Alzheimer's Disease-Related Analytes Amyloid-ß and Tau in Perilymph: Correlation With Patient Age and Cognitive Score.

OBJECTIVE: To describe the collection methods for perilymph fluid biopsy during cochlear implantation, detect levels of amyloid ß 42 and 40 (Aß42 and Aß40), and total tau (tTau) analytes with a high-precision assay, to compare these levels with patient age and Montreal Cognitive Assessment (MoCA) scores, and explore potential mechanisms and relationships with otic pathology. STUDY DESIGN: Prospective study. SETTING: Tertiary referral center. METHODS: Perilymph was collected from 25 patients using polyimide tubing to avoid amyloid adherence to glass, and analyzed with a single-molecule array advanced digital enzyme-linked immunosorbent assay platform for Aß40, Aß42, and tTau. Cognition was assessed by MoCA. RESULTS: Perilymph volumes ranged from ∼1 to 13 µL, with analyte concentrations spanning 2.67 to 1088.26 pg/mL. All samples had detectable levels of tTau, Aß40, and Aß42, with a significant positive correlation between Aß42 and Aß40 levels. Levels of Aß42, Aß40, and tTau were positively correlated with age, while MoCA scores were inversely correlated with age. tTau and Aß42/Aß40-ratios were significantly correlated with MoCA scores. CONCLUSION: Alzheimer's disease-associated peptides Aß42, Aß40, and tau analytes are detectable in human perilymph at levels approximately 10-fold lower than those found in cerebrospinal fluid (CSF). These species increase with age and correlate with cognitive impairment indicators, suggesting their potential utility as biomarkers for cognitive impairment in patients undergoing cochlear implantation. Future research should investigate the origin of these analytes in the perilymph and their potential links to inner ear pathologies and hearing loss, as well as their relationships to CSF and plasma levels in individuals.

Single-cell multi-omic analysis of the vestibular schwannoma ecosystem uncovers a nerve injury-like state.

Vestibular schwannomas (VS) are benign tumors that lead to significant neurologic and otologic morbidity. How VS heterogeneity and the tumor microenvironment (TME) contribute to VS pathogenesis remains poorly understood. In this study, we perform scRNA-seq on 15 VS, with paired scATAC-seq (n = 6) and exome sequencing (n = 12). We identify diverse Schwann cell (SC), stromal, and immune populations in the VS TME and find that repair-like and MHC-II antigen-presenting SCs are associated with myeloid cell infiltrate, implicating a nerve injury-like process. Deconvolution analysis of RNA-expression data from 175 tumors reveals Injury-like tumors are associated with larger tumor size, and scATAC-seq identifies transcription factors associated with nerve repair SCs from Injury-like tumors. Ligand-receptor analysis and in vitro experiments suggest that Injury-like VS-SCs recruit myeloid cells via CSF1 signaling. Our study indicates that Injury-like SCs may cause tumor growth via myeloid cell recruitment and identifies molecular pathways that may be therapeutically targeted.

Identifying Slim Modiolar Electrode Tip Fold-Over With Intracochlear Electrocochleography.

OBJECTIVE: To evaluate the predictive value of intracochlear electrocochleography (ECochG) for identifying tip fold-over during cochlear implantation (CI) using the slim modiolar electrode (SME) array. STUDY DESIGN: Prospective cohort study. SETTING: Tertiary referral center. METHODS: From July 2022 to June 2023, 142 patients, including adults and children, underwent intracochlear ECochG monitoring during and after SME placement. Tone-bursts were presented from 250 Hz to 2 kHz at 108 to 114 dB HL. A fast Fourier transform (FFT) allowed for frequency-specific evaluation of ECochG response. ECochG patterns during insertion and postinsertion were evaluated using sensitivity and specificity analysis to predict tip fold-over. Intraoperative plain radiographs served as a reference standard. RESULTS: Fifteen tip fold-over cases occurred (10.6%) with significant ECochG response (>2 µV). Sixty-one cases without tip fold-over occurred (43.0%) with significant ECochG response. All tip fold-overs had both a nontonotopic postinsertion sweep and nonrobust active insertion pattern. No patients with robust insertion or tonotopic sweep patterns had tip fold-over. Sensitivity of detecting tip fold-over when having both nonrobust insertion and nontonotopic sweep patterns was 100% (95% confidence inteval [CI] 78.2%-100%), specificity was 68.9% (95% CI 55.7%-80.1%), and the overall accuracy was 72.0% (95% CI 60.5%-81.7%). CONCLUSION: Intracochlear ECochG monitoring during cochlear implantation with the SME can be a valuable tool for identifying properly positioned electrode arrays. In cases where ECochG patterns are nonrobust on insertion and nontonotopic for electrode sweeps, there may be a concern for tip fold-over, and intraoperative imaging is necessary to confirm proper insertion.

