Implantation and reimplantation: epidemiology, etiology and pathogenesis over the last 30 years.

INTRODUCTION: Due to the increasing number of cochlear implant (CI) recipients, growing indications, and the aging population, the reimplantation of CI recipients has become a focus of attention. The aim of this study is to examine the causes, timing, and postoperative speech understanding in a large cohort over the past 30 years. METHODS: A retrospective data analysis was conducted on over 4000 CI recipients and 214 reimplanted children and adults from 1993 to 2020. This involved collecting and comparing data on causes, manufacturer information, and demographic data. In addition, a comparison of speech understanding in Freiburg monosyllables and numbers before and after reimplantation was carried out. RESULTS: Children did not exhibit elevated rates of reimplantation. The overall reimplantation rate in the entire cohort was 5%. The CI overall survival rate after 10 years in the entire cohort was 95.2%. Device failure was the most common reason for reimplantation, with 48% occurring within the first 5 years after implantation. The second most common reason was medical complications, with the risk of reimplantation decreasing as more time passed since the initial implantation. There were no significant differences in Freiburg numbers and monosyllable comprehension before and after reimplantation, both in the overall cohort and in the subcohorts based on indications. Even a technical upgrade did not result in a significant improvement in speech understanding. DISCUSSION: There was no significant difference in the frequency of reimplantation based on patient age, especially when comparing children and adults. Device failure is by far the most common indication for reimplantation, with no significant difference in implant survival between manufacturers. Patients most often choose the same manufacturer for reimplantation. The likelihood of reimplantation decreases with increasing time since the initial implantation. The indication for reimplantation should be carefully considered, as on average, no improved speech understanding is achieved, regardless of the cause, even with a technical upgrade.

Insertion of a second electrode array-a rare complication of CI reimplantation.

Due to a technical defect or a medical indication, it may be necessary to explant a cochlear implant. This case report shows that there is the risk of encountering a nonremovable electrode array-as described here from the scala tympani-during cochlear reimplantation. In the present case, insertion of a second electrode array into the free and nonobstructed scala vestibuli was successful. Nonetheless, the indication for reimplantation must be carefully considered, especially in patients with tolerable limitations with little or no loss of speech understanding. Furthermore, surgery should not be performed solely because an implant upgrade is desired.

[Insertion of a second electrode array-a rare complication of CI reimplantation. German version]. / Insertion eines zweiten Elektrodenträgers ­ eine seltene Komplikation bei CI-Reimplantation.

Due to a technical defect or a medical indication, it may be necessary to explant a cochlear implant. This case report shows that there is the risk of encountering a nonremovable electrode array-as described here from the scala tympani-during cochlear reimplantation. In the present case, insertion of a second electrode array into the free and nonobstructed scala vestibuli was successful. Nonetheless, the indication for reimplantation must be carefully considered, especially in patients with tolerable limitations with little or no loss of speech understanding. Furthermore, surgery should not be performed solely because an implant upgrade is desired.

Evaluation of insertion quality of a slim perimodiolar electrode array.

OBJECTIVES: The influence of cochlear morphology and electrode array design on scalar position and dislocation rates is of great interest in CI surgery. The aim of this study is to evaluate scalar position and specific points of dislocation in relation to cochlear morphology in patients implanted with a new slim perimodiolar electrode array. MATERIALS AND METHODS: Patients were implanted using the slim modiolar electrode array (= SMA) (= 532/632 electrode array of Cochlear™). Postoperative imaging was performed via cone beam computed tomography (CBCT) and the scans were analyzed regarding cochlear morphology (distances A and B and cochlear height), scalar location of the electrode array, basal insertion depth and apical insertion angle. Furthermore, electrode array design and surgical protocols were evaluated. RESULTS: 81 ears implanted with the SMA were retrospectively included. We evaluated 3 electrode array tip fold over intraoperatively via X-ray imaging and performed revision during the same surgery. The CBCT scans showed 76 initial scala tympani (ST) insertions without dislocation. Two ears showed a dislocated array, one at 77° and the other at 163°. Three arrays were inserted into scala vestibuli (SV) via cochleostomy. These patients showed no signs of obliteration. Cochlear morphology showed no influence on angular insertion depth and scalar position. CONCLUSIONS: The SMA showed a very low rate of scalar dislocations due to its slim electrode array design (2.7%). We could find a learning curve regarding the handling and the risk of dislocation and tip fold over with this electrode array. The rate of intraoperative tip fold over detection via X-ray imaging was 3.7%. Therefore, we highly recommend X-ray imaging and transimpedance matrix measurements within the surgery protocol. Scala vestibuli insertions happened in patients with cochleostomy only. We could identify two specific points of dislocation depending on electrode array design.

