The effect of piston diameter in primary stapes surgery on surgical success.

PURPOSE: To evaluate the effect of piston diameter in patients undergoing primary stapes surgery on audiometric results and postoperative complications. METHODS: A retrospective single-center cohort study was performed. Adult patients who underwent primary stapes surgery between January 2013 and April 2022 and received a 0.4-mm-diameter piston or a 0.6-mm-diameter piston were included. The primary and secondary outcomes were pre- and postoperative pure-tone audiometry, pre- and postoperative speech audiometry, postoperative complications, intraoperative anatomical difficulties, and the need for revision stapes surgery. The pure-tone audiometry included air conduction, bone conduction, and air-bone gap averaged over 0.5, 1, 2 and 3 kHz. RESULTS: In total, 280 otosclerosis patients who underwent 321 primary stapes surgeries were included. The audiometric outcomes were significantly better in the 0.6 mm group compared to the 0.4 mm group in terms of gain in air conduction (median = 24 and 20 dB, respectively), postoperative air-bone gap (median = 7.5 and 9.4 dB, respectively), gain in air-bone gap (median = 20.0 and 18.1 dB, respectively), air-bone gap closure to 10 dB or less (75% and 59%, respectively) and 100% speech reception (median = 75 and 80 dB, respectively). We found no statistically significant difference in postoperative dizziness, postoperative complications and the need for revision stapes surgery between the 0.4 and 0.6 mm group. The incidence of anatomical difficulties was higher in the 0.4 mm group. CONCLUSION: The use of a 0.6-mm-diameter piston during stapes surgery seems to provide better audiometric results compared to a 0.4-mm-diameter piston, and should be the preferred piston size in otosclerosis surgery. We found no statistically significant difference in postoperative complications between the 0.4- and 0.6-mm-diameter piston. Based on the results, we recommend always using a 0.6-mm-diameter piston during primary stapes surgery unless anatomical difficulties do not allow it.

The cost evaluation of day-case compared to inpatient cochlear implantation in adults: subanalysis of a randomized controlled trial.

OBJECTIVE: To investigate the assumption that day-case cochlear implantation is associated with lower costs, compared to inpatient cochlear implantation, while maintaining equal quality of life (QoL) and hearing outcomes, for the Dutch healthcare setting. STUDY DESIGN: A single-center, non-blinded, randomized controlled trial in a tertiary referral center. METHODS: Thirty adult patients with post-lingual bilateral sensorineural hearing loss eligible for unilateral cochlear implantation surgery were randomly assigned to either the day-case or inpatient treatment group (i.e., one night admission). We performed an intention-to-treat evaluation of the difference of the total health care-related costs, hospital and out of hospital costs, between day-case and inpatient cochlear implantation, from a hospital and patient perspective over the course of one year. Audiometric outcomes, assessed using CVC scores, and QoL, assessed using the EQ-5D and HUI3 questionnaires, were taken into account. RESULTS: There were two drop-outs. The total health care-related costs were €41,828 in the inpatient group (n = 14) and €42,710 in the day-case group (n = 14). The mean postoperative hospital stay was 1.2 days (mean costs of €1,069) in the inpatient group and 0.7 days (mean costs of €701) for the day-case group. There were no statistically significant differences in postoperative hospital and out of hospital costs. The QoL at 2 months and 1 year postoperative, measured by the EQ-5D index value and HUI3 showed no statistically significant difference. The EQ-5D VAS score measured at 1 year postoperatively was statistically significantly higher in the inpatient group (84/100) than in the day-case group (65/100). There were no differences in postoperative complications, objective hearing outcomes, and number of postoperative hospital and out of hospital visits. CONCLUSION: A day-case approach to cochlear implant surgery does not result in a statistically significant reduction of health care-related costs compared to an inpatient approach and does not affect the surgical outcome (complications and objective hearing measurements), QoL, and postoperative course (number of postoperative hospital and out of hospital visits).

Quality of life, hearing results, patient satisfaction and postoperative complications of day-case versus inpatient unilateral cochlear implantation in adults: a randomized controlled, equivalence trial.

