Suitable Electrode Choice for Robotic-Assisted Cochlear Implant Surgery: A Systematic Literature Review of Manual Electrode Insertion Adverse Events.

Background and Objective: The cochlear implant (CI) electrode insertion process is a key step in CI surgery. One of the aims of advances in robotic-assisted CI surgery (RACIS) is to realize better cochlear structure preservation and to precisely control insertion. The aim of this literature review is to gain insight into electrode selection for RACIS by acquiring a thorough knowledge of electrode insertion and related complications from classic CI surgery involving a manual electrode insertion process. Methods: A systematic electronic search of the literature was carried out using PubMed, Scopus, Cochrane, and Web of Science to find relevant literature on electrode tip fold over (ETFO), electrode scalar deviation (ESD), and electrode migration (EM) from both pre-shaped and straight electrode types. Results: A total of 82 studies that include 8,603 ears implanted with a CI, i.e., pre-shaped (4,869) and straight electrodes (3,734), were evaluated. The rate of ETFO (25 studies, 2,335 ears), ESD (39 studies, 3,073 ears), and EM (18 studies, 3,195 ears) was determined. An incidence rate (±95% CI) of 5.38% (4.4-6.6%) of ETFO, 28.6% (26.6-30.6%) of ESD, and 0.53% (0.2-1.1%) of EM is associated with pre-shaped electrodes, whereas with straight electrodes it was 0.51% (0.1-1.3%), 11% (9.2-13.0%), and 3.2% (2.5-3.95%), respectively. The differences between the pre-shaped and straight electrode types are highly significant (p < 0.001). Laboratory experiments show evidence that robotic insertions of electrodes are less traumatic than manual insertions. The influence of round window (RW) vs. cochleostomy (Coch) was not assessed. Conclusion: Considering the current electrode designs available and the reported incidence of insertion complications, the use of straight electrodes in RACIS and conventional CI surgery (and manual insertion) appears to be less traumatic to intracochlear structures compared with pre-shaped electrodes. However, EM of straight electrodes should be anticipated. RACIS has the potential to reduce these complications.

Comprehensive metrics for evaluating surgical microscope use during tympanostomy tube placement.

PURPOSE: Learning to use a surgical microscope is a fundamental step in otolaryngology training; however, there is currently no objective method to teach or assess this skill. Tympanostomy tube placement is a common otologic procedure that requires skilled use of a surgical microscope. This study was designed to (1) implement metrics capable of evaluating microscope use and (2) establish construct validity. STUDY DESIGN: This was a prospective cohort study. METHODS: Eight otolaryngology trainees and three otolaryngology experts were asked to use a microscope to insert a tympanostomy tube into a cadaveric myringotomy in a standardized setting. Microscope movements were tracked in a three-dimensional space, and tracking metrics were applied to the data. The procedure was video-recorded and then analyzed by blinded experts using operational metrics. Results from both groups were compared, and discriminatory metrics were determined. RESULTS: The following tracking metrics were identified as discriminatory between the trainee and expert groups: total completion time, operation time, still time, and jitter (movement perturbation). Many operational metrics were found to be discriminatory between the two groups, including several positioning metrics, optical metrics, and procedural metrics. CONCLUSIONS: Performance metrics were implemented, and construct validity was established for a subset of the proposed metrics by discriminating between expert and novice participants. These discriminatory metrics could form the basis of an automated system for providing feedback to residents during training while using a myringotomy surgical simulator. Additionally, these metrics may be useful in guiding a standardized teaching and evaluation methodology for training in the use of surgical microscopes.

Quality Indicators for the Diagnosis and Management of Sudden Sensorineural Hearing Loss.

