 0.234, P = 0.123) were weak and nonsignificant. However, a multilevel linear mixed-effects model demonstrated greater LFPTA shifts in the second implanted ear when compared with the first, with a mean difference of 6.3 dB HL (95% CI: 0.2-12.4, P = 0.048). In addition, the model showed that HP declined during the first 12 months following implantation, and younger patients had greater LFPTA shifts over time ( p interaction = 0.012). There were no significant associations between LFPTA shift and preoperative LFPTA, biological sex, electrode array design, or postoperative steroid use. In the present sample, HP in the first implanted ear was poorly predictive of the outcome in the second ear. Substantial variability in outcomes between ears could indicate that subtle differences in surgical technique and insertion dynamics have a relatively larger impact on HP than patient-specific factors.

To determine whether there is seasonal variation in the audiogram data of patients with autoimmune inner ear disease (AIED). Retrospective chart review. Academic. One hundred forty-one adult patients with a diagnosis of AIED from January 2010 to June 2023 were included. Audiometry. For patients' better- and worse-hearing ears, as defined by audiogram metrics, pure tone average (PTA), high-frequency PTA (HFPTA), low-frequency PTA (LFPTA), and average word discrimination score (WDS) were calculated for each season. For better-hearing ears, hearing was, on average, 0.9dB worse in the summer than in the winter (P=0.04). High-frequency hearing was 1.18dB worse in the spring (P=0.047) and 1.11dB worse in the summer (P=0.03) compared with the winter. Low-frequency hearing was 0.68dB worse in the spring (P=0.04) and 0.89dB worse in the summer (P=0.04) than in the winter. For worse-hearing ears, low-frequency hearing was 1.10dB worse in the spring (P=0.01), 1.83dB worse in the summer (P=0.0003), and 1.57dB worse in the autumn (P=0.005) compared with the winter. WDS showed no significant differences across seasons. However, more patients were found to have "flares," sudden decreases in hearing or increases in subjective symptoms, as indicated by patient complaints and prednisone prescriptions, in the winter compared with other seasons. Control patients showed no seasonal variation. Paired t tests, repeated measures ANOVA, and Bonferroni post hoc tests were used. AIED audiogram changes and flares may be influenced by complex interactions between environmental factors. The implications of seasonal factors as a consideration in the symptoms and treatment of AIED warrant further study.

This study investigates the relationship between hepatitis A and B vaccinations and hearing loss, along with Pure Tone Average (PTA). Data from 5553 U.S. adults aged 20–69 in National Health and Nutrition Examination Survey (NHANES) cycles 2011–2012 and 2015–2016 were analyzed using multivariate regression to assess vaccination status effects on hearing loss and PTA. After adjustment for confounders, ≥ 2 doses of hepatitis A vaccine showed a significant inverse association with speech-frequency hearing loss (OR 0.76, 95% CI 0.60–0.97). ≥ 3 doses of hepatitis B vaccine correlated positively with right ear low-frequency PTA (β 1.22, 95% CI 0.24–2.20). Subgroup analyses indicated that hepatitis A vaccine benefits females and Hispanic individuals, while hepatitis B impacts are more pronounced in non-Hispanic whites, married individuals, and smokers. Mediation analysis excluded antibody mediation in these associations. Adequate hepatitis A vaccination protects against speech-frequency hearing loss, whereas hepatitis B vaccination may increase low-frequency PTA in the right ear. These findings highlight the importance of hearing health monitoring in specific populations and warrant further research into underlying mechanisms.