Subsea permafrost organic carbon stocks are large and of dominantly low reactivity.

Subsea permafrost carbon pools below the Arctic shelf seas are a major unknown in the global carbon cycle. We combine a numerical model of sedimentation and permafrost evolution with simplified carbon turnover to estimate accumulation and microbial decomposition of organic matter on the pan-Arctic shelf over the past four glacial cycles. We find that Arctic shelf permafrost is a globally important long-term carbon sink storing 2822 (1518-4982) Pg OC, double the amount stored in lowland permafrost. Although currently thawing, prior microbial decomposition and organic matter aging limit decomposition rates to less than 48 Tg OC/yr (25-85) constraining emissions due to thaw and suggesting that the large permafrost shelf carbon pool is largely insensitive to thaw. We identify an urgent need to reduce uncertainty in rates of microbial decomposition of organic matter in cold and saline subaquatic environments. Large emissions of methane more likely derive from older and deeper sources than from organic matter in thawing permafrost.

Association of polymorphous light eruption with NOD-2 and TLR-5 gene polymorphisms.

BACKGROUND: Polymorphous light eruption (PLE) is a common, immunologically mediated, photosensitive skin disease. After ultraviolet-B (UV-B) irradiation, patients with PLE show reduced Langerhans cell (LC) depletion in the epidermis, which results in a non-suppressive microenvironment in the skin. Interestingly, severe acute graft-versus-host disease (aGvHD) occurred in stem cell transplanted patients that showed no or incomplete depletion of LCs after UVB irradiation. Genetic variation in nucleotide-binding oligomerization domain 2 (NOD-2) and toll-like receptor 5 (TLR-5) genes also confers susceptibility to aGvHD. OBJECTIVES: We hypothesized that PLE is associated with genetic variation in the NOD-2 and TLR-5 genes. METHODS: We investigated single-nucleotid polymorphisms (SNPs) of NOD-2 (R702W, G908R, 3020Cins) and TLR-5 (A592S, P616L, N392STOP) in skin biopsies of patients with PLE (n = 143) and in healthy controls (n = 104) using restriction fragment length polymorphism analysis. RESULTS: The frequency of NOD-2 alleles with the SNP R702W was significantly higher in PLE than in controls (31.8% vs. 6.3%; P < 0.0001), and homozygous carriers of this mutation were more common in PLE (27.9% vs. 0%; P < 0.0001). For SNP 3020Cins, the allele frequency (7.3% vs. 0.7%; P = 0.0025) and the number of heterozygotes (14.7% vs. 1.3%; P = 0.0019) were higher in PLE. The frequency of alleles with the N392STOP SNP of the TLR5 gene, which is associated with a truncated, non-functional receptor, was significantly higher in PLE (21% vs. 5%; 7% vs. 1% homozygotes, 28% vs. 8% heterozygotes; P < 0.0001). The other SNPs did not differ significantly. CONCLUSIONS: This study yielded a high frequency of functional SNPs in the NOD-2 and TLR-5 genes in PLE. The same SNPs are associated with aGvHD and there are similarities in the reaction of LCs after UVB irradiation between aGvHD and PLE. This leads to the hypothesis that patients with PLE may be more susceptible to developing GvHD after stem cell transplantation, an assumption that needs to be investigated further.

Scalar position, dislocation analysis and outcome in CI reimplantation due to device failure.

