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Electrocochleography (ECochG) is an electrophysiological technique that records electrical potentials generated by different components of the inner ear and peripheral cochlear nerve in response to acoustic stimulation. ECochG responses can be analyzed into (1) cochlear microphonics (CM), (2) auditory nerve neurophonics, (3) summating potential, and (4) compound action potential. Over the past few decades, there have been ongoing refinements in technique and updates in the understanding of recorded potentials. Historically, ECochG found its main application in the diagnostic evaluation of Meniere’s disease (MD). However, in the last decade, the focus has shifted towards cochlear implantation (CI). In patients with residual hearing after CI, combined electric and acoustic stimulation has resulted in improved hearing and speech outcomes. Despite efforts to mitigate trauma during electrode insertion, hearing preservation rates vary after surgery. During implantation, real-time ECochG offers an opportunity to measure frequency specific CMs elicited from a localized region in the cochlea as the surgeon inserts the electrode array. In extracochlear ECochG recordings, the recording electrode can be placed on the promontory, the stapes, or the tympanic membrane. Intracochlear ECochG can be performed by inserting a recording electrode into the cochlea or by using one of the CI electrodes as the recording electrode. The loss of intraoperative ECochG signal may indicate cochlear trauma from electrode insertion, but the association between intraoperative ECochG changes and cochlear trauma remains controversial. The ability to monitor cochlear trauma during CI electrode placement holds promise to improve hearing preservation outcomes, modify surgical techniques, and change electrode design. The goal of this review is to provide a comprehensive overview of the electrophysiology and history of ECochG, discuss its recent applications in CI, and explore the ongoing research in this expanding field.

Introduction Ki-67 is often used as a proliferation index to evaluate how aggressive a tumor is and its likelihood of recurrence. Vestibular schwannomas (VS) are a unique benign pathology that lends itself well to evaluation with Ki-67 as a potential marker for disease recurrence or progression following surgical resection. Methods All English language studies of VSs and Ki-67 indices were screened. Studies were considered eligible for inclusion if they reported series of VSs undergoing primary resection without prior irradiation, with outcomes including both recurrence/progression and Ki-67 for individual patients. For published studies reporting pooled Ki-67 index data without detailed by-patient values, we contacted the authors to request data sharing for the current meta-analysis. Studies reporting a relationship between Ki-67 index and clinical outcomes in VS for which detailed patients' outcomes or Ki-67 indices could not be obtained were incorporated into the descriptive analysis, but excluded from the formal (i.e., quantitative) meta-analysis. Results A systematic review identified 104 candidate citations of which 12 met inclusion criteria. Six of these studies had accessible patient-specific data. Individual patient data were collected from these studies for calculation of discrete study effect sizes, pooling via random-effects modeling with restricted maximum likelihood, and meta-analysis. The standardized mean difference in Ki-67 indices between those with and without recurrence was calculated as 0.79% (95% confidence interval [CI]: 0.28–1.30; p = 0.0026). Conclusion Ki-67 index may be higher in VSs that demonstrate recurrence/progression following surgical resection. This may represent a promising means of evaluating tumor recurrence and potential need for early adjuvant therapy for VSs.

Background Translational research refers to scientific findings that have been extensively studied in models and find their way to clinical studies. In a certain sense in translational anatomy a similar application of conventional anatomical knowledge finds its way to clinics in the surgical theatre. With the propagation of endoscopic middle ear surgery there has been a renewed interest in many early anatomical terms, even many years after their discovery, which may threaten the correct and classic eponyms. Moreover, the application of robotic ear surgery executing minimal invasive keyhole accesses requires translation of anatomical knowledge to the sub-millimetric level. Purpose This review reports relevant anatomy of the temporal bone for robotic cochlear implantation reflecting also on recent revisions of terminology. Results In 2019, the Terminologia Neuroanatomica (TNA 2017) was accepted at the 19th World Congress of the International Federation of Associations of Anatomists (IFAA) in London as its official terminology for the central and peripheral nervous system and the sense organs. This review follows the terminology of in the TNA, but also compares anatomical and clinical terms to bridge the gap between both approaches, and provides brief descriptions and illustrations of relevant structures for robotic cochlear implantation and elaborates on their significance. With the emergence and more widespread use of the endoscopic ear surgery and image guided ear surgery, visualization of certain anatomical structures has improved. Coinciding, there has been a renewed interest in many early anatomical terms, even many years after their discovery, which may threaten the correct and classic eponyms. Conclusions Consequently, this review also presents an overview of eponyms associated with specific structures over the years. In Supplementary Tables, the changes in terminology are reported.