OBJECTIVE: Sudden sensorineural hearing loss (SSNHL) is an ideal entity for quality indicator (QI) development, providing treatment challenges resulting in variable or substandard care. The American Academy of Otolaryngology-Head and Neck Surgery recently updated their SSNHL guidelines. With SSNHL demonstrating a large burden of illness, this study sought to leverage the updated guidelines and develop QIs that support quality improvement initiatives at an individual, institutional, and systems level. METHODS: Candidate indicators (CIs) were extracted from high-quality SSNHL guidelines that were evaluated using the Appraisal of Guidelines for Research and Evaluation II tool. Each CI and its supporting evidence were summarized and reviewed by a nine-member expert panel based on validity, reliability, and feasibility of measurement. Final QIs were selected from CIs using the modified RAND Corporation-University of California, Los Angeles appropriateness methodology. RESULTS: Fifteen CIs were identified after literature review. After the first round of evaluations, the panel agreed on 11 candidate indicators as appropriate QIs with 2 additional CIs suggested for consideration. An expert panel meeting provided a platform to discuss areas of disagreement before final evaluations. The expert panel subsequently agreed upon 11 final QIs as appropriate measures of high-quality care for SSNHL. CONCLUSION: The 11 proposed QIs from this study are supported by evidence and expert consensus, facilitating measurement across a wide breadth of quality domains. With the recently updated SSNHL guidelines, and a greater focus on quality improvement opportunities, these QIs may be used by healthcare providers for targeted quality improvement initiatives.

Two-phase survey on the frequency of use and safety of MRI for hearing implant recipients.

PURPOSE: Magnetic resonance imaging (MRI) is often used to visualize and diagnose soft tissues. Hearing implant (HI) recipients are likely to require at least one MRI scan during their lifetime. However, the MRI scanner can interact with the implant magnet, resulting in complications for the HI recipient. This survey, which was conducted in two phases, aimed to evaluate the safety and performance of MRI scans for individuals with a HI manufactured by MED-EL (MED-EL GmbH, Innsbruck, Austria). METHODS: A survey was developed and distributed in two phases to HEARRING clinics to obtain information about the use of MRI for recipients of MED-EL devices. Phase 1 focused on how often MRI is used in diagnostic imaging of the head region of the cochlear implant (CI) recipients. Phase 2 collected safety information about MRI scans performed on HI recipients. RESULTS: 106 of the 126 MRI scans reported in this survey were performed at a field strength of 1.5 T, on HI recipients who wore the SYNCHRONY CI or SYNCHRONY ABI. The head and spine were the most frequently imaged regions. 123 of the 126 scans were performed without any complications; two HI recipients experienced discomfort/pain. One recipient required reimplantation after an MRI was performed using a scanner that had not been approved for that implant. There was only one case that required surgical removal of the implant to reduce the imaging artefact. CONCLUSION: Individuals with either a SYNCHRONY CI or SYNCHRONY ABI from MED-EL can safely undergo a 1.5 T MRI when it is performed according to the manufacturer's safety policies and procedures.

Active Transcutaneous Bone Conduction Implant: Audiometric Outcomes Following a Novel Middle Fossa Approach With Self-Drilling Screws.

OBJECTIVE: To present surgical and audiometric outcomes of patients implanted with an active transcutaneous bone conduction implant following the novel middle fossa surgical approach with self-drilling screws. STUDY DESIGN: Retrospective review. SETTING: Tertiary care center. PATIENTS: Thirty-seven adults with either conductive or mixed hearing loss that met indications for an active transcutaneous bone conduction implant were consecutively implanted from April, 2013 to May, 2018. INTERVENTION: Unilateral middle fossa implantation of an active transcutaneous bone conduction implant. MAIN OUTCOME MEASURES: Patient charts were reviewed for surgical outcomes and complications over the 6-year period. Preoperative air conduction, preoperative bone conduction, and 3-month postoperative aided thresholds were recorded. Speech perception was assessed using CNC words and AzBio sentences. Pure-tone averages (PTAs; measured at 0.5, 1.0, 2.0 and 3.0 kHz), air-bone gap, and functional gain were calculated. RESULTS: Mean air conduction and bone conduction PTAs (±standard deviation) of the implanted ear were 66.8 dB (±14.9 dB) and 21.9 dB (±14.0 dB), respectively. Mean aided PTA was 26.5 dB (± 8.5 dB). The average functional gain was 40.3 dB (±19.0 dB). Favorable speech perception outcomes were observed. No complications or instances of revision surgery were reported, with a mean follow-up time of 32 months (range, 9-71 mo). CONCLUSIONS: This is the first paper to describe outcomes of patients implanted with an active transcutaneous bone conduction implant via the middle fossa with self-drilling screws. Favorable surgical outcomes were observed with a follow-up of up to 6 years.