OBJECTIVE: To investigate the hypothesis that day-case cochlear implantation is associated with equal quality of life, hearing benefits and complications rates, compared to inpatient cochlear implantation. STUDY DESIGN: A single-center, non-blinded, randomized controlled, equivalence trial in a tertiary referral center. METHODS: Thirty adult patients with post-lingual bilateral sensorineural hearing loss eligible for unilateral cochlear implantation surgery were randomly assigned to either the day-case or inpatient treatment group. The effect on general quality of life, patient satisfaction, (subjective) hearing improvement, postoperative complications and causes of crossover and/or readmission were assessed using questionnaires, auditory evaluations and patients' charts over a follow-up period of 1 year. RESULTS: Overall quality of life measured by the HUI3 was equal between the day-case (n = 14) and inpatient group (n = 14). The overall patients' satisfaction showed a slight favor towards an inpatient approach. There was no significant difference in the subjective and objective hearing improvement between both treatment groups. During the 1-year follow-up period no major complications occurred. Minor complications occurred intraoperatively in three day-case patients resulting in three out of nine admissions of day-case patients. Other causes of admission of day-case patients were nausea and vomiting (n = 1), drowsiness (n = 1), late scheduled surgery (n = 2), social reasons (n = 1), or due to an unclear reason (n = 1). No patients required readmission. CONCLUSION: We found equal outcomes of QoL, patient satisfaction, objective, and subjective hearing outcomes between day-case and inpatient unilateral cochlear implantation. Nine out of 14 day-case patients were admitted for at least one night postoperatively (crossover). No major complications occurred in both groups. A day-case approach seems feasible when using specific patient selection, surgical planning and the preoperative provision of patient information into account. Besides this, the familiarity with a day-case approach of both patient and the surgical team can increase the feasibility of day-case surgery.

The Diagnostic Value of Multifrequency Tympanometry in Patients with Ménière's Disease: A Prospective Analysis.

INTRODUCTION: Diagnosing Ménière's disease (MD) by its characteristics such as episodes of vertigo, fluctuating hearing loss, and tinnitus with aural fullness remains challenging. Available tests evaluating the presence of endolymphatic hydrops (EH) are often expensive or time assuming. An in-office quick and simple non-invasive diagnostic test is multifrequency tympanometry (MFT). It can measure conductance at 2 kHz probe tones, which was demonstrated to reflect variations in cochlear pressure. Previous studies investigating MFT as a diagnostic test for MD showed conflicting outcomes possibly biased by their retrospective design. METHODS: We prospectively collected MFT results (Y width) in patients with dizziness and compared MFT test results in affected (group 1) and unaffected (group 2) ears of 37 MD subjects and in control ears of 33 non-MD subjects (group 3). RESULTS: The mean value of the Y width in affected ears was 315.6 ± 70.2 daPa compared to 292.3 ± 98.6 daPa in unaffected ears in MD subjects and 259.4. ± 60.6 daPa in the non-MD group. A positive test result (i.e., a Y width of 235 daPa or more) was found in 35 ears in the MD group, 21 times involving the affected ear and 14 times involving the unaffected ear, compared to 16 in the non-MD group. No significant differences between the three groups could be demonstrated (p > 0.05). We found a sensitivity of 58.3% and specificity of 66.3% for detecting EH in an affected ear in MD subjects. CONCLUSION: There is a trend towards increased conductance tympanometry in affected ears. However, we noticed a high false positive rate of MFT and do not support standardized use of MFT as an additional diagnostic tool for detecting EH in MD patients. A negative test result on the contrary is unlikely related to EH.

Labyrinthine fistulas: Surgical outcomes and an additional diagnostic strategy.

