Changing Management of Intravestibular Schwannomas in the Era of Cochlear Implantation for Single-Sided Deafness.

OBJECTIVE: Intralabyrinthine schwannomas (ILSs) are a rare cause of deafness. Patients with ILS confined to the semicircular canals and the vestibule (intravestibular schwannomas) are potential candidates for cochlear implantation for hearing rehabilitation, a new option for patients with unilateral hearing loss since the 2019 FDA approval of cochlear implant (CI) for single-sided deafness. In this report, we describe an evolving management approach for ILSs causing hearing loss. PATIENTS: Adults (≥18 years) who underwent simultaneous ILS resection and CI between January 2019 and June 2023 (n = 3). INTERVENTION: Transmastoid labyrinthectomy with simultaneous cochlear implantation. MAIN OUTCOME MEASURES: Hearing performance with cochlear implantation measured as CNC Word Recognition scores and AzBio Sentence scores. RESULTS: Three patients with ILS confined to the semicircular canals and vestibule underwent simultaneous tumor resection via labyrinthectomy with CI placement. In all cases, complete tumor resection and full CI insertion were achieved. No patients experienced postoperative complications. Patients 1 and 2 underwent 6- and 9-month postactivation testing, respectively, with CNC scores 64% to 80% and AzBio 81% to 99% in the implanted ears. Patient 3 scored 0% on CNC and AzBio testing at 3 months and deferred her 6-month audiometry. CONCLUSIONS: Patients with ILS confined to the vestibule and semicircular canals can be considered for simultaneous tumor resection and CI placement.

Role of the otologist/neurotologist in managing auricular and periauricular cutaneous malignancies: A 10-year otologic oncology experience.

Objective: Auricular/periauricular cutaneous malignancies can be challenging to manage surgically due to the complex anatomy of the region. Otologists/neurotologists have unique skillsets that are well-suited to surgically treat these patients. We aim to highlight the role of otologists and neurotologists in providing surgical care of patients with auricular and periauricular malignancies by describing the experience of a single fellowship-trained neurotologist over a 10-year period. Methods: Retrospective chart review of 387 patients with auricular and periauricular malignancy treated by a single neurotologist between 2012 and 2022 was completed. Tumor histology and procedures performed for each patient were extracted. Additional data was collected for a subset of 84 patients with complex cases requiring selective neck dissection, parotidectomy, lateral temporal bone resection, regional advancement or rotational flap reconstruction, and/or free tissue transfer reconstruction. Results: Within the series of 387 patients, squamous cell carcinoma was the most common histology (42.6%, n = 165), followed by basal cell carcinoma (40.8%, n = 158), and melanoma (9.8%, n = 38). Common surgical procedures included wide local excision (61.8%, n = 239), partial/sub-total auriculectomy 18.3% (n = 71), or total auriculectomy 5.2% (n = 20). Within the 84-patient subset, median age at diagnosis was 71.9 years. Dermatologists provided most patient referrals (50.0%, n = 42). Most common tumor locations included: auricular (58.3%, n = 49), pre-auricular (21.4%, n = 18), and parotid (27.4%, n = 23). Revision surgery occurred in 22.6% of cases (n = 19), of which 26.3% (n = 5) for positive margins and 31.6% (n = 6) for recurrence. Mean follow-up was 22.8 months. Disease-specific 5-year survival was 91%. Conclusions: We demonstrate the feasibility of an otologist/neurotologist incorporating the surgical management of auricular and periauricular malignancies into their practice. Level of Evidence: 4.

Reversing Synchronized Brain Circuits Using Targeted Auditory-Somatosensory Stimulation to Treat Phantom Percepts: A Randomized Clinical Trial.

