Minimum intraoperative testing battery for cochlear implantation: the international practice trend.

PURPOSE: In cochlear implantation (CI) surgery, there are a wide variety of intraoperative tests available. However, no clear guide exists on which tests must be performed as the minimum intraoperative testing battery. Toward this end, we studied the usage patterns, recommendations, and attitudes of practitioners toward intraoperative testing. METHODS: This study is a multicentric international survey of tertiary referral CI centers. A survey was developed and administered to a group of CI practitioners (n = 34) including otologists, audiologists and biomedical engineers. Thirty six participants were invited to participate in this study based on a their scientific outputs to the literature on the intraoperative testing in CI field and based on their high load of CI surgeries. Thirty four, from 15 countries have accepted the invitation to participate. The participants were asked to indicate the usage trends, perceived value, influence on decision making and duration of each intraoperative test. They were also asked to indicate which tests they believe should be included in a minimum test battery for routine cases. RESULTS: Thirty-two (94%) experts provided responses. The most frequently recommended tests for a minimum battery were facial nerve monitoring, electrode impedance measurements, and measurements of electrically evoked compound action potentials (ECAPs). The perceived value and influence on surgical decision-making also varied, with high-resolution CT being rated the highest on both measures. CONCLUSION: Facial nerve monitoring, electrode impedance measurements, and ECAP measurements are currently the core tests of the intraoperative test battery for CI surgery.

International Consensus Statements on Intraoperative Testing for Cochlear Implantation Surgery.

OBJECTIVES: A wide variety of intraoperative tests are available in cochlear implantation. However, no consensus exists on which tests constitute the minimum necessary battery. We assembled an international panel of clinical experts to develop, refine, and vote upon a set of core consensus statements. DESIGN: A literature review was used to identify intraoperative tests currently used in the field and draft a set of provisional statements. For statement evaluation and refinement, we used a modified Delphi consensus panel structure. Multiple interactive rounds of voting, evaluation, and feedback were conducted to achieve convergence. RESULTS: Twenty-nine provisional statements were included in the original draft. In the first voting round, consensus was reached on 15 statements. Of the 14 statements that did not reach consensus, 12 were revised based on feedback provided by the expert practitioners, and 2 were eliminated. In the second voting round, 10 of the 12 revised statements reached a consensus. The two statements which did not achieve consensus were further revised and subjected to a third voting round. However, both statements failed to achieve consensus in the third round. In addition, during the final revision, one more statement was decided to be deleted due to overlap with another modified statement. CONCLUSIONS: A final core set of 24 consensus statements was generated, covering wide areas of intraoperative testing during CI surgery. These statements may provide utility as evidence-based guidelines to improve quality and achieve uniformity of surgical practice.

Povidone-Iodine Fails to Eradicate Chronic Suppurative Otitis Media and Demonstrates Ototoxic Risk in Mice.

HYPOTHESIS: Commercially available povidone-iodine solution can eliminate biofilms and persister cells rapidly in in vivo achievable concentrations without inducing ototoxicity. BACKGROUND: Chronic suppurative otitis media (CSOM) is a substantial global problem. Current treatment options often induce a temporary remission without leading to a permanent cessation of symptoms secondary to the treatments' inability to eliminate persister cells. Povidone-iodine has been shown to be able to clear biofilm and planktonic cells in in vitro assays, but there are reports of ototoxic effects limiting its clinical utility. METHODS: Bacterial and biofilm growth with quantification by spectrophotomer, murine auditory brainstem response (ABR), and distortion product otoacoustic emissions, immunohistochemistry, in vivo povidone-iodine treatment of murine CSOM, persister cell assay. RESULTS: Commercially available 10% povidone-iodine solution is able to completely eradicate multiple clinical strains of