[AUDITORY OUTCOMES OF COCHLEAR IMPLANTATION IN MENIERE'S DISEASE].

BACKGROUND: Cochlear implants are valuable in the auditory rehabilitation of patients with severe to profound hearing loss. However, there is limited data on the outcomes of cochlear implantation in patients with Meniere's disease (MD). OBJECTIVES: In this study, we aim to evaluate the auditory outcomes of cochlear implantation in patients with MD. METHODS: A retrospective case series of patients with MD and severe to profound sensorineural hearing loss (SNHL), who underwent cochlear implantation at a tertiary academic center between 2006-2017. Patient's clinical characteristics and audiometric data were reviewed. RESULTS: The study included 20 ears in 19 patients with MD who underwent cochlear implantation with available pre- and postoperative audiometric data. There were 10 males and 9 females with a mean age of 63 years and a mean follow-up duration of 70.8 months. Pre- and post-implant CNC word recognition scores were 18.31% and 66.89%, respectively (p<0.001). Pre- and post-implant AzBio and/or HINT sentence recognition scores were 12.25% and 68.28% in quiet, respectively (p<0.001), and 18.25% and 63.43% in noise, respectively (p<0.001). CONCLUSIONS: Cochlear implantation resulted in an improvement of word and sentence recognition scores in MD patients. These results support the role of cochlear implants in the auditory rehabilitation of MD. DISCUSSION: Dr. Samy received research support from Cochlear Corporation.

Cochlear Fibrosis after Vestibular Schwannoma Resection via the Middle Cranial Fossa Approach.

OBJECTIVE: The aim of this study was to determine the incidence of cochlear fibrosis after vestibular schwannoma (VS) resection via middle cranial fossa (MCF) approach. DESIGN: A retrospective case review was conducted. SETTING: The review was conducted in a tertiary care academic medical center. PARTICIPANTS: Patients who (1) underwent resection of VS via MCF approach between 2013 and 2018, (2) had complete pre- and post-audiometric testing, and (3) had clinical follow-up with magnetic resonance imaging (MRI) for at least 1 year after surgery were included. MAIN OUTCOME MEASURE(S): The main outcome of this study was cochlear fibrosis as assessed by MRI 1 year after surgery. RESULTS: Fifty-one patients underwent VS resection via MCF technique during the study period. Of 31 patients with AAO-HNS class A or B preoperative hearing ability, 18 (58.0%) maintained class A, B, or C hearing postoperatively. Of 16 patients who lost hearing and had MRI 1 year after surgery, 11 (61.1%) had MRI evidence of fibrosis in at least some portion of the labyrinth and 4 (22.2%) showed evidence of cochlear fibrosis. Of 16 patients with preserved hearing and MRI 1 year after surgery, 4 (25%) had fibrosis in some portion of the labyrinth, with no fibrosis in the cochlea. CONCLUSIONS: In patients who lose hearing during VS resection with the MCF approach, there is usually MRI evidence of fibrosis in the labyrinth 1 year after surgery. However, there is also, but less commonly, fibrosis involving the cochlea. It is unclear if this will affect the ability to insert a cochlear implant electrode array.

Neurofibromatosis Type 2 (NF2) and the Implications for Vestibular Schwannoma and Meningioma Pathogenesis.

Patients diagnosed with neurofibromatosis type 2 (NF2) are extremely likely to develop meningiomas, in addition to vestibular schwannomas. Meningiomas are a common primary brain tumor; many NF2 patients suffer from multiple meningiomas. In NF2, patients have mutations in the NF2 gene, specifically with loss of function in a tumor-suppressor protein that has a number of synonymous names, including: Merlin, Neurofibromin 2, and schwannomin. Merlin is a 70 kDa protein that has 10 different isoforms. The Hippo Tumor Suppressor pathway is regulated upstream by Merlin. This pathway is critical in regulating cell proliferation and apoptosis, characteristics that are important for tumor progression. Mutations of the NF2 gene are strongly associated with NF2 diagnosis, leading to benign proliferative conditions such as vestibular schwannomas and meningiomas. Unfortunately, even though these tumors are benign, they are associated with significant morbidity and the potential for early mortality. In this review, we aim to encompass meningiomas and vestibular schwannomas as they pertain to NF2 by assessing molecular genetics, common tumor types, and tumor pathogenesis.