Cochlear implant failures and reimplantation: A 30-year analysis and literature review.

OBJECTIVES/HYPOTHESIS: The objectives of the study were to present an institutional experience with device failures and cochlear reimplantation rates over a 30-year period and to perform a detailed literature review. STUDY DESIGN: Retrospective institutional experience and literature review. METHODS: A review of cochlear implant failures over a period of 30 years, between January 1988 and March 2017, at a single institution was conducted. Cochlear implant failures were calculated based on manufacturer, type of failure, and overall failure rate. Survival analysis was performed using Kaplan-Meier curves. An electronic search of the PubMed, Web of Science, and EMBASE databases revealed 24 articles on the topic of cochlear device failure. Data on reimplantation and device failure rates were extracted from this literature review and analyzed. RESULTS: A total of 804 cochlear implantations were reviewed from three manufacturers. The institutional reimplantation rate was 2.9% compared to the pooled rate of 6.0% calculated from the literature review. Medical failures accounted for 0.5% of the overall failures, device failures accounted for 1.6%, and inconclusive failures account for 0.7%. Survival analysis revealed a significant difference among manufacturers. An improved device failure rate was noted in the adult population (0.8%) as compared to the pediatric population (2.8%). CONCLUSIONS: This 30-year review represents one of the longest series in the literature examining reimplantation, device failure, and medical failure rates. Cochlear implant survival varied by manufacturer and was significantly better in adult compared to pediatric patients. LEVEL OF EVIDENCE: NA Laryngoscope, 130:782-789, 2020.

Effects of Bimodal and Bilateral Cochlear Implant Use on a Nonauditory Working Memory Task: Reading Span Tests Over 2 Years Following Cochlear Implantation.

Purpose A growing body of evidence indicates that treatment of hearing loss by provision of hearing aids leads to improvements in auditory and visual working memory. The purpose of this study was to assess whether similar working memory benefits are observed following provision of cochlear implants (CIs). Method Fifteen adults with postlingually acquired severe bilateral sensorineural hearing loss completed the prospective longitudinal study. Participants were candidates for bilateral cochlear implantation with some aidable hearing in each ear. Implantation surgeries were carried out sequentially, approximately 1 year apart. Working memory was measured with the visual Reading Span Test (Daneman & Carpenter, 1980) at 5 time points: pre-operatively following a 6-month bilateral hearing aid trial, after 6 and 12 months of bimodal (CI plus contralateral hearing aid) listening experience following the 1st CI surgery and activation, and again after 6 and 12 months of bilateral CI listening experience following the 2nd CI surgery and activation. Results Compared to the preoperative baseline, CI listening experience yielded significant improvements in participants' ability to recall test words in the correct serial order after 12 months in the bimodal condition. Individual performance outcomes were variable, but almost all participants showed increases in task performance over the course of the study. Conclusions These results suggest that, similar to appropriate interventions with hearing aids, treatment of hearing loss with CIs can yield working memory benefits. A likely mechanism is the freeing of cognitive resources previously devoted to effortful listening.

Response to commentary on "the middle fossa approach with self-drilling screws: a novel technique for BONEBRIDGE implantation".

The aim of this letter is to respond to a commentary on a published article on the middle fossa approach to BONEBRIDGE implantation with self-drilling screws published by the senior authors.

Otology/Neurotology recommendations - Choosing Wisely campaign.

The Choosing Wisely Canada Campaign aims to raise awareness amongst physicians and patients regarding unnecessary tests and treatment. The otology/neurotology subspecialty group within the Canadian Society of Otolaryngology - Head & Neck Society developed a list of five common otologic presentations to help physicians deliver high quality effective care: (1) Don't order specialized audiometric and vestibular testing to screen for peripheral vestibular disease, (2) Don't perform computed tomography or blood work in the evaluation of sudden sensorineural hearing loss, (3) Don't perform auditory brain responses (ABR) in patients with asymmetrical hearing loss, (4) Don't prescribe oral antibiotics as first line treatment for patients with painless otorrhea associated with tympanic membrane perforation or tympanostomy tube, and (5) Don't perform particle repositioning maneuvers without a clinical diagnosis of posterior canal benign paroxysmal positional vertigo.

