Delayed hearing loss after cochlear implantation: Re-evaluating the role of hair cell degeneration.

Delayed loss of residual acoustic hearing after cochlear implantation is a common but poorly understood phenomenon due to the scarcity of relevant temporal bone tissues. Prior histopathological analysis of one case of post-implantation hearing loss suggested there were no interaural differences in hair cell or neural degeneration to explain the profound loss of low-frequency hearing on the implanted side (Quesnel et al., 2016) and attributed the threshold elevation to neo-ossification and fibrosis around the implant. Here we re-evaluated the histopathology in this case, applying immunostaining and improved microscopic techniques for differentiating surviving hair cells from supporting cells. The new analysis revealed dramatic interaural differences, with a > 80 % loss of inner hair cells in the cochlear apex on the implanted side, which can account for the post-implantation loss of residual hearing. Apical degeneration of the stria further contributed to threshold elevation on the implanted side. In contrast, spiral ganglion cell survival was reduced in the region of the electrode on the implanted side, but apical counts in the two ears were similar to that seen in age-matched unimplanted control ears. Almost none of the surviving auditory neurons retained peripheral axons throughout the basal half of the cochlea. Relevance to cochlear implant performance is discussed.

Intracochlear Trauma and Local Ossification Patterns Differ Between Straight and Precurved Cochlear Implant Electrodes.

HYPOTHESIS: Trauma to the osseous spiral lamina (OSL) or spiral ligament (SL) during cochlear implant (CI) insertion segregates with electrode type and induces localized intracochlear ossification and fibrosis. BACKGROUND: The goal of atraumatic CI insertion is to preserve intracochlear structures, limit reactive intracochlear tissue formation, and preserve residual hearing. Previous qualitative studies hypothesized a localized effect of trauma on intracochlear tissue formation; however, quantitative studies failed to confirm this. METHODS: Insertional trauma beyond the immediate insertion site was histologically assessed in 21 human temporal bones with a CI. Three-dimensional reconstructions were generated and virtually resectioned perpendicular to the cochlear spiral at high resolution. The cochlear volume occupied by ossification or fibrosis was determined at the midpoint of the trauma and compared with regions proximal and distal to this point. RESULTS: Seven cases, all implanted with precurved electrodes, showed an OSL fracture beyond the immediate insertion site. Significantly more intracochlear ossification was observed at the midpoint of the OSL fracture, compared with the -26 to -18 degrees proximal and 28 to 56 degrees distal to the center. No such pattern was observed for fibrosis. In the 12 cases with a perforation of the SL (9 straight and 3 precurved electrodes), no localized pattern of ossification or fibrosis was observed around these perforations. CONCLUSION: OSL fractures were observed exclusively with precurved electrodes in this study and may serve as a nidus for localized intracochlear ossification. Perforation of the SL, in contrast, predominantly occurred with straight electrodes and was not associated with localized ossification.

Human Histology after Structure Preservation Cochlear Implantation via Round Window Insertion.

OBJECTIVES: Current surgical techniques aim to preserve intracochlear structures during cochlear implant (CI) insertion to maintain residual cochlear function. The optimal technique to minimize damage, however, is still under debate. The aim of this study is to histologically compare insertional trauma and intracochlear tissue formation in humans with a CI implanted via different insertion techniques. METHODS: One recent temporal bone from a donor who underwent implantation of a full-length CI (576°) via round window (RW) insertion was compared with nine cases implanted via cochleostomy (CO) or extended round window (ERW) approach. Insertional trauma was assessed on H&E-stained histological sections. 3D reconstructions were generated and virtually re-sectioned to measure intracochlear volumes of fibrosis and neo-ossification. RESULTS: The RW insertion case showed electrode translocation via the spiral ligament. 2/9 CO/ERW cases showed no insertional trauma. The total volume of the cochlea occupied by fibro-osseous tissue was 10.8% in the RW case compared with a mean of 30.6% (range 8.7%-44.8%, N = 9) in the CO/ERW cases. The difference in tissue formation in the basal 5 mm of scala tympani, however, was even more pronounced when the RW case (12.3%) was compared with the cases with a CO/ERW approach (mean of 93.8%, range 81% to 100%, N = 9). CONCLUSIONS: Full-length CI insertions via the RW can be minimally traumatic at the cochlear base without inducing extensive fibro-osseous tissue formation locally. The current study further supports the hypothesis that drilling of the cochleostomy with damage to the endosteum incites a local tissue reaction. LEVEL OF EVIDENCE: 4: Case-control study Laryngoscope, 134:945-953, 2024.