Cortical Processing of Frequency Changes Reflected by the Acoustic Change Complex in Adult Cochlear Implant Users.

The purpose of this study was to examine neural substrates of frequency change detection in cochlear implant (CI) recipients using the acoustic change complex (ACC), a type of cortical auditory evoked potential elicited by acoustic changes in an ongoing stimulus. A psychoacoustic test and electroencephalographic recording were administered in 12 postlingually deafened adult CI users. The stimuli were pure tones containing different magnitudes of upward frequency changes. Results showed that the frequency change detection threshold (FCDT) was 3.79% in the CI users, with a large variability. The ACC N1' latency was significantly correlated with the FCDT and the clinically collected speech perception score. The results suggested that the ACC evoked by frequency changes can serve as a useful objective tool in assessing frequency change detection capability and predicting speech perception performance in CI users.

Intraoperative neurophysiological monitoring team's communiqué with anesthesia professionals.

BACKGROUND AND AIMS: Intraoperative neurophysiological monitoring (IONM) is the standard of care during many spinal, vascular, and intracranial surgeries. High-quality perioperative care requires the communication and cooperation of several multidisciplinary teams. One of these multidisciplinary services is intraoperative neuromonitoring (IONM), while other teams represent anesthesia and surgery. Few studies have investigated the IONM team's objective communication with anesthesia providers. We conducted a retrospective review of IONM-related quality assurance data to identify how changes in the evoked potentials observed during the surgery were communicated within our IONM-anesthesia team and determined the resulting qualitative outcomes. MATERIAL AND METHODS: Quality assurance records of 3,112 patients who underwent surgical procedures with IONM (from 2010 to 2015) were reviewed. We examined communications regarding perioperative evoked potential or electroencephalography (EEG) fluctuations that prompted neurophysiologists to alert/notify the anesthesia team to consider alteration of anesthetic depth/drug regimen or patient positioning and analyzed the outcomes of these interventions. RESULTS: Of the total of 1280 (41.13%) communications issued, there were 347 notifications and 11 alerts made by the neurophysiologist to the anesthesia team for various types of neuro/orthopedic surgeries. Prompt communication led to resolution of 90% of alerts and 80% of notifications after corrective measures were executed by the anesthesiologists. Notifications mainly related to limb malpositioning and extravasation of intravenous fluid. CONCLUSION: Based on our institutions' protocol and algorithm for intervention during IONM-supported surgeries, our findings of resolution in alerts and notifications indicate that successful communications between the two teams could potentially lead to improved anesthetic care and patient safety.

Contemporary Neuroradiographic Assessment of the Cochleo-Carotid Partition.

PURPOSE: The cochleo-carotid partition (CCP) describes the intimate anatomic relationship between the petrous carotid artery and the cochlear basal turn. This partition bears significant surgical and unique clinical relevance. The purpose of this paper is to radiographically assess the CCP and discuss its clinical implications. METHODS: A total of 155 consecutive fine-cut temporal bone CT scans were retrospectively reviewed, and study scans were digitally analyzed in both axial and coronal views. The shortest distance between the petrous carotid canal and the cochlear basal turn was measured. RESULTS: In all, 310 temporal bones were studied, with a mean CCP of 1.9 mm (range 0.2-8.5, SD 1.1). The following CCP measurements were obtained: ≤1.0 mm [n = 46 (14.8%)]; 1.1-2.0 mm [n = 161 (51.9%)]; 2.1-3.0 mm [n = 29 (9.4%)], and ≥4.0 mm [n = 12 (4.2%)]. One temporal bone (0.3%) had complete CCP dehiscence. There was a positive correlation between each patient's right and left CCP measures (p < 0.005) and a significant negative correlation between CCP grade and age (p = 0.027). CONCLUSIONS: The CCP is a narrow anatomic confinement measuring ≤2 mm in 66.7% of patients. Potential implications of the CCP include iatrogenic risks, its possible function as a third inner ear window in patients with audiovestibular symptoms, and pathophysiology of new-onset tinnitus following cochlear implantation.