PURPOSE: To evaluate perioperative findings and audiological and vestibular outcomes in patients operated for cholesteatoma with labyrinthine fistulas. Also to assess radiological fistula size. MATERIALS AND METHODS: Patients who underwent surgery for a labyrinthine fistula caused by a cholesteatoma between 2015 and 2020 in a tertiary referral center were retrospectively investigated. Fistula size was determined on preoperative CT scan. Bone and air conduction pure tone average thresholds were obtained pre- and postoperatively. Clinical outcomes, such as vertigo and otorrea were also evaluated. Main purpose was to determine whether there is a correlation between fistula size and postoperative hearing. Furthermore, perioperative findings and vestibular outcomes are evaluated. RESULTS: 21 patients (22 cases) with a labyrinthine fistula were included. There was no significant change after surgery in bone conduction pure tone average (preoperatively 27.6 dB ± 26.7; postoperatively 30.3 dB ± 34.3; p = 0.628) or air conduction pure tone average (preoperatively 58.7 dB ± 24.3; postoperatively 60.2 dB ± 28.3; p = 0.816). Fistula size was not correlated to postoperative hearing outcome. There were two patients with membranous labyrinth invasion: one patient was deaf preoperatively, the other acquired total sensorineural hearing loss after surgery. CONCLUSIONS: Sensorineural hearing loss after cholesteatoma surgery with labyrinthine fistula is rare. Fistula size and postoperative hearing loss are not correlated, however, membranous labyrinthine invasion seems to be related to poor postoperative hearing outcomes. Therefore, additional preoperative radiological work up, by MRI scan, in selected cases is advocated to guide the surgeon to optimize preoperative counselling.

Radiological and surgical aspects of round window visibility during cochlear implantation: a retrospective analysis.

PURPOSE: The round window approach has become the most preferred option for cochlear implant (CI) insertion, however, sometimes it may not be possible due to the (in)visibility of the round window membrane (RWM). We addressed the prevalence, consequences and indicators of difficult detection of the RWM in cochlear implant surgery. METHODS: This study retrospectively analysed the operative reports and preoperative high resolution axial-computed tomography (CT) scans of a consecutive cohort of patients who underwent a CI insertion. The main outcomes were surgical outcomes of the RW approach, and assessment of radiological markers. RESULTS: The operative reports showed that RWM insertion was feasible in 151 out of 153 patients. In 18% of the patients the RWM was difficult to visualize. All these patients had at least one intraoperative event. The chorda tympani nerve (CTN) or posterior canal wall was affected in 8% of the 153 patients and the fallopian canal in 6%. These patients had a facial-chorda tympani nerve distance on the CT scan that was considerably smaller than normal patients (1.5 mm vs 2.3 mm). In addition, a prediction line towards the anterolateral side of the RWM was found to be more prevalent in these patients' CT scans (sensitivity 81%, specificity 63%). CONCLUSION: The RW approach is feasible in almost all patients undergoing CI surgery. Difficult visualisation of the RWM seems to lead to at least one intraoperative event. Radiological measures showed that these patients had a smaller facial recess and a more anteriorly placed facial nerve, which can be used to better plan a safe insertion approach.

Management of tympanic membrane retractions: a systematic review.

IMPORTANCE: Tympanic membrane retraction (TMR) is a relatively common otological finding. However, no consensus on its management exists. We are looking especially for a treatment strategy in the military population who are unable to attend frequent follow-up visits, and who experience relatively more barotrauma at great heights and depths and easily suffer from otitis externa from less hygienic circumstances. OBJECTIVE: To assess and summarize the available evidence for the effectiveness of surgical interventions and watchful waiting policy in patients with a tympanic membrane retraction. EVIDENCE REVIEW: The protocol for this systematic review was published at Prospero (207859). PubMed, Embase, and the Cochrane Database of Systematic Reviews were systematically searched from inception up to September 2020 for published and unpublished studies. We included randomized trials and observational studies that investigated surgical interventions (tympanoplasty, ventilation tube insertion) and wait-and-see policy. The primary outcomes of this study were clinical remission of the tympanic membrane retraction, tympanic membrane perforations and cholesteatoma development. FINDINGS: In total, 27 studies were included, consisting of 1566 patients with TMRs. We included data from 2 randomized controlled trials (76 patients) and 25 observational studies (1490 patients). Seven studies (329 patients) investigated excision of the TMR with and without ventilation tube placement, 3 studies (207 patients) investigated the wait-and-see policy and 17 studies (1030 patients) investigated tympanoplasty for the treatment of TMRs. CONCLUSIONS AND RELEVANCE: This study provides all the studies that have been published on the surgical management and wait-and-policy for tympanic membrane retractions. No high level of evidence comparative studies has been performed. The evidence for the management of tympanic membrane retractions is heterogenous and depends on many factors such as the patient population, location and severity of the TMR and presence of other ear pathologies (e.g., perforation, risk of cholesteatoma and serous otitis media).