OBJECTIVE: Due to increasing indication for cochlear implantation (CI), reimplantation and technical upgrades their consequences are a special focus in CI surgery research. The aim of this study is to examine the indication and influences on both morphological position of the electrode array and audiological outcome following reimplantation. DESIGN: This is a retrospective analysis of adult CI patients reimplanted between 2004 and 2019. We evaluated the scalar position in pre- and postoperative cone beam computed tomography (CBCT) after CI and reimplantation and examined the indication for and the audiological outcome following reimplantation. RESULTS: The reimplanted patients showed stable and comparable audiological results for monosyllables and numbers for best fitted situation before and following reimplantation. Technical upgrades did not result in a significant improvement of speech perception. CBCT scans of reimplanted ears did not show significant increased rates of scalar dislocation or partial insertion. CONCLUSION: Even with a technical upgrade, reimplantation does not improve speech perception outcome in CI patients. Therefore, the indication to reimplant should be approved critically. Reimplantation does not lead to a significantly increased risk for partial insertion, scalar dislocation or diminished electrode array insertion angle.

Hearing outcome after tympanoplasty type III.

PURPOSE: We assessed overall hearing outcome after tympanoplasty type III in chronically infected ears with cholesteatoma (CH) and without cholesteatoma: otitis media chronica mesotympanalis, tympanosclerosis, and adhesive process (COM_T_AP). METHODS: 303 surgeries were evaluated: 229 CH-group and 74 COM_T_AP-group. Air-bone gaps (PTA-ABG) with pure-tone averages (PTA-4) at four frequencies (0.5, 1, 2 and 4 kHz) were compared preoperatively, early postoperatively (< 40 days) and late postoperatively (40-400 days). Hearing outcome was compared in various types of middle-ear reconstruction and in smokers and non-smokers. Correlations between hearing outcome and predictive staging indices were evaluated: Middle Ear Risk-Index (MER-I) and Ossiculoplasty Outcome Parameter Staging-Index (OOPS-I). RESULTS: Mean PTA-ABG in the CH-group increased from 20.9 ± 11.3 dB to 22.3 ± 10.4 dB early postoperatively and decreased significantly to 19.2 ± 10.1 dB late postoperatively. Mean PTA-ABG in the COM_T_AP-group decreased significantly from 27.3 ± 10.9 dB to 20.6 ± 10.9 dB early postoperatively and decreased to 20.0 ± 12.2 dB late postoperatively. No significant difference was seen between PTA-ABG-closures of partial or total ossicular replacement prosthesis (PORP/TORP) and cartilage ossiculoplasty in the CH-group. Patients receiving TORP showed a significantly higher preoperative PTA-ABG. All reconstruction types exhibited postoperative PTA-ABG around 20 dB. In the COM_T_AP-group, smokers had a significantly higher mean PTA-ABG early postoperatively; this equalized with that of non-smokers late postoperatively. PTA-ABG-closures and MER-I or OOPS-I were not significantly correlated. CONCLUSION: Tympanoplasty type III maintains hearing in patients with cholesteatoma and significantly improves hearing in chronically inflamed ears without cholesteatoma. All investigated ossicular replacement prostheses are equally beneficial. Healing postoperatively takes longer in smokers, but they eventually catch up with non-smokers.

Active transcutaneous bone-anchored hearing implant: how I do it.

BACKGROUND: The Cochlear™ Osia® System leaves a retroauricular bump that can cause discomfort and poor aesthetic outcome. METHOD: To reduce the retroauricular bump, we introduced an implant well in the bone behind the ear for the transducer. We used cutting and diamond drills to create the implant well with an average depth of 4-5 mm. The surgical time including the implant well (40 min) was within the range of reported average surgical time (52 min). CONCLUSION: Introduction of an implant well resulted in a better aesthetic outcome and improved patients' comfort. The reduced distance between BI300 and ear canal might improve audiological outcome.

Deafness after COVID-19?

This article presents a case of sudden bilateral deafness in the context of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection and resultant coronavirus disease 2019 (COVID-19). After treatment in the intensive care unit for acute respiratory distress syndrome and acute kidney failure, hearing ability had drastically changed. While hearing had been subjectively normal before the infection, deafness was now measured on the left and profound hearing loss on the right ear. The patient was treated with cochlea implants on the left and a hearing aid in the right ear. The hearing loss is most likely a complication of COVID-19.