Radiographic Assessment and Surgical Implications of Arcuate Eminence Pneumatization.

BACKGROUND: The middle cranial fossa (MCF) approach is a valuable yet technically challenging technique. Identification of the superior semicircular canal (SCC) using the arcuate eminence (AE) was proposed as a surface landmark. However, the AE is sometimes absent, with inconsistent relationship to the SCC. Air cells in the AE area facilitate safer identification of the SCC. The aim of this study is to determine the radiographic prevalence of AE pneumatization. METHODS: Two hundred consecutive fine-cut temporal bone CT scans were retrospectively reviewed. The region of the petrosal bone at and above the level of the SCC dome was assessed for the presence of air cells, and graded 0 (no pneumatization) to 2 (well pneumatized). RESULTS: Four hundred temporal bones were studied. The average age was 49 years (range 18-89). Of all AE assessments, 47 (12%) were nonpneumatized, 62 (15%) partially pneumatized, and 291 (73%) well pneumatized. There was no significant correlation between patient age and pneumatization grade (p = 0.72). CONCLUSION: The SCC is a valuable landmark in MCF surgery as it holds consistent relationships to adjacent critical structures. Surrounding air cells should facilitate safer initial identification of the SCC, as the AE region is well pneumatized in 73% of patients.

Temporal bone fracture related facial palsy: efficacy of decompression with and without grafting.

PURPOSE OF REVIEW: This systematic review investigates the recent literature and aims to determine the approach, efficacy, and timing of facial nerve decompression with or without grafting in temporal bone fractures with facial palsy. RECENT FINDINGS: The surgical management of facial palsy is reserved for a small population of cases in which electrophysiologic tests indicate a poor likelihood of spontaneous recovery. The transmastoid (TM), middle cranial fossa (MCF), and translabyrinthine (TL) approaches to the facial nerve provide access to the entire intracranial and intratemporal segments of the facial nerve. In temporal bone (TB) related facial palsy, the peri-geniculate and labyrinthine portions of the facial nerve are most commonly affected by either direct trauma and/or subsequent edema. When hearing is still serviceable, the combined TM/MCF approach provides the best access to these regions. In the presence of severe sensorineural hearing loss (SNHL), the TL approach is the most appropriate for total facial nerve exploration (this can be done in conjunction with simultaneous cochlear implantation if the cochlear nerve has not been avulsed). Grade I to III House-Brackmann (HB) results can be anticipated in timely decompression of facial nerve injury caused by edema or intraneuronal hemorrhage. Grade III outcomes, with slight weakness and synkinesis, is the outcome to be expected from the use of interpositional grafts or primary neurorrhaphy. In addition to good eye care and the use of systemic steroids (if not contraindicated in the acute trauma setting), surgical decompression with or without grafting/neurorrhaphy may be offered to patients with appropriate electrophysiologic testing, physical examination findings, and radiologic localization of injury. SUMMARY: Surgery of the facial nerve remains an option for select patients. Here, we discuss the indications and results of treatment as well as the best surgical approach to facial nerve determined based on patient's hearing status and radiologic data. Controversy remains about whether timing of surgery (e.g., immediate vs. delayed intervention) impacts outcomes. However, no one with facial palsy due to a temporal bone fracture should be left with a complete facial paralysis.

Outcomes of Soft Versus Bony Canal Wall Reconstruction with Mastoid Obliteration.