Importance: Animal models have shown altered dorsal cochlear nucleus circuitry in animals that develop tinnitus; however, precise treatment using bisensory (auditory and somatosensory) stimuli can reverse altered neural patterns and lessen tinnitus. Objective: To confirm and extend the findings of a pilot study, which suggested an increased efficacy of bisensory stimulation, to a clinical trial with a greater duration and greater number of participants. Design, Setting, and Participants: This double-blind, crossover, single-center randomized clinical trial was conducted from March 2019, with a 3-month follow-up per participant ending in July 2022. Eligible adults were recruited from the University of Michigan Health System in Ann Arbor, Michigan. Eligibility criteria included bothersome tinnitus (Tinnitus Functional Index [TFI] score, ≥17 points), somatic tinnitus, normal to moderate hearing loss, and no other tinnitus treatments in the 6 months prior to the trial. Included participants were randomized to either treatment group 1, which received active (bisensory) treatment, or group 2, which received the control (auditory-only) treatment. Results were analyzed using intent-to-treat (ITT) and per protocol (PP) populations. Intervention: Precisely timed bisensory (combined auditory and somatosensory) treatment was delivered through a portable, custom, take-home device that was provided to each participant for daily, at-home treatments. Group 1 participants received 30 minutes per day of the bisensory treatment for 6 weeks, followed by a 6-week washout phase, and then 30 minutes per day of the auditory-only treatment followed by a second 6-week washout phase. Group 2 participants received the auditory-only treatment first, followed by a washout phase, and then the bisensory treatment followed by a second washout phase. Main Outcomes and Measures: Primary end points were changes in TFI score and tinnitus loudness level from baseline through week 6 and week 12. Results: Of 337 screened individuals, 99 (mean [SD] age, 47 [12.7] years; 59 males [60%]; 85 with non-Hispanic White [86%] race and ethnicity) were enrolled into the study and randomized to treatment group 1 (n = 49) or group 2 (n = 50). The active but not the control treatment resulted in clinically significant decreases in TFI scores at week 6 of phase 1 (ITT population: -12.0 [95% CI, -16.9 to -7.9] points; P < .001; PP population: -13.2 [95% CI, -16.0 to -10.5] points; P < .001). Decreases in tinnitus loudness level were greater than 6 dB sensation level (SL; >half as loud) at week 6 for the bisensory treatment group, with little effect for the auditory-only treatment control group at week 6 of phase 1 (ITT population: -5.8 [95% CI, -9.5 to -2.2] dB; P = .08; PP population: -7.2 [95% CI, -11.4 to -3.1] dB; P = .03), and up to 11 dB SL at week 12 of phase 2 (ITT population: -10.9 [95% CI, -15.2 to -6.5] dB; P = .001; PP population: -14.1 [95% CI, -18.4 to -9.8] dB; P < .001). Decreased tinnitus loudness level and TFI scores extended into the washout phase, indicating a prolonged treatment effect. Conclusions and Relevance: This trial found that precisely timed bisensory treatment using stimuli and timing developed in a validated animal model was effective for adults with somatic tinnitus. Prolonged reduction in tinnitus symptoms can result from using an extended treatment duration. Trial Registration: ClinicalTrials.gov Identifier: NCT03621735.

Paragangliomas of the head and neck: a contemporary review.

Head and neck paragangliomas (HNPGLs) are slow-growing, vascular, typically benign tumors whose growth may induce significant lower cranial nerve deficits. While most tumors arise sporadically, a significant portion is associated with defined genetic syndromes. While surgical resection has historically been the gold standard, management strategies have evolved with acknowledgement of high surgical morbidity, slow tumor growth rates, and technological advances. Conservative management approaches via observation and newer radiation therapy techniques have become more common. This review seeks to provide an update on contemporary management strategies for HNPGLs and future directions.

Targeted molecular characterization of external auditory canal squamous cell carcinomas.