Incomplete Partition Type II Cochlear Malformations: Delineating the Three-Dimensional Structure from Digitized Human Histopathological Specimens.

HYPOTHESIS: There are clinically relevant differences in scalae anatomy and spiral ganglion neuron (SGN) quantity between incomplete partition type II (IP-II) and normal cochleae. BACKGROUND: IP-II is a commonly implanted cochlear malformation. Detailed knowledge of intracochlear three-dimensional (3D) morphology may assist with cochlear implant (CI) electrode selection/design and enable optimization of audiologic programming based on SGN maps. METHODS: IP-II (n = 11) human temporal bone histological specimens were identified from the National Institute on Deafness and Other Communication Disorders National Temporal Bone Registry and digitized. The cochlear duct, scalae, and surgically relevant anatomy were reconstructed in 3D. A machine learning algorithm was applied to map the location and number of SGNs. RESULTS: 3D scalae morphology of the basal turn was normal. Scala tympani (ST) remained isolated for 540 degrees before fusing with scala vestibuli. Mean ST volume reduced below 1 mm 2 after the first 340 degrees. Scala media was a distinct endolymphatic compartment throughout; mean ± standard deviation cochlear duct length was 28 ± 3 mm. SGNs were reduced compared with age-matched norms (mean, 48%; range, 5-90%). In some cases, SGNs failed to ascend Rosenthal's canal, remaining in an abnormal basalward modiolar location. Two forms of IP-II were seen: type A and type B. A majority (98-100%) of SGNs were located in the basal modiolus in type B IP-II, compared with 76 to 85% in type A. CONCLUSION: Hallmark features of IP-II cochleae include the following: 1) fusion of the ST and scala vestibuli at a mean of 540 degrees, 2) highly variable and overall reduced SGN quantity compared with normative controls, and 3) abnormal SGN distribution with cell bodies failing to ascend Rosenthal's canal.

Cochlear Ossification After Vestibular Schwannoma Surgery: A Temporal Bone Study.

OBJECTIVE: This study aims to investigate patterns of cochlear ossification (CO) in cadaveric temporal bones of patients who underwent vestibular schwannoma (VS) surgery via the translabyrinthine (TL), middle cranial fossa (MF), or retrosigmoid (RS) approaches. STUDY DESIGN: Histopathologic analysis of cadaveric temporal bones. SETTING: Multi-institutional national temporal bone repository. METHODS: The National Institute of Deafness and Communication Disorders and House Temporal Bone Laboratory at the University of California, Los Angeles and the Massachusetts Eye and Ear Otopathology Laboratory were searched for cadaveric temporal bones with a history of VS for which microsurgery was performed. Exclusion criteria included non-VS and perioperative death within 30 days of surgery. Temporal bones were analyzed histologically for CO of the basal, middle, and apical turns. RESULTS: Of 92 temporal bones with a history of schwannoma from both databases, 12 of these cases met the inclusion criteria. The approaches for tumor excision included 2 MF, 4 RS, and 6 TL approaches. CO was observed in all temporal bones that had undergone TL surgery. Among temporal bones that had undergone MF or RS surgeries, 5/6 had no CO, and 1/6 had partial ossification. This single case was noted to have intraoperative vestibular violation after RS surgery upon histopathologic and chart review. CONCLUSION: In this temporal bone series, all temporal bones that had undergone TL demonstrated varying degrees of CO on histological analysis. MF and RS cases did not exhibit CO except in the case of vestibular violation. When cochlear implantation is planned or possible after VS surgery, surgeons may consider using a surgical approach that does not violate the labyrinth.

Development of an interdisciplinary microtia-atresia care model: A single-center 20-year experience.