Objective(s):Robotic-assisted electrode array (EA) insertion is a promising technique that may enhance hearing preservation in cochlear implant (CI) surgery. The purpose of our study is to understand the extent to which robotic-assisted EA insertion improves hearing preservation.Methods:Twenty-four adult patients underwent CI surgery with manual EA insertion and 27 adult patients underwent CI surgery with robotic-assisted EA insertion using the iotaSOFT system. The EAs used included the Flex 20/24/26. The primary outcome variable was low frequency pure-tone average (LFPTA), defined as mean audiometric threshold at 125, 250, and 500 Hz. This was measured preoperatively, at initial activation (within 4 weeks of surgery), and subsequently at 2 weeks, 3 months, 6 months, and 1 year. Functional acoustic hearing was defined as LFPTA < 80 dB HL.Results:Seventeen out of 24 patients (71%) in the manual insertion group and 23 out of 27 patients (85%) in the robotic-assisted EA insertion group had preserved functional acoustic hearing (< 80 dB HL) up till 1 year (Fisher’s exact test (two-tailed) is not statistically significant, p = 0.31). The number needed to treat with robotic-assisted EA insertion to prevent one additional negative outcome of loss of functional acoustic hearing would be 7 (1/0.14).Conclusion:Robotic-assisted EA insertion is associated with improved hearing preservation over 1 year compared with manual insertion. Hearing preservation leads to improved outcomes and therefore every effort should be made to preserve the delicate structure and function of the cochlea during EA insertion. Robotic-assisted EA insertion advances that objective.Level of Evidence:III (cohort study).

Speech Performance Following Intraoperative Correction of Cochlear Implant Electrode Array Tip Fold-Overs.

To report hearing preservation (HP) outcomes based on anticoagulation/antiplatelet use (blood thinner, BT) following cochlear implantation (CI). Retrospective cohort. Tertiary referral center. Three hundred twenty-six adults (361 ears: no BT = 210, BT held = 86, BT continued = 65) implanted between 2012 and 2021 with preoperative low-frequency pure-tone average (LFPTA) of 65 dB HL or better. Postoperative HP, defined as LFPTA ≤80 dB HL, at 1, 3, 6, and 12 months. Compared to no BT, the BT held and continued groups were older (60.6 vs 72.7 vs 73.0 yrs, p < 0.001) and had diabetes (10% vs 28% vs 22%, p < 0.001). Electrode type, steroid use, surgical approach, and preoperative LFPTA were equivalent among groups. Postoperative HP rates were significantly higher for no BT than the BT held and continued groups at 1 month (62% vs 48% vs 43%, p = 0.008), with equivalent results at 3, 6, and 12 months. When patients were stratified by BT type, there were no significant differences in HP outcomes. On multivariate analysis, BT status was not a significant predictor of HP rates at 1 or 12 months. Younger age (OR 0.95, 95% CI 0.94-0.97, p < 0.001) was the only significant predictor of 1- but not 12-month HP. BT use, regardless of whether held for surgery, was associated with inferior early HP outcomes. After controlling for age, BT status was not a significant predictor of HP, suggesting inherently poorer cochlear health in patients who are on BTs.

To evaluate whether electrocochleography (ECochG)-guided pull-back of the perimodiolar electrode improves perimodiolar proximity, hearing preservation (HP), and cochlear implant performance. Prospective cohort study. Tertiary referral center. 77 adult CI recipients with residual acoustic hearing (low-frequency pure-tone average of 125, 250, 500 Hz; LFPTA ≤80 dB HL). Unilateral implantation, comparing conventional insertion (N = 31) with ECochG-guided electrode pull-back (N = 46). The guided method uses active ECochG from the apical electrode during adjustment and post-insertion electrode sweep to identify "tonotopic response" (defined as maximum response for 250 Hz at most apical electrode on electrode sweep). Perimodiolar proximity (wrapping factor on postoperative CT); speech-perception testing (CNC, AzBio in noise +10 dB SNR); and HP at 3 and 6 months post-activation (defined as LFPTA ≤80 dB HL). Of the subjects undergoing ECochG-guided insertion, 36 required pull-back based on lack of tonotopic responses, whereas the remaining 10 exhibited "optimal responses" post-insertion, needing no adjustment. Improved perimodiolar proximity was achieved with the ECochG-guided method (mean wrapping factor difference, 6.4; 95% CI, 3.0-9.9). The LFPTA shift was smaller using ECochG-guided pull-back when compared with conventional insertion by 17.0 dB HL (95% CI, 8.3-25.7) and 14.8 dB HL (95% CI, 6.5-23.2) at 3 and 6 months, respectively. Forty percent achieved HP using ECochG-guided pull-back versus 27.5% without. There was no difference in CNC scores among both cohorts, but AzBio in noise scores at 6 months was improved in the ECochG-guided pull-back cohort (mean difference, 19.1%; 95% CI, 5.8-32.4). ECochG-guided pull-back increased perimodiolar proximity and HP rates. Although there was no difference in speech perception performance in quiet, a significant improvement was noted in noisy conditions, potentially attributable to HP and the utilization of hybrid stimulation.