Postoperative headache after surgical treatment of cerebellopontine angle tumors: a systematic review.

PURPOSE: Postoperative headache (POH) is a complication that occurs after surgical resection of cerebellopontine angle (CPA) tumors. The two most common surgical approaches are the translabyrinthine (TL), and retrosigmoid (RS) approach. The objective of this systematic review was to investigate whether POH occurs more frequently after RS compared to TL approaches. METHODS: A systematic search was conducted in Cochrane, Pubmed and Embase. Studies were included if POH after CPA tumor removal was reported and both surgical approaches were compared. The methodological quality of the studies was assessed using the Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool. RESULTS: In total, 3,942 unique articles were screened by title and abstract. After the initial screening process 63 articles were screened for relevance to the inquiry, of which seven studies were included. Three studies found no significant difference between both surgical approaches (p = 0.871, p = 0.120, p = 0.592). Three other studies found a lower rate of POH in the TL group compared to the RS group (p = 0.019, p < 0.001, p < 0.001). Another study showed a significantly lower POH rate in the TL group after one and six months (p = 0.006), but not after 1 year (p = 0.6). CONCLUSION: The results of this systematic review show some evidence of a lower rate of POH in favor of the TL approach versus the RS approach for CPA tumor resection. Prospective research studies are needed to further investigate this finding.

The effectiveness of hyperbaric oxygen in patients with idiopathic sudden sensorineural hearing loss: a systematic review.

OBJECTIVE: To evaluate the effectiveness of hyperbaric oxygen in the treatment of patients with idiopathic sudden sensorineural hearing loss (ISSHL). DATA SOURCES: An Embase, MEDLINE and Cochrane search were utilised to identify various clinical trials on the treatment of ISSHL. Studies that were published between 2002 and 2018 and written in the English, Dutch or German language were included. Search terms included synonyms for idiopathic sudden hearing loss. DATA SYNTHESIS: A total of 16 articles were identified regarding hyperbaric oxygen therapy. All patients were evaluated with pure-tone audiometry. A major part of the cases presented with unilateral hearing loss(bilateral hearing loss less than 5%). In several studies, the average of the mean hearing gain at five contiguous frequencies was significantly higher in the hyperbaric oxygen (HBO) therapy and systemic steroid (SS) group in patients with severe or profound hearing impairment. They recorded a significant treatment effect (p = 0.005) of HBO + SS therapy on patients with an initial hearing loss of ≥ 81 dB. CONCLUSIONS: On the whole group of ISSHL patients, no significant difference was demonstrated between the intervention and control group. However, in severe or profound hearing-impaired ISSHL patients, significant benefit was observed in the intervention group. These results likely indicate that adding HBO to steroid therapies might be of benefit in cases of severe and profound hearing impairment.

Towards Clinical Application of Neurotrophic Factors to the Auditory Nerve; Assessment of Safety and Efficacy by a Systematic Review of Neurotrophic Treatments in Humans.

Animal studies have evidenced protection of the auditory nerve by exogenous neurotrophic factors. In order to assess clinical applicability of neurotrophic treatment of the auditory nerve, the safety and efficacy of neurotrophic therapies in various human disorders were systematically reviewed. Outcomes of our literature search included disorder, neurotrophic factor, administration route, therapeutic outcome, and adverse event. From 2103 articles retrieved, 20 randomized controlled trials including 3974 patients were selected. Amyotrophic lateral sclerosis (53%) was the most frequently reported indication for neurotrophic therapy followed by diabetic polyneuropathy (28%). Ciliary neurotrophic factor (50%), nerve growth factor (24%) and insulin-like growth factor (21%) were most often used. Injection site reaction was a frequently occurring adverse event (61%) followed by asthenia (24%) and gastrointestinal disturbances (20%). Eighteen out of 20 trials deemed neurotrophic therapy to be safe, and six out of 17 studies concluded the neurotrophic therapy to be effective. Positive outcomes were generally small or contradicted by other studies. Most non-neurodegenerative diseases treated by targeted deliveries of neurotrophic factors were considered safe and effective. Hence, since local delivery to the cochlea is feasible, translation from animal studies to human trials in treating auditory nerve degeneration seems promising.

