Robotic assistance during cochlear implantation: the rationale for consistent, controlled speed of electrode array insertion.

Cochlear implants (CI) have revolutionized the treatment of patients with severe to profound sensory hearing loss by providing a method of bypassing normal hearing to directly stimulate the auditory nerve. A further advance in the field has been the introduction of "hearing preservation" surgery, whereby the CI electrode array (EA) is carefully inserted to spare damage to the delicate anatomy and function of the cochlea. Preserving residual function of the inner ear allows patients to receive maximal benefit from the CI and to combine CI electric stimulation with acoustic hearing, offering improved postoperative speech, hearing, and quality of life outcomes. However, under the current paradigm of implant surgery, where EAs are inserted by hand, the cochlea cannot be reliably spared from damage. Robotics-assisted EA insertion is an emerging technology that may overcome fundamental human kinetic limitations that prevent consistency in achieving steady and slow EA insertion. This review begins by describing the relationship between EA insertion speed and generation of intracochlear forces and pressures. The various mechanisms by which these intracochlear forces can damage the cochlea and lead to worsened postoperative outcomes are discussed. The constraints of manual insertion technique are compared to robotics-assisted methods, followed by an overview of the current and future state of robotics-assisted EA insertion.

Combining Intraoperative Electrocochleography with Robotics-Assisted Electrode Array Insertion.

OBJECTIVE: To describe the use of robotics-assisted electrode array (EA) insertion combined with intraoperative electrocochleography (ECochG) in hearing preservation cochlear implant surgery. STUDY DESIGN: Prospective, single-arm, open-label study. SETTING: All procedures and data collection were performed at a single tertiary referral center. PATIENTS: Twenty-one postlingually deaf adult subjects meeting Food and Drug Administration indication criteria for cochlear implantation with residual acoustic hearing defined as thresholds no worse than 65 dB at 125, 250, and 500 Hz. INTERVENTION: All patients underwent standard-of-care unilateral cochlear implant surgery using a single-use robotics-assisted EA insertion device and concurrent intraoperative ECochG. MAIN OUTCOME MEASURES: Postoperative pure-tone average over 125, 250, and 500 Hz measured at initial activation and subsequent intervals up to 1 year afterward. RESULTS: Twenty-two EAs were implanted with a single-use robotics-assisted insertion device and simultaneous intraoperative ECochG. Fine control over robotic insertion kinetics could be applied in response to changes in ECochG signal. Patients had stable pure-tone averages after activation with normal impedance and neural telemetry responses. CONCLUSIONS: Combining robotics-assisted EA insertion with intraoperative ECochG is a feasible technique when performing hearing preservation implant surgery. This combined approach may provide the surgeon a means to overcome the limitations of manual insertion and respond to cochlear feedback in real-time.

Evaluation of Real-Time Intracochlear Electrocochleography for Guiding Cochlear Implant Electrode Array Position.

This study evaluates intracochlear electrocochleography (ECochG) for real-time monitoring during cochlear implantation. One aim tested whether adjusting the recording electrode site would help differentiate between atraumatic and traumatic ECochG amplitude decrements. A second aim assessed whether associations between ECochG amplitude decrements and post-operative hearing loss were weaker when considering hearing sensitivity at the ECochG stimulus frequency compared to a broader frequency range. Eleven adult cochlear implant recipients who were candidates for electro-acoustic stimulation participated. Single-frequency (500-Hz) ECochG was performed during cochlear implantation; the amplitude of the first harmonic of the difference waveform was considered. Post-operative hearing preservation at 500 Hz ranged from 0 to 94%. The expected relationship between ECochG amplitude decrements and hearing preservation was observed, though the trend was not statistically significant, and predictions were grossly inaccurate for two participants. Associations did not improve when considering alternative recording sites or hearing sensitivity two octaves above the ECochG stimulus frequency. Intracochlear location of a moving recording electrode is a known confound to real-time interpretation of ECochG amplitude fluctuations, which was illustrated by the strength of the correlation with ECochG amplitude decrements. Multiple factors contribute to ECochG amplitude patterns and to hearing preservation; these results highlight the confounding influence of intracochlear recording electrode location on the ECochG.

Middle Cranial Fossa Approach for Sporadic Vestibular Schwannoma: Patient Selection, Technical Pearls, and Hearing Results.

The middle fossa approach is an excellent technique for removing appropriate vestibular schwannomas in patients with serviceable hearing. Knowledge of the intricate middle fossa anatomy is essential for optimal outcomes. Gross total removal can be achieved with preservation of hearing and facial nerve function, both in the immediate and long-term periods. This article provides an overview of the background and indications for the procedure, a description of the operative protocol, and a summary of the literature on postoperative hearing outcomes.

Shortwave infrared otoscopy for diagnosis of middle ear effusions: a machine-learning-based approach.