OBJECTIVE: To compare recidivism rates, audiometric outcomes, and postoperative complication rates between soft-wall canal wall reconstruction (S-CWR) versus bony-wall CWR (B-CWR) with mastoid obliteration (MO) in patients with cholesteatoma. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary neurotologic referral center. PATIENTS: Ninety patients aged ≥18 years old who underwent CWR with MO, either S-CWR or B-CWR, for cholesteatoma with one surgeon from January 2011 to January 2022. Patients were followed postoperatively for at least 12 months with or without second-look ossiculoplasty. INTERVENTIONS: Tympanomastoidectomy with CWR (soft vs. bony material) and mastoid obliteration. MAIN OUTCOME MEASURES: Recidivism rates; conversion rate to CWD; pre- versus postoperative pure tone averages, speech reception thresholds, word recognition scores, and air-bone gaps; postoperative complication rates. RESULTS: Middle ear and mastoid cholesteatoma recidivism rates were not significantly different between B-CWR (17.3%) and S-CWR (18.4%, p = 0.71). There was no significant difference in pre- versus postoperative change in ABG (B-CWR, -2.1 dB; S-CWR, +1.6 dB; p = 0.91) nor in the proportion of postoperative ABGs <20 dB (B-CWR, 41.3%; S-CWR, 30.7%; p = 0.42) between B-CWR and S-CWR. Further, there were no significant differences in complication rates between B-CWR and S-CWR other than increased minor TM perforations/retractions in B-CWR (63% vs. 40%, p = 0.03). CONCLUSIONS: Analysis of recidivism rates, audiometric outcomes and postoperative complications between B-CWR with MO versus S-CWR with MO revealed no significant difference. Both approaches are as effective in eradicating cholesteatoma while preserving relatively normal EAC anatomy and hearing. Surgeon preference and technical skill level may guide the surgeon's choice in approach.

Comparing in-clinic versus telehealth for vestibular physical therapy.

BACKGROUND: Vestibular rehabilitation (VR) is a commonly employed treatment method for disorders of dizziness and imbalance. Access to a clinic for rehabilitation appointments can be challenging for a person experiencing dizziness. Telehealth may offer a comparable alternative to clinic-based VR for some patients. OBJECTIVE: The objective of this study was to determine the efficacy of telehealth-based VR compared to traditional clinic-based VR, as measured with the Dizziness Handicapped Inventory (DHI) in a retrospective sample of patients with vestibular conditions. METHODS: This is a retrospective, multi-institutional review from May 2020 to January 2021. Three study groups were analyzed: a telehealth group, a hybrid group, and a clinic based control group. Treatment efficacy was measured using the DHI. A repeated measures ANCOVA was performed to compare changes between the groups and across timepoints. RESULTS: The repeated measures ANCOVA was not significant for the interaction of groups (control, telehealth, and hybrid) by time (pre and post) (p > 0.05). However, there was a significant main effect for time (pre and post) (p < 0.05). Specifically, all groups improved DHI scores from pre to post treatment with mean differences of control: 31.85 points, telehealth: 18.75 points, and hybrid: 21.45 points. CONCLUSION: Findings showed that in-clinic, telehealth, and hybrid groups demonstrated a decrease in DHI scores, indicating self-reported improvements in the impact of dizziness on daily life. Continued research is recommended to explore the efficacy of using telehealth in assessing and treating vestibular conditions.

The Effectiveness of Facial Neuromuscular Retraining on Patients with Facial Nerve Dysfunction: A Mental Health and Quality of Life Analysis.

Background: Facial muscle dysfunction can have drastic psychosocial effects. Objectives: To evaluate the impacts of customized neuromuscular retraining on mental health, quality of life (QoL), facial muscle function, and synkinesis. Methods: Thirty patients with facial nerve dysfunction completed a course of neuromuscular retraining. Patients' mental health, QoL, facial muscle function, and synkinesis were evaluated using Patient Health Questionnaire (PHQ-9), Facial Clinimetric Evaluation (FaCE) scale, electronic, clinician-graded facial function scale (eFACE), and Synkinesis Assessment Questionnaire (SAQ) at the initial and final visits. Scores were compared before and after treatment. Results: Patients (n = 30) included had a mean age of 59.4 ± 13.4 years (range 32.3-82.8) and were mostly female (22/30, 73.3%). The most common etiology was Iatrogenic facial nerve paralysis (11/20, 36.7%). Most patients had postfacial paralysis synkinesis (15/30, 50%), while 10 had complete flaccid paralysis. The median house-Brackmann score was 2 (range 1-6). The mean duration of facial palsy was 39.5 ± 106.9 (range 1-576 months). The duration of follow-up after the initial treatment session was 5.5 months, including 10 sessions. After neuromuscular retraining median PHQ-9 scores improved from 5 (range 0-25) to 3 (range 0-20) (p = 0.002). Mean FaCE PROM scores increased from 47.7 ± 11.5 to 56.5 ± 8.8 (p = 0.001). The mean eFACE score increased from 55.8 ± 15.1 to 71.7 ± 13.6 (p < 0.001). Median SAQ score was lower at the final visit (34.6 ± 13.4) compared to the initial visit (47.7 ± 17.8; p < 0.001). Conclusion: Customized neuromuscular retraining may improve patient-reported mental health, QoL, and facial muscle function and reduce synkinesis in facial nerve dysfunction.