Cochlear implant positioning: development and validation of an automatic method using computed tomography image analysis.

The aim of this study was to preoperatively asses the feasibility of drilling a bony recess for the fixation of a cochlear implant in the temporal bone. Even though complications are rare with cochlear implantations, drilling at the site of implantation have resulted in hematoma or cerebrospinal fluid leakage. Mainly in cases with a reduced temporal bone thickness, the risk for complications has increased, such as in paediatric patients. Methods: An in-house designed semi-automatic algorithm was developed to analyse a 3D model of the skull. The feasibility of drilling the recess was determined by a gradient descent method to search for the thickest part of the temporal bone. Feasibility was determined by the residual bone thickness which was calculated after a simulated drilling of the recess at the thickest position. An initial validation of the algorithm was performed by measuring the accuracy of the algorithm on five 3D models with known thickest locations for the recess. The accuracy was determined by a part comparison between the known position and algorithm provided position. Results: In four of the five validation models a standard deviation for accuracy below the predetermined cut-off value of 4.2 mm was achieved between the actual thickest position and the position determined by the algorithm. Furthermore, the residual thickness calculated by the algorithm showed a high agreement (max. 0.02 mm difference) with the actual thickness. Conclusion: With the developed algorithm, a semi-automatic method was created to analyse the temporal bone thickness within a specified region of interest on the skull. Thereby, providing indications for surgical feasibility, potential risks for anatomical structures and impact on procedure time of cochlear implantation. This method could be a valuable research tool to objectively assess feasibility of drilling a recess in patients with thin temporal bones preoperatively.

Canal-wall up cholesteatoma surgery with mastoid obliteration leads to lower rates of disease recurrence without affecting hearing outcomes.

Objectives: The primary objective was to determine whether obliteration of the epitympanic area and mastoid cavity during canal wall up (CWU) cholesteatoma surgery reduces the rate of recurrent and residual cholesteatoma compared to not obliterating the same area. The secondary objective was to compare postoperative hearing outcomes between both techniques. Methods: A retrospective cohort study was conducted in a tertiary referral center. One-hundred-fourty-three ears were included of patients (≥18y) who underwent a CWU tympanomastoidectomy for cholesteatoma with or without bony obliteration between January 2015 and March 2020 in the University Medical Center Utrecht. The median follow-up was respectively 1.4 (IQR 1.1-2.2) vs. 2.0 years (IQR 1.2-3.1) (p = 0.013). Interventions: All patients underwent CWU tympanomastoidectomy for cholesteatoma. For 73 ears bone dust, Bonalive® or a combination was used for obliteration of the mastoid and epitympanic area, the rest of the ears (n = 70) were not obliterated. In accordance with the Dutch protocol, included patients are planned to undergo an MRI scan with diffusion-weighted imaging (DWI) one, three and five years after surgery to detect recurrent or residual cholesteatoma. Main outcome measures: The primary outcome measure was recurrent and residual cholesteatoma as evaluated by MRI-DWI and/or micro-otoscopy and confirmed by micro-otoscopy and/or revision surgery. The secondary outcome measure was the postoperative hearing. Results: In this cohort, the group treated with canal wall up tympanomastoidectomy with subsequent bony obliteration (73 ears, 51.0%) had significantly lower recurrent (4.1%) and residual (6.8%) cholesteatoma rates than the group without obliteration (70 ears, 25.7% and 20.0%, respectively; p < 0.001). There was no significant difference between both groups in postoperative bone conduction thresholds (mean difference 2.7 dB, p = 0.221) as well as the mean air-bone gap closure 6 weeks after surgery (2.3 dB in the non-obliteration and 1.5 dB in the obliteration group, p = 0.903). Conclusions: Based on our results, a canal wall up tympanomastoidectomy with bony obliteration is the treatment of choice, since the recurrent and residual disease rate is lower compared to the group without obliteration. The bony obliteration technique does not seem to affect the perceptive or conductive hearing results, as these are similar between both groups.

Acute effects of cochleostomy and electrode-array insertion on compound action potentials in normal-hearing guinea pigs.