Postoperative temporal bone imaging after surgical procedures such as ossiculoplasty, tympanomastoidectomy, cochlear implantation, and vestibular schwannoma resection is often encountered in clinical neuroradiology practice. Less common otologic procedures can present diagnostic dilemmas, particularly if access to prior operative reports is not possible. Lack of familiarity with the less common surgical procedures and expected postoperative changes may render radiologic interpretation challenging. This review illustrates key imaging findings after surgery for Meniere disease, superior semicircular canal dehiscence, temporal encephalocele repairs, internal auditory canal decompression, active middle ear implants, jugular bulb and sigmoid sinus dehiscence repair, and petrous apicectomy.

International audience; Importance Cochlear implants are a treatment option for individuals with severe, profound, or moderate sloping to profound bilateral sensorineural hearing loss (SNHL) who receive little or no benefit from hearing aids; however, cochlear implantation in adults is still not routine.Objective To develop consensus statements regarding the use of unilateral cochlear implants in adults with severe, profound, or moderate sloping to profound bilateral SNHL.Design, Setting, and Participants This study was a modified Delphi consensus process that was informed by a systematic review of the literature and clinical expertise. Searches were conducted in the following databases: (1) MEDLINE In-Process & Other Non-Indexed Citations and Ovid MEDLINE, (2) Embase, and (3) the Cochrane Library. Consensus statements on cochlear implantation were developed using the evidence identified. This consensus process was relevant for the use of unilateral cochlear implantation in adults with severe, profound, or moderate sloping to profound bilateral SNHL. The literature searches were conducted on July 18, 2018, and the 3-step Delphi consensus method took place over the subsequent 9-month period up to March 30, 2019.Main Outcomes and Measures A Delphi consensus panel of 30 international specialists voted on consensus statements about cochlear implantation, informed by an SR of the literature and clinical expertise. This vote resulted in 20 evidence-based consensus statements that are in line with clinical experience. A modified 3-step Delphi consensus method was used to vote on and refine the consensus statements. This method consisted of 2 rounds of email questionnaires and a face-to-face meeting of panel members at the final round. All consensus statements were reviewed, discussed, and finalized at the face-to-face meeting.Results In total, 6492 articles were identified in the searches of the electronic databases. After removal of duplicate articles, 74 articles fulfilled all of the inclusion criteria and were used to create the 20 evidence-based consensus statements. These 20 consensus statements on the use of unilateral cochlear implantation in adults with SNHL were relevant to the following 7 key areas of interest: level of awareness of cochlear implantation (1 consensus statement); best practice clinical pathway from diagnosis to surgery (3 consensus statements); best practice guidelines for surgery (2 consensus statements); clinical effectiveness of cochlear implantation (4 consensus statements); factors associated with postimplantation outcomes (4 consensus statements); association between hearing loss and depression, cognition, and dementia (5 consensus statements); and cost implications of cochlear implantation (1 consensus statement).Conclusions and Relevance These consensus statements represent the first step toward the development of international guidelines on best practices for cochlear implantation in adults with SNHL. Further research to develop consensus statements for unilateral cochlear implantation in children, bilateral cochlear implantation, combined electric-acoustic stimulation, unilateral cochlear implantation for single-sided deafness, and asymmetrical hearing loss in children and adults may be beneficial for optimizing hearing and quality of life for these patients.

Fourteen single-sided deaf listeners fit with an MED-EL cochlear implant (CI) judged the similarity of clean signals presented to their CI and modified signals presented to their normal-hearing ear. The signals to the normal-hearing ear were created by (a) filtering, (b) spectral smearing, (c) changing overall fundamental frequency (F0), (d) F0 contour flattening, (e) changing formant frequencies, (f) altering resonances and ring times to create a metallic sound quality, (g) using a noise vocoder, or (h) using a sine vocoder. The operations could be used singly or in any combination. On a scale of 1 to 10 where 10 was a complete match to the sound of the CI, the mean match score was 8.8. Over half of the matches were 9.0 or higher. The most common alterations to a clean signal were band-pass or low-pass filtering, spectral peak smearing, and F0 contour flattening. On average, 3.4 operations were used to create a match. Upshifts in formant frequencies were implemented most often for electrode insertion angles less than approximately 500°. A relatively small set of operations can produce signals that approximate the sound of the MED-EL CI. There are large individual differences in the combination of operations needed. The sound files in Supplemental Material approximate the sound of the MED-EL CI for patients fit with 28-mm electrode arrays.