HYPOTHESIS: Squamous cell carcinomas (SCC) of the external auditory canal (EAC) may harbor unique genomic alterations that may explain aggressive behavior and differentiate these tumors from cutaneous SCCs of other subsites. BACKGROUND: EAC SCCs arise in a non-ultraviolet-exposed region of the head and neck, are often locally aggressive and may metastasize to lymph nodes or distant sites. The genomic alterations underlying cutaneous SCC of other sites are well-documented; however, mutational profiles of EAC SCC are less well characterized and may contribute to the unique anatomic site, high rates of recurrence and tumor spread. We performed targeted sequencing of a cohort of primary EAC SCCs to identify recurring and potentially targetable genomic alterations. METHODS: Genomic DNA was extracted from formalin-fixed paraffin-embedded specimens of 7 EAC SCCs and subjected to targeted DNA sequencing using a 227-gene panel. Somatic alterations and gene copy number alterations were annotated using our validated, in-house bioinformatics pipelines. RESULTS: In our EAC SCCs, we found recurrent alterations in TP53 and genes of receptor tyrosine kinase (eg, EGFR, FGFR) and PI3K pathways (eg, PIK3CA), similar to cutaneous SCCs of other head and neck sites. We also observed a high frequency of telomerase reverse transcriptase amplification and DNA methyltransferase 1 alterations, both of which are rarely observed in cutaneous SCCs of other sites. CONCLUSION: These data represent the first step toward precise molecular characterization of EAC SCCs that may lead to an enhanced understanding of tumor biology and modernized precision medicine approaches for unique tumors.Level of Evidence: NA.

Re-evaluating the prevalence and factors characteristic of catecholamine secreting head and neck paragangliomas.

INTRODUCTION: We sought to characterize the prevalence and factors characteristic of head and neck paragangliomas (HNPGLs) that secrete catecholamines to inform best practices for diagnosis and management. METHODS: This was a retrospective cohort study from 2000 to 2020 at a single-institution tertiary centre. One-hundred fifty-two patients (182 tumours) with HNPGLs with at least one measurement of urine or plasma catecholamines and/or catecholamine metabolite levels prior to treatment were included. We differentiated and characterized those patients with increased level(s) of any nature and those with 'clinically significant' versus 'clinically insignificant' catecholamine production. RESULTS: Thirty-one (20.4%) patients had increased catecholamine and/or catecholamine metabolite levels. In most patients, these levels were ≤5-fold above the upper limit of the reference range. Four of these 31 patients with increased levels were ultimately found to have an additional catecholamine secreting mediastinal paraganglioma or pheochromocytoma. Fourteen of 31 patients with HNPGL were deemed clinically significant secretors of catecholamines based on hyper-adrenergic symptoms and/or profound levels of normetanephrines. This cohort was enriched for patients with paragangliomas of the carotid body or cervical sympathetic chain and those with SDHB genetic mutations. Ultimately, the prevalence of clinically significant catecholamine secreting Hangs was determined to be 9.2% and 7.7% based on a per-patient and per-tumour basis, respectively. CONCLUSIONS: The rate of catecholamine excess in the current cohort of patients with HNPGLs was higher than previously reported. Neuroendocrine tumours of any anatomic subsite may secrete catecholamines, although not all increased laboratory level(s) are indicative of clinically significant catecholamine secretion causing symptoms or warranting adrenergic blockade.

Posttraumatic Dizziness: Navigating the Maze Towards Accurate Vestibular Diagnosis and Treatment.

OBJECTIVE: Highlight the importance of establishing a differential diagnosis to identify and treat multiple origins of dizziness in a patient following traumatic brain injury (TBI). PATIENT: 73-year-old man with TBI and temporal bone fracture developed posttraumatic bilateral multiple canal benign paroxysmal positional vertigo (BPPV). INTERVENTION: Multi-disciplinary diagnostic evaluation and vestibular rehabilitation (VR) treatment focused on canalith repositioning maneuvers (CRMs) and central adaptation. MAIN OUTCOME MEASURES: Diagnostic imaging, audiometric testing, clinical evaluation including video recordings of patterns of nystagmus, Dizziness Handicap Inventory (DHI). RESULTS: Systematic clinical examination identified multiple semicircular canal BPPV in addition to a suspected underlying unilateral hypofunction. Treatment focused on the appropriate CRMs and adaptation exercises. DHI scores improved significantly and patient returned to work and recreational activities. CONCLUSION: This Clinical Capsule Report highlights the importance of a comprehensive clinical evaluation of the TBI patient with dizziness when making an accurate diagnosis and treatment plan. Due to the complexity of differentiating between multiple canal BPPV in addition to other central and vestibular disorders, it is imperative for the clinician to have a clear understanding of nystagmus patterns for multicanal BPPV as well as other vestibular pathology.