To provide evidence to use an extended frequency pure tone average to screen for cochlear implant evaluation candidates as recommended by the American Cochlear Implant Alliance. Additionally, to determine whether traditional low frequency, high or low frequency, high frequency, or extended frequency pure tone average most accurately predicts cochlear implant candidates based on speech perception scores from aided AzBio sentence testing or aided consonant-nucleus-consonant (CNC) testing. Adults from a tertiary care center who completed aided sentence testing during cochlear implant evaluation between 2014 and 2024 were assessed. Pure tone averages at low, high, low or high, and extended frequency ranges were evaluated with individual ear's aided AzBio or aided CNC scores as an outcome. Sensitivity, specificity, negative predictive value, and positive predictive value were assessed and compared using a paired study design. There were 675 observations from 363 patients with AzBio as an outcome variable and 665 observations from 364 patients with CNC scores as an outcome variable. High or low frequency achieved the highest sensitivity at 96.3% AzBio as an outcome and 95.6% with CNC as an outcome, which was significantly better than low frequency (p < 0.001). Low frequency achieved the best specificity at 63.6% with AzBio as an outcome 76.9% with CNC as an outcome. Extended frequency pure tones resulted in greater sensitivity in predicting CI candidates compared with the traditionally used low frequency pure tone average. Screening with wider frequency values will lead to a greater number of patients being identified for a cochlear implant evaluation. 3 Laryngoscope, 135:2100-2106, 2025.

The present study aimed to investigate the relationship between auditory thresholds and Lifestyle Induced Hearing Loss Risk Questionnaire (LIHLRQ). In this study 60 participants in the age range of 19 to 27 years (mean age = 21.59 years, SD = 1.50) with normal hearing sensitivity were categorized in three hearing loss risk groups (no risk, mild risk and moderate risk) based on LIHLRQ scores. The auditory profile at low frequency pure-tone average (LFPTA) and extended high frequency pure-tone average (EHFPTA) of the participants in the three risk groups were compared with respective LIHLRQ scores. Kruskal-Wallis test findings indicated that there were significant differences across the three groups based on LIHLRQ scores. One way ANOVA test revealed that the LFPTA- Right ear was lowest for the participant categorized under ‘no risk group. Further, the thresholds were highest for the group of participants with moderate risk. Similar trend was also noted for Low frequency PTA-Left ear. No significant differences were seen with respect to extended high frequency PTA among the three groups. The present study shows that there is a significant difference in LIHLRQ scores among participants with no risk, mild risk and moderate risk for hearing loss. It also shows that there exist a significant difference in Low frequency pure tone average of individuals with no risk for hearing loss and individuals with risk for hearing loss. Hence it can be concluded that LIHLRQ scores provide early indications of changes in hearing thresholds.

ObjectiveTo compare hearing preservation outcomes between lateral wall and perimodiolar electrode arrays for cochlear implant patients.Study DesignRetrospective cohort study.SettingA large Western Australian cochlear implant clinicMethodsA total of 311 adult cochlear implant recipients (321 ears) implanted between 2017 and 2022 were included. Of these, 174 presented with postlingual hearing loss and preoperative functional low-frequency hearing. The change in low-frequency pure-tone average was assessed as the difference between preoperative to 3-, 6-, and 12-months postoperative measurements. Data were analyzed through linear mixed-effects modeling and one-way ANOVA.ResultsPreoperative low-frequency, pure-tone average was higher for those implanted with perimodiolar compared with lateral wall electrodes (P < .05). The linear mixed-effects model revealed that change in low-frequency pure-tone average at all postoperative timepoints was similar between lateral wall and perimodiolar electrodes (P > .05).ConclusionThere were similar changes in residual postoperative hearing between all electrode types when controlling for preoperative low-frequency hearing and age implanted. These data suggest that newer, thinner perimodiolar and lateral wall electrodes could be considered for individuals with greater levels of preoperative low-frequency hearing.