OBJECTIVE: Closely paralleling prior radiologic studies, recent population-based prevalence data suggest sporadic vestibular schwannoma (VS) affects over 1 in 2,000 adults and up to 1 in 500 in those aged 70 years or older. Attributable to increased utilization of magnetic resonance imaging and screening protocols for asymmetrical sensorineural hearing loss, the increasing detection rate of sporadic VS fundamentally changes the perception of VS as a whole. The primary objective of the current study was to contextualize modern epidemiological trends in neurofibromatosis type 2 (NF2) in light of these recent advancements in the understanding of sporadic VS. STUDY-DESIGN: Population-based study. SETTING: Olmsted County, Minnesota. Population size on 1 Jan 2017: 159,689 people. PATIENTS: All patients with NF2 diagnosed between 1 Jan 1966 to 31 Dec 2016, identified using the Rochester Epidemiology Project. MAIN OUTCOME MEASURES: Incidence, prevalence. RESULTS: Six incident cases were identified over the past 50 years, representing 3.8% of all incident VSs diagnosed over this period. From 1966–2016, the age- and sex-adjusted incidence rate was 0.10 per 100,000 person-years. The incidence rate remained at 0.12 over the most recent decade. Five cases met disease prevalence criteria, and the age- and sex-adjusted prevalence of NF2 on 1 Jan 2017 was 3.1 per 100,000 persons. All prevalent cases were women, and the resultant prevalence among women only was 6.0 per 100,000 persons. Disease prevalence peaked in those aged 40–49 at 34.4 per 100,000 persons. CONCLUSIONS: The modern age- and sex-adjusted incidence and prevalence rate of NF2 is 0.10 per 100,000 person-years and 3.1 per 100,000 persons, respectively. In contrast to trends in incidence rates of sporadic VS over the last half-century, this study demonstrates that the incidence of NF2 has remained relatively stable since 1966. This divergence in epidemiological trends is likely attributed to the nature of NF2, with early clinical manifestations resulting in diagnosis regardless of modern advances, whereas the increased incidence of sporadic VS is heavily influenced by improved detection in a greater population of patients with minimally symptomatic or asymptomatic tumors.

OBJECTIVE: Several reports have suggested that the incidence of otosclerosis is declining. However, due to the limitations of epidemiologic databases within the United States, little is known about the incidence of congenital stapes footplate fixation (CSFF), much less epidemiological trends over the past 50 years. The current study was conceived to characterize the epidemiology of CSFF over the past five decades using the unique resources of the Rochester Epidemiology Project (REP). STUDY DESIGN: Population-based study. PATIENTS: The medical records of every resident of Olmsted County, Minnesota who was diagnosed with CSFF was reviewed from January 1, 1970 to December 12, 2017 using the REP. The population of Olmsted County on January 1, 2017 was 159,689 persons. MAIN OUTCOME MEASURE: Incidence of CSFF. RESULTS: Sixteen cases of CSFF were identified at a median age at diagnosis of 8 years (IQR, 6–17), eight of whom confirmed by exploratory tympanotomy. Three of the 16 (19%) cases were bilateral, and the median pure-tone average (500, 1k, 2k, 3k Hz) at time of diagnosis was 37 dB (IQR, 31–48). Two (13%) cases were identified in patients bearing a syndromic condition and one (6%) case demonstrated a malformed external ear on physical examination. The incidence rate of surgically confirmed cases among residents of Olmsted County was 0.31 per 100,000 person-years from 1970 to 1979 and 0.28 from 2000 to 2009. No incident cases among residents of Olmsted County were identified since 2010. CONCLUSIONS: CSFF constitutes a rare disease. Unlike epidemiological trends in otosclerosis, the incidence of surgically confirmed cases of CSFF remained stable over the past 50 years.