Anatomical Study of the Supratentorial Extension for the Retrolabyrinthine Presigmoid Approaches.

BACKGROUND: Supratentorial craniotomy represents the upper part of the combined trans-tentorial or the supra-infratentorial presigmoid approach. In this study, we provide qualitative and quantitative analyses for the supratentorial extension of the presigmoid retrolabyrinthine suprameatal approach (PRSA). METHODS: The infratentorial PRSA followed by the supratentorial extension craniotomy with dividing and removal of the tentorial strip were performed on both sides of 5 injected human cadaver heads (n = 10 sides). Quantitative analysis was performed for the surface area gained (surgical accessibility) by adding the supratentorial craniotomy. Qualitative analysis was performed for the parts of the brainstem, cranial nerves, and vascular structures that became accessible by adding the supratentorial craniotomy. The anatomical obstacles encountered in the added operative corridor were analyzed. RESULTS: The supratentorial extension of PRSA provides an increase in surgical accessibility of 102.65% as compared to the PRSA standalone. The mean surface area of the exposed brainstem is 197.98 (standard deviation: 76.222) and 401.209 (standard deviation: 123.96) for the infratentorial and the combined supra-infratentorial presigmoid approach, respectively. Exposure for parts of III, IV, and V cranial nerves is added after the extension, and the surface area of the outer craniotomy defect has increased by 60.32%. Parts of the basilar, anterior inferior cerebellar, and superior cerebellar arteries are accessible after the supratentorial extension. CONCLUSIONS: The supratentorial extension of PRSA allows access to the supra-trigeminal area of the pons and the lower part of the midbrain. Considering this surgical accessibility and exposure significantly assists in planning such complex approaches while targeting central skull base lesions.

Petrous Carotid Artery Thrombosis in an Immunocompromised Patient Presenting With Mastoiditis, A Case Report.

OBJECTIVES: The neurotologic literature commonly describes venous sinus thrombosis as a complication of mastoiditis. However, thrombosis of the internal carotid artery in the setting of mastoiditis is rarely described. We aim to document a case of carotid artery thrombosis in a patient presenting with mastoiditis. METHODS: We describe this case and review relevant literature. RESULTS: A renal transplant patient was transferred to our hospital with a left middle cerebral artery (MCA) infarct due to acute mastoiditis. Examination demonstrated middle ear effusion and radiologic workup confirmed mastoid infection adjacent to the site of arterial thrombosis. During cortical mastoidectomy and facial recess approach to the middle ear, the petrous carotid bone was found to be dehiscent with pneumatization of the petrous apex. Thrombosis was found to resolve following surgery, IV antibiotics and anticoagulation. Clinically, his focal neurological deficits improved. Proximity of the infectious process to an exposed petrous carotid artery supports the hypothesis that this patient's thrombus was a product of infectious spread and extra-luminal compression. CONCLUSION: To our knowledge, this is the first report of MCA infarction due to petrous ICA arterial thrombus in the setting of mastoid infection. The patient's immunocompromised state may have predisposed and contributed to the adverse outcome. We advocate for aggressive management of acute mastoiditis in the immunocompromised to prevent or manage complications (such as venous thrombophlebitis as well as ICA thrombus) as these patients don't show typical signs of infection and inflammation.