Introduction: Electrocochleography (ECochG) is increasingly used in cochlear implant (CI) surgery, in order to monitor the effect of insertion of the electrode array aiming to preserve residual hearing. However, obtained results are often difficult to interpret. Here we aim to relate changes in ECochG responses to acute trauma induced by different stages of cochlear implantation by performing ECochG at multiple time points during the procedure in normal-hearing guinea pigs. Materials and methods: Eleven normal-hearing guinea pigs received a gold-ball electrode that was fixed in the round-window niche. ECochG recordings were performed during the four steps of cochlear implantation using the gold-ball electrode: (1) Bullostomy to expose the round window, (2) hand-drilling of 0.5-0.6 mm cochleostomy in the basal turn near the round window, (3) insertion of a short flexible electrode array, and (4) withdrawal of electrode array. Acoustical stimuli were tones varying in frequency (0.25-16 kHz) and sound level. The ECochG signal was primarily analyzed in terms of threshold, amplitude, and latency of the compound action potential (CAP). Midmodiolar sections of the implanted cochleas were analyzed in terms of trauma to hair cells, modiolar wall, osseous spiral lamina (OSL) and lateral wall. Results: Animals were assigned to cochlear trauma categories: minimal (n = 3), moderate (n = 5), or severe (n = 3). After cochleostomy and array insertion, CAP threshold shifts increased with trauma severity. At each stage a threshold shift at high frequencies (4-16 kHz) was accompanied with a threshold shift at low frequencies (0.25-2 kHz) that was 10-20 dB smaller. Withdrawal of the array led to a further worsening of responses, which probably indicates that insertion and removal trauma affected the responses rather than the mere presence of the array. In two instances, CAP threshold shifts were considerably larger than threshold shifts of cochlear microphonics, which could be explained by neural damage due to OSL fracture. A change in amplitudes at high sound levels was strongly correlated with threshold shifts, which is relevant for clinical ECochG performed at one sound level. Conclusion: Basal trauma caused by cochleostomy and/or array insertion should be minimized in order to preserve the low-frequency residual hearing of CI recipients.

A monocenter, patient-blinded, randomized, parallel-group, non-inferiority study to compare cochlear implant receiver/stimulator device fixation techniques (COMFIT) with and without drilling in adults eligible for primary cochlear implantation.

BACKGROUND: During the cochlear implantation procedure, the receiver/stimulator (R/S) part of the implant is fixated to prevent postoperative device migration, which could have an adverse effect on the position of the electrode array in the cochlea. We aim to compare the migration rates of two fixation techniques, the bony recess versus the subperiosteal tight pocket without bony sutures. METHODS AND ANALYSIS: This single-blind randomized controlled trial will recruit a total of 112 primary cochlear implantation adult patients, eligible for implantation according to the current standard of practice. Randomization will be performed by an electronic data capture system Castor EDC, with participants block randomized to either bony recess or standard subperiosteal tight pocket in a 1:1 ratio, stratified by age. The primary outcome of this study is the R/S device migration rate; secondary outcomes include patient-experienced burden using the validated COMPASS questionnaire, electrode migration rate, electrode impedance values, speech perception scores, correlation between R/S migration, electrode array migration and patient complaints, assessment of complication rates, and validation of an implant position measurement method. Data will be collected at baseline, 1 week, 4 weeks, 8 weeks, 3 months, and 12 months after surgery. All data analyses will be conducted according to the intention-to-treat principle. DISCUSSION: Cochlear implantation by means of creating a tight subperiosteal pocket without drilling a bony seat is a minimally invasive fixation technique with many advantages. However, the safety of this technique has not yet been proven with certainty. This is the first randomized controlled trial that directly compares the minimally invasive technique with the conventional method of drilling a bony seat. TRIAL REGISTRATION: Netherlands Trial Register NL9698. Registered on 31 August 2021.

The impact of injury of the chorda tympani nerve during primary stapes surgery or cochlear implantation on taste function, quality of life and food preferences: A study protocol for a double-blind prospective prognostic association study.

