Transcutaneous and percutaneous bone conduction sound propagation in single-sided deaf patients and cadaveric heads.

OBJECTIVE: To investigate transcranial transmission (TT) and the dampening effect of the skin in patients and cadaver heads. DESIGN: In patients a pure tone bone conduction audiogram for ipsilateral and contralateral stimulation was performed. The TT was defined as the difference between ipsilateral and contralateral hearing thresholds. In cadaver heads ipsilateral and contralateral promontory motion was measured using a three-dimensional Laser Doppler Vibrometer system. STUDY SAMPLE: Seven single-sided deaf patients fitted with a Baha® Connect, fifteen single-sided deaf patients without a bone conduction hearing aid and five Thiel-embalmed cadaver heads were included. RESULTS: The TT decreased with increasing frequency in patients and cadaver heads. No significant difference was seen between patients and cadaver heads. Measurements on patients and cadaver heads showed increasing skin attenuation with increasing frequency. However, the dampening effect was 3-12 dB higher in patients than in cadavers at all frequencies. CONCLUSION: The TT was not significantly different for patients compared to cadaver heads. The value of promontory motion to estimate TT in patients need to be further evaluated. The skin attenuates a BC stimulus by 10-20 dB in patients and by a smaller amount in cadaver heads, probably due to changes in the properties of the Thiel-conserved skin.

[The professional ear user-implications for the prevention, diagnosis, and treatment of ear diseases]. / Der "Professional Ear User" ­ Implikationen für die Prävention, Diagnostik und Therapie von Ohrerkrankungen.

BACKGROUND: Perfect hearing is crucial to the practice of various professions, such as instrument makers, musicians, sound engineers, and other professions not related to music, such as sonar technicians. For people of these occupational groups, we propose the term "professional ear user" (PEU) in analogy to "professional voice user". PEUs have special requirements for their hearing health, as they have well-known above-average auditory perceptual abilities on which they are professionally dependent. OBJECTIVE: The purpose of this narrative review is to summarize selected aspects of the prevention, diagnosis, and treatment of ear disorders in PEUs. RESULTS AND CONCLUSION: Prevention of hearing disorders and other ear diseases includes protection from excessive sound levels, avoidance of ototoxins and nicotine, and a safe manner of cleaning the outer auditory canal. Diagnosing hearing disorders in PEUs can be challenging, since subclinical but relevant changes in hearing cannot be reliably objectified by conventional audiometric methods. Moreover, the fact that a PEU is affected by an ear disease may influence treatment decisions. Further, physicians must be vigilant for non-organic ear diseases in PEUs. Lastly, measures to promote comprehensive ear health in PEUs as part of an educational program and to maintain ear health by means of a specialized otolaryngology service are discussed. In contrast to existing concepts, we lay the attention on the entirety of occupational groups that are specifically dependent on their ear health in a professional setting. In this context, we suggest avoiding a sole focus on hearing disorders and their prevention, but rather encourage the maintenance of a comprehensive ear health.

Influence of Semicircular Canal Dehiscence on Cochlear Implant Outcome.

INTRODUCTION: Semicircular canal dehiscence (SCD) is defined as a defect of the bone overlying the semicircular canal. It has a relatively high prevalence of 3% in the general population, which makes it likely that a certain number of patients receiving a cochlear implant (CI) would have it. However, little is known about the influence of SCD on the CI outcome. Therefore, the aim of this study was to determine the influence of SCD on CI outcome with regard to short- and long-term word perception and hearing preservation. METHODS: This study was a retrospective analysis of postoperative word perception ability in the electric-only condition after 6, 12, and ≥18 months and of hearing preservation 4 weeks after surgery in CI recipients with and without SCD. All patients received a preoperative 1.5- or 3-tesla magnetic resonance imaging. RESULTS: Fifty-five patients were included. Forty-eight patients (87%) had no SCD, and 7 patients (13%) had SCD. Mean postoperative word perception scores were 66% in the non-SCD group versus 50% in the SCD group (p = 0.17) after 6 months, 74 versus 64% (p = 0.28) after 12 months, and 77 versus 73% (p = 0.62) after 18 or more months. The mean postoperative hearing loss in patients with functional residual hearing before surgery (n = 34) was 22 dB in the non-SCD group versus 31 dB in the SCD group (p = 0.15). CONCLUSIONS: CI outcome is comparable between recipients without and with SCD. Specifically, hearing preservation rate and word perception ability in the electric-only condition seem not affected by SCD. The rate of progress of word perception ability in the first 12 months after cochlear implantation is not influenced by SCD.