Objectives: Microtia and aural atresia are congenital ear anomalies with a wide-ranging spectrum of phenotypes and varied functional and psychosocial consequences for patients. This study seeks to analyze the management of microtia-atresia patients at our center over a 20-year period and to propose recommendations for advancing microtia-atresia care at a national level. Methods: We performed a retrospective analysis of data from patients presenting to the Massachusetts Eye and Ear (Boston, MA) for initial otolaryngology consultation for congenital microtia and/or aural atresia between 1999 and 2018. Results: Over the 20-year study period, 229 patients presented to our microtia-atresia center at a median age of 7 years. The severity of microtia was most commonly classified as grade III (n = 87, 38%), 61% (n = 140) of patients had complete atresia, the median Jahrsdoerfer grading scale score was 6 (range 0-10), and 81 patients (35%) underwent surgery for microtia repair. For hearing rehabilitation, 30 patients (64%) underwent bone conduction device implantation and 17 patients (36%) underwent atresiaplasty. The implementation of an interdisciplinary, longitudinal care model resulted in an increase in patient (r = 0.819, p < .001) and surgical volume (microtia surgeries, r = 0.521, p = .019; otologic surgeries, r = 0.767, p < .001) at our center over time. Conclusion: An interdisciplinary team approach to microtia-atresia patient care may result in increased patient volume, which could improve aesthetic and hearing outcomes over time by concentrating care and surgical expertise. Future work should aim to establish standardized clinical consensus recommendations to guide the creation of high-quality microtia-atresia care programs. Level of Evidence: 4.

Voluntary Field Recall of Advanced Bionics HiRes Cochlear Implants: A Single-Institution Experience.

OBJECTIVES: In 2020, Advanced Bionics (AB) announced a recall of two cochlear implant (CI) models, the "HiRes Ultra" and "HiRes Ultra 3D", because of reports of hearing degradation. The present study examines clinical parameters and patient features in cases of device failure and evaluates outcomes after reimplantation. MATERIALS AND METHODS: A series of 52 patients implanted with the recalled devices experienced suspected device failure and subsequently underwent revision CI placement at a tertiary academic medical center between December 2019 and November 2021. RESULTS: Consonant-nucleus-consonant scores and individual phonemes increased significantly between patients' preoperative evaluation and primary cochlear implantation. Performance declined significantly before revision and recovered after revision CI placement. Similarly, pure-tone average thresholds improved between preoperative and primary CI, fell before revision surgery, and were corrected with revision implantation. As a group, patients reached their peak hearing performance significantly faster after revision CI (mean ± standard deviation, 53.4 ± 51.8 d) compared with their primary CI (mean ± standard deviation, 260.6 ± 245.9 d). Electrical field imaging performed by AB and device impedance measurements were found to be abnormal in the basally positioned electrodes (electrodes 9-16). CONCLUSION: Hearing performance degradation is significant in AB Ultra device failures and seems to be linked to the basal-most electrodes in the array. Revision outcomes have been robust, necessitating continued monitoring of affected patients and support for reimplantation procedures. LEVEL OF EVIDENCE: IV.

Otopathologic and Computed Tomography Correlation of Internal Auditory Canal Diverticula in Otosclerosis.

INTRODUCTION: Internal auditory canal (IAC) diverticula, also known as IAC cavitary lesions or anterior cupping of the IAC, observed in otopathologic specimens and high-resolution computed tomography (CT) scans of the temporal bone are thought to be related to otosclerosis. Herein, we examined the usefulness of CT scans in identifying diverticula and determined whether IAC diverticula are associated with otosclerosis on otopathology. METHODS: One hundred five consecutive specimens were identified from the National Temporal Bone Hearing and Balance Pathology Resource Registry. Inclusion criteria included the availability of histologic slides and postmortem specimen CT scans. Exclusion criteria included cases with severe postmortem changes or lesions causing bony destruction of the IAC. RESULTS: Ninety-seven specimens met criteria for study. Of these, 42% of the specimens were from male patients, and the average age of death was 77 years (SD = 18 yr). IAC diverticula were found in 48 specimens, of which 46% were identified in the CT scans. The mean area of the IAC diverticula was 0.34 mm 2 . The sensitivity and specificity of detecting IAC diverticula based on CT were 77% and 63%, respectively. Overall, 27% of specimens had otosclerosis. Histologic IAC diverticula were more common in specimens with otosclerosis than those without (37.5% versus 16%; p = 0.019). Cases with otosclerosis had a greater mean histologic diverticula area compared with nonotosclerosis cases (0.69 mm 2 versus 0.14 mm 2 ; p = 0.001). CONCLUSION: IAC diverticula are commonly found in otopathologic specimens with varied etiologies, but larger diverticula are more likely to be associated with otosclerosis. The sensitivity and specificity of CT scans to detect IAC diverticula are limited.