[Deafness after COVID-19? German version]. / Ertaubung nach COVID-19?

This article presents a case of sudden bilateral deafness in the context of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection and resultant coronavirus disease 2019 (COVID-19). After treatment in the intensive care unit for acute respiratory distress syndrome and acute kidney failure, hearing ability had drastically changed. While hearing had been subjectively normal before the infection, deafness was now measured on the left and profound hearing loss on the right ear. The patient was treated with cochlea implants on the left and a hearing aid in the right ear. The hearing loss is most likely a complication of COVID-19.

Navigated, endoscopically controlled, transtympanic resection of an infracochlear cholesteastoma recurrence.

An infracochlear cholesteatoma of the petrous apex with direct contact to the internal carotid artery (ICA) is rare. Due to the risk of cochlear injury with consecutive deafness or injury of the ICA, precise preoperative planning of the approach and strategy is recommended, as well as thorough preoperative counseling of the patient for their informed consent. This case report presents navigated endoscopically controlled transtympanic resection of such a cholesteatoma recurrence. Hearing capacity was not impaired and the patient shows no signs of recurrence.

[Navigated endoscopically controlled transtympanic resection of an infracochlear cholesteatoma recurrence. German version]. / Navigierte endoskopisch-kontrollierte transtympanale Resektion eines infracochleären Cholesteatomrezidivs.

An infracochlear cholesteatoma of the petrous apex with direct contact to the internal carotid artery (ICA) is rare. Due to the risk of cochlear injury with consecutive deafness or injury of the ICA, precise preoperative planning of the approach and strategy is recommended, as well as thorough preoperative counseling of the patient for their informed consent. This case report presents navigated endoscopically controlled transtympanic resection of such a cholesteatoma recurrence. Hearing capacity was not impaired and the patient shows no signs of recurrence.

Speech Recognition in Noise in Single-Sided Deaf Cochlear Implant Children on Using Adaptive Digital Microphone Technology.

BACKGROUND: Previous research demonstrated benefits of adaptive digital microphone technologies (ADMTs) in adults with single-sided deafness (SSD) having a cochlear implant (CI). Children with SSD are especially affected by background noise because of their noise exposure in kindergarten and school. PURPOSE: This article aims to evaluate possible effects of ADMT on speech recognition in background noise in children with SSD who use a CI. STUDY SAMPLE: Ten children between 5 and 11 years of age were included. DATA COLLECTION AND ANALYSIS: Speech recognition in noise was assessed for one frontal distant and two lateral speakers. The speech stimulus was presented at a speech level of 65 dB(A) and noise at a level of 55 dB(A). For the presentation condition with one frontal speaker, four listening conditions were assessed: (1) normal-hearing (NH) ear and CI turned off; (2) NH ear and CI; (3) NH ear and CI with ADMT; and (4) NH ear with ADMT and CI. Listening conditions (2) to (4) were also tested for each lateral speaker. The frontal speaker was positioned directly in front of the participant, whereas the lateral speakers were positioned at angles of 90 degrees and -90 degrees to the participant's head. RESULTS: Children with SSD who use a CI significantly benefit from the application of ADMT in speech recognition in noise for frontal distant and for lateral speakers. Speech recognition improved significantly with ADMT at the CI and the NH ears. CONCLUSION: Application of ADMT significantly improves speech recognition in noise in children with SSD who use a CI and can therefore be highly recommended. The decision of whether to apply ADMT at the CI NH ear or bilaterally should be made for each child individually.

Relationships among gastrointestinal symptoms, sleep problems, challenging behaviour, comorbid psychopathology and autism spectrum disorder symptoms in children and adolescents with 15q duplication syndrome.