Simultaneous Intra- and Extracochlear Electrocochleography During Electrode Insertion.

OBJECTIVES: (1) To correlate simultaneously recorded intra- and extracochlear electrocochleography (ECochG) signals during electrode insertion into the cochlea, (2) to track changes in the ECochG signal during insertion and removal of an electrode, and (3) to correlate the findings with the preoperative residual hearing. We hypothesized that intracochlear ECochG recordings show signal changes not reflected in simultaneous extracochlear ECochG recordings. DESIGN: During cochlear implantation in human cochlear implant recipients, a short, slim, custom-made electrode was inserted and removed in a stepwise manner. At each step, ECochG recordings were simultaneously recorded by an extracochlear electrode near the round window and via the inserted electrode. The acoustic stimulus was a 500 Hz tone burst at 110 to 130 dB SPL. RESULTS: The mean amplitude difference between intra- and extracochlear ongoing ECochG responses was 14 dB (range 9 to 24 dB; n = 10) at the beginning of insertion. Intracochlear ECochG responses were larger in all cases. Extracochlear ECochG responses remained stable while intracochlear recordings showed large variations regarding amplitude and phase during the electrode array insertion. Intracochlear signal changes during insertion were reversible with retraction of the electrode. There were only weak to moderate (rs = 0.006 to 0.4), nonsignificant correlations of residual preoperative hearing with maximum amplitudes and amplitude changes during electrode insertion and removal in intracochlear recordings. CONCLUSIONS: Signals in intracochlear ECochG recordings are reliably larger than ECochG signals recorded simultaneously from an extracochlear location. Intracochlear ECochG recordings show reversible amplitude and phase changes during insertion, not reflected in simultaneous extracochlear ECochG recordings. Such changes are most likely due to the movement of the recording electrode in relation to the signal generators. Residual high-frequency hearing is associated with larger ECochG signal amplitudes. Modeling of expected intracochlear ECochG changes during electrode insertions may allow detection of cochlear trauma in the future.

Endolymphatic hydrops mimicking obstructive Eustachian tube dysfunction: preliminary experience and literature review.

PURPOSE: Aural fullness is a common symptom of middle ear diseases, most importantly Eustachian tube dysfunction (ETD). Yet, aural fullness may also be caused by inner ear disorders, such as hydropic ear diseases. Here, we report our experience with endolymphatic hydrops (EH) mimicking ETD. Furthermore, we review the literature related to (i) EH as a differential diagnosis of symptoms suggesting ETD and (ii) the pathophysiology and treatment of aural fullness due to inner ear disorders. METHODS: We retrospectively included adult patients with aural fullness as chief complaint and radiographically diagnosed EH. Hearing and Eustachian tube function were assessed using audiometry, tympanometry, and tubomanometry. Primarily suspected ETD was treated by balloon dilatation of the Eustachian tube (BDET). The endolymphatic space of the inner ear was imaged using gadolinium-enhanced MRI (Gd-MRI) including a 3D-real inversion-recovery sequence after intravenous gadolinium administration. RESULTS: We report three affected ears of two patients (two females, age 42 and age 51) with aural fullness as chief complaint. Audiometry of main speech frequencies was normal in all affected ears. In one ear, there was a type A tympanogram and in two ears, there was a type B tympanogram. In both patients, medical treatment for ETD and BDET were unsuccessful. Gd-MRI of the inner ears revealed cochlear EH in 3/3 ears affected by aural fullness, but not in the unaffected ear. CONCLUSION: EH may underlay cases with aural fullness and could in these cases explain unsuccessful treatment for ETD. As ETD is often treated by invasive procedures, distinguishing ETD from EH as the underlying cause of aural fullness is important. Our findings raise the question whether Gd-MRI to rule out EH is indicated in patients with unexplained aural fullness, in particular after unsuccessful interventional treatment for ETD.