Tinnitus and auditory cortex; Using adapted functional near-infrared-spectroscopy to expand brain imaging in humans.

OBJECTIVES: Phantom sound perception (tinnitus) may arise from altered brain activity within auditory cortex. Auditory cortex neurons in tinnitus animal models show increased spontaneous firing rates. This may be a core characteristic of tinnitus. Functional near-infrared spectroscopy (fNIRS) has shown similar findings in human auditory cortex. Current fNIRS approaches with cap recordings are limited to ∼3 cm depth of signal penetration due to the skull thickness. To address this limitation, we present an innovative fNIRS approach via probes adapted to the external auditory canal. The adapted probes were placed deeper and closer to temporal lobe of the brain to bypass confining skull bone and improve neural recordings. METHODS: Twenty adults with tinnitus and 20 nontinnitus controls listened to periods of silence and broadband noise (BBN) during standard cap and adapted ear canal fNIRS neuroimaging. The evaluators were not blinded, but the protocol and postprocessing for the two groups were identical. RESULTS: Standard fNIRS measurements in participants with tinnitus revealed increased auditory cortex activity during silence that was suppressed during auditory stimulation with BBN. Conversely, controls displayed increased activation with noise but not during silence. Importantly, adapted ear canal fNIRs probes showed similar hemodynamic responses seen with cap probes in both tinnitus and controls. CONCLUSIONS: In this proof of concept study, we have successfully fabricated, adapted, and utilized a novel fNIRS technology that replicates established findings from traditional cap fNIRS probes. This exciting new innovation, validated by replicating previous and current cap findings in auditory cortex, may have applications to future studies to investigate brain changes not only in tinnitus but in other pathologic states that may involve the temporal lobe and surrounding brain regions. LEVEL OF EVIDENCE: NA.

Tinnitus and auditory cortex: using adapted functional near-infrared spectroscopy to measure resting-state functional connectivity.

OBJECTIVE: Tinnitus, phantom sound perception, arises from aberrant brain activity within auditory cortex. In tinnitus animal models, auditory cortex neurons show increased spontaneous firing and neural synchrony. In humans, similar hyperactivation in auditory cortex has been displayed with functional near-infrared spectroscopy (fNIRS). Resting-state functional connectivity (RSFC) or increased connectivity between brain regions has also been shown in tinnitus using fNIRS. However, current fNIRS technology utilizes infrared (IR)-sources and IR-detectors placed on the scalp that restricts (~3 cm depth IR penetration) signal capture to outer cerebral cortex due to skin and skull bone. To overcome this limitation, in this proof of concept study, we adapted fNIRS probes to fit in the external auditory canal (EAC) to physically place IR-probes deeper within the skull thereby extracting neural signals from deeper auditory cortex. METHODS: Twenty adults with tinnitus and 20 nontinnitus controls listened to periods of silence and broadband noise before and after 5 min of silence to calculate RSFC. Concurrent scalp probes over auditory cortex and an adapted probe placed in the right EAC were utilized. RESULTS: For standard probes, left and right auditory cortex in tinnitus showed increased RSFC to each other and to other nonauditory cortices. Interestingly, adapted fNIRS probes showed trends toward increased RSFC. CONCLUSION: While many areas for the adapted probes did not reach significance, these data using a highly innovative and newly created probe adapting fNIRS technology to the EAC substantiates our previously published data in human tinnitus and concurrently validates this technology as a useful and expanded brain imaging modality.