BACKGROUND: Comorbidity is the presence of at least two disorders in one person at one time. This study examined the frequency of gastrointestinal (GI) symptoms, sleep problems, comorbid psychopathology, challenging behaviour and autism spectrum disorder (ASD) symptoms in children and adolescents with duplication 15q syndrome (Dup15q), aged 3-17 years. This study also examined whether challenging behaviour in Dup15q is predicted by age, gender, presence of an intellectual disability, sleep problems, GI symptoms and comorbid psychopathology. METHOD: Parental measures were completed by 101 parents of children and adolescents with Dup15q. Questionnaires were composed of the Children's Sleep Habits Questionnaire, Behavior Problems Inventory - Short Form, GI Symptom Inventory, Social Communication Questionnaire and the Child Behavior Checklist. RESULTS: Sleep problems (94%), GI symptoms (87%) and challenging behaviour (100%) were common comorbidities represented in the sample in this study. Significant relationships were found between challenging behaviour and the presence of co-occurring sleep problems, GI symptoms, comorbid psychopathology and ASD symptoms. Further analysis revealed that these comorbidities also predicted challenging behaviour. CONCLUSION: This research demonstrated the importance of studying the relationships between GI symptoms, sleep problems, comorbid psychopathology, ASD symptoms and challenging behaviour in Dup15q and how these conditions can shape the Dup15q phenotype.

Quality of cochlear implant rehabilitation under COVID-19 conditions.

BACKGROUND: The rehabilitation process following cochlear implant (CI) surgery is carried out in a multimodal therapy according to German national guidelines and includes technical and medical aftercare. In times of the corona pandemic surgery and rehabilitation appointments were cancelled or delayed leading to a more difficult access to auditory rehabilitation. Newly implemented hygiene modalities due to the SARS-CoV­2 pandemic have changed medical aftercare and the rehabilitation process. The aim of this study was to evaluate the quality of rehabilitation under corona conditions. MATERIAL AND METHODS: An anonymous survey of adult cochlear implant patients was carried out by a non-standardized questionnaire. Demographics were analyzed and the quality of medical aftercare, speech therapy, technical aftercare, psychological support and the hygiene modalities were compared to previous rehabilitation stays. RESULTS: In total 109 patients completed the questionnaire. The quality of rehabilitation and individual therapy were rated as qualitatively similar or improved. The threat of the pandemic and fear of corona were rated unexpectedly high with 68% and 50%, respectively. The hygiene measures during the rehabilitation stay eased subjective fears at the same time. The majority of patients were annoyed by wearing face masks but visors, protection shields and social distancing were more tolerated. CONCLUSION: The implementation of the new hygiene modalities within the therapeutic rehabilitation setting was well-accepted by patients allowing access to auditory rehabilitation. A successful rehabilitation should ensure a fear-free environment by adhering to the necessary hygiene modalities.

Radiological evaluation of a new straight electrode array compared to its precursors.

OBJECTIVE: The aim of this study is to examine electrode array coverage, scalar position and dislocation rate in straight electrode arrays with special focus on a new electrode array with 26 mm in lengths. STUDY DESIGN: Retrospective study. SETTING: Tertiary academic center. PATIENTS: 201 ears implanted between 2013 and 2019. MAIN OUTCOME MEASURES: We conducted a comparative analysis of patients implanted with lateral wall electrode arrays of different lengths (F24 = MED-EL Flex24, F26 = MED-EL Flex26, F28 = MED-EL Flex28 and F31.5 = MED-EL FlexSoft). Cone beam computed tomography was used to determine electrode array position (scala tympani (ST) versus scala vestibuli (SV), intracochlear dislocation, position of dislocation and insertion angle). RESULTS: Study groups show no significant differences regarding cochlear size which excludes influences by cochlear morphology. As expected, the F24 showed significant shorter insertion angles compared to the longer electrode arrays. The F26 electrode array showed no signs of dislocation or SV insertion. The electrode array with the highest rate of ST dislocations was the F31.5 (26.3%). The electrode array with the highest rates of SV insertions was the F28 (5.75%). Most of the included electrode arrays dislocate between 320° and 360° (mean: 346.4°; range from 166° to 502°). CONCLUSION: The shorter F24 and the new straight electrode array F26 show less or no signs of scalar dislocation, neither for round window nor for cochleostomy insertion than the longer F28 and the F31.5 array. As expected, the cochlear coverage is increasing with length of the electrode array itself but with growing risk for scalar dislocation and with the highest rates of dislocation for the longest electrode array F31.5. Position of intracochlear dislocation is in the apical cochlear part in the included lateral wall electrode arrays.