BACKGROUND: The chorda tympani nerve (CTN) is a mixed nerve, which carries sensory and parasympathetic fibres. The sensory component supplies the taste sensation of the anterior two-thirds of the ipsilateral side of the tongue. During middle ear surgery the CTN is exposed and frequently stretched or sacrificed, because it lacks a bony covering as it passes through the middle ear. Injury may cause hypogeusia, ageusia or altered taste sensation of the ipsilateral side of the tongue. To date, there is no consensus regarding which type of CTN injury (sacrificing or stretching), during middle ear surgery, leads to the least burden for the patient. METHODS: A double-blind prospective prognostic association study was designed in a single medical centre in the Netherlands to determine the effect of CTN injury on postoperative taste disturbance and quality of life. 154 patients, who will undergo primary stapes surgery or cochlear implantation will be included. The taste sensation, food preferences and quality of life of these patients will be evaluated preoperatively and at one week, six weeks and six months postoperatively using the Taste Strip Test, Electrogustometry, supplementary questionnaire on taste disturbance, Macronutrient and Taste Preference Ranking Task, Appetite, Hunger and Sensory Perception questionnaire and Questionnaire of Olfactory Disorders to assess the association of these outcomes with CTN injury. Evaluation of olfactory function will only take place preoperatively and at one week postoperatively using the Sniffin' Sticks. The patient and outcome assessor are blinded to the presence or absence of CTN injury. DISCUSSION: This study is the first to validate and quantify the effect of chorda tympani nerve injury on taste function. The findings of this study may lead to evidence-based proof of the effect of chorda tympani injury on taste function with consequences for surgical strategies. TRIAL REGISTRATION: Netherlands Trial Register NL9791. Registered on 10 October 2021.

Management and Outcomes of Necrotizing Otitis Externa: A Retrospective Cohort Study in a Tertiary Referral Center.

Objectives: Necrotizing otitis externa (NOE) is a rare infection of the ear that causes osteomyelitis. We aimed to evaluate treatment outcomes and the role of imaging in diagnosing and monitoring disease resolution in a single-center study of patients with NOE. Methods: In this retrospective cohort study, patients with NOE who were diagnosed and treated in a tertiary otology center in Utrecht, The Netherlands, between January 1, 2013 and August 1, 2022, were included. Data were retrieved from the medical records on demographics, symptoms, physical and diagnostic findings, type and duration of treatment, and course of disease. Results: A total of 24 cases were included. Patients were often elderly (mean age = 75 years) and diabetic (88%). Pseudomonas aeruginosa was the most commonly found microorganism (63%). Twenty-two cases (92%) received intravenous antibiotic treatment, and 7 cases (29%) received additional systemic antifungal treatment. The mean duration of systemic treatment was 29 weeks. In 20 out of 22 cases (91%), imaging was used to determine the end point of treatment. None of the cases with a total resolution of disease activity (n = 5) on 18F-fluorodeoxyglucose-positron emission tomography-computed tomography imaging at the time of cessation of therapy showed clinical relapse, compared with 1 out of 4 cases on gallium single-photon emission computerized tomography. Conclusion: Based on the experience from our center, we demonstrated that patients with NOE can successfully be treated with prolonged systemic treatment. Molecular imaging is reasonably successful for disease evaluation and decision-making on the eradication of disease.

Cochlear Implant Awareness: Development and Validation of a Patient Reported Outcome Measure.

Background: Surgical success of cochlear implantation is usually measured through speech perception and quality of life questionnaires. Although these questionnaires cover a broad spectrum of domains, they do not evaluate the consciousness of wearing a cochlear implant (CI) and how this impacts the daily life of patients. To evaluate this concept we aimed to develop and validate a standardized patient reported outcome measure (PROM) for use in cochlear implant users. Methods: Development and evaluation of the COchlear iMPlant AwareneSS (COMPASS) questionnaire was realized following the COSMIN guidelines in three phases: (1) item generation, (2) qualitative pilot study to ensure relevance, comprehensiveness, comprehensibility, and face validity, and (3) quantitative survey study for the assessment of reliability (test-retest) with 54 participants. Results: Nine domains of CI awareness were identified through literature research and interviews with experts and patients. These resulted in the formulation of 18 items which were tested with a pilot study, after which 3 items were deleted. The final 15-item COMPASS questionnaire proved to have good validity and satisfactory reliability. The intraclass correlation coefficient calculated for items with continuous variables ranged from 0.66 to 0.89 with seven out of eight items scoring above the acceptable level of 0.7. The Cohen's kappa calculated for items with nominal variables ranged from -0.4 to 0.78 with 11 (sub)items out of 15 scoring above fair to good agreement. Measurement error analysis for items with continuous variables showed a mean difference of -2.18 to 0.22. The calculated 95% limits of agreement for these items revealed no statistically significant difference between the two administered questionnaires. For items with nominal variables, the percentages of agreement calculated, ranged between 0 and 95%, and 83.3 and 96.6% for positive and negative agreement, respectively. Conclusion: The COMPASS questionnaire is a valid and reliable PROM for evaluating the cochlear implant awareness, and it can be easily used in routine clinical practice.

