Nerve guide conduits, nerve transfers, and local and free muscle transfer in facial nerve palsy.

PURPOSE OF REVIEW: To highlight the recent literature on reinnervation options in the management of facial nerve paralysis using nerve conduits, and nerve and muscle transfers. RECENT FINDINGS: Engineering of natural and synthetic nerve conduits has progressed and many of these products are now available on the market. The use of the masseter nerve has become more popular recently as a choice in nerve transfer procedures due to various unique advantages. Various authors have recently described mimetic muscle reinnervation using more than one nerve transfer, as well as dual and triple innervation of free muscle transfer. SUMMARY: The ideal nerve conduit continues to be elusive, however significant progress has been made with many natural and synthetic materials and designs tested and introduced on the market. Many authors have modified the classic approaches in motor nerve transfer, as well as local and free muscle transfer, and described new ones, that aim to combine their advantages, particularly the simplification to a single stage and use of multiple reinnervation to the mimetic muscles. These advances are valuable to the reconstructive surgeon as powerful tools that can be tailored to the unique challenges of patients with facial nerve palsy looking for dynamic reanimation options.

Geometrically accurate real-time volumetric visualization of the middle ear using optical coherence tomography.

We introduce a novel system for geometrically accurate, continuous, live, volumetric middle ear optical coherence tomography imaging over a 10.9mm×30∘×30∘ field of view (FOV) from a handheld imaging probe. The system employs a discretized spiral scanning (DC-SC) pattern to rapidly collect volumetric data and applies real-time scan conversion and lateral angular distortion correction to reduce geometric inaccuracies to below the system's lateral resolution over 92% of the FOV. We validate the geometric accuracy of the resulting images through comparison with co-registered micro-computed tomography (micro-CT) volumes of a phantom target and a cadaveric middle ear. The system's real-time volumetric imaging capabilities are assessed by imaging the ear of a healthy subject while performing dynamic pressurization of the middle ear in a Valsalva maneuver.

Comparison of passive versus active transcutaneous bone anchored hearing devices in the pediatric population.

OBJECTIVE: Transcutaneous bone anchored hearing devices (BAHDs) were introduced in an effort to avoid potential complications associated with the abutment of percutaneous BAHDs. Transcutaneous BAHDs can be active or passive. While studies have demonstrated good outcomes with both, a direct comparison of audiological and clinical outcomes of these devices in the pediatric population has not yet been studied. STUDY DESIGN: Retrospective, multicenter study. SETTING: Two tertiary academic centers. METHODS: Between 2015 and 2019, all patients who received an active transcutaneous BAHD (Bonebridge, BB) at one center, and patients that received a passive transcutaneous BAHD (Attract, AT) at another center, were included in this study. Exclusion criteria included age > 18 years, and mixed hearing loss or single-sided deafness. Study outcomes included patient demographics, indications, complications and preoperative and one-year postoperative audiometric data. RESULTS: Eighteen BB and eight AT patients met the inclusion criteria. The age range was 5-16 years. There were no significant differences in complication outcomes. Both devices demonstrated similar mean improvements in hearing thresholds at frequencies of 250 Hz (38 dB Active vs. 38 dB Passive), 500 Hz (34 dB vs. 42 dB), 1000 Hz (34 dB vs. 40 dB) and 2000 Hz (31 dB vs. 22 dB). The BB was significantly more effective at frequencies of 4000 Hz (28 dB vs. 7 dB) and 8000 Hz (29 dB vs. 6 dB) (p < 0.05). CONCLUSION: This is the first study comparing audiological outcomes between an active and a passive transcutaneous BAHD in the pediatric population. While both devices improved audiometric outcomes in the low and mid frequencies, the active BAHD demonstrated significantly better outcomes in the higher frequencies.

Transtympanic Visualization of Cochlear Implant Placement With Optical Coherence Tomography: A Pilot Study.