Electric-acoustic stimulation (EAS) provides cochlear implant (CI) recipients with preserved low-frequency acoustic hearing in the implanted ear affording auditory cues not reliably transmitted by the CI including fundamental frequency, temporal fine structure, and interaural time differences (ITDs). A prospective US multicenter clinical trial was conducted examining the safety and effectiveness of a hybrid CI for delivering EAS. Fifty-two adults (mean age 59.9 yr) were enrolled in the study and followed up to 5 years postactivation. Testing included unaided and aided audiometric thresholds, speech perception (Consonant-Nucleus-Consonant [CNC] words in quiet and AzBio sentences +5 dB SNR), and patient-reported outcomes (Speech, Spatial, and Qualities of Hearing Scale). Functionally aidable hearing, defined as low-frequency pure-tone average (125-500 Hz) <80 dB HL, was maintained for 77% of patients through 1 year, with 66.7% maintaining through 5 years. Speech perception was significantly improved at all postoperative timepoints compared with preoperative performance with hearing aid(s), and patient-reported outcomes indicated significantly improved subjective speech understanding, spatial hearing, and sound quality. Participants with preserved acoustic hearing using EAS reported significantly higher subjective spatial hearing and sound quality than participants with electric-only hearing in the implanted ear. Patients with high-frequency hearing loss demonstrate significant long-term benefit with a hybrid CI including high rates of functional hearing preservation, significantly improved speech perception, and subjective patient-reported outcomes. EAS with binaural acoustic hearing affords benefit for subjective spatial hearing and sound quality beyond CI listening configurations using monaural acoustic hearing.

To examine the effects of scala tympani (ST) volume, cochlear duct length (CDL), and angular insertion depth (AID) on low-frequency hearing preservation for cochlear implant (CI) recipients of lateral wall electrode arrays. A retrospective review identified 45 adult CI recipients of 24-, 28-, or 31.5-mm lateral wall electrode arrays with preoperative unaided hearing thresholds ≤45 decibel hearing level (dB HL) at 250 Hz. All patients underwent preoperative and postoperative computed tomography to evaluate cochlear morphology and electrode array position. A linear mixed effects model evaluated effects of ST volume, CDL, AID, preoperative low-frequency pure-tone average (LFPTA; 125, 250, and 500 Hz), age at surgery, and biological sex on the postoperative change in LFPTA at activation and 6 months post-activation. There were significant main effects of ST volume (p = 0.044), age (p = 0.028), and biological sex (p = 0.003), indicating better low-frequency hearing preservation for CI recipients with larger ST volumes, younger age at surgery, and female biological sex. Although CDL positively correlated with ST volume (r = 0.74, p < 0.001), there was no significant main effect of CDL (p = 0.367). A broad range in AID of the most apical electrode contact was observed (301.4°-681.8°); however, there was no significant main effect of AID on low-frequency hearing preservation (p = 0.700). During the initial 6 months following implantation, intrinsic factors such as cochlear morphology may have a greater impact on low-frequency hearing preservation than apical positioning of a flexible lateral wall electrode array when using soft surgical techniques. 3 Laryngoscope, 2024.

ObjectiveTo examine the impact of slight to mild hearing loss in children by studying its association with academic performance and behavioral problems.MethodsThis study was embedded within a prospective birth cohort in Rotterdam, the Netherlands. Participants underwent audiometric and behavioral evaluations between ages 9–11 (April 2012–October 2015) and 13–15 (May 2017–September 2019). At 13–15, a multiple linear regression was conducted to explore the relationship between hearing acuity and both academic and behavioral outcomes. A cross‐lagged analysis using data from ages 9 to 11 investigated bidirectional associations between hearing loss and behavioral problems.ResultsThe cross‐sectional part of the study involved 4688 participants at the age of 13–15 years. The relative risk for children with slight to mild hearing loss of being placed in a lower educational level compared with the highest level was 1.52 (95% confidence interval (CI) [1.14, 2.02]). Among boys, elevated high‐frequency pure‐tone average (HPTA) was associated with a higher total problem score (per 1 dB HPTA: β = 0.01; 95% CI [0.00, 0.02]). For girls, elevated low‐frequency pure‐tone average (LPTA) was associated with a higher attention problem score (per 1 dB LPTA: β = 0.02; 95% CI [0.01, 0.02]). Cross‐lagged effects showed that participants with increased pure‐tone averages in low frequencies at 9–11 years had more social problems at ages 13–15 years (Z‐score difference: 0.01; 95% CI [0.01, 0.02]).ConclusionElevated hearing thresholds in slight to mild hearing loss were linked to poorer academic performance and increased behavioral problems.Level of Evidence2 (prospective cohort study) Laryngoscope, 135:1511–1519, 2025