One-Year Hearing Preservation and Speech Outcomes Comparing Slim Modiolar and Lateral Wall Arrays.

OBJECTIVE: Compare postoperative speech outcomes in hearing preservation (HP) cochlear implantation (CI) patients with a low-frequency pure-tone average (LFPTA) ≤ 60 dB using 2 electrode array designs. STUDY DESIGN: Retrospective cohort study. SETTING: Large academic cochlear implant referral center. METHODS: We reviewed adult HP CI cases using either the slim modiolar electrode (SME) (CI 532/CI 632) or th slim lateral wall electrode (SLWE) (CI 624). One-year speech outcomes and HP status were the primary outcomes. RESULTS: A total of 132 implanted ears were analyzed (mean age 73.1 years, standard deviation [SD] 12.6), with 72% (N = 95) with CI 532/632 and 28% (N = 37) with CI 624. The mean preoperative LFPTA was 44.8 dB, SD 11.8. One-year functional HP was 27.2% (mean LFPTA shift 46.1 dB, SD 22.1) and was as follows: SME 23.9% and SLWE 36.4%, p = .168. The mean age at implantation was significantly younger only in SLWE patients with preserved hearing (66.9 vs 80.3 years, p = .008). At 6 months, speech measures were significantly better in all outcomes in HP patients with an SLWE than nonpreserved SLWE patients; this effect abated at 1 year as performance among nonpreserved SLWE patients became equivalent to the remaining cohort. Speech outcomes in SME patients were similar regardless of HP status. Age at implantation and datalogging was correlated with speech outcomes. CONCLUSION: In this cohort of HP patients, a 1-year functional HP rate of 23.9% (SME) and 36.4% (SLWE) was observed (p = 0.168). This was initially 57.1% (SME) and 70.3% (SLWE) at activation, p = .172. Datalogging and age at implantation were correlated with postoperative speech outcomes.

Incidence and Management of Facial Paralysis After Skull Base Trauma, an Administrative Database Study.

OBJECTIVE: Report the incidence of and treatment patterns for facial nerve palsy after skull base fracture. STUDY DESIGN: Retrospective cohort study. SETTING: IBM MarketScan Commercial Database (2006-2019). PATIENTS: Human subjects with skull base fracture, per International Classification of Diseases-9th and 10th Revisions-Clinical Modification diagnosis codes. MAIN OUTCOME MEASURES: The primary outcomes were the incidence and median time to facial nerve palsy diagnosis within 30 days of skull base fracture. Secondary outcomes were treatments (corticosteroids, antivirals, facial nerve decompression, botulinum toxin, and facial reanimation), demographics, and rates of hearing loss, vertigo, tympanic membrane rupture, cerebrospinal fluid leak, comorbidities, and loss of consciousness. RESULTS: The 30-day incidence of facial nerve palsy after skull base trauma was 1.0% (738 of 72,273 patients). The median (95% confidence interval [CI]) time to diagnosis was 6 (6-7) days, and only 22.9% were diagnosed within 1 day. There were significantly higher rates (risk difference, 95% CI) of hearing loss (26%, 22-29%), tympanic membrane rupture (6.3%, 4.5-8.1%), cerebrospinal fluid leak (6.4%, 4.5-8.3%), comorbidity (14%, 10.4-17.6%), and loss of consciousness (24.3%, 20.7-27.9%). Loss of consciousness was associated with longer median (95% CI) time to facial nerve palsy diagnosis: 10 (9-10) days. Corticosteroids were the most common treatment but only reported for less than one-third of patients. Only eight patients underwent facial nerve decompression. CONCLUSIONS: Facial nerve palsy after skull base fracture is associated with higher comorbidity, and the diagnosis is often delayed. Few patients were treated with surgery, and there are inconsistencies in the types and timing of treatments.