Cochlear implants: Causes, effects and mitigation strategies for the foreign body response and inflammation.

Cochlear implants provide effective auditory rehabilitation for patients with severe to profound sensorineural hearing loss. Recent advances in cochlear implant technology and surgical approaches have enabled a greater number of patients to benefit from this technology, including those with significant residual low frequency acoustic hearing. Nearly all cochleae implanted with a cochlear implant electrode array develop an inflammatory and fibrotic response. This tissue reaction can have deleterious consequences for implant function, residual acoustic hearing, and the development of the next generation of cochlear prosthetics. This article reviews the current understanding of the inflammatory/foreign body response (FBR) after cochlear implant surgery, its impact on clinical outcome, and therapeutic strategies to mitigate this response. Findings from both in human subjects and animal models across a variety of species are highlighted. Electrode array design, surgical techniques, implant materials, and the degree and type of electrical stimulation are some critical factors that affect the FBR and inflammation. Modification of these factors and various anti-inflammatory pharmacological interventions have been shown to mitigate the inflammatory/FBR response. Ongoing and future approaches that seek to limit surgical trauma and curb the FBR to the implanted biomaterials of the electrode array are discussed. A better understanding of the anatomical, cellular and molecular basis of the inflammatory/FBR response after cochlear implantation has the potential to improve the outcome of current cochlear implants and also facilitate the development of the next generation of neural prostheses.

Computed Tomography Density as a Bio-marker for Histologic Grade of Otosclerosis: A Human Temporal Bone Pathology Study.

HYPOTHESIS: Computed tomography (CT) density measurement can be used to objectively distinguish otosclerosis from normal bone and to determine histologic grades of otosclerosis. BACKGROUND: Otosclerosis can be seen on CT as subtle radiolucent areas. An objective radiologic measurement that corresponds to known otosclerosis pathology may improve diagnostic accuracy, and could be used as a radiologic biomarker for otosclerosis grade. METHODS: A blinded, randomized evaluation of both histologic grade on histopathology slides and CT density measurement was performed on 78 human temporal bone specimens (31 with otosclerosis and 47 controls) that had undergone high-resolution multi-detector CT before histologic processing. Assessments were performed at 11 regions of interest (ROIs) in the otic capsule for each specimen. RESULTS: The CT density measurement mean (Hounsfield Units) ± standard deviation for all ROIs (Nos. 1-9) was 2245 ± 854 for grade 0 (no otosclerosis, n = 711), 1896 ± 317 for grade 1 (inactive otosclerosis, n = 109), and 1632 ± 255 for grades 2 and 3 combined (mixed/active otosclerosis, n 35). There was a strong inverse correlation of CT density to histologic grade at ROIs Nos. 1-5 (ANOVA, p < 0.0001). The inter-rater reliability for CT density was very good (correlation coefficient 0.87, p < 0.05). ROC curves suggested a cut-off of 2,150HU to distinguish otosclerosis from normal bone, and 1,811HU to distinguish low grade from mixed/high grade otosclerosis. CONCLUSIONS: In human temporal bone specimens, CT density may be used to distinguish normal bone from bone involved by otosclerosis. A higher histologic grade (i.e., indicating a more active otosclerotic focus) correlated with lower density.

Assessment of Sudden Sensorineural Hearing Loss After COVID-19 Vaccination.