Rare ecosystems support unique assemblages of flora and fauna within a small geographic area. As such, their conservation represents an effective method of biodiversity protection. The description, mapping, and assessment of rare ecosystems is a necessary and initial conservation action, yet this has not been completed for Alaska. Here, we provide the first comprehensive treatment of rare terrestrial ecosystems for the state. Thirty‐five rare systems, representing different levels of ecological organization and geographic scale, are presented. In addition, a gap analysis was conducted to evaluate the systems' current level of land management protection relative to their conservation need. Eleven of the mapped ecosystems are considered adequately protected, two are moderately protected, and 22 are less protected. Conservation ranks are incongruously aligned with land management protection levels such that the rarest systems are often not well protected and the less‐imperiled systems are often well protected. On the ecoregion scale, systems with arctic distributions are less protected than are those with boreal and maritime distributions. This rare ecosystem assessment complements species‐ and landscape‐scale conservation studies previously completed for Alaska. Collectively, the recommendations from these assessments provide a science‐based strategy for biological conservation in a vulnerable region of the world.

Objectives To present a rare case of traumatic facial neuroma involving the geniculate ganglion and review relevant literature. Patient Thirty-year-old man. Intervention Microsurgical resection via combined mastoid-middle fossa approach with great auricular nerve interpositional graft. Main Outcome Measures Patient demographics and pre- and postoperative facial nerve function. Results A 30-year-old man with a reported history of prior Bell's palsy developed progressive complete (House–Brackmann VI) right facial paralysis following blunt trauma. Imaging was strongly suggestive of a geniculate ganglion hemangioma. As the patient had no spontaneous improvement in his poor facial function over the course of 9 months, he underwent resection of the facial nerve lesion with great auricular nerve graft interposition via a combined mastoid-middle fossa approach. Histopathology demonstrated disorganized fascicles, with axonal clustering reminiscent of sprouting/regeneration following trauma. No cellular proliferation or vascular malformation was present. Conclusion Traumatic facial nerve neuromas can occur following temporal bone trauma and can closely mimic primary facial nerve tumors. Akin to the management of geniculate ganglion hemangioma and schwannoma, preoperative facial function largely dictates if and when surgery should be pursued.

Background Cahan's criteria have been utilized since 1948 to establish causality between prior radiation treatment and the development of secondary malignancy. One major criterion specifies that histological and radiographic evidence collected before and after radiation treatment must confirm separate tumor types; however, pretreatment biopsy is rarely obtained prior to radiosurgery for vestibular schwannoma and many other skull base and cranial lesions. Therefore, in these cases Cahan's criteria cannot be validly applied. Objective This article proposes an update to Cahan's criteria using modern molecular genetic analysis for cases lacking baseline histopathology. Methods Mate-pair sequencing and whole exome sequencing of a cerebellopontine angle undifferentiated high-grade pleomorphic sarcoma (UHGPS) that developed after stereotactic radiosurgery of a presumed benign vestibular schwannoma. Results Mate-pair sequencing and whole exome sequencing of the sarcoma revealed complex chromosomal aberrations. Notably, the tumor contained a deletion in the NF2 gene at 22q12 and an in-frame deletion on exon 5 of the remaining copy of NF2. Biallelic events impacting NF2 are atypical for UHGPS but are characteristic for vestibular schwannoma. These findings help support the conclusion that the UHGPS arose from a benign vestibular schwannoma all along. Conclusions Next-generation sequencing can be successfully applied to a radiation-induced sarcoma when both the original and malignant tumors harbor separate signature genetic markers. As our understanding of the genetic profile of various tumors expand, we believe that next-generation sequencing and other genomic tools will play an increasingly important role in establishing causality between radiation and the development of secondary malignancy.

Introduction. Charcot-Marie-Tooth (CMT) disease is a peripheral hereditary neuropathy associated with motor and sensory impairment and can result in profound sensorineural hearing loss (SNHL). Currently, the role of cochlear implantation in the setting of CMT and other progressive peripheral neurodegenerative disorders is not well established. Methods. Case report and review of the English literature. Results. A 70-year-old male with CMT was referred for evaluation of progressive asymmetric SNHL and reported a 15-year duration of deafness involving the left ear. Audiometric testing confirmed profound SNHL in the left ear, while the right ear exhibited moderate-to-severe SNHL. Left-sided cochlear implantation was performed using a conventional length lateral wall electrode. Intraoperative device testing found normal impedance levels throughout the array; however, electrically evoked auditory potentials were absent on all electrodes. Upon initial activation 3 weeks after surgery, the patient reported excellent access to sound in the cochlear implant-only condition. He has made good progress at each subsequent visit; speech perception testing after seven months showed improvement from 0% to 32% on AzBio sentence and 53% on CNC phoneme testing in the cochlear implant-only condition. Conclusion. We report the third case of cochlear implantation in a patient with CMT. SNHL in CMT is hypothesized to result from disruption of synchronous activity of the cochlear nerve. In patients with CMT, cochlear implantation may reconstitute synchronous neural activity by way of supraphysiological electrical stimulation. Our results corroborate two earlier reports that cochlear implantation is a viable option for rehabilitation of SNHL in this unique subset of patients.