Quantification of Fat Graft Retention in the Translabyrinthine Approach Using Magnetic Resonance Imaging Volumetric Analysis.

OBJECTIVE: To characterize the viability and volume of autologous free fat grafts over time, determine clinical/patient factors that may affect free fat graft survival and assess the clinical impact of free fat graft survival on patient outcomes in the translabyrinthine approach for lateral skull base tumor resection. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary neurotologic referral center. PATIENTS: Forty-two adult patients who underwent translabyrinthine craniotomy for resection of a lateral skull base tumor with the mastoid defect filled by autologous abdominal fat graft and subsequently underwent more than one postoperative magnetic resonance imaging (MRI) scans of the brain. INTERVENTIONS: Mastoid obliteration with abdominal fat after craniotomy, postoperative MRI. MAIN OUTCOME MEASURES: Rate of fat graft volume loss, fraction retention of original fat graft volume, initial fat graft volume, time to steady-state fat graft retention, rate of postoperative cerebrospinal fluid (CSF) leak, and/or pseudomeningocele formation. RESULTS: Patients were followed postoperatively with MRI for a mean of 31.6 months with a mean of 3.2 postoperative MRIs per patient. Initial graft size was a mean of 18.7 cm3 with a steady-state fat graft retention of 35.5%. Steady-state graft retention (<5% loss per year) was achieved at a mean of 24.96 months postoperatively. No significant association was found in multivariate regression analysis of clinical factors impact on fat graft retention and CSF leak/pseudomeningocele formation. CONCLUSIONS: In the use of autologous abdominal free fat graft for filling mastoid defects after translabyrinthine craniotomy, there is a logarithmic decline in fat graft volume over time, reaching steady state in 2 years. Rates of CSF leak or pseudomeningocele formation were not significantly affected by initial volume of the fat graft, rate of fat graft resorption, nor the fraction of original fat graft volume at steady state. In addition, no analyzed clinical factors significantly influenced fat graft retention over time.

Surgical Closure of the Eustachian Tube Through Middle Fossa and Transmastoid Approaches: A Pilot Cadaveric Anatomy Study.

BACKGROUND: Cerebrospinal fluid rhinorrhea after temporal bone surgery involves drainage from the Eustachian tube (ET) into the nasopharynx, causing significant patient morbidity. Variable anatomy of the ET accounts for failures of currently used ET obliteration techniques. OBJECTIVE: To describe the surgical anatomy of the ET and examine possible techniques for ET closure through middle fossa (MF) and transmastoid approaches. METHODS: We described the surgical anatomy of the ET from the MF and transmastoid approaches in 5 adult cadaveric heads, measuring morphometric and surgical anatomy parameters and establishing targets for definite ET obliteration. RESULTS: The osseous ET measured an average of 19.53 mm (±1.56 mm), with a mean diameter of 2.24 mm (±0.29 mm). The shortest distance between the greater superficial petrosal nerve and the ET junction was 6.61 mm (±0.61 mm). Shortest distances between the ET junction and the foramen spinosum and posterior border of the foramen ovale were 1.09 mm (±0.24 mm) and 2.03 mm (±0.30 mm), respectively. Closure of the cartilaginous ET may be performed by folding it in on itself, securing it by packing, suturing, or surgical clip ligation. CONCLUSION: Definite obliteration of the cartilaginous ET appears feasible and the most definite approach to eliminate egress of cerebrospinal fluid to the nasopharynx using the MF approach. This technique may be used as an adjunct to skull base procedures where ET closure is planned.

Transcanal Transpromontorial Approaches to the Internal Auditory Canal: A Systematic Review.