Promontory Electrocochleography Recordings to Predict Speech-Perception Performance in Cochlear Implant Recipients.

OBJECTIVE: 1) To determine the relationship of electrocochleography (ECochG) responses measured on the promontory with responses measured at the round window (RW) and various intracochlear sites. 2) To evaluate if promontory ECochG responses correlate with postoperative speech-perception performance using the cochlear implant (CI). STUDY DESIGN: Prospective cohort study. SETTING: Tertiary referral center. PATIENTS AND INTERVENTIONS: Ninety-six adult CI recipients with no cochlear malformations or previous otologic surgery. MAIN OUTCOME MEASURES: Acoustically evoked ECochG responses were measured intraoperatively at both extracochlear and intracochlear locations. ECochG total response (ECochG-TR), a measure of residual cochlear function, was calculated by summing the fast Fourier transformation amplitudes in response to 250-Hz to 2-kHz acoustic stimuli. Speech-perception performance was measured at 3 months. RESULTS: There were strong linear correlations for promontory ECochG-TR with the ECochG-TRs measured at the RW ( r = 0.95), just inside scala tympani ( r = 0.91), and after full insertion ( r = 0.83). For an individual subject, the morphology of the ECochG response was similar in character across all positions; however, the response amplitude increased from promontory to RW (~1.6-fold) to just inside scala tympani (~2.6-fold), with the largest response at full insertion (~13.1-fold). Promontory ECochG-TR independently explained 51.8% of the variability ( r2 ) in consonant-nucleus-consonant at 3 months. CONCLUSIONS: Promontory ECochG recordings are strongly correlated with responses previously recorded at extracochlear and intracochlear sites and explain a substantial portion of the variability in CI performance. These findings are a critical step in supporting translation of transtympanic ECochG into the clinic preoperatively to help predict postoperative CI performance.

Clinical Staging to Estimate the Probability of Severe Postoperative Complications in Patients With Vestibular Schwannoma.

Importance: Vestibular schwannomas have long been treated as a homogeneous entity. Clinical symptoms at presentation may help elucidate the underlaying pathophysiologic characteristics of tumor subtypes. Describing the heterogeneity of these benign tumors may assist in predicting clinical outcomes associated with their treatment. Objective: To create a tumor staging system that incorporates symptoms at presentation and tumor size to predict severe surgical complications. Design, Setting, and Participants: A retrospective cohort of patients at a single-center tertiary referral center from January 1, 1998, to October 13, 2020, was studied. Patients diagnosed with sporadic vestibular schwannoma surgically treated at Washington University in St Louis, Missouri, were included. Main Outcomes and Measures: Severe surgical complications within 30 days of surgery as determined by the Clavien-Dindo classification system. Patients experiencing a complication of grade 3 or above were determined to have a severe complication. Results: Of 185 patients evaluated, 40 (22%) had severe postoperative complications. Twenty of the 40 patients (50%) were women; mean (SD) age was 46 (13) years. Patients with severe complications were more likely to have large tumors (>2.5 cm in largest diameter), vestibular symptoms, and recent hearing loss at presentation. Using conjunctive consolidation, a 4-stage clinical severity staging system that incorporates clinical symptoms and tumor size at presentation was created to predict severe complications. The clinical severity staging system demonstrated an improvement in the ability to discriminate severe complications (C index, 0.754; 95% CI, 0.67-0.84) from a model of tumor size alone (C index, 0.706; 95% CI 0.62-0.79). Conclusions and Relevance: This cohort study found that, among patients with vestibular schwannoma, symptoms present at initial evaluation, in addition to tumor size, served as predictors of severe postoperative complications. A new clinical severity staging system incorporating symptoms at presentation can be helpful for clinicians to identify patients at high risk for severe postoperative complications.

Prevalence, Surgical Management, and Audiologic Impact of Sigmoid Sinus Dehiscence Causing Pulsatile Tinnitus.