Otitis media, a common disease marked by the presence of fluid within the middle ear space, imparts a significant global health and economic burden. Identifying an effusion through the tympanic membrane is critical to diagnostic success but remains challenging due to the inherent limitations of visible light otoscopy and user interpretation. Here we describe a powerful diagnostic approach to otitis media utilizing advancements in otoscopy and machine learning. We developed an otoscope that visualizes middle ear structures and fluid in the shortwave infrared region, holding several advantages over traditional approaches. Images were captured in vivo and then processed by a novel machine learning based algorithm. The model predicts the presence of effusions with greater accuracy than current techniques, offering specificity and sensitivity over 90%. This platform has the potential to reduce costs and resources associated with otitis media, especially as improvements are made in shortwave imaging and machine learning.

The Incidence of Dysphagia Among Patients Undergoing TAVR With Either General Anesthesia or Moderate Sedation.

OBJECTIVES: To determine the incidence of dysphagia and aspiration pneumonia following transcatheter aortic valve replacement (TAVR) performed with either general anesthesia (GA) or moderate sedation (MS). DESIGN: Retrospective study. SETTING: Tertiary care university hospital. PARTICIPANTS: One hundred ninety-seven patients undergoing TAVR from 2012 to 2016 INTERVENTIONS: After Institutional Review Board approval, 197 consecutive patients undergoing TAVR from 2012 to 2016 at the authors' institution were identified for analysis and placed into groups depending on method of anesthesia received (GA: n = 139 v MS: n = 58). Groups then were compared with respect to baseline characteristics, operative details, primary outcome variables (dysphagia, pneumonia), and secondary outcome variables. MEASUREMENT AND MAIN RESULTS: Any patient who failed the institution's postprocedure bedside swallow test subsequently underwent a fiberoptic endoscopic evaluation of swallowing test, confirming the diagnosis of dysphagia. GA patients were significantly more likely to develop dysphagia, which occurred in 10 GA patients and no MS patients (p = 0.04). MS patients also were found to have significantly reduced operative durations and spent less time in the intensive care unit and hospital (p < 0.001). CONCLUSIONS: Patients who underwent TAVR with moderate sedation were less likely to develop dysphagia. Use of MS may be particularly suitable in patients predisposed to swallowing dysfunction.

Use of preoperative aspirin in combined coronary and valve operations.

BACKGROUND: The aim of this study was to determine the relationship between preoperative aspirin use and postoperative outcomes in patients undergoing combined coronary artery bypass grafting and valve operations. METHODS: All combined coronary artery bypass grafting and valve procedures from 2008 to 2015 at our institution were identified. After exclusions, patients were stratified according to those that received preoperative aspirin and those who did not. Propensity score methodology was used to match the 2 groups using baseline and operative characteristics. Logistic regression models were then developed to assess differences in postoperative outcomes between groups. RESULTS: Of the 563 patients identified, 534 met inclusion criteria: preoperative aspirin = 327 (61.2%), no preoperative aspirin = 207 (38.8%). After propensity matching, 194 patient pairs were analyzed, with no significant differences in preoperative characteristics. No significant differences were observed between the preoperative aspirin and no preoperative aspirin groups in rates of 30-day mortality (3.6% vs 4.1%, P = 1.00), major adverse cardiovascular events (23.2% vs 24.2%, P = .91), or 30-day readmission (12.4% vs 11.9%, P = 1.00), among others. CONCLUSION: Preoperative aspirin use in patients undergoing combined coronary artery bypass grafting and valve operations was not associated with significant differences in major postoperative outcomes. Large-scale, randomized trials are needed to better establish the role of preoperative aspirin in this population.

Predicting postoperative atrial fibrillation using CHA2DS2-VASc scores.

BACKGROUND: Postoperative atrial fibrillation (POAF) is the most frequent complication of cardiac surgery and is associated with increased morbidity and mortality. Pharmacologic prophylaxis is the main method of preventing POAF but needs to be targeted to patients at high risk of developing POAF. The CHA2DS2-VASc scoring system is a clinical guideline for assessing ischemic stroke risk in patients with atrial fibrillation. The present study evaluated the utility of this scoring system in predicting the risk of developing de novo POAF in cardiac surgery patients. MATERIALS AND METHODS: A total of 2385 patients undergoing cardiac surgery at our institution from 2008-2014 were identified for analysis. Each patient was assigned a CHA2DS2-VASc score and placed into a low- (score of 0), intermediate- (1), or high-risk (≥2) group. A multivariate regression model was created to control for known risk factors of atrial fibrillation. RESULTS: POAF occurred in 380 of 2385 patients (15.9%). Mean CHA2DS2-VASc scores among patients with POAF and without POAF were 3.6 ± 1.7 and 2.8 ± 1.7, respectively (P < 0.0001). Using multivariate analysis, as a patient's CHA2DS2-VASc score rose from 0-9, the risk of developing POAF increased from 8.2%-42.3%. Each point increase was associated with higher odds of developing POAF (adjusted odds ratio, 1.27; 95% confidence interval, 1.18-1.36, P < 0.0001). Compared with low-risk patients, patients in the high-risk group were 5.21 times more likely to develop POAF (P < 0.0001). CONCLUSIONS: The CHA2DS2-VASc algorithm is a simple risk-stratification tool that could be used to direct pharmacologic prophylaxis toward patients most likely to experience POAF.