[Quality of cochlear implant rehabilitation under COVID-19 conditions. German version]. / Qualität der Cochleaimplantat-Rehabilitation unter COVID-19-Bedingungen.

BACKGROUND: The rehabilitation process following cochlear implant (CI) surgery is carried out in a multimodal therapy according to German national guidelines and includes technical and medical aftercare. In times of the corona pandemic surgery and rehabilitation appointments were cancelled or delayed leading to a more difficult access to auditory rehabilitation. Newly implemented hygiene modalities due to the SARS-CoV­2 pandemic have changed medical aftercare and the rehabilitation process. The aim of this study was to evaluate the quality of rehabilitation under corona conditions. MATERIAL AND METHODS: An anonymous survey of adult cochlear implant patients was carried out by a non-standardized questionnaire. Demographics were analyzed and the quality of medical aftercare, speech therapy, technical aftercare, psychological support and the hygiene modalities were compared to previous rehabilitation stays. RESULTS: In total 109 patients completed the questionnaire. The quality of rehabilitation and individual therapy were rated as qualitatively similar or improved. The threat of the pandemic and fear of corona were rated unexpectedly high with 68% and 50%, respectively. The hygiene measures during the rehabilitation stay eased subjective fears at the same time. The majority of patients were annoyed by wearing face masks but visors, protection shields and social distancing were more tolerated. CONCLUSION: The implementation of the new hygiene modalities within the therapeutic rehabilitation setting was well-accepted by patients allowing access to auditory rehabilitation. A successful rehabilitation should ensure a fear-free environment by adhering to the necessary hygiene modalities.

Widespread energy limitation to life in global subseafloor sediments.

Microbial cells buried in subseafloor sediments comprise a substantial portion of Earth's biosphere and control global biogeochemical cycles; however, the rate at which they use energy (i.e., power) is virtually unknown. Here, we quantify organic matter degradation and calculate the power utilization of microbial cells throughout Earth's Quaternary-age subseafloor sediments. Aerobic respiration, sulfate reduction, and methanogenesis mediate 6.9, 64.5, and 28.6% of global subseafloor organic matter degradation, respectively. The total power utilization of the subseafloor sediment biosphere is 37.3 gigawatts, less than 0.1% of the power produced in the marine photic zone. Aerobic heterotrophs use the largest share of global power (54.5%) with a median power utilization of 2.23 × 10-18 watts per cell, while sulfate reducers and methanogens use 1.08 × 10-19 and 1.50 × 10-20 watts per cell, respectively. Most subseafloor cells subsist at energy fluxes lower than have previously been shown to support life, calling into question the power limit to life.

Electrophysiological detection of electrode fold-over in perimodiolar cochlear implant electrode arrays: a multi-center study case series.

PURPOSE: It is important for the surgeon to determine the position of the CI electrode array during and after its placement within the cochlea. Most preferably, this should be within the scala tympani to obtain the best audiological outcome. Thus, misplacement into the scala vestibuli or tip fold-over should be prevented. Since there are different ways to ensure proper positioning of the electrode array within the scala tympani (e.g., intraoperative radiography, electrophysiological recordings), our study was aimed at detecting intraoperative electrophysiologic characteristics to better understand the mechanisms of those electrode tip fold-overs. MATERIAL AND METHODS: In a multi-centric, retrospective case-control series, patients with a postoperatively by radiography detected tip fold-over in perimodiolar electrodes were included. The point of fold-over (i.e., the electrode position) was determined and the intraoperative Auto-NRT recordings were analysed and evaluated. RESULTS: Four patients were found to have an electrode tip fold-over (out of 85 implantees). Significant changes of the Auto-NRT recordings were not detected. All tip fold-overs occurred in the most apical part of the electrodes. DISCUSSION: Cochlear implantation for hearing impaired patients plays a decisive role in modern auditory rehabilitation. Perimodiolar electrode arrays may fold over during the insertion and, hence, could have a negative impact on audiological outcome. Characteristic electrophysiologic changes to possibly predict this were not found in our series.