OBJECTIVE: Exclusive endoscopic (EETTA) and expanded (ExpTTA) transcanal transpromontorial approaches have shown promising results for treating internal auditory canal (IAC) lesions. We reviewed the literature to answer the question: "Do EETTA and ExpTTA achieve high rates of complete resection and low rates of complications in treating patients with IAC pathologies?" DATA SOURCES: PubMed, EMBASE, Scopus, Web of Science, and Cochrane were searched. REVIEW METHODS: Studies reporting EETTA/ExpTTA for IAC pathologies were included. Indications and techniques were discussed and meta-analyzed rates of outcomes and complications were obtained with random-effect model meta-analyses. RESULTS: We included 16 studies comprising 173 patients, all with non-serviceable hearing. Baseline FN function was mostly House-Brackmann-I (96.5%; 95% CI: 94.9-98.1%). Most lesions were vestibular/cochlear schwannomas (98.3%; 95% CI: 96.7-99.8%) of Koos-I (45.9%; 95% CI: 41.3-50.3%) or II (47.1%; 95% CI: 43-51.1%). EETTA was performed in 101 patients (58.4%; 95% CI: 52.4-64.3%) and ExpTTA in 72 (41.6%; 95% CI: 35.6-47.6%), achieving gross-total resection in all cases. Transient complications occurred in 30 patients (17.3%; 95% CI: 13.9-20.5%), with meta-analyzed rates of 9% (95% CI: 4-15%), comprising FN palsy with spontaneous resolution (10.4%; 95% CI: 7.7-13.1%). Persistent complications occurred in 34 patients (19.6%; 95% CI: 17.1-22.2%), with meta-analyzed rates of 12% (95% CI: 7-19%), comprising persistent FN palsy in 22 patients (12.7%; 95% CI: 10.2-15.2%). Mean follow-up was 16 months (range, 1-69; 95% CI: 14.7-17.4). Post-surgery FN function was stable in 131 patients (75.8%; 95% CI: 72.1-79.5%), worsened in 38 (21.9%; 95% CI: 18.8-25%), and improved in 4 (2.3%; 95% CI: 0.7-3.9%), with meta-analyzed rates of improved/stable response of 84% (95% CI: 76-90%). CONCLUSION: Transpromontorial approaches offer newer routes for IAC surgery, but their restricted indications and unfavorable FN outcomes currently limit their use. Laryngoscope, 133:2856-2867, 2023.

A proposed classification system for presigmoid approaches: a scoping review.

OBJECTIVE: The "presigmoid corridor" covers a spectrum of approaches using the petrous temporal bone either as a target in treating intracanalicular lesions or as a route to access the internal auditory canal (IAC), jugular foramen, or brainstem. Complex presigmoid approaches have been continuously developed and refined over the years, leading to great heterogeneity in their definitions and descriptions. Owing to the common use of the presigmoid corridor in lateral skull base surgery, a simple anatomy-based and self-explanatory classification is needed to delineate the operative perspective of the different variants of the presigmoid route. Herein, the authors conducted a scoping review of the literature with the aim of proposing a classification system for presigmoid approaches. METHODS: The PubMed, EMBASE, Scopus, and Web of Science databases were searched from inception to December 9, 2022, following the PRISMA Extension for Scoping Reviews guidelines to include clinical studies reporting the use of "stand-alone" presigmoid approaches. Findings were summarized based on the anatomical corridor, trajectory, and target lesions to classify the different variants of the presigmoid approach. RESULTS: Ninety-nine clinical studies were included for analysis, and the most common target lesions were vestibular schwannomas (60/99, 60.6%) and petroclival meningiomas (12/99, 12.1%). All approaches had a common entry pathway (i.e., mastoidectomy) but were differentiated into two main categories based on their relationship to the labyrinth: translabyrinthine or anterior corridor (80/99, 80.8%) and retrolabyrinthine or posterior corridor (20/99, 20.2%). The anterior corridor comprised 5 variations based on the extent of bone resection: 1) partial translabyrinthine (5/99, 5.1%), 2) transcrusal (2/99, 2.0%), 3) translabyrinthine proper (61/99, 61.6%), 4) transotic (5/99, 5.1%), and 5) transcochlear (17/99, 17.2%). The posterior corridor consisted of 4 variations based on the target area and trajectory in relation to the IAC: 6) retrolabyrinthine inframeatal (6/99, 6.1%), 7) retrolabyrinthine transmeatal (19/99, 19.2%), 8) retrolabyrinthine suprameatal (1/99, 1.0%), and 9) retrolabyrinthine trans-Trautman's triangle (2/99, 2.0%). CONCLUSIONS: Presigmoid approaches are becoming increasingly complex with the expansion of minimally invasive techniques. Descriptions of these approaches using the existing nomenclature can be imprecise or confusing. Therefore, the authors propose a comprehensive classification based on the operative anatomy that unequivocally describes presigmoid approaches simply, precisely, and efficiently.