OBJECTIVE: This study aimed to evaluate the ability of transtympanic middle ear optical coherence tomography (ME-OCT) to assess placement of cochlear implants (CIs) in situ. PATIENT: A 72-year-old man with bilateral progressive heredodegenerative sensorineural hearing loss due to work-related noise exposure received a CI with a slim modiolar electrode for his right ear 3 months before his scheduled checkup. INTERVENTION: A custom-built swept source ME-OCT system (λo = 1550 nm, ∆λ = 40 nm) designed for transtympanic middle ear imaging was used to capture a series of two- and three-dimensional images of the patient's CI in situ. Separately, transtympanic OCT two-dimensional video imaging and three-dimensional imaging were used to visualize insertion and removal of a CI with a slim modiolar electrode in a human cadaveric temporal bone through a posterior tympanotomy. MAIN OUTCOME MEASURE: Images and video were analyzed qualitatively to determine the visibility of implant features under ME-OCT imaging and quantitatively to determine insertion depth of the CI. RESULTS: After implantation, the CI electrode could be readily visualized in the round window niche under transtympanic ME-OCT in both the patient and the temporal bone. In both cases, characteristic design features of the slim modiolar electrode allowed us to quantify the insertion depth from our images. CONCLUSIONS: ME-OCT could potentially be used in a clinic as a noninvasive, nonionizing means to confirm implant placement. This study shows that features of the CI electrode visible under ME-OCT can be used to quantify insertion depth in the postoperative ear.

Robotics and cochlear implant surgery: goals and developments.

PURPOSE OF REVIEW: Cochlear implantation (CI) is a viable option for patients with severe sensorineural hearing loss. Advances in CI have focused on minimizing cochlear trauma to improve hearing preservation outcomes, and in doing so expanding candidacy to patients with useful cochlear reserve. Robotics holds promise as a potential tool to minimize intracochlear trauma with electrode insertion, improve surgical efficiency, and reduce surgical complications. The purpose of this review is to summarize efforts and advances in the field of robotic-assisted CI. RECENT FINDINGS: Work on robotics and CI over the past few decades has explored distinct surgical aspects, including image-based surgical planning and intraoperative guidance, minimally invasive robotic-assisted approaches mainly through percutaneous keyhole direct cochlear access, robotic electrode insertion systems, robotic manipulators, and drilling feedback control through end effector sensors. Feasibility and safety have been established and many devices are undergoing clinical trials for clinical adoption, with some having already achieved approval of national licensing bodies. SUMMARY: Significant work has been done over the past two decades that has shown robotic-assisted CI to be feasible and safe. Wider clinical adoption can potentially result in improved hearing preservation and quality of life outcomes to more CI candidates.

Long-Term Audiometric Outcomes of a Self-Crimping Stapes Prosthesis With CO 2 Laser Stapedotomy.

OBJECTIVE: To evaluate our experience with a self-crimping stapes prosthesis. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: All patients diagnosed with otosclerosis who underwent surgery between June 2013 and June 2020. Inclusion criteria were 18 years or older, isolated stapes ankylosis, and at least 1 year of postoperative audiologic data. INTERVENTIONS: CO 2 laser stapedotomy undertaken by the same surgeon using the same CO 2 laser stapedotomy technique and the same prosthesis. MAIN OUTCOME MEASURES: Preoperative and postoperative audiologic data including air-bone gap (ABG) measurements, average speech discrimination score and pure-tone averages (PTAs). Postoperative hearing assessments were performed at 3 weeks, 3 months, 6 months, 1 year, and annually thereafter. RESULTS: Two hundred fourteen patients were included in the study, of whom 17 had bilateral sequential surgery for a total of 231 ears. Mean preoperative air conduction-PTA was 58.8 dB and mean preoperative bone conduction-PTA 24.2 dB, a preoperative ABG of 34.6 dB. One year postoperatively, mean air conduction-PTA improved to 31.2 dB ( p < 0.0001). ABG showed a significant improvement from 34.6 to 5.5 dB ( p < 0.0001). Closure of the ABG to within 10 dB was achieved in 87% ears at 3 months, in 91% at 6 months, and in 93% at 1 year. There was no significant difference in preoperative and postoperative average speech discrimination score. CONCLUSION: The current study demonstrates favorable audiologic outcomes in a large cohort of patients using a self-crimping stapes prosthesis. These results were stable for up to 7 years on follow-up.

Single-Center Experience Evaluating Clinical Outcomes of a Novel-Guided Drill System for Percutaneous Bone-Anchored Hearing Implant.