Clinical Practice Guideline: Ménière's Disease.

OBJECTIVE: Ménière's disease (MD) is a clinical condition defined by spontaneous vertigo attacks (each lasting 20 minutes to 12 hours) with documented low- to midfrequency sensorineural hearing loss in the affected ear before, during, or after one of the episodes of vertigo. It also presents with fluctuating aural symptoms (hearing loss, tinnitus, or ear fullness) in the affected ear. The underlying etiology of MD is not completely clear, yet it has been associated with inner ear fluid (endolymph) volume increases, culminating in episodic ear symptoms (vertigo, fluctuating hearing loss, tinnitus, and aural fullness). Physical examination findings are often unremarkable, and audiometric testing may or may not show low- to midfrequency sensorineural hearing loss. Conventional imaging, if performed, is also typically normal. The goals of MD treatment are to prevent or reduce vertigo severity and frequency; relieve or prevent hearing loss, tinnitus, and aural fullness; and improve quality of life. Treatment approaches to MD are many and typically include modifications of lifestyle factors (eg, diet) and medical, surgical, or a combination of therapies. PURPOSE: The primary purpose of this clinical practice guideline is to improve the quality of the diagnostic workup and treatment outcomes of MD. To achieve this purpose, the goals of this guideline are to use the best available published scientific and/or clinical evidence to enhance diagnostic accuracy and appropriate therapeutic interventions (medical and surgical) while reducing unindicated diagnostic testing and/or imaging.

Plain Language Summary: Ménière's Disease.

This plain language summary explains Ménière's (pronounced men-yerz) disease (MD) to patients. The summary applies to patients aged 18 years and older with a suspected diagnosis of definite or probable MD. It is based on the 2020 "Clinical Practice Guideline: Ménière's Disease." This guideline uses published research to best advise health care providers and patients on the history and physical examination of patients with MD and how to diagnose and treat them. The guideline includes recommendations that are explained in this summary. Recommendations may not apply to every patient but can be used to facilitate shared decision making between patients and their health care providers.

Clinical Practice Guideline: Ménière's Disease Executive Summary.

OBJECTIVE: Ménière's disease (MD) is a clinical condition defined by spontaneous vertigo attacks (each lasting 20 minutes to 12 hours) with documented low- to midfrequency sensorineural hearing loss in the affected ear before, during, or after one of the episodes of vertigo. It also presents with fluctuating aural symptoms (hearing loss, tinnitus, or ear fullness) in the affected ear. The underlying etiology of MD is not completely clear, yet it has been associated with inner ear fluid volume increases, culminating in episodic ear symptoms (vertigo, fluctuating hearing loss, tinnitus, and aural fullness). Physical examination findings are often unremarkable, and audiometric testing may or may not show low- to midfrequency sensorineural hearing loss. Imaging, if performed, is also typically normal. The goals of MD treatment are to prevent or reduce vertigo severity and frequency; relieve or prevent hearing loss, tinnitus, and aural fullness; and improve quality of life. Treatment approaches to MD are many, and approaches typically include modifications of lifestyle factors (eg, diet) and medical, surgical, or a combination of therapies. PURPOSE: The primary purpose of this clinical practice guideline is to improve the quality of the diagnostic workup and treatment outcomes of MD. To achieve this purpose, the goals of this guideline are to use the best available published scientific and/or clinical evidence to enhance diagnostic accuracy and appropriate therapeutic interventions (medical and surgical) while reducing unindicated diagnostic testing and/or imaging.

A Family With a Carotid Body Paraganglioma and Thyroid Neoplasias With a New SDHAF2 Germline Variant.