IMPORTANCE: Emerging reports of sudden sensorineural hearing loss (SSNHL) after COVID-19 vaccination within the otolaryngological community and the public have raised concern about a possible association between COVID-19 vaccination and the development of SSNHL. OBJECTIVE: To examine the potential association between COVID-19 vaccination and SSNHL. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study and case series involved an up-to-date population-based analysis of 555 incident reports of probable SSNHL in the Centers for Disease Control and Prevention Vaccine Adverse Events Reporting System (VAERS) over the first 7 months of the US vaccination campaign (December 14, 2020, through July 16, 2021). In addition, data from a multi-institutional retrospective case series of 21 patients who developed SSNHL after COVID-19 vaccination were analyzed. The study included all adults experiencing SSNHL within 3 weeks of COVID-19 vaccination who submitted reports to VAERS and consecutive adult patients presenting to 2 tertiary care centers and 1 community practice in the US who were diagnosed with SSNHL within 3 weeks of COVID-19 vaccination. EXPOSURES: Receipt of a COVID-19 vaccine produced by any of the 3 vaccine manufacturers (Pfizer-BioNTech, Moderna, or Janssen/Johnson & Johnson) used in the US. MAIN OUTCOMES AND MEASURES: Incidence of reports of SSNHL after COVID-19 vaccination recorded in VAERS and clinical characteristics of adult patients presenting with SSNHL after COVID-19 vaccination. RESULTS: A total of 555 incident reports in VAERS (mean patient age, 54 years [range, 15-93 years]; 305 women [55.0%]; data on race and ethnicity not available in VAERS) met the definition of probable SSNHL (mean time to onset, 6 days [range, 0-21 days]) over the period investigated, representing an annualized incidence estimate of 0.6 to 28.0 cases of SSNHL per 100 000 people per year. The rate of incident reports of SSNHL was similar across all 3 vaccine manufacturers (0.16 cases per 100 000 doses for both Pfizer-BioNTech and Moderna vaccines, and 0.22 cases per 100 000 doses for Janssen/Johnson & Johnson vaccine). The case series included 21 patients (mean age, 61 years [range, 23-92 years]; 13 women [61.9%]) with SSNHL, with a mean time to onset of 6 days (range, 0-15 days). Patients were heterogeneous with respect to clinical and demographic characteristics. Preexisting autoimmune disease was present in 6 patients (28.6%). Of the 14 patients with posttreatment audiometric data, 8 (57.1%) experienced improvement after receiving treatment. One patient experienced SSNHL 14 days after receiving each dose of the Pfizer-BioNTech vaccine. CONCLUSIONS AND RELEVANCE: In this cross-sectional study, findings from an updated analysis of VAERS data and a case series of patients who experienced SSNHL after COVID-19 vaccination did not suggest an association between COVID-19 vaccination and an increased incidence of hearing loss compared with the expected incidence in the general population.

International Survey of Operative Practices for Otologists and Neurotologists During the COVID-19 Crisis.

OBJECTIVE: To investigate the influence of the COVID-19 pandemic on operative practices of otology and neurotology providers internationally. STUDY DESIGN: Cross-sectional survey. METHODS: A 78-question survey was distributed to otologists and neurotologists between May 12, 2020 and June 8, 2020 to assess the impact of the pandemic on surgical practices. Sections within the survey delineated time periods: prior to the crisis, onset of the crisis, during the crisis, postcrisis transition. RESULTS: Of 396 survey respondents, 284 participants from 38 countries met inclusion criteria.Respondents were 16.9% female and 82.4% male, with a most common age range of 40 to 49 years (36.3%). 69.8% of participants had been in practice for over 10 years and most respondents worked in an academic medical center (79.2%). The average operative weekly caseload was 5.3 (SD 3.9) per surgeon prior to the crisis, 0.7 (SD 1.2) during the COVID-19 crisis, and 3.5 (SD 3.3) for those who had begun a postcrisis transition at the time of survey administration (p < 0.001). 71.5% of providers did not perform an elective otologic or neurotologic operative procedure during the initial crisis period. 49.8% reported modifying their surgical technique due to the COVID-19 pandemic. Use of powered air-purifying respirators and filtering facepiece 2 or 3 (FFP2/FFP3) respirators were in minimal supply for 66.9% and 62.3% of respondents, respectively. CONCLUSION: The COVID-19 pandemic impacted the otology and neurotology community globally, resulting in significant changes in operative volume and case selection. Modification of surgical technique and shortages of personal protective equipment were frequently reported.

The Pathology of the Vestibular System in CANVAS.