Combined brain-derived neurotrophic factor and neurotrophin-3 treatment is preferred over either one separately in the preservation of the auditory nerve in deafened guinea pigs.

Severe hearing loss or deafness is often caused by cochlear hair cell loss and can be mitigated by a cochlear implant (CI). CIs target the auditory nerve, consisting of spiral ganglion cells (SGCs), which degenerate gradually, following hair cell loss. In animal models, it has been established that treatment with the neurotrophins brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) reduce SGC degeneration. In this study, we aimed to investigate whether treatment with both BDNF and NT-3 (Cocktail) is superior to treatment with each neurotrophin separately regarding cell preservation and neural responsiveness to electrical stimulation. To this end, deafened guinea pigs received neurotrophic treatment in their right ear via a gelatin sponge on the perforated round window membrane, followed by cochlear implantation 4 weeks later in the same ear for electrophysiological recordings to various stimulation paradigms. Normal-hearing and deafened untreated guinea pigs were included as positive and negative controls, respectively. Substantial SGC loss occurred in all deafened animals. Each of the neurotrophic treatments led to enhanced SGC survival mainly in the basal turn of the cochlea, gradually decreasing toward the apex. The Cocktail treatment resulted in the highest SGC survival in the treated ear, followed by BDNF, with the least protection of SGCs following NT-3 treatment. Survival of the SGC's peripheral processes (PPs) followed the same trend in response to the treatment. However, survival of SGCs and PPs in the contralateral untreated ears was also highest in the Cocktail group. Consequently, analysis of the ratio between the treated and untreated ears showed that the BDNF group, which showed low SGC survival in the untreated ear, had the highest relative SGC survival of the three neurotrophin-treated groups. Neurotrophic treatment had positive effects in part of the electrically evoked compound action-potential recording paradigms. These effects were only observed for the BDNF or Cocktail treatment. We conclude that treatment with either BDNF or a cocktail of BDNF and NT-3 is preferred to NT-3 alone. Furthermore, since the Cocktail treatment resulted in better electrophysiological responsiveness and overall higher SGC survival than BDNF alone, we are inclined to recommend the Cocktail treatment rather than BDNF alone.

The effect of the surgical approach and cochlear implant electrode on the structural integrity of the cochlea in human temporal bones.

Cochlear implants (CI) restore hearing of severely hearing-impaired patients. Although this auditory prosthesis is widely considered to be very successful, structural cochlear trauma during cochlear implantation is an important problem, reductions of which could help to improve hearing outcomes and to broaden selection criteria. The surgical approach in cochlear implantation, i.e. round window (RW) or cochleostomy (CO), and type of electrode-array, perimodiolar (PM) or lateral wall (LW), are variables that might influence the probability of severe trauma. We investigated the effect of these two variables on scalar translocation (STL), a specific type of severe trauma. Thirty-two fresh frozen human cadaveric ears were evenly distributed over four groups receiving either RW or CO approach, and either LW or PM array. Conventional radiological multiplanar reconstruction (MPR) was compared with a reconstruction method that uncoils the spiral shape of the cochlea (UCR). Histological analysis showed that RW with PM array had STL rate of 87% (7/8), CO approach with LW array 75% (6/8), RW approach with LW array 50% (4/8) and CO approach with PM array 29% (2/7). STL assessment using UCR showed a higher inter-observer and histological agreement (91 and 94% respectively), than that using MPR (69 and 74% respectively). In particular, LW array positions were difficult to assess with MPR. In conclusion, the interaction between surgical approach and type of array should be preoperatively considered in cochlear implant surgery. UCR technique is advised for radiological assessment of CI positions, and in general it might be useful for pathologies involving the inner ear or other complex shaped bony tubular structures.