At least 30% of all pheochromocytomas (PCCs)/paragangliomas (PGLs) arise in patients with a germline predisposition syndrome. Variants in succinate dehydrogenase subunits A, B, C, and D (SDHA, SDHB, SDHC, and SDHD) are the most common pathogenic germline alterations. Few pathogenic variants have been reported in succinate dehydrogenase assembly factor 2 (SDHAF2). Here, we describe a 30-year-old female patient who presented with a left-sided neck mass, which was later characterized as a carotid body PGL. Genetic testing revealed a likely pathogenic SDHAF2 variant (c.347G>A;p.W116X). Two sisters carried the same pathologic variant, and screening protocols were recommended. Whole-body MRI revealed thyroid nodules; this testing was followed by fine-needle aspiration, which confirmed papillary thyroid carcinoma in one sister and a follicular adenoma in the other. The two sisters then underwent hemithyroidectomy and total thyroidectomy, respectively. Because evidence for pathogenic variants in SDHAF2 causing predisposition to PCC/PGL is limited, we discuss the challenges in mutational variant interpretation and decision making regarding screening for associated tumors.

Institutional Experience of Treatment and Outcomes for Cutaneous Periauricular Squamous Cell Carcinoma.

OBJECTIVES: To report our institutional experience, management, and outcomes of cutaneous periauricular squamous cell carcinoma (SCC). STUDY DESIGN: Retrospective chart review. SETTING: Tertiary academic center. SUBJECTS: Patients undergoing treatment of cutaneous periauricular SCC from 2000 to 2016. RESULTS: A total of 112 patients had a median follow-up of 24.5 months, a mean ± SD age of 75.7 ± 10.6 years, and a strong male predominance (93.8%). Site distribution shows 87 (77.7%) auricular, 26 (23.2%) preauricular, and 10 (8.8%) postauricular lesions. Of auricular lesions, tumors involved the tragus (n = 3, 3.4%), helix/antihelix (n = 47, 54.0%), conchal bowl (n = 31, 35.6%), external auditory canal (n = 18, 16.1%), and lobule (n = 3, 3.4%). Most patients presented at stage I (52.7%) versus stages II (28.6%), III (6.3%), and IV (12.5%). Patients were largely treated surgically with primary tumor resection ranging from wide local excision to lateral temporal bone resection (± parotidectomy and neck dissection), with 17.0% and 5.4% receiving adjuvant radiation and chemoradiation, respectively. Metastatic spread was seen to the parotid (25.9%) and neck (26.8%), with most common cervical spread to level II. Overall survival, disease-specific survival, and disease-free survival at 3 years were 62%, 89%, and 56%, respectively. Nodal disease was associated with worse disease-specific survival (P < .001) and disease-free survival (P = .042). Pre- and postauricular sites were associated with worse overall survival (P = .007) relative to auricular sites. CONCLUSION: Among cutaneous SCC, periauricular subsites pose treatment challenges related to surrounding anatomy and represent a unique tumor population. The reported propensity toward recurrence and patterns of metastasis may better guide treatment of aggressive tumors to include regional nodal dissection.

Evaluating Cholinergic Receptor Expression in Guinea Pig Primary Auditory and Rostral Belt Cortices After Noise Damage Using [3H]Scopolamine and [18F]Flubatine Autoradiography.

Noise-induced hearing loss leads to anatomic and physiologic changes in primary auditory cortex (A1) and the adjacent dorsal rostral belt (RB). Since acetylcholine is known to modulate plasticity in other cortical areas, changes in A1 and RB following noise damage may be due to changes in cholinergic receptor expression. We used [3H]scopolamine and [18F]flubatine binding to measure muscarinic acetylcholine receptor (mAChR) and nicotinic acetylcholine receptor (nAChR) expression, respectively, in guinea pig A1 and RB 3 weeks following unilateral, left ear noise exposure, and a temporary threshold shift in hearing. [3H]Scopolamine binding decreased in right A1 and RB (contralateral to noise) compared to sham controls across all cortical layers. [18F]Flubatine binding showed a nonsignificant upward trend in right A1 following noise but only significantly increased in right RB and 2 layers of left RB (ipsilateral to noise). This selective response may ultimately influence cortical plasticity and function. The mechanism(s) by which cholinergic receptors are altered following noise exposure remain unknown. However, these data demonstrate noise exposure may differentially influence mAChRs that typically populate interneurons in A1 and RB more than nAChRs that are traditionally located on thalamocortical projections and provide motivation for cholinergic imaging in clinical patient populations of temporary or permanent hearing loss.