OBJECTIVE: Evaluate intraoperative and postoperative outcomes of a novel guided drill system for percutaneous bone-anchored hearing implants. METHODS: Between January 2016 and February 2021, patients age ≥18 years deemed potential candidates for a bone-anchored hearing device, were formally assessed for candidacy and counseling. Those that qualified and opted to proceed were added to a prospectively maintained database, including demographic, clinical, and audiologic data. Intraoperative findings were reported, as were clinical outcomes at 7 days, 4 weeks, 3 months and 6 months postoperatively. The Holgers index was used to grade soft tissue reactions. RESULTS: One hundred patients underwent the procedure. There were 56 women, and mean age was 54 years (18-84 yr). Ninety-six were done under local anesthetic. Mean surgical time was 13 minutes (9-27 min). No significant intraoperative events were noted. There were nine cases of implant loss, all in the first 50 cases. Mean duration of implant loss was 3.6 weeks (range, 2-5 wk). At the first postoperative visit, 82 had Holgers 0, 16 Holgers 1, 2 Holgers 2, and none Holgers 3. At the second postoperative visit, excluding the 9 with implant loss, 83 (91%) had Holgers 0, 6 (7%) Holgers 1, and 2 (2%) Holgers 2. None were Holgers 3. CONCLUSIONS: The current study represents, to our knowledge, the largest series on the novel guided drill technique. Results show it is safe and efficient with low soft tissue complication rates. Drill bit design and technical modifications may have helped lower implant loss rate in this series over time.

Active Versus Passive Transcutaneous Bone Conduction Hearing Devices: A Systematic Review and Meta-Analysis.

OBJECTIVES: Active and passive transcutaneous devices (tBCHDs) have been introduced in an effort to address complication concerns with percutaneous devices. Direct comparison of active and passive devices through evidence synthesis practices is incomplete. This systematic review and meta-analysis sought to synthesize and compare available evidence on audiological, quality of life, and complication-related outcomes of active and passive tBCHDs. DESIGN: MEDLINE, EMBASE, CINAHL, and Cochrane CENTRAL were searched from inception to September 23, 2019. Observational and experimental studies investigating active or passive tBCHDs in adults were eligible. Studies were screened independently in duplicate. This study is reported in accordance with the PRISMA guidelines. Risk of bias and quality assessments were completed using the Newcastle-Ottawa Scale and the Quality Appraisal Tool for Case Series. Meta-analysis was performed with random-effects models. Audiological outcomes included changes in pure-tone average, functional hearing, and high-frequency hearing. Quality of life outcomes included patient-reported results. Complications included minor, major, and total complications experienced. RESULTS: One thousand five hundred forty-two nonduplicate articles were screened. Twenty-eight studies were included. Quality of included studies was low overall. The pooled complication rate for active devices was 14.8% (95% confidence interval: 0.09-0.21, I2: 0%). The pooled improvement in functional hearing for active devices among those with mixed or conductive hearing loss was 31.8 dB (95% confidence interval: 27.7-35.9, I2: 44.6). Improvement in functional hearing ranged from 25.2 to 44.3 dB for passive devices. Active devices provided improved high-frequency hearing compared to passive devices: the weighted average hearing gains at 2, 3, 4, and 6 kHz were 26.5, 25.7, 31.8, and 34.3 dB for active devices and 26.2, 21.1, 16.8, and 6.4 dB for passive devices, respectively. Both device types demonstrated improvement in ease of communication, reverberation, and understandability in background noise. CONCLUSIONS: Both active and passive tBCHDs demonstrate acceptable safety profiles and QoL improvements. Active devices may provide better hearing outcomes, especially in high frequencies, but high-quality comparative studies are lacking. Future work is needed in this regard.

Emerging artificial intelligence applications in otological imaging.

PURPOSE OF REVIEW: To highlight the recent literature on artificial intelligence (AI) pertaining to otological imaging and to discuss future directions, obstacles and opportunities. RECENT FINDINGS: The main themes in the recent literature centre around automated otoscopic image diagnosis and automated image segmentation for application in virtual reality surgical simulation and planning. Other applications that have been studied include identification of tinnitus MRI biomarkers, facial palsy analysis, intraoperative augmented reality systems, vertigo diagnosis and endolymphatic hydrops ratio calculation in Meniere's disease. Studies are presently at a preclinical, proof-of-concept stage. SUMMARY: The recent literature on AI in otological imaging is promising and demonstrates the future potential of this technology in automating certain imaging tasks in a healthcare environment of ever-increasing demand and workload. Some studies have shown equivalence or superiority of the algorithm over physicians, albeit in narrowly defined realms. Future challenges in developing this technology include the compilation of large high quality annotated datasets, fostering strong collaborations between the health and technology sectors, testing the technology within real-world clinical pathways and bolstering trust among patients and physicians in this new method of delivering healthcare.