Distorted sound perception and subjective benefit after stapedotomy - a prospective single-centre study.

OBJECTIVE: To evaluate the quality of perceived sound after stapedotomy over a 1-year follow-up period focussing on incidence of dysacusis, particularly distorted sound perception (DSP). DSP was assessed by (i) determination of the frequencies and hearing level that such perceptions are elicited by pure tones (pure-tone-evoked distorted sound perception, PTE-DSP), a novel psychoacoustic measurement introduced in this paper, and (ii) assessment of patient-reported occurrence of DSP using the Amsterdam Post Operative Sound Evaluation (APOSE) questionnaire (APOSE-DSP). DESIGN: Prospective study. STUDY SAMPLE: Patients (n = 23) with otosclerosis undergoing stapedotomy. RESULTS: An air-bone gap of <20 dB was achieved in 100% of the patients. Three weeks postoperatively, 48% of the patients reported measured PTE-DSP and 39% of the patients experienced APOSE-DSP. The PTE-DSP significantly decreased during the 1-year follow-up period (p = 0.03). Postoperatively, APOSE-DSP was associated with a smaller benefit (improvement in air conduction; p = 0.03), yet, a lower bone conduction pure-tone average was associated with PTE-DSP (p = 0.006). CONCLUSIONS: DSP after stapedotomy is associated with a smaller benefit 3 months after stapedotomy. DSP commonly occur after stapedotomy, but decrease over time. This is important information to be included in patient counselling before stapedotomy.

Audiological monitoring in Swiss childhood cancer patients.

BACKGROUND: Full audiological monitoring is the best strategy to detect hearing loss early and to provide timely intervention in the absence of a clinical method of otoprotection. Full monitoring requires audiological evaluation before, and then during and after ototoxic cancer treatment. In a worldwide context of monitoring protocols that vary substantially, we analyzed the audiological monitoring of childhood cancer patients over the last decade across treatment centers in Switzerland. PROCEDURE: We retrospectively searched for audiological evaluations in all nine Swiss Pediatric Oncology Centers. We analyzed proportions of patients who had audiological monitoring and described type and timing of monitoring. We determined predictors of audiological monitoring using multivariable logistic regression and described time trends. RESULTS: We included 185 patients from the Swiss Childhood Cancer Registry diagnosed from 2005 to 2013 who had platinum chemotherapy and/or cranial radiation ≥30 Gray and who were alive at time of study. Less than half of children, 43%, had full audiological monitoring (before, during, and after treatment), while 72% were tested after cancer treatment. Nonstudy patients were less likely to have had monitoring in all phases of cancer treatment. Patients who received treatment with cisplatin or both platinum chemotherapy and cranial radiation were more likely to have had monitoring after treatment. Monitoring during and after treatment increased over the study period, but monitoring before treatment was insufficient in all time periods. CONCLUSIONS: Our population-based study indicates that audiological monitoring is insufficient in Switzerland, particularly for nonstudy patients. Clinicians must become more aware of the importance of full audiological monitoring.

Dynamic Postural Stability and Hearing Preservation after Cochlear Implantation.