Cochlear implantation: an effective modality for hearing restoration following vestibular schwannoma resection.

PURPOSE OF REVIEW: Preservation of hearing is one of the tenets of vestibular schwannoma management. In recent years, cochlear implants have been employed with increasing use in patients who have suffered profound sensorineural hearing loss due to the natural history of vestibular schwannoma or due to injury to neurovascular anatomy at time of surgical resection. RECENT FINDINGS: Cochlear implantation has been found to be an effective modality for hearing restoration following vestibular schwannoma. Simultaneous cochlear implantation has been employed by an increased number of centers around the world and has been shown to provide restoration of open set speech perception and return of binaural hearing. Ongoing use of electrically evoked auditory brainstem response (ABR) has improved our detection of viable cochlear nerves and provided insight into those who would benefit from this procedure. Finally, minimally invasive approaches to the internal auditory canal and intralabyrinthine tumors have been described. These methods frequently employ simultaneous cochlear implantation and have emphasized that hearing preservation remains possible with surgical excision despite the location of the tumor. SUMMARY: Cochlear implantation is an effective modality for hearing restoration following vestibular schwannoma excision.

Vestibular Nerve Section via Middle Cranial Fossa Approach.

Vestibular nerve section (VNS) is a surgical intervention with hearing preservation used for the treatment of Menière's disease after conservative medical therapy has failed (1,2). With the recent rise in less invasive treatments such as intratympanic gentamicin, VNS has been performed less frequently (3). The middle cranial fossa (MCF) approach for VNS is an uncommon approach due to its technical difficulty. However, it can provide the best distinction of internal auditory canal contents compared with retrosigmoid and retrolabyrinthine approaches. Several advancements in the MCF approach have been described, including the use of intraoperative facial nerve monitoring with electromyography, early removal of the temporal lobe retractor, and the use of an ultrasonic bone aspirator for internal auditory canal decompression (4-6). We demonstrate a case study with a step-by-step approach to successfully sectioning the superior and inferior vestibular nerves while utilizing these advancements and avoiding facial and cochlear nerve injury via the MCF (7). SDC video link: http://links.lww.com/MAO/B409.

Multi-Disciplinary Skull Base Conference and its Effects on Patient Management.

OBJECTIVE: Examine the effects of a multi-disciplinary skull base conference (MDSBC) on the management of patients seen for skull base pathology in a neurotology clinic. METHODS: Retrospective case review of patients who were seen in a neurotology clinic at a tertiary academic medical center for pathology of the lateral skull base and were discussed at an MDSBC between July 2019 and February 2020. Patient characteristics, nature of the skull base pathology, and pre- and post-MDSBC plan of care was categorized. RESULTS: A total of 82 patients with pathology of the lateral skull base were discussed at a MDSBC during an 8-month study period. About 54 (65.9%) had a mass in the internal auditory canal and/or cerebellopontine angle while 28 (34.1%) had other pathology of the lateral skull base. Forty-nine (59.8%) were new patients and 33 (40.2%) were established. The management plan changed in 11 (13.4%, 7.4-22.6 95% CI) patients as a result of the skull base conference discussion. The planned management changed from some form of treatment to observation in 4 patients, and changed from observation to some form of treatment in 4 patients. For 3 patients who underwent surgery, the planned approach was altered. CONCLUSIONS: For a significant proportion of patients with pathology of the lateral skull base, the management plan changed as a result of discussion at an MDSBC. Although participants of a MDSBC would agree of its importance, it is unclear how an MDSBC affects patient outcomes.