Clinical efficiency and safety of the oticon medical neuro cochlear implant system: a multicenter prospective longitudinal study.

OBJECTIVE: This prospective longitudinal cohort study at six tertiary referral centers in Canada and Denmark describes the clinical efficiency and surgical safety of cochlear implantation with the Oticon Medical Neuro cochlear implant system, including the Neuro Zti implant, the EVO electrode array, and the Neuro One sound processor. METHODS: Patients were adult cochlear implant candidates with bilateral sensorineural hearing loss. RESULTS: The mean HINT scores in quiet pre-operatively and at 3, 6, and 12 months post-activation were 13%, 58%, 67%, and 72%, respectively, and in noise (+10 dB SNR) 13%, 46%, 53%, and 59%, respectively. The mean improvement from baseline to 6 months post-activation was 54% in quiet and 40% in noise. The surgical major complication incidence rate was 0% and the post-surgical major complication incidence rate (until 12 months post-activation) was 4%. There was no adverse event that was fatal, that required explantation, or that resulted in sound processor nonuse, and no implant failure. CONCLUSION: Cochlear implantation with the Oticon Medical Neuro system enables speech identification both in quiet and in noise and audiologic outcomes continue to improve in the year following activation. No substantial adverse events occurred during the surgical implantation procedure and during the 12 months post-activation.

Treatment of patients with glomus jugulare tumours (GJT) and its subjective effect on quality of life (QoL) measures.

Cerebellopontine angle (CPA) tumours account for 6-10% of intracranial tumours. The most common CPA tumours are vestibular schwannomas (VS), also known as acoustic neuromas, benign tumours of the vestibulocochlear nerve. Less common but symptomatic skull base lesions are glomus jugulare tumours (GJT), of which approximately 40% are identified as CPA tumours. Initial symptoms for GJT may include hearing loss and tinnitus and progress to various cranial nerve dysfunctions. Three well-accepted treatment modalities for such tumours include surgical resection, radiotherapy and/or conservative management employing serial MR or CT imaging. Patients' quality of life may be impacted by different treatment methods, so treatment decisions should be client centered.

Clinical and audiometric outcomes of palisade cartilage myringoplasty under local anesthetic in an office setting.

OBJECTIVE: Assess clinical and functional outcomes of a modified palisade cartilage-perichondrium graft myringoplasty under local in an office setting. STUDY DESIGN: Retrospective case series. SETTING: Tertiary care facility. PATIENTS: Patients with a tympanic membrane perforation presenting between March 2013 and October 2017. Inclusion criteria included age ≥ 7 years, entire perforation margin visualized through a transcanal view, and the ability to lie supine for up to 45 min. Exclusion criteria included a conductive hearing loss larger than expected, and presence of active infection. INTERVENTION: In-office modified myringoplasty technique under local anesthesia without sedation. MAIN OUTCOME MEASURES: Complete perforation closure rate and audiometric outcomes. RESULTS: 250 patients underwent the procedure, of whom 13 had bilateral sequential procedures (total 263 ears). Of those, 197 were primary and 66 revision. Average age was 46.3 years. Perforation sizes were categorized as small (32), moderate (109), large (78), and subtotal (44). Complete perforation closure was evident in 219 of the 250 cases (88%). Preoperative mean air pure tone average (PTA) was 56.7 dB and mean bone PTA was 27.5 dB (pre-operative ABG 29.2 dB). AC-PTA significantly improved to 35.0 dB (p < 0.0001), and ABG to 9.6 dB (p < 0.0001). Only subtotal perforations showed a statistically significant negative relationship with outcome (p = 0.04). CONCLUSION: The modified palisade cartilage-perichondrium graft myringoplasty under local anesthetic is a highly successful procedure well tolerated by adult and pediatric patients with variable perforation sizes. This may have significant potential patient benefits, as well as cost savings to the health care system.