OBJECTIVE: To describe the site of lesion responsible for the severe, bilateral, symmetrical, selective loss of vestibular function in Cerebellar Ataxia with Neuronopathy and Vestibular Areflexia Syndrome (CANVAS), an adult-onset recessively-inherited ataxia, characterized by progressive imbalance due to a combination of cerebellar, somatosensory, and selective vestibular impairment with normal hearing. METHODS: Histologic examination of five temporal bones and the brainstems from four CANVAS patients and the brainstem only from one more, each diagnosed and followed from diagnosis to death by one of the clinician authors. RESULTS: All five temporal bones showed severe loss of vestibular ganglion cells (cell counts 3-16% of normal), and atrophy of the vestibular nerves, whereas vestibular receptor hair cells and the vestibular nuclei were preserved. In contrast, auditory receptor hair cells, the auditory ganglia (cell counts 51-100% of normal), and the auditory nerves were relatively preserved. In addition, the cranial sensory ganglia (geniculate and trigeminal), present in two temporal bones, also showed severe degeneration. CONCLUSIONS: In CANVAS there is a severe cranial sensory ganglionopathy neuronopathy (ganglionopathy) involving the vestibular, facial, and trigeminal ganglia but sparing the auditory ganglia. These observations, when coupled with the known spinal dorsal root ganglionopathy in CANVAS, indicate a shared pathogenesis of its somatosensory and cranial nerve manifestations. This is the first published account of both the otopathology and neuropathology of CANVAS, a disease that involves the central as well as the peripheral nervous system.

Aerosol Dispersion During Mastoidectomy and Custom Mitigation Strategies for Otologic Surgery in the COVID-19 Era.

OBJECTIVE: To investigate small-particle aerosolization from mastoidectomy relevant to potential viral transmission and to test source-control mitigation strategies. STUDY DESIGN: Cadaveric simulation. SETTING: Surgical simulation laboratory. METHODS: An optical particle size spectrometer was used to quantify 1- to 10-µm aerosols 30 cm from mastoid cortex drilling. Two barrier drapes were evaluated: OtoTent1, a drape sheet affixed to the microscope; OtoTent2, a custom-structured drape that enclosed the surgical field with specialized ports. RESULTS: Mastoid drilling without a barrier drape, with or without an aerosol-scavenging second suction, generated large amounts of 1- to 10-µm particulate. Drilling under OtoTent1 generated a high density of particles when compared with baseline environmental levels (P < .001, U = 107). By contrast, when drilling was conducted under OtoTent2, mean particle density remained at baseline. Adding a second suction inside OtoTent1 or OtoTent2 kept particle density at baseline levels. Significant aerosols were released upon removal of OtoTent1 or OtoTent2 despite a 60-second pause before drape removal after drilling (P < .001, U = 0, n = 10, 12; P < .001, U = 2, n = 12, 12, respectively). However, particle density did not increase above baseline when a second suction and a pause before removal were both employed. CONCLUSIONS: Mastoidectomy without a barrier, even when a second suction was added, generated substantial 1- to 10-µm aerosols. During drilling, large amounts of aerosols above baseline levels were detected with OtoTent1 but not OtoTent2. For both drapes, a second suction was an effective mitigation strategy during drilling. Last, the combination of a second suction and a pause before removal prevented aerosol escape during the removal of either drape.

Histopathologic Evaluation of Intralabyrinthine Schwannoma.

OBJECTIVES: The aim of this study is to perform a histopathologic analysis of temporal bones with an intralabyrinthine schwannoma (ILS) in order to characterize its extension. METHODS: Archival temporal bones with a diagnosis of sporadic schwannoma were identified. Both symptomatic and occult nonoperated ILS were included for further analysis. RESULTS: A total of 6 ILS were identified, with 4 intracochlear and 2 intravestibular schwannomas. All intracochlear schwannomas involved the osseous spiral lamina, with 2 extending into the modiolus. The intravestibular schwannomas were limited to the vestibule, but growth into the bone next to the crista of the lateral semicircular canal was observed in 1 patient. CONCLUSIONS: Complete removal of an ILS may require partial removal of the modiolus or bone surrounding the crista ampullaris as an ILS may extend into these structures, risking damage of the neuronal structures. Due to the slow growth of the ILS, it remains unclear if a complete resection is required with the risk of destroying neural structures hindering hearing rehabilitation with a cochlear implant.

Teaching Endoscopic Ear Surgery.