OBJECTIVE: To evaluate the prevalence, surgical management, and audiologic impact of pulsatile tinnitus caused by sigmoid sinus dehiscence. STUDY DESIGN AND SETTING: Retrospective chart review at a tertiary care hospital. PATIENTS: Adults with unilateral pulsatile tinnitus attributable to sigmoid sinus dehiscence who underwent resurfacing between January 2010 and January 2020. INTERVENTIONS: Transmastoid sigmoid resurfacing. MAIN OUTCOME MEASURES: Resolution of pulsatile tinnitus; audiologic outcomes; complications; tinnitus etiologies. RESULTS: Nineteen patients (89.4% women) had surgery for suspected sigmoid sinus dehiscence. The mean dehiscence size was 6.1 mm (range, 1-10.7 mm). Eight patients had concurrent sigmoid sinus diverticulum and one patient also had jugular bulb dehiscence. Only two patients (10.5%) had the defect identified by radiology. Low-frequency pure-tone average, measured at frequencies of 250 and 500 Hz, showed a significant median improvement of 8.8 dB following resurfacing (18.8 dB versus 10.0 dB, p = 0.02). The majority of patients had complete resolution of pulsatile tinnitus (16/19, 84.2%). Of those without complete resolution, two patients had partial response and one patient had no improvement. There were no significant complications. Of 41 consecutively tracked patients with a pulsatile tinnitus chief complaint, sigmoid pathology represented 32% of cases. CONCLUSIONS: Sigmoid sinus dehiscence represents a common vascular cause of pulsatile tinnitus that, if properly assessed, may be amenable to surgical intervention. Sigmoid sinus resurfacing is safe, does not require decompression, and may improve low-frequency hearing. Radiographic findings of dehiscence are often overlooked without a high index of clinical suspicion. Its relationship with transverse sinus pathology and idiopathic intracranial hypertension remain unclear.

Outcomes after mini-craniotomy middle fossa approach combined with mastoidectomy for lateral skull base defects.

PURPOSE: Controversy exists regarding the ideal approach for repair of lateral skull base defects. Our goal is to report the outcomes following middle cranial fossa (MCF) mini-craniotomy combined with mastoidectomy for patients with superior semicircular canal dehiscence (SSCD), spontaneous cerebrospinal fluid (CSF) leak, and cholesteatoma. MATERIALS AND METHODS: A retrospective database from chart review was formed consisting of 97 patients who met surgical criteria: SSCD, spontaneous CSF leak, and cholesteatoma. Mini-craniotomy MCF approach (<4 × 2 cm in size) combined with mastoidectomy was performed. All patients were admitted directly to the ICU postoperatively. Multiple factors were assessed, including need for revision surgery, duration of surgery, length of post-operative stay, and hospital readmission. RESULTS: Average surgery time was 110 min with no intraoperative complications. The average length of hospitalization was 2 days with an average ICU stay of 1 day. There were no neurologic complications; however, there were 3 inpatient complications (3%) which included 1 patient (1%) that had wound breakdown and 2 patients (2%) that had severe post-operative vertigo. A total of 8 patients (8%) required revision surgery and these were primarily for SSCD. The 30-day readmission rate was 3%. CONCLUSION: In the current series, all patients that underwent mini-craniotomy MCF surgery combined with mastoidectomy had minimal complications, short surgical time, limited hospital stay, low revision surgery rate and few hospital readmissions. This combined approach offers superior visualization of lateral skull base defects without the morbidity and risk typically associated with traditional, extensive MCF surgery.

Cochlear Implant Outcomes Following Vestibular Schwannoma Resection: Systematic Review.