The middle fossa approach with self-drilling screws: a novel technique for BONEBRIDGE implantation.

BACKGROUND: Bone conduction implants can be used in the treatment of conductive or mixed hearing loss. The BONEBRIDGE bone conduction implant (BB-BCI) is an active, transcutaneous device. BB-BCI implantation can be performed through either the transmastoid or retrosigmoid approach with their respective limitations. Here, we present a third, novel approach for BB-BCI implantation. OBJECTIVE: Describe the detailed surgical technique of BB-BCI implantation through a middle fossa approach with self-drilling screws and present preliminary audiometric outcome data following this approach. METHODS: A single institution, retrospective chart review was completed for patients implanted with the BB-BCI via the middle fossa approach. Preoperative planning and modelling were performed using 3D Slicer. Audiological testing was performed pre- and post-operatively following standard audiometric techniques. RESULTS: Forty patients underwent BB-BCI implantation using the middle fossa approach. Modelling techniques allowed for implantation through the use of external landmarks, obviating the need for intraoperative image guidance. The surgical technique was refined over time through experience and adaptation. Mean follow-up was 29 months (range 3-71 months) with no surgical complications, favourable cosmesis, and expected audiometric outcomes. An average functional gain of 39.6 dB (± 14.7 SD) was found. CONCLUSION: The middle fossa technique with self-drilling screws is a safe and effective option for BONEBRIDGE implantation. As a reference for other groups considering this approach, an annotated video has been included as a supplement to the study.

Stapedectomy Versus Stapedotomy.

Stapedectomy and stapedotomy represent the state-of-the-art surgical procedures in addressing the conductive hearing loss caused by otosclerosis. Their high rates of success and long-term stability have been demonstrated repeatedly in many studies. In comparing the short- and long-term results of the 2 procedures, it is evident that stapedotomy confers better hearing gain at high frequencies and lower complication rates. Modified stapes mobilization procedures may represent the next major development in stapes surgery in a selected patient population.

Hearing preservation cochlear implantation in children: The HEARRING Group consensus and practice guide.

OBJECTIVES: To provide multidisciplinary cochlear implant teams with a current consensus statement to support hearing preservation cochlear implantation (HPCI) in children, including those children with symptomatic partial deafness (PD) where the intention is to use electric-acoustic stimulation (EAS). The main objectives are to provide guidelines on who is a candidate, how to assess these children and when to implant if Med-El Flex electrode arrays are chosen for implantation. METHODS: The HEARRING group reviewed the current evidence and practice regarding the management of children to be considered for HPCI surgery emphasizing the assessment needed prior to implantation in order to demonstrate the benefits in these children over time. The consensus statement addresses following three key questions: (1) Should these children be treated? (2) How to identify these children? (3) How to manage these children? SUMMARY: The HEARRING group concludes that irrespective of the degree of residual hearing present, the concepts of hearing and structure preservation should be applied in every child undergoing cochlear implantation and that HPCI is a safe and reliable treatment option. Early detection and multidisciplinary assessment are key to the identification of children with symptomatic PD, these children should undergo HPCI as early as possible.

Otoconia and otolithic membrane fragments within the posterior semicircular canal in benign paroxysmal positional vertigo.