Tinnitus Management in Lateral Skull Base Lesions.

Tinnitus, the phantom perception of sound in the absence of a physical sound source, is a complex problem with multiple etiologies. While most commonly presenting in a subjective fashion caused by measurable hearing loss, other etiologies including lateral skull base tumors that encroach on middle and inner ear structures can lead to phantom sound perception as well. In addition to discussing the basic background of tinnitus, here we also review current theories of etiology that include central auditory and nonauditory neural mechanisms and potential treatments that range from sound therapy to medications to cognitive and behavioral therapies and cranial nerve and brain stimulation. One main purpose of this article is to relate tinnitus causes to skull base tumors, surgical removal, and resultant sequelae, including damage to cranial nerves resulting in audiovestibular dysfunction. We also discuss the utility of microvascular decompression for both tumor and nontumor-associated tinnitus and the current literature regarding hearing preservation rates and tinnitus perception, where documented, with the three common treatment modalities employed for most lateral skull base tumors that includes watchful waiting with serial imaging, stereotactic radiosurgery and primary surgical resection using hearing preservation and hearing ablative approaches. The management of skull base tumors is a complex process that depending upon the approach and sequelae, may lead to manageable or worsening phantom sound perception that must be considered when discussing the multiple treatment options with patients.

Outcomes of unilateral idiopathic sudden sensorineural hearing loss: Two decades of experience.

OBJECTIVES: (a) Determine the demographic and medical risk factors for patients who presented with unilateral idiopathic sudden sensorineural hearing loss (ISSNHL); (b) identify treatments that patients underwent; (c) evaluate the adequacy of follow-up and compliance with long-term hearing rehabilitation. METHODS: Retrospective review of patients who presented with unilateral ISSNHL between January 1998 and December 2017 at a tertiary care academic medical center. RESULTS: Two hundred-four patients met inclusion criteria. Of these, 129 (63.2%) did not undergo treatment at an outside hospital prior to our evaluation. In this subgroup, the average pretreatment pure tone average (PTA) was 61.9 ± 2.5 dB (dB). The most common treatment was oral steroids and was recommended in 76 patients (59.9%). Patients also underwent intratympanic (IT) steroid injections (7.2%) or oral steroids followed by salvage IT injections (19.4%). Mean follow-up duration was 17.9 (±29.2) months, and posttreatment PTA (45.6 ± 2.6 dB) was significantly better than baseline (P < .001). In this cohort, hearing amplification was infrequently recommended. Less than 20% of patients reported active hearing amplification use at their most recent visit. At follow-up, 90 patients (69.8%) reported subjective improvement in hearing after treatment. Only 55 patients (42.6%) showed improvement in PTA compared to their pretreatment audiograms. CONCLUSION: Many patients with ISSNHL experienced audiometric improvement after treatments, but most had persistent hearing loss. The duration of follow-up was short. Most patients did not use long-term hearing amplification. Future studies are needed to identify factors that contribute to reduced follow-up and low compliance with hearing amplification use in ISSNHL. LEVEL OF EVIDENCE: 2c.

Auditory-somatosensory bimodal stimulation desynchronizes brain circuitry to reduce tinnitus in guinea pigs and humans.