OBJECTIVE: Hearing loss remains a significant morbidity for patients with vestibular schwannomas (VS). A growing number of reports suggest audibility with cochlear implantation following VS resection; however, there is little consensus on preferred timing and cochlear implant (CI) performance. DATA SOURCES: A systematic literature search of the Ovid Medline, Embase, Scopus, and clinicaltrails.gov databases was performed on 9/7/2018. PRISMA reporting guidelines were followed. STUDY SELECTION: Included studies reported CI outcomes in an ear that underwent a VS resection. Untreated VSs, radiated VSs, and CIs in the contralateral ear were excluded. DATA EXTRACTION: Primary outcomes were daily CI use and attainment of open-set speech. Baseline tumor and patient characteristics were recorded. Subjects were divided into two groups: simultaneous CI placement with VS resection (Group 1) versus delayed CI placement after VS resection (Group 2). DATA SYNTHESIS: Twenty-nine articles with 93 patients met inclusion criteria. Most studies were poor quality due to their small, retrospective design. Group 1 had 46 patients, of whom 80.4% used their CI on a daily basis and 50.0% achieved open-set speech. Group 2 had 47 patients, of whom 87.2% used their CI on a daily basis and 59.6% achieved open-set speech. Group 2 had more NF2 patients and larger tumors. CI timing did not significantly impact outcomes. CONCLUSIONS: Audibility with CI after VS resection is feasible. Timing of CI placement (simultaneous versus delayed) did not significantly affect performance. Overall, 83.9% used their CI on a daily basis and 54.8% achieved open-set speech.

Hearing and Quality-of-Life Outcomes After Cochlear Implantation in Adult Hearing Aid Users 65 Years or Older: A Secondary Analysis of a Nonrandomized Clinical Trial.

Importance: Hearing loss, especially moderate to severe forms, has the potential to negatively affect an individual's physical, social, emotional, and cognitive well-being. Moreover, having ineffective binaural hearing increases difficulty understanding speech in noise and leads to a greater degree of social isolation and loneliness and a reduced quality of life (QoL). Objective: To explore the audiometric and holistic effects of cochlear implantation in a group of adults 65 years or older compared with an optimized bilateral hearing aid condition. Design, Setting, and Participants: This ad hoc secondary analysis of a prospective, single-subject, repeated-measures nonrandomized clinical trial included 13 cochlear implantation centers across the United States. Participants 65 years or older with postlingual bilateral moderate-to-profound sensorineural hearing loss with aided Consonant-Vowel Nucleus-Consonant (CNC) word scores in quiet of 40% or less in the ear to undergo implantation and 50% or less in the contralateral ear were included in the analysis. Baseline QoL testing was performed after 1 month of optimized bilateral hearing aid use. Participants were enrolled from February 20, 2017, to May 3, 2018, and follow-up was completed December 21, 2018. Data were analyzed from March 25, 2019, to March 31, 2020. Interventions: Unilateral implantation with a slim, modiolar cochlear implant device. Hearing aid use in the contralateral ear was required through the 6-month primary end-point interval. Main Outcomes and Measures: The primary objective was to evaluate speech perception before and 6 months after activation of a new cochlear implant. Secondary objectives were QoL metrics in the everyday listening condition before and 6 months after implantation. Results: Seventy participants (51 men [73%]) with a median age of 74 (range, 65-91) years were included in the analysis. No major adverse events occurred. Mixed-model analysis with estimated marginal means and 95% CIs compared preimplantation baseline performance with 6-month postimplantation performance. A clinically important improvement in CNC words was shown in the bimodal condition, with a mean difference of 37.2% (95% CI, 32.0%-42.4%), and in the unilateral (cochlear implant only) condition, with a mean difference of 44.1% (95% CI, 39.0%-49.2%). A clinically important improvement in noise (AzBio sentences signal-to-noise ratio of +10 dB) was also shown, with a mean difference of 21.6% (95% CI, 15.7%-27.5%) in the bimodal condition and 24.5% (95% CI, 18.3%-30.7%) in the unilateral condition. The Health Utilities Index Mark 3 multiple-attribute score improved by 0.186 (95% CI, 0.136-0.234); the Speech, Spatial, and Qualities of Hearing Scale total score improved by 2.58 (95% CI, 2.18-2.99); and a novel Device Use Questionnaire reported 94% of participants were satisfied with overall hearing in the everyday listening condition. Conclusions and Relevance: This subgroup analysis of patients 65 years or older enrolled in a within-subject clinical trial of cochlear implantation demonstrated clinically meaningful audiometric and QoL benefit with an acceptable risk profile. These findings suggest that cochlear implantation in older adults may facilitate the concept of healthy aging. Trial Registration: ClinicalTrials.gov Identifier: NCT03007472.