Endoscopic ear surgery (EES) has become an integral part of otologic surgery. Training in EES involves learning fundamental techniques for endoscopic visualization, becoming proficient at one-handed dissection, mastering use of instruments designed for endoscopic ear surgery, and learning to optimize the operating room setup specifically for EES. Despite the steep learning curve, EES offers several advantages over the microscope for otologic procedures. With the rise in the demand for minimally invasive approaches, EES has a clear role in the future of otologic surgery. Identifying strategies to improve the training process of EES for the novice and experienced otolaryngologist is paramount.

American Neurotology Society, American Otological Society, and American Academy of Otolaryngology - Head and Neck Foundation Guide to Enhance Otologic and Neurotologic Care During the COVID-19 Pandemic.

: This combined American Neurotology Society, American Otological Society, and American Academy of Otolaryngology - Head and Neck Surgery Foundation document aims to provide guidance during the coronavirus disease of 2019 (COVID-19) on 1) "priority" of care for otologic and neurotologic patients in the office and operating room, and 2) optimal utilization of personal protective equipment. Given the paucity of evidence to inform otologic and neurotologic best practices during COVID-19, the recommendations herein are based on relevant peer-reviewed articles, the Centers for Disease Control and Prevention COVID-19 guidelines, United States and international hospital policies, and expert opinion. The suggestions presented here are not meant to be definitive, and best practices will undoubtedly change with increasing knowledge and high-quality data related to COVID-19. Interpretation of this guidance document is dependent on local factors including prevalence of COVID-19 in the surgeons' local community. This is not intended to set a standard of care, and should not supersede the clinician's best judgement when managing specific clinical concerns and/or regional conditions.Access to otologic and neurotologic care during and after the COVID-19 pandemic is dependent upon adequate protection of physicians, audiologists, and ancillary support staff. Otolaryngologists and associated staff are at high risk for COVID-19 disease transmission based on close contact with mucosal surfaces of the upper aerodigestive tract during diagnostic evaluation and therapeutic procedures. While many otologic and neurotologic conditions are not imminently life threatening, they have a major impact on communication, daily functioning, and quality of life. In addition, progression of disease and delay in treatment can result in cranial nerve deficits, intracranial and life-threatening complications, and/or irreversible consequences. In this regard, many otologic and neurotologic conditions should rightfully be considered "urgent," and almost all require timely attention to permit optimal outcomes. It is reasonable to proceed with otologic and neurotologic clinic visits and operative cases based on input from expert opinion of otologic care providers, clinic/hospital administration, infection prevention and control specialists, and local and state public health leaders. Significant regional variations in COVID-19 prevalence exist; therefore, physicians working with local municipalities are best suited to make determinations on the appropriateness and timing of otologic and neurotologic care.

Demonstration and Mitigation of Aerosol and Particle Dispersion During Mastoidectomy Relevant to the COVID-19 Era.

BACKGROUND: COVID-19 has become a global pandemic with a dramatic impact on healthcare systems. Concern for viral transmission necessitates the investigation of otologic procedures that use high-speed drilling instruments, including mastoidectomy, which we hypothesized to be an aerosol-generating procedure. METHODS: Mastoidectomy with a high-speed drill was simulated using fresh-frozen cadaveric heads with fluorescein solution injected into the mastoid air cells. Specimens were drilled for 1-minute durations in test conditions with and without a microscope. A barrier drape was fashioned from a commercially available drape (the OtoTent). Dispersed particulate matter was quantified in segments of an octagonal test grid measuring 60 cm in radius. RESULTS: Drilling without a microscope dispersed fluorescent particles 360 degrees, with the areas of highest density in quadrants near the surgeon and close to the surgical site. Using a microscope or varying irrigation rates did not significantly reduce particle density or percent surface area with particulate. Using the OtoTent significantly reduced particle density and percent surface area with particulate across the segments of the test grid beyond 30 cm (which marked the boundary of the OtoTent) compared with the microscope only and no microscope test conditions (Kruskall-Wallis test, p = 0.0066). CONCLUSIONS: Mastoidectomy with a high-speed drill is an aerosol-generating procedure, a designation that connotes the potential high risk of viral transmission and need for higher levels of personal protective equipment. A simple barrier drape significantly reduced particulate dispersion in this study and could be an effective mitigation strategy in addition to appropriate personal protective equipment.