OBJECTIVES/HYPOTHESIS: Benign paroxysmal positional vertigo (BPPV) is the most common vestibular disorder with an incidence between 10.7 and 17.3 per 100,000 persons per year. The mechanism for BPPV has been postulated to involve displaced otoconia resulting in canalithiasis. Although particulate matter has been observed in the endolymph of affected patients undergoing posterior canal occlusion surgery, an otoconial origin for the disease is still questioned. STUDY DESIGN: In this study, particulate matter was extracted from the posterior semicircular canal of two patients and examined with scanning electron microscopy. METHODS: The samples were obtained from two patients intraoperatively during posterior semicircular canal occlusion. The particles were fixed, stored in ethanol, and chemically dehydrated. The samples were sputter coated and viewed under a scanning electron microscope. Digital images were obtained. RESULTS: Intact and degenerating otoconia with and without linking filaments were found attached to amorphous particulate matter. Many otoconia appeared to be partially embedded in a gel matrix, presumably that which encases and anchors the otoconia within the otolith membrane, whereas others stood alone with no attached filaments and matrix. The otoconia measured roughly 2 to 8 µm in length and displayed a uniform outer shape with a cylindrical bulbous body and a 3 + 3 rhombohedral plane at each end. CONCLUSIONS: These findings suggest that the source of the particulate matter in the semicircular canals of patients with BPPV is broken off fragments of the utricular otolithic membrane with attached and detached otoconia. LEVEL OF EVIDENCE: NA Laryngoscope, 127:709-714, 2017.

Quality standards for bone conduction implants.

CONCLUSION: Bone conduction implants are useful in patients with conductive and mixed hearing loss for whom conventional surgery or hearing aids are no longer an option. They may also be used in patients affected by single-sided deafness. OBJECTIVES: To establish a consensus on the quality standards required for centers willing to create a bone conduction implant program. METHOD: To ensure a consistently high level of service and to provide patients with the best possible solution the members of the HEARRING network have established a set of quality standards for bone conduction implants. These standards constitute a realistic minimum attainable by all implant clinics and should be employed alongside current best practice guidelines. RESULTS: Fifteen items are thoroughly analyzed. They include team structure, accommodation and clinical facilities, selection criteria, evaluation process, complete preoperative and surgical information, postoperative fitting and assessment, follow-up, device failure, clinical management, transfer of care and patient complaints.

Pentoxifylline-tocopherol-clodronate combination: A novel treatment for osteoradionecrosis of the temporal bone.

BACKGROUND: Osteoradionecrosis (ORN) of the temporal bone is a complication of radiation therapy that is extremely challenging to manage. METHODS: We report the case of a patient treated at our institution and present a review of the literature. RESULTS: A 52-year-old woman presented with ORN of the temporal bone 20 years after radiation therapy for an ipsilateral parotid tumor. She failed conservative management, including serial debridements, oral and topical antibiotics/antifungals, and aural lavage. As an alternative to hyperbaric oxygen (HBO) and/or temporal bone resection, treatment with pentoxifylline-tocopherol-clodronate combination (PENTOCLO) was pursued and her condition improved dramatically. CONCLUSION: This is the first document use of PENTOCLO to treat ORN of the temporal bone. PENTOCLO may represent an effective nonsurgical management option for ORN of the temporal bone.

Round window reinforcement for superior semicircular canal dehiscence: a retrospective multi-center case series.

PURPOSE: To evaluate the outcome of round window (RW) tissue reinforcement in the management of superior semicircular canal dehiscence (SSCD). MATERIALS AND METHODS: Twenty-two patients with confirmed diagnosis of SSCD by clinical presentation, imaging, and/or testing were included in the study. Six surgeons at four institutions conducted a multicenter chart review of patients treated for symptomatic superior canal dehiscence using RW tissue reinforcement or complete RW occlusion. A transcanal approach was used to reinforce the RW with various types of tissue. Patients completed a novel postoperative survey, grading preoperative and postoperative symptom severity. RESULTS: Analysis revealed statistically significant improvement in all symptoms with the exception of hearing loss in 19 patients who underwent RW reinforcement. In contrast, 2 of 3 participants who underwent the alternate treatment of RW niche occlusion experienced worsened symptoms requiring revision surgery. CONCLUSION: RW tissue reinforcement may reduce the symptoms associated with SSCD. The reinforcement technique may benefit SSCD patients by reducing the "third window" effect created by a dehiscent semicircular canal. Given its low risks compared to middle cranial fossa or transmastoid canal occlusion, RW reinforcement may prove to be a suitable initial procedure for intractable SSCD. In contrast, complete RW occlusion is not advised.

Cisplatin otoprotection using transtympanic L-N-acetylcysteine: a pilot randomized study in head and neck cancer patients.