OBJECTIVE To correlate objective measures of vestibular and audiometric function as well as subjective measures of dizziness handicap with the surface area of the superior canal dehiscence (SCD). STUDY DESIGN Retrospective chart review and radiological analysis. SETTING Single tertiary academic referral center. PATIENTS Preoperative computed tomography imaging, patient survey, audiometric thresholds, and vestibular evoked myogenic potential (VEMP) testing in patients with confirmed SCD. INTERVENTION(S) Image analysis techniques were developed to measure the surface area of each SCD in computed tomography imaging. MAIN OUTCOME MEASURE(S) Preoperative ocular and cervical VEMPs, air and bone conduction thresholds, air-bone gap, dizziness handicap inventory scores, and surface area of the SCD. RESULTS Fifty-three patients (mean age 52.7 yr) with 84 SCD were analyzed. The median surface area of dehiscence was 1.44 mm (0.068-8.23 mm). Ocular VEMP amplitudes (r = 0.61, p

The objective of this study was to evaluate the role of removing middle ear paragangliomas using an ultrasonic aspirator (UA) through a transcanal, exclusively endoscopic approach. Three consecutive patients undergoing transcanal endoscopic resection of middle ear paragangliomas using an UA were retrospectively studied. The primary outcome measure was achieving gross total tumor resection. Secondary outcomes included postoperative hearing and early convalescence. Two glomus tympanicum tumors and one small glomus jugulare were included, and complete tumor resection was achieved endoscopically in all cases. All patients demonstrated intact tympanic membranes and normal facial nerve function at the initial postoperative visit. There were no cases of bone-conduction pure tone threshold increases of more than 15 dB. The UA was helpful when performing exclusively endoscopic transcanal resection of middle ear paraganglioma given its simultaneous suction-aspiration capability.

To analyze factors that influence hearing preservation over time in cochlear implant recipients with conventional-length electrode arrays located entirely within the scala tympani.Case series with planned chart review.Single tertiary academic referral center.A retrospective review was performed to analyze a subgroup of cochlear implant recipients with residual acoustic hearing. Patients were included in the study only if their electrode arrays remained fully in the scala tympani after insertion and serviceable acoustic hearing (≤80 dB at 250 Hz) was preserved. Electrode array location was verified through a validated radiographic assessment tool. Patients with6 months of audiologic follow-up were excluded. The main outcome measure was change in acoustic hearing thresholds from implant activation to the last available follow-up.A total of 16 cases met inclusion criteria (median age, 70.6 years; range, 29.4-82.2; 50% female). The average follow-up was 18.0 months (median, 16.1; range, 6.2-36.4). Patients with a lateral wall electrode array were more likely to have stable acoustic thresholds over time (P.05). Positive correlations were seen between continued hearing loss following activation and larger initial postoperative acoustic threshold shifts, though statistical significance was not achieved. Age, sex, and noise exposure had no significant influence on continued hearing preservation over time.To control for hearing loss associated with interscalar excursion during cochlear implantation, the present study evaluated patients only with conventional electrode arrays located entirely within the scala tympani. In this group, the style of electrode array may influence residual hearing preservation over time.

