No abstract

Optogenetics is a transformative technology based on light-sensitive microbial proteins, known as opsins, that enable precise modulation of neuronal activity with pulsed radiant energy. Optogenetics has been proposed as a means to improve auditory implant outcomes by reducing channel interaction and increasing electrode density, but the introduction of opsins into cochlear spiral ganglion neurons (SGNs) in vivo has been challenging. Here we test opsin delivery using a synthetically developed ancestral adeno-associated virus (AAV) vector called Anc80L65. Wild-type C57BL/6 mouse pups were injected via the round window of cochlea with Anc80L65 carrying opsin Chronos under the control of a CAG promoter. Following an incubation of 6-22 weeks, pulsed blue light was delivered to cochlear SGNs via a cochleosotomy approach and flexible optical fiber. Optically evoked auditory brainstem responses (oABRs) and multiunit activity in inferior colliculus (IC) were observed. Post-experiment cochlear histology demonstrated opsin expression in SGNs (mean = 74%), with an even distribution of opsin along the cochlear basal/apical gradient. This study is the first to describe robust SGN transduction, opsin expression, and optically evoked auditory electrophysiology in neonatal mice. Ultimately, this work may provide the basis for a new generation of cochlear implant based on light.

ObjectiveOtogenic brain abscesses are one of the most significant life‐threatening complications of otologic infections. Given their low prevalence, otogenic brain abscesses require a high index of suspicion for diagnosis. In this systematic review, we aim to provide an analysis of otogenic brain abscesses and describe common clinical signs and symptoms, bacteriology, location, treatment options, morbidity, and mortality.Data SourcesPubMed, Cochrane CENTRAL database, Google Scholar, and Scopus.MethodsA systematic review of literature was performed using the Preferred Reporting Items for Systematic Reviews and Meta‐analyses recommendations. Variables assessed included clinical signs and symptoms, bacteriology, location, treatment, morbidity, and mortality.ResultsTwenty‐nine studies met inclusion and exclusion criteria, corresponding to a total of 1307 otogenic abscess cases for review. Fifty‐five percent of abscesses were found in the temporal lobe and 28% in the cerebellum. Most patients (88.3%) had a history of suppurative chronic otitis media. The most common symptoms were headache, altered mental status, papilledema, and meningeal irritation. Fever, nausea, and vomiting affected about 40% of patients. The most commonly cultured bacterial species was Proteus mirabilis. In addition to antibiotics, most otogenic brain abscesses were treated by burr hole aspiration. Average mortality following advent of computed tomography was 8.11%.ConclusionAlthough rare, otogenic brain abscesses may occur as a complication of suppurative otitis media and require a high index of suspicion. Appropriate imaging studies and multidisciplinary expertise are crucial in the diagnosis and management.Level of Evidence4.

This is the largest study to date examining the usefulness of cVEMPs in the diagnosis of SCD. Our "third window indicator" (TWI) combines cVEMP thresholds with the ABG at 250 Hz to improve the ability to screen patients with SCD symptoms.

While threshold audiometry and cVEMP are important tools to diagnose SCD and monitor surgical outcomes, these measures showed no significant correlation with vestibular and most auditory symptoms or their severity.

Evaluation of resident operative skills is challenging in the fast-paced operating room environment and limited by lack of validated assessment metrics. We describe a smartphone-based app that enables rapid assessment of operative skills. Accreditation Council for Graduate Medical Education (ACGME) otolaryngology taxonomy surgical procedures (n = 593) were uploaded to the software platform. The app was piloted over 1 month. Outcomes included (1) completion of evaluation, (2) time spent completing the evaluation, and (3) quantification of case complexity, operative autonomy, and performance. During the study, 12 of 12 procedures, corresponding to 3 paired evaluated by the resident/attending dyad. Mean ± SD time of evaluation completion was 98.0 ± 24.2 and 123.0 ± 14.0 seconds for the resident and attending, respectively. Mean time between resident and attending evaluation completion was 27.9 ± 26.8 seconds. Resident and attending scores for case complexity, operative autonomy, and performance were strongly correlated (P < .0001). Rapid evaluation of resident intraoperative performance is feasible using smartphone-based technology.

Similar to the case of device implantation, device explantation should be a multidisciplinary and collaborative decision with the patient and the family's desires at the centre. While every case is different, we offer a CI explantation discussion to assist in clinical decision-making, patient counselling and education.

ObjectiveOtologic methicillin-resistant Staphylococcus aureus (MRSA) infection has historically been rare, but given the rise in community-acquired MRSA carriage and infection at other body sites, prevalence rates may be changing. The goal of this study was to determine the prevalence of MRSA in recent otologic cultures from patients with acute otitis externa (AOE).Study designRetrospective review of an institutional microbiologic database.MethodsA retrospective analysis was performed on serial culture isolates taken from the ear at a quaternary care hospital from January 2014 to April 2016. The causative pathogen and antibiotic sensitivity was determined by culture isolation and end point mean inhibitory concentration (MIC) testing. Medical records were reviewed to document patient characteristics, chronicity of infection, symptomatology, and previous treatments.ResultsOver the study period, 173 patients were diagnosed with AOE and underwent otologic cultures of the ear. Fifty-three (30.6%) of cultures grew S.aureus (SA). Of SA infections, 15 (28.3%) were identified as MRSA. MRSA patients were typically older than patients with methicillin-sensitive SA (MSSA) (mean age 46.7 ± 17.9 vs 29 ± 19.4, P = 0.003) and had more medical comorbidities (4 vs 1.7, P = 0.001). Compared to patients with MSSA, patients with MRSA were significantly more likely to have had prior ototopical antibiotic exposure (37% vs 73%, P = 0.019).ConclusionContemporary ear culture isolates at quaternary care center show higher rates of MRSA compared to historical reports in the literature. Clinicians should consider ear cultures to identify MRSA AOE.Level of EvidenceIV.