OBJECTIVES/HYPOTHESIS: To evaluate the feasibility and efficacy of transtympanic L-N-Acetylcysteine (L-NAC) administration in patients receiving cisplatin chemotherapy for head and neck cancer. STUDY DESIGN: Prospective randomized nonblinded open-label clinical trial. METHODS: Transtympanic 2% L-NAC was administered to one randomly selected ear with the other ear as control in each patient. Primary outcome parameter was the difference in the loss of pure tone averages (PTA) at 2, 4, and 8 kHz between the L-NAC and control ear at 1 to 2 months following chemotherapy. RESULTS: Eleven patients completed the study, with two patients demonstrating significantly better hearing in the L-NAC treated ear (18.2%). However, for the overall group, the difference in hearing preservation did not reach significance. Two percent L-NAC administration was well tolerated in this patient population. There were no adverse effects associated with L-NAC. CONCLUSION: Although the study did not demonstrate a significant benefit overall, transtympanic L-NAC was associated with significantly better hearing in two patients. Better delivery methods may improve the efficacy of this treatment. L-NAC remains a promising drug in preventing cisplatin-induced ototoxicity.

Endolymphatic sac surgery versus intratympanic gentamicin for the treatment of intractable Ménière's disease: a retrospective review with survey.

OBJECTIVES: 1) To review a 10-year experience of endolymphatic sac surgery (ESS) and intratympanic gentamicin (ITG) for intractable Ménière's disease (MD), and 2) to compare preoperative and postoperative outcomes. DESIGN: Retrospective chart review and survey. SETTING: Tertiary care center. PATIENTS: Patients treated with ESS or ITG between 1997 and 2007 at London Health Sciences Centre were eligible for recruitment. INTERVENTIONS: ESS or ITG. MAIN OUTCOMES: 1) 1995 American Academy of Otolaryngology-Head and Neck Surgery hearing stage, vertigo class, and functional level; and 2) a 40-item validated quality-of-life questionnaire (MD Outcome Questionnaire). STATISTICAL ANALYSES: Chi-squared and t tests. RESULTS: Sixty-seven patients were recruited (n = 30 ESS; n = 37 ITG). Preoperatively, the ITG group had poorer hearing stage (p = 0.03). There were no differences between groups on preoperative functional level and QOL measures. Postoperatively, ESS patients reported more tinnitus (p = 0.003) and aural fullness (p = 0.01). There were no differences in posttreatment vertigo class. Secondary treatment was required for 27% of patients in the ESS compared with 3% in the ITG. Posttreatment hearing remained unchanged for the ITG and was overall decreased in the ESS group (p = 0.03). Participants in the ITG reported better postoperative functional levels (p = 0.02) and higher global (p = 0.04), social (p = 0.001), and overall QOL scores (p = 0.03). CONCLUSION: ITG, compared with ESS, reveals better posttreatment functional levels, and superior global, social, and overall QOL scores. Although no statistical difference in vertigo class, a clinical difference is observed.

Recent advances in viral inner ear disorders.

PURPOSE OF REVIEW: To highlight the recent advances in the understanding of the diagnosis and management of viral inner ear disorders. Congenital sensorineural hearing loss (cSNHL), sudden sensorineural hearing loss (SSNHL), Ménière's disease, and vestibular neuritis/viral labyrinthitis are discussed. RECENT FINDINGS: Cytomegalovirus infection during pregnancy is an under-recognized cause of hearing loss and central nervous system disease amongst the general population. Prevention of maternal infection and treatment of affected newborns with ganciclovir are promising interventions. Recent evidence in SSNHL patients has resulted in recommendations against viral serology or the use of antivirals. There appears to be an increased risk of SSNHL in patients with comorbid hypertension and diabetes. The viral hypothesis of Ménière's disease remains unproven. In patients with an acute episode of vestibular neuritis, there is presently not sufficient evidence to support the routine use of corticosteroids or antiviral medications. SUMMARY: cSNHL remains the most clearly defined of the viral inner ear disorders. The evidence for viral involvement in SSNHL, Ménière's disease, and vestibular neuritis is indirect and equivocal. This review highlights the recent advancements in the diagnosis and management of these disorders.