A 7-year-old male with a history of submucous cleft palate, congenital heart disease, and torticollis presented with since-birth right-sided hearing loss. The patient had no previous otologic history other than pressure equalization tube placement at 9 months of age. Audiometric evaluation revealed normal hearing thresholds on the left with a maximal conductive hearing loss on the right side without a distinct Carhart notch (Fig. 1A). Fine cut computed tomography (CT) of the temporal bones was obtained demonstrating bilateral well-aerated mastoid and middle ear cavities with normal inner ear morphology; specifically, the right cochlea was not dysplastic and the vestibular aqueduct was normal in size. The right ear demonstrated a malformed long process of the incus, a thinned stapes suprastructure and a thickened footplate. The labyrinthine and mastoid segments of the facial nerve appeared within normal limits, while the tympanic portion was poorly defined but appeared to straddle the oval window (Fig. 2 & 3). The contralateral middle ear was radiographically unremarkable. Figure 1 A, Pre-operative audiogram revealing a maximal conductive loss without a Cahart notch. B, Post-operative audiogram demonstrating a 52 dB pure-tone average gain with a residual 17 dB air-bone gap and unchanged bone conduction thresholds. Figure 2 High-resolution axial and coronal CT of a right temporal bone with congenital footplate fixation and a bifid tympanic facial nerve segment. A, Axial CT demonstrating a fibrous malformed stapes suprastructure (white arrow) and a thickened non-distinct ... Figure 3 For illustration purposes, a preoperative CT of a normal temporal bone and the CT of the index patient were segmented using automated software in order to create 3-dimensional renderings of the fallopian canal (magenta), ossicles (blue) and inner ear ... After informed consent, the patient and family elected to proceed with middle ear exploration and possible stapedotomy. The tympanomeatal flap was elevated and palpation of the malleus and incus revealed normal mobility, however the incus and stapes were severely malformed. The long process of the incus was foreshortened and slightly medially rotated with a malformed lenticular process and the stapes crurae were merely fibrous bands connected to a thick, immobile footplate. The tympanic segment of the facial nerve was noted to be distinctly bifid, coursing around the footplate superiorly and inferiorly (Fig 4). Facial nerve stimulation confirmed an anomalous split facial nerve configuration. A stapedotomy was carefully performed using a microdrill until the footplate was “blue lined” and a CO2 laser with micropick was used to open the vestibule. A 4-mm self-crimping Nitinol stapes prosthesis was placed without difficulty and the patient awoke from anesthesia with normal facial nerve function and Weber examination lateralized to the operative ear. Three months following surgery the patient was noted to have persistent bilateral serous effusions and progressive anterior pars tensa retraction requiring tympanostomy tube placement. Follow-up audiometry was performed approximately 4 months following surgery and demonstrated a 52 dB improvement in pure-tone average with a residual 17dB air-bone gap; bone conduction thresholds remained unchanged (Fig 1B). Figure 4 A, Endoscopic view of the anomalous facial nerve prior to removing the stapes suprastructure. B–D With the stapes suprastructure removed, the bifid facial nerve can be clearly seen coursing superior and inferior to the stapes footplate. (FN=facial ... Stapes footplate fixation is known to be the most prevalent congenital ossicular abnormality.3 The common embryologic origin, shared by the facial nerve, long process of the incus, stapes suprastrucure and outer table of the footplate helps explain the constellation of findings within the present case. While rare, an aberrant facial nerve course is more common among patients with external auditory canal atresia or dysplastic inner ears. While even less common, an anomalous tympanic course can also be seen in patients with congenital footplate fixation, having normal external and inner ears.3,4 In contrast to juvenile otosclerosis, congenital footplate fixation presents with a life-long, non-progressive conductive hearing loss. While audiometric findings are somewhat variable, most patients are diagnosed with advanced conductive hearing loss, often without a distinct Carhart notch. All pediatric patients undergoing stapedectomy should be evaluated with preoperative CT to rule out inner ear malformations and the associated risk of gusher. The above case demonstrates the importance of understanding and applying embryology during otologic surgery. When a surgeon encounters an anatomic anomaly intraoperatively, they must carefully inspect other structures with similar embryologic origins to avoid misadventure.

Objectives To report a novel modification of the cochlear drill-out procedure that uses customized microstereotactic frames as drill guides. Patient(s) A 34-year-old man with an 18-year history of profound bilateral hearing loss and completely ossified cochleae that underwent a previous unsuccessful conventional cochlear drill-out procedure in the contralateral ear. Interventions Image-guided cochlear implantation using customized microstereotactic frames to drill linear basal and apical cochlear tunnels. Main outcome measures Transfacial recess cochlear drill-out procedure with full electrode insertion. Results Two linear paths were drilled using customized microstereotactic frames targeting the proximal and distal basal turn followed by a full split array insertion. Postoperative imaging confirmed 2 cochlear tunnels straddling the modiolus with adequate clearance of the facial nerve and internal carotid artery. The patient received auditory benefit with device use and did not experience any surgical complication. Conclusion Successful cochlear implantation in the setting of total scalar obliteration poses a significant challenge. Image guidance technology may assist in navigating the ossified cochlea facilitating safe and precise cochlear tunnel drilling.