Pilot Study Assessing the Feasibility and Clinical Outcomes of Office-Based Ossiculoplasty.

OBJECTIVES:: The aim of this study was to assess the feasibility and safety of ossiculoplasty under local anesthesia in an office setting without sedation. METHODS:: Between May 2017 and November 2017, patients who presented with conductive hearing loss and known isolated ossicular discontinuities were offered ossiculoplasty under local anesthesia. Inclusion criteria included age ⩾ 18 years, adequate transcanal access, and the ability to lie supine for up to 45 minutes. Exclusion criteria included associated tympanic membrane perforation and the presence of middleear or mastoid cholesteatoma or infection. RESULTS:: Fourteen patients underwent the procedure. The mean age was 48.3 years (range, 19-74 years). Six were primary and 8 revision cases. There were 8 partial and 6 total prosthesis placements. The mean operative time was 34 minutes (range, 26-43 minutes). All patients tolerated the procedure to completion. There were no intraoperative complications. The mean air conduction pure-tone average was 76.6 dB and the mean bone conduction pure-tone average was 27.2 dB, with a preoperative air-bone gap of 49.9 dB. Air conduction pure-tone average significantly improved to 45.2 dB ( P < .0001). Air-bone gap significantly improved to 17.8 dB ( P < .0001). CONCLUSIONS:: Ossiculoplasty using partial or total prostheses can be safely performed in the office setting under local anesthesia without sedation in carefully selected patients. This has potentially significant patient and system benefits.

Quality of life related to symptomatic outcomes in patients with vestibular schwannomas: A Canadian Centre perspective.

Patients with vestibular schwannomas (VS) typically present with hearing loss and tinnitus as well as variable cranial nerve dysfunctions. Surgical resection, stereotactic radiotherapy and/or conservative management employing serial magnetic resonance or computed tomography imaging serve as the main treatment options. Quality of life (QoL) may be impacted by the extent of tumour burden and exacerbated or relieved by treatment. Subjective assessment and quality of life inventories provide valuable information in client centered approaches with important implications for treatment. The intention of QoL measurements affecting VS patients within a clinical setting is to facilitate discussions regarding treatment options and objectively evaluate patient- centered clinical outcomes in a naturalistic setting.

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.

The challenges of starting a cochlear implant programme in a developing country.

PURPOSE OF REVIEW: Deafness is indeed a silent disability in many parts of the world, and the majority of people who have hearing impairment live in developing countries. With rising economy and developing nations becoming hub of industrialization, hearing loss may increase in these countries. In this review, the authors have elected to focus the discussion on India to frame the challenges of cochlear implants in a developing country. This article reviews the common causes of hearing loss, the challenges faced by those with hearing impairment and why the penetration of these devices is low and also reviews some reasons for the inability of the government to support the implant programme in India. RECENT FINDINGS: Early identification of hearing is crucial towards ensuring appropriate hearing rehabilitation; it is, however, challenged by various factors, including public awareness, absence of a national new born screening programme, accessibility to diagnostic centres, availability of trained personnel and equipment and patient affordability. Cochlear implants are a proven auditory rehabilitative option for individuals with severe to profound sensorineural hearing loss, who otherwise do not benefiting from hearing aids. Nevertheless, only a small percentage of these individuals receive cochlear implants, and cost remains a leading prohibitive factor, particularly in developing countries. For example, in India, the personal average annual income is well below US $2000, whereas these devices cost between $12,000 and $25,000, exclusive of hospital and staff fees. Hence, the technology is virtually unavailable to the masses. SUMMARY: To overcome the cost limitation of those who would benefit from cochlear implants countries such as India and China have started to develop their own indigenous implants.

Intravascular papillary endothelial hyperplasia of the internal auditory canal.

Intravascular papillary endothelial hyperplasia (IPEH), also known as Masson's tumor, is a rare vascular lesion characterized by intravascular proliferation of endothelial-lined papillae and a propensity for manifestation in the head and neck. Signs and symptoms associated with IPEH generally occur due to compressive effects of the lesion on adjacent structures. A rare instance of IPEH occurring in the internal auditory canal is presented herein. Clinical presentation, radiographic and pathologic findings, and management strategies are discussed.