OBJECTIVES: (1) To assess dynamic postural stability before and after cochlear implantation using a functional gait assessment (FGA). (2) To evaluate the correlation between loss of residual hearing and changes in dynamic postural stability after cochlear implantation. METHODS: Candidates for first-sided cochlear implantation were prospectively included. The FGAs and pure-tone audiograms were performed before and 4-6 weeks after cochlear implantation. RESULTS: Twenty-three subjects were included. Forty-eight percent (n = 11) showed FGA performance below the age-referenced norm before surgery. One subject had a clinically relevant decrease of the FGA score after cochlear implantation. No significant difference between the mean pre- and postoperative FGA scores was detectable (p = 0.4). Postoperative hearing loss showed no correlation with a change in FGA score after surgery (r = 0.3, p = 0.3, n = 16). CONCLUSION: Single-sided cochlear implantation does not adversely affect dynamic postural stability 5 weeks after surgery. Loss of functional residual hearing is not correlated with a decrease in dynamic postural stability.

Radiological feature heterogeneity supports etiological diversity among patient groups in Meniere's disease.

We aimed to determine the prevalence of radiological temporal bone features that in previous studies showed only a weak or an inconsistent association with the clinical diagnosis of Meniere's disease (MD), in two groups of MD patients (n = 71) with previously established distinct endolymphatic sac pathologies; i.e. the group MD-dg (ES degeneration) and the group MD-hp (ES hypoplasia). Delayed gadolinium-enhanced MRI and high-resolution CT data were used to determine and compare between and within (affected vs. non-affected side) groups geometric temporal bone features (lengths, widths, contours), air cell tract volume, height of the jugular bulb, sigmoid sinus width, and MRI signal intensity alterations of the ES. Temporal bone features with significant intergroup differences were the retrolabyrinthine bone thickness (1.04 ± 0.69 mm, MD-hp; 3.1 ± 1.9 mm, MD-dg; p < 0.0001); posterior contour tortuosity (mean arch-to-chord ratio 1.019 ± 0.013, MD-hp; 1.096 ± 0.038, MD-dg; p < 0.0001); and the pneumatized volume (1.37 [0.86] cm3, MD-hp; 5.25 [3.45] cm3, MD-dg; p = 0.03). Features with differences between the affected and non-affected sides within the MD-dg group were the sigmoid sinus width (6.5 ± 1.7 mm, affected; 7.6 ± 2.1 mm, non-affected; p = 0.04) and the MRI signal intensity of the endolymphatic sac (median signal intensity, affected vs. unaffected side, 0.59 [IQR 0.31-0.89]). Radiological temporal bone features known to be only weakly or inconsistently associated with the clinical diagnosis MD, are highly prevalent in either of two MD patient groups. These results support the existence of diverse-developmental and degenerative-disease etiologies manifesting with distinct radiological temporal bone abnormalities.

Chudley-McCullough syndrome: case report and review of the neuroimaging spectrum.

We report on a child with Chudley-McCullough syndrome and re-evaluate the spectrum of imaging findings (in 15 previously reported patients) which appear to be variable and, to some extent, ambiguous in the literature. Magnetic resonance imaging of the brain revealed asymmetric colpocephaly with agenesis of the splenium corporis callosi, ribbon-like subcortical gray matter heterotopia along the cingulate gyri, malrotation of both hippocampi, and dysplasia of the cerebellum. Macrocrania together with sensorineural hearing loss, colpocephaly, and posterior or complete agenesis of the corpus callosum can be considered the hallmarks of the autosomal recessive Chudley-McCullough syndrome. These may be variably associated with interhemispheric arachnoid cyst, cortical dysplasia, gray matter heterotopia, and cerebellar dysplasia. While early support with hearing aids may lead to improved language and cognitive outcome, shunting of ventricular dilatation is not indicated in the Chudley-McCullough syndrome.

Subjective Sound Quality Detection (HISQUI) over Time after Vibrant Soundbridge Implantation.