To prospectively evaluate the association between hearing preservation after cochlear implantation (CI) and intracochlear electrocochleography (ECochG) amplitude parameters. Multi-institutional, prospective randomized clinical trial. Ten high-volume, tertiary care CI centers. Adults (n = 87) with sensorineural hearing loss meeting CI criteria (2018-2021) with audiometric thresholds of ≤80 dB HL at 500 Hz. Participants were randomized to CI surgery with or without audible ECochG monitoring. Electrode arrays were inserted to the full-depth marker. Hearing preservation was determined by comparing pre-CI, unaided low-frequency (125-, 250-, and 500-Hz) pure-tone average (LF-PTA) to LF-PTA at CI activation. Three ECochG amplitude parameters were analyzed: 1) insertion track patterns, 2) magnitude of ECochG amplitude change, and 3) total number of ECochG amplitude drops. The Type CC insertion track pattern, representing corrected drops in ECochG amplitude, was seen in 76% of cases with ECochG "on," compared with 24% of cases with ECochG "off" ( p = 0.003). The magnitude of ECochG signal drop was significantly correlated with the amount of LF-PTA change pre-CI and post-CI ( p < 0.05). The mean number of amplitude drops during electrode insertion was significantly correlated with change in LF-PTA at activation and 3 months post-CI ( p ≤ 0.01). ECochG amplitude parameters during CI surgery have important prognostic utility. Higher incidence of Type CC in ECochG "on" suggests that monitoring may be useful for surgeons in order to recover the ECochG signal and preventing potentially traumatic electrode-cochlear interactions.

AI model for predicting adult cochlear implant candidacy using routine behavioral audiometry

Several lines of evidence have suggested that steeply sloping audiometric losses are caused by hair cell degeneration, while flat audiometric losses are caused by strial atrophy, but this concept has never been rigorously tested in human specimens. Here, we systematically compare audiograms and cochlear histopathology in 160 human cases from the archival collection of celloidin-embedded temporal bones at the Massachusetts Eye and Ear. The dataset included 106 cases from a prior study of normal-aging ears, and an additional 54 cases selected by combing the database for flat audiograms. Audiogram shapes were classified algorithmically into five groups according to the relation between flatness (i.e., SD of hearing levels across all frequencies) and low-frequency pure-tone average (i.e., mean at 0.25, 0.5, and 1.0 kHz). Outer and inner hair cell losses, neural degeneration, and strial atrophy were all quantified as a function of cochlear location in each case. Results showed that strial atrophy was worse in the apical than the basal half of the cochlea and was worse in females than in males. The degree of strial atrophy was uncorrelated with audiogram flatness. Apical atrophy was correlated with low-frequency thresholds and basal atrophy with high-frequency thresholds, and the former correlation was higher. However, a multivariable regression with all histopathological measures as predictors and audiometric thresholds as the outcome showed that strial atrophy was a significant predictor of threshold shift only in the low-frequency region, and, even there, the contribution of outer hair cell damage was larger.SIGNIFICANCE STATEMENT Cochlear pathology can only be assessed postmortem; thus, human cochlear histopathology is critical to our understanding of the mechanisms of hearing loss. Dogma holds that relative damage to sensory cells, which transduce mechanical vibration into electrical signals, versus the stria vascularis, the cellular battery that powers transduction, can be inferred by the shape of the audiogram, that is, down-sloping (hair cell damage) versus flat (strial atrophy). Here we quantified hair cell and strial atrophy in 160 human specimens to show that it is the degree of low-frequency hearing loss, rather than the audiogram slope, that predicts strial atrophy. Results are critical to the design of clinical trials for hearing-loss therapeutics, as current drugs target only hair cell, not strial, regeneration.

Does labyrinthectomy have an impact on hearing in the contralateral ear during long-term follow-up?