Revision surgery using a newer-generation conventional length cochlear implant electrode will provide improved speech perception in patients that initially underwent hybrid electrode implantation and experienced post-operative loss of residual hearing and performance deterioration.We present four patients who experienced delayed post-operative hearing loss following implantation with the Nucleus Hybrid S8 device and underwent reimplantation with the Nucleus Freedom or Nucleus 5 device using the Contour Advance array. Pure-tone thresholds and speech perception data were retrospectively reviewed.Four subjects underwent reimplantation with the Nucleus Freedom or Nucleus 5 device after experiencing deteriorating performance related to delayed acoustic hearing loss. Comparison of pre-revision performance to the most recent post-revision performance demonstrated improved speech perception performance in all subjects following reimplantation.A small percent of patients will experience a significant loss of residual low-frequency hearing following hybrid implantation thereby becoming completely reliant on a shorter electrode for electrical stimulation. In the current series, reimplantation with a conventional length electrode provided improved speech perception performance in such patients. Revision surgery with a conventional length electrode should be considered in 'short electrode' recipients who experience performance deterioration following loss of residual hearing.

Intra- and interspecific variation in flower color is a hallmark of angiosperm diversity. The evolutionary forces underlying the variety of flower colors can be nearly as diverse as the colors themselves. In addition to pollinator preferences, non-pollinator agents of selection can have a major influence on the evolution of flower color polymorphisms, especially when the pigments in question are also expressed in vegetative tissues. In such cases, identifying the target(s) of selection starts with determining the biochemical and molecular basis for the flower color variation and examining any pleiotropic effects manifested in vegetative tissues. Herein, we describe a widespread purple-white flower color polymorphism in the mustard Parrya nudicaulis spanning Alaska. The frequency of white-flowered individuals increases with increasing growing-season temperature, consistent with the role of anthocyanin pigments in stress tolerance. White petals fail to produce the stress responsive flavonoid intermediates in the anthocyanin biosynthetic pathway (ABP), suggesting an early pathway blockage. Petal cDNA sequences did not reveal blockages in any of the eight enzyme-coding genes in white-flowered individuals, nor any color differentiating SNPs. A qRT-PCR analysis of white petals identified a 24-fold reduction in chalcone synthase (CHS) at the threshold of the ABP, but no change in CHS expression in leaves and sepals. This arctic species has avoided the deleterious effects associated with the loss of flavonoid intermediates in vegetative tissues by decoupling CHS expression in petals and leaves, yet the correlation of flower color and climate suggests that the loss of flavonoids in the petals alone may affect the tolerance of white-flowered individuals to colder environments.

Kikuchi-Fujimoto disease is a rare, self-limited, histiocytic, necrotizing lymphadenitis first described in Japan in 1972. Necrosis of lymph node tissue is caused by apoptosis and may be virally induced. It commonly presents with cervical lymphadenitis and fever. Despite its low incidence, Kikuchi-Fujimoto disease should be considered in patients with persistent lymphadenopathy. Originally thought to occur only in young Asian women, it is now recognized in other geographic regions. We report a 30-year-old white woman with Kikuchi-Fujimoto disease. We discuss the clinical features, differential diagnosis, radiography, pathology, and outcome.

Introduced non-native fishes have the potential to substantially alter aquatic ecology in the introduced range through competition and predation. The Alaska blackfish (Dallia pectoralis) is a freshwater fish endemic to Chukotka and Alaska north of the Alaska Range (Beringia); the species was introduced outside of its native range to the Cook Inlet Basin of Alaska in the 1950s, where it has since become widespread. Here we characterize the diet of Alaska blackfish at three Cook Inlet Basin sites, including a lake, a stream, and a wetland. We analyze stomach plus esophageal contents to assess potential impacts on native species via competition or predation. Alaska blackfish in the Cook Inlet Basin consume a wide range of prey, with major prey consisting of epiphytic/benthic dipteran larvae, gastropods, and ostracods. Diets of the introduced populations of Alaska blackfish are similar in composition to those of native juvenile salmonids and stickleback. Thus, Alaska blackfish may affect native fish populations via competition. Fish ranked third in prey importance for both lake and stream blackfish diets but were of minor importance for wetland blackfish.