BACKGROUND: To evaluate the long-term audiological outcomes combined with the Hearing Implant Sound Quality Index (HISQUI) after Vibrant Soundbridge (VSB) implantation. METHODS: Prospective recall cohort study of patients who received a VSB in a tertiary academic medical center between 1996 and 2017. Air conduction (AC) and bone conduction (BC), sound field thresholds in aided and unaided conditions, and speech discrimination in noise (Oldenburger sentence test) were measured. Postoperative results were compared with preoperative audiograms. Furthermore, the HISQUI was evaluated. RESULTS: Ten patients (eleven implants) were included, the mean follow up period was nine years. The mean AC threshold preoperatively was between 63 and 70 dB, and the BC was between 38 and 49 dB from 500 to 4000 Hz. In the free-field audiogram, the mean threshold was between 61 and 77 dB unaided vs. between 28 and 52 dB in the aided condition. The average signal to noise ratio (SNR) in the Oldenburger sentence test in the unaided condition was 10 dB ± 6.7 dB vs. 2 dB ± 5.4 dB in the aided condition. Three patients reported a good to very good hearing result, four patients a moderate, and three patients a poor hearing result. There was a significant association between the years of implantation and the HISQUI (p = 0.013), as well as a significant decrease by 14 HISQUI points per 10 dB SPL decline (SE 5.2, p = 0.023). There was a significant difference between the change of BC over the years and the HISQUI, as well as the number of years after implantation and the HISQUI. On average, per dB decrease in BC, the HISQUI decreases by 1.4 points, and every year after implantation the HISQUI decreases by 2.7 points. CONCLUSIONS: The aided threshold in free field and speech understanding in noise improved significantly with VSB. An increase over time of BC thresholds was observed as well as a decrease in HISQUI score. This decrease in BC thresholds over time may be due to presbycusis. Therefore, monitoring of these patients over time should be considered to discuss alternative hearing rehabilitation measures in a timely manner.

Implications of Phase Changes in Extracochlear Electrocochleographic Recordings During Cochlear Implantation.

OBJECTIVE: To assess the prevalence and implications of phase changes in extracochlear electrocochleography (ECochG) recordings during cochlear implantation. MATERIALS AND METHODS: Extracochlear ECochG recordings were performed before and after insertion of the cochlear implant (CI) electrode by a recording electrode placed on the promontory. Acoustic stimuli were tone bursts at 250, 500, 750, and 1,000 Hz. The pure tone average (PTA) was determined before and approximately 4 weeks after surgery. RESULTS: Extracochlear ECochG recordings in 69 ears of 68 subjects were included. At 250 Hz, the mean phase change was 43° (n = 50, standard deviation (SD) 44°), at 500 Hz 36° (n = 64, SD 36°), at 750 Hz 33° (n = 42, SD 39°), and at 1,000 Hz 22° (n = 54, SD 27°). Overall, in 48 out of 210 ECochG recordings a phase change of ≥45° (23%) was detectable. Ears with an amplitude drop >3 dB and a phase change ≥45° (n = 3) had a complete or near complete loss of residual cochlear function in all cases. A phase change of ≥90° in one recording was not associated with a larger amplitude change of the ECochG signal (1.9 dB vs. -0.9 dB, p = 0.1052, n = 69), but with a significantly larger postoperative hearing loss (17 dB vs. 26 dB, p = 0.0156, n = 69). CONCLUSIONS: Phase changes occur regularly in extracochlear ECochG recordings during cochlear implantation. Phase changes of ≥90° with or without amplitude changes in the ECochG signal are associated with a larger postoperative hearing loss and could therefore represent an independent marker for cochlear trauma or changes of inner ear mechanics relevant for the postoperative hearing outcome.

Hearing Loss in Cancer Patients with Skull Base Tumors Undergoing Pencil Beam Scanning Proton Therapy: A Retrospective Cohort Study.