Assessment of Speech Understanding After Cochlear Implantation in Adult Hearing Aid Users: A Nonrandomized Controlled Trial.

Importance: Cochlear implants were approved for use in adults in the 1980s, but use remains low owing to a lack of awareness regarding cochlear implantation candidacy criteria and expected outcomes. There have been limited, small series examining the safety and effectiveness of cochlear implantation in adult hearing aid (HA) users with and without mild cognitive impairment (MCI). Objective: To investigate the safety and effectiveness of a single-ear cochlear implant in a group of optimized adult HA users with and without MCI across a variety of domains. Design, Setting, and Participants: In this nonrandomized controlled trial, a multicenter, prospective, repeated-measures investigation was conducted at 13 US institutions. The setting was academic and community-based cochlear implant programs. Eligible participants were 100 adults (aged >18 years) with postlinguistic onset of bilateral moderate sloping to profound or worse sensorineural hearing loss (≤20 years' duration). Fluent English speakers underwent an optimized bilateral HA trial for at least 30 days. Individuals with aided Consonant-Vowel Nucleus-Consonant (CNC) word score in quiet of 40% or less correct in the ear to be implanted and 50% or less correct in the contralateral ear were offered cochlear implants. The first participant was enrolled on February 20, 2017, and the last participant was enrolled on May 3, 2018. The final follow-up was on December 21, 2018. Interventions: Participants received the same cochlear implant system and contralateral HA. Main Outcomes and Measures: The primary outcome measure was speech understanding in quiet (CNC word score) using both the cochlear implant and opposite ear HA. Secondary outcome measures included the following: adverse events; speech understanding in noise (AzBio signal-to-noise ratio of +10 db [+10 SNR]) Health Utilities Index Mark 3 (HUI3); Speech, Spatial, and Qualities of Hearing Questionnaire 49 (SSQ49); and Montreal Cognitive Assessment (MoCA). Results: The median age at cochlear implantation of the 96 patients included in the trial was 71 years (range, 23-91 years), and 62 patients (65%) were male. Three serious adverse events requiring revision surgery occurred, and all resolved without sequelae. By 6 months after activation, the absolute marginal mean change in CNC word score and AzBio +10 SNR was 40.5% (95% CI, 35.9%-45.0%) and 24.1% (95% CI, 18.9%-29.4%), respectively. Ninety-one percent (87 of 96) of participants had a clinically important improvement (>15%) in the CNC word score in the implant ear. Mild cognitive impairment (MoCA total score ≤25) was observed in 48 of 81 study participants (59%) at baseline. Speech perception marginal mean improvements were similar between individuals with and without baseline MCI, with values of 40.9% (95% CI, 35.2%-46.6%) and 39.6% (95% CI, 31.8%-47.4%), respectively, for CNC word score and 27.5% (95% CI, 21.0%-33.9%) and 17.8% (95% CI, 9.0%-26.6%), respectively, for AzBio +10 SNR. Statistically significant and clinically important improvements in the HUI3 and SSQ49 were evident at 6 months. Conclusions and Relevance: The findings of this nonrandomized controlled trial seem to indicate that cochlear implants are safe and effective in restoring speech understanding in both quiet and noise and improve quality of life in individuals with and without MCI. Trial Registration: ClinicalTrials.gov Identifier: NCT03007472.

Immediate and 1-Year Outcomes with a Slim Modiolar Cochlear Implant Electrode Array.