The dorsal cochlear nucleus is the first site of multisensory convergence in mammalian auditory pathways. Principal output neurons, the fusiform cells, integrate auditory nerve inputs from the cochlea with somatosensory inputs from the head and neck. In previous work, we developed a guinea pig model of tinnitus induced by noise exposure and showed that the fusiform cells in these animals exhibited increased spontaneous activity and cross-unit synchrony, which are physiological correlates of tinnitus. We delivered repeated bimodal auditory-somatosensory stimulation to the dorsal cochlear nucleus of guinea pigs with tinnitus, choosing a stimulus interval known to induce long-term depression (LTD). Twenty minutes per day of LTD-inducing bimodal (but not unimodal) stimulation reduced physiological and behavioral evidence of tinnitus in the guinea pigs after 25 days. Next, we applied the same bimodal treatment to 20 human subjects with tinnitus using a double-blinded, sham-controlled, crossover study. Twenty-eight days of LTD-inducing bimodal stimulation reduced tinnitus loudness and intrusiveness. Unimodal auditory stimulation did not deliver either benefit. Bimodal auditory-somatosensory stimulation that induces LTD in the dorsal cochlear nucleus may hold promise for suppressing chronic tinnitus, which reduces quality of life for millions of tinnitus sufferers worldwide.

Immediate and Long-term Hearing Outcomes With the Middle Cranial Fossa Approach for Vestibular Schwannoma Resection.

OBJECTIVE: To analyze the immediate postoperative and long-term hearing outcome data in patients who have undergone hearing preservation attempts with the middle cranial fossa (MCF) approach for the resection of sporadic vestibular schwannoma. STUDY DESIGN: Retrospective review of a surgical patient cohort. SETTING: Tertiary academic referral center. PATIENTS: Adult patients with unilateral sporadic vestibular schwannoma. INTERVENTION: Surgical treatment with a MCF approach. MAIN OUTCOME MEASURE: Comparison of pre- and postoperative audiometric data in accordance with the 1995 and 2012 American Academy of Otolaryngology/Head and Neck Surgery guidelines on reporting hearing outcomes and with a word recognition score only scale. Long-term hearing outcome data were analyzed in the following postoperative groups: 3 to 5, 6 to 8, 9 to 11, and 12+ years after surgery. RESULTS: From 1999 to 2016, 174 patients underwent the MCF approach and 155 of them met inclusion criteria for analysis of hearing outcome data. Class A or B hearing was preserved in 70% of the entire cohort after recovery. Seventy-one patients with measurable hearing met criteria for long-term data analysis. The rate of American Academy of Otolaryngology/Head and Neck Surgery class A or B hearing preservation was 82% at 3 to 5 years and declined thereafter. The rate of word recognition score class I or II hearing preservation was 98% at 3 to 5 years and declined less rapidly thereafter. Patients with preoperative Class A hearing had significantly higher rates of successful hearing preservation at all postoperative intervals. CONCLUSION: Delayed hearing loss occurs in a progressively increasing fashion but speech understanding remains durable for a majority of patients whose hearing is initially preserved with the MCF approach.

Human central auditory plasticity: A review of functional near-infrared spectroscopy (fNIRS) to measure cochlear implant performance and tinnitus perception.

OBJECTIVE: Functional near-infrared spectroscopy (fNIRS) is an emerging noninvasive technology used to study cerebral cortex activity. Being virtually silent and compatible with cochlear implants has helped establish fNIRS as an important tool when investigating auditory cortex as well as cortices involved with hearing and language processing in adults and during child development. With respect to this review article, more recently, fNIRS has also been used to investigate central auditory plasticity following hearing loss and tinnitus or phantom sound perception. METHODS: Here, we review the currently available literature reporting the use of fNIRS in human studies with cochlear implants and tinnitus to measure human central auditory cortical circuits. We also provide the reader with detailed reviews of the technology and traditional recording paradigms/methods used in these auditory-based studies. RESULTS: The purpose of this review article is to summarize theoretical advancements in our understanding of the neurocognitive mechanisms underlying auditory processes and their plasticity through fNIRS research of human auditory performance with cochlear implantation and plasticity that may contribute to the central percepts of tinnitus. CONCLUSION: fNIRS is an emerging noninvasive brain imaging technology that has wide reaching application that can be applied to human studies involving cochlear implants and tinnitus. LEVEL OF EVIDENCE: N/A.