To assess the incidence and severity of changes in hearing threshold in patients undergoing high-dose pencil-beam-scanning proton therapy (PBS-PT). This retrospective cohort study included fifty-one patients (median 50 years (range, 13-68)) treated with PBS-PT for skull base tumors. No chemotherapy was delivered. Pure tone averages (PTAs)were determined before (baseline) and after PBS-PT as the average hearing thresholds at frequencies of 0.5, 1, 2, and 4 kHz. Hearing changes were calculated as PTA differences between pre-and post-PBS-PT. A linear mixed-effects model was used to assess the relationship between the PTA at the follow-up and the baseline, the cochlea radiation dose intensity, the increased age, and the years after PBS-PT. Included patients were treated for chordoma (n = 24), chondrosarcoma (n = 9), head and neck tumors (n = 9), or meningioma (n = 3), with a mean tumor dose of 71.1 Gy (RBE) (range, 52.0-77.8), and a mean dose of 37 Gy (RBE) (range, 0.0-72.7) was delivered to the cochleas. The median time to the first follow-up was 11 months (IQR, 5.5-33.7). The PTA increased from a median of 15 dB (IQR 10.0-25) at the baseline to 23.8 (IQR 11.3-46.3) at the first follow-up. In the linear mixed-effect model, the baseline PTA (estimate 0.80, 95%CI 0.64 to 0.96, p ≤ 0.001), patient's age (0.30, 0.03 to 0.57, p = 0.029), follow-up time (2.07, 0.92 to 3.23, p ≤ 0.001), and mean cochlear dose in Gy (RBE) (0.34, 0.21 to 0.46, p ≤ 0.001) were all significantly associated with an increase in PTA at follow-up. The applied cochlear dose and baseline PTA, age, and time after treatment were significantly associated with hearing loss after proton therapy.

Prevalence of Endolymphatic Hydrops in Cochlear Implant Candidates with Idiopathic Profound Sensorineural Hearing Loss.

OBJECTIVE: To determine the prevalence of endolymphatic hydrops (EH) in cochlear implant (CI) candidates with idiopathic profound sensorineural hearing loss (SNHL) and its influence on the preservation of audiovestibular function after cochlear implantation. STUDY DESIGN: Prospective case series. SETTING: Tertiary referral center. PATIENTS: CI candidates with idiopathic progressive SNHL, but without classic EH-associated symptoms. INTERVENTIONS: Delayed intravenous gadolinium-enhanced inner ear fluid-attenuated inversion recovery magnetic resonance imaging as well as pure-tone audiograms, video head impulse tests, and vestibular evoked myogenic potentials before and 4 weeks after cochlear implantation. MAIN OUTCOME MEASURES: Prevalence of EH before cochlear implantation, audiovestibular function before and after surgery in hydropic and nonhydropic ears. RESULTS: Thirty-two ears in 16 CI candidates were included. Nine ears (28%) with EH were detected. Although preoperative hearing thresholds, utricular function, and semicircular canal function were not different between the two groups, saccular function was reduced in hydropic ears. Ten subjects received a unilateral CI. Of these, 3 (30%) showed EH on the implanted side. There was no difference regarding postoperative hearing loss between the two groups, but the results point toward a higher vulnerability of hydropic ears with respect to loss of otolith function after cochlear implantation. CONCLUSIONS: This is the first study showing that EH can be assumed in about one third of CI candidates with idiopathic profound SNHL, but no classic EH-associated symptoms. Preliminary results suggest that EH has no influence on the preservation of cochlear function but could be a risk factor for loss of otolith function after cochlear implantation.

Cost Effectiveness of Cochlear Implantation in Single-Sided Deafness.