OBJECTIVE: To explore the immediate and 1-year outcomes of patients who underwent implantation with the slim modiolar electrode (SME). STUDY DESIGN: Consecutive case series with chart review. SETTING: Tertiary referral academic center. SUBJECT AND METHODS: Between May 2016 and August 2018, a total of 326 cochlear implantations (CIs) were performed. Intraoperative x-rays were performed in all cases to identify tip rollovers. Scalar location was identified for 76 CIs that had postoperative computed tomography reconstructions. Speech outcomes were measured at 3, 6, and 12 months with consonant-nucleus-consonant word and AzBio sentences in quiet and noise (+10-dB signal-to-noise ratio). Preservation of hearing was defined as maintaining a low-frequency pure tone average ≤80 dB at 250 and 500 Hz. RESULTS: Among 326 CIs, 23 (7%) had tip rollovers. Postoperative reconstructions revealed 5 of 76 (6.6%) scalar translocations. A subset of 177 cases met criteria for evaluation of speech perception scores. The marginal mean differences between presurgery and 12 months for speech tests were as follows: consonant-nucleus-consonant, 43.7 (95% CI, 39.8-47.6); AzBio in quiet, 49.7 (95% CI, 44.9-54.4); and AzBio in noise, 29.9 (95% CI, 25.2-34.7). Sixty-one patients were identified with preservable hearing (low-frequency pure tone average ≤80 dB), and 12 of 61 (20%) preserved hearing at 1 year. CONCLUSION: CI with SME provides reliable scala tympani insertion in a consistent perimodiolar position. An initially increased tip rollover rate improved with case volume and sheath design improvement. For long-term outcomes, speech performance was comparable to that of other cochlear implants. While hearing preservation for the SME may be better than prior perimodiolar electrodes, consistent outcomes are unlikely.

Development of a Mixed Reality Platform for Lateral Skull Base Anatomy.

OBJECTIVES: A mixed reality (MR) headset that enables three-dimensional (3D) visualization of interactive holograms anchored to specific points in physical space was developed for use with lateral skull base anatomy. The objectives of this study are to: 1) develop an augmented reality platform using the headset for visualization of temporal bone structures, and 2) measure the accuracy of the platform as an image guidance system. METHODS: A combination of semiautomatic and manual segmentation was used to generate 3D reconstructions of soft tissue and bony anatomy of cadaver heads and temporal bones from 2D computed tomography images. A Mixed-Reality platform was developed using C# programming to generate interactive 3D holograms that could be displayed in the HoloLens headset. Accuracy of visual surface registration was determined by target registration error between seven predefined points on a 3D holographic skull and 3D printed model. RESULTS: Interactive 3D holograms of soft tissue, bony anatomy, and internal ear structures of cadaveric models were generated and visualized in the MR headset. Software user interface was developed to allow for user control of the virtual images through gaze, voice, and gesture commands. Visual surface point matching registration was used to align and anchor holograms to physical objects. The average target registration error of our system was 5.76 mm ±â€Š0.54. CONCLUSION: In this article, we demonstrate that an MR headset can be applied to display interactive 3D anatomic structures of the temporal bone that can be overlaid on physical models. This technology has the potential to be used as an image guidance tool during anatomic dissection and lateral skull base surgery.

Complications and 30-day hospital readmission rates of patients undergoing tracheostomy: A prospective analysis.

OBJECTIVE: To determine inpatient and outpatient tracheostomy complication rates and 30-day hospital readmission rates, and to assess patient and procedural risk factors associated with complications and readmissions. STUDY DESIGN: Prospective cohort study. METHODS: Adult patients undergoing tracheostomy at a single academic hospital performed by any service, for any indication, were enrolled in this study over the course of 1 year. All patients had complete 30-day follow-up after discharge to determine complication and hospital readmission rates. Logistic regression was used to assess patient and procedural risk factors associated with these events. RESULTS: One hundred patients were enrolled in this study from June 1, 2015, to June 1, 2016. The overall inpatient tracheostomy complication rate was 47% (95% confidence interval [CI], 37%-57%). Inpatient complications were associated with location in the medical intensive care unit and increased length of hospitalization. The outpatient tracheostomy complication rate was 15% (95% CI, 8%-22%). Outpatient complications were associated with having a previous tracheostomy or an awake tracheostomy under local anesthesia. The all-cause 30-day hospital readmission rate was 33% (95% CI, 24%-42%), and the tracheostomy-specific readmission rate was 13% (95% CI, 6%-20%). All-cause readmissions were associated with diabetes, length of hospitalization after tracheostomy, and outpatient complications. The overall mortality rate during the study period was 11% (95% CI, 5%-17%), with one tracheostomy-related death. CONCLUSION: Patients undergoing tracheostomies are at high risk for both inpatient and outpatient complications, as well for 30-day hospital readmission. Understanding patient and procedural risk factors associated with these events will help guide interventions for quality improvement. LEVEL OF EVIDENCE: 2b. Laryngoscope, 127:2746-2753, 2017.