OBJECTIVE: To analyze the cost effectiveness of cochlear implantation (CI) for the treatment of single-sided deafness (SSD). STUDY DESIGN: Cost-utility analysis in an adapted Markov model. SETTING: Adults with single-sided deafness in a high-income country. INTERVENTION: Unilateral CI was compared with no intervention. MAIN OUTCOME MEASURE: Incremental cost-effectiveness ratios were compared with different cost-effectiveness thresholds ($10,000 to $150,000) for different age, sex, and cost combinations. The calculations were based on the quality-adjusted life year (QALY), national life expectancy tables, and different cost settings. The health utility values for the QALY were either directly collected from published data, or, derived from published data using a regression model of multiple utility indices (regression estimate). RESULTS: The regression estimate showed an increase of the health utility value from 0.62 to 0.74 for SSD patients who underwent CI. CI for SSD was cost effective for women up to 64 years ($50,000 per-QALY threshold), 80 years ($100,000 per-QALY threshold), and 86 years ($150,000 per-QALY threshold). For men, these values were 58, 77, and 84, respectively. Changing the discount rate by up to 5% further increased the cutoff ages up to 5 years. A detailed cost and age sensitivity analysis is presented and allows testing for cost effectiveness in local settings worldwide. CONCLUSIONS: CI is a cost-effective option to treat patients with SSD.

Correlation between Speech Perception Outcomes after Cochlear Implantation and Postoperative Acoustic and Electric Hearing Thresholds.

The reliable prediction of cochlear implant (CI) speech perception outcomes is highly relevant and can facilitate the monitoring of postoperative hearing performance. To date, multiple audiometric, demographic, and surgical variables have shown some degree of correlation with CI speech perception outcomes. In the present study, postsurgical acoustic and electric hearing thresholds that are routinely assessed in clinical practice were compared to CI speech perception outcomes in order to reveal possible markers of postoperative cochlear health. A total of 237 CI recipients were included in this retrospective monocentric study. An analysis of the correlation of postoperative pure-tone averages (PTAs) and electric CI fitting thresholds (T-/C-levels) with speech perception scores for monosyllabic words in quiet was performed. Additionally, a correlation analysis was performed for postoperative acoustic thresholds in intracochlear electrocochleography (EcochG) and speech recognition scores in a smaller group (n = 14). The results show that neither postoperative acoustic hearing thresholds nor electric thresholds correlate with postoperative speech perception outcomes, and they do not serve as independent predictors of speech perception outcomes. By contrast, the postoperative intracochlear total EcochG response was significantly correlated with speech perception. Since the EcochG recordings were only performed in a small population, a large study is required to clarify the usefulness of this promising predictive parameter.

Electrode migration after cochlear implantation.

Objective: To investigate impedance change of cochlear implant (CI) electrodes from CochlearTM in patients with straight and precurved electrodes, and to determine if impedance change of the basal electrodes are indicative for cochlear electrode migration. Methods: Retrospective case series at an academic tertiary referral center. Five hundred sixty patients (414 precurved, 146 straight) received a CI from CochlearTM between January 2010 and August 2018. Electrode impedance measured intraoperatively and during follow-up has been assessed. In case of impedance change of the 3 most basal electrodes a computer tomography (CT) scan has been performed. Cochlear position of the electrode array has been determined and compared to the one day postoperative electrode position (plain radiography). Results: Changes in electrode impedance in the basal electrodes occurred in 2.1% ears (n = 12). CT scan was available in 9 patients and revealed a migration of the electrode array in 6 patients. Straight electrode types showed a significantly higher migration rate than precurved electrode types (4.1% vs 0%). Conclusions: Electrode impedance is a useful tool to investigate electrode array integrity as well as to raise suspicion of possible electrode migration. Patients implanted with a straight electrode from CochlearTM array might benefit from lead wire fixation.

Conductive Hearing Loss with Age-A Histologic and Audiometric Evaluation.

A retrospective analysis to quantify age-related changes of the incudo-malleolar joint (IMJ) and incudo-stapedial joint (ISJ), and to analyse changes in the air-bone gap (ABG) with age, was performed. Defined histologic parameters of 153 IMJ and 106 ISJ from subjects aged from birth to 70 years were correlated to age. Additionally, audiograms of 1760 ears of 974 other subjects aged 20 to 80 years were retrospectively analysed and the ABG was correlated to age. The joint space (age group from 0 to 10 compared to 61 to 70 years) became significantly wider with age (IMJ: from a mean of 44 µm to 100 µm, p < 0.001; ISJ: from a mean of 28 µm to 69 µm, p < 0.009. The thickness of cartilage of the incus decreased in the first 20 years of life (IMJ, from a mean of 88 µm to 65 µm, p < 0.01; ISJ: from a mean of 44 µm to 35 µm, p < 0.01). The ABGs of younger ears (20-40 years) was significantly larger at 500 Hz compared to older ears (60-80 years) by 2-4 dB, while it was significantly smaller by 3-5 dB at 4000 Hz (p < 0.0017). Interindividual variations in all age groups were large for both analyses. The increased joint spaces could potentially reduce the stiffness in the joints and explain the increase in ABG at 4000 Hz and the drop at 500 Hz. While the average change is small and of minimal clinical relevance, a larger increase of ABG with age is seen in some subjects.

Assessment of Surgical Complications With Respect to the Surgical Indication: Proposal for a Novel Index.

Introduction: The Clavien-Dindo classification is a broadly accepted surgical complications classification system, grading complications by the extent of therapy necessary to resolve them. A drawback of the method is that it does not consider why the patient was operated on primarily. Methods: We designed a novel index based on Clavien-Dindo but with respect to the surgical indication. We surveyed an international panel of otolaryngologists who filled out a questionnaire with 32 real case-inspired scenarios. Each case was graded for the surgical complication, surgical indication, and a subjective rating whether the complication was acceptable or not. Results: Seventy-seven otolaryngologists responded to the survey. Mean subjective rating and surgical complication grading for each scenario showed an inverse correlation (r 2 = 0.147, p = 0.044). When grading the surgical complication with respect to the surgical indication, the correlation with the subjective rating increased dramatically (r 2 = 0.307, p = 0.0022). Conclusion: We describe a novel index grading surgical complications with respect to the surgical indication. In our survey, most respondents judged a complication as acceptable or not according to its grade but kept in mind the surgical indication. This subjective judgment could be quantified with our novel index.

CRIM-negative infantile Pompe disease: 42-month treatment outcome.

Pompe disease is a rare lysosomal glycogen storage disorder characterized by deficiency of acid α-glucosidase enzyme (GAA) and caused by mutations in the GAA gene. Infantile-type Pompe disease is a multiorgan disorder presenting with cardiomyopathy, hypotonia, and muscular weakness, which is usually fatal. Enzyme replacement therapy (ERT) with recombinant human GAA (rhGAA) has recently been shown to be effective and subsequently yielded promising results in cross-reactive immunologic material (CRIM)-positive patients. CRIM-negative patients showed a limited response to ERT and died or were ventilator dependant. Over a period of 44 months, we monitored cognitive and motor development, behavior, auditory function, and brain imaging of a CRIM-negative infantile Pompe disease patient on rhGAA and monoclonal anti-immunoglobulin E (anti-IgE) antibody (omalizumab) treatment due to severe allergic reaction. Cardiorespiratory and skeletal muscle response was significant, with almost normal motor development. Cognitive development-in particular, speech and language-deviated increasingly from normal age-appropriate development and was markedly delayed at 44 months, unexplained by moderate sensorineural hearing impairment. Brain magnetic resonance imaging (MRI) at 18, 30, and 44 months of age revealed symmetrical signal alteration of the deep white matter. Titer values of IgG antibodies to rhGAA always remained <1:800. The potential role of omalizumab in immune modulation remains to be elucidated; however, this is the first report presenting a ventilator-free survival of a CRIM-negative patient beyond the age of 36 months. The central nervous system (CNS) findings are hypothesized to be part of a yet not fully described CNS phenotype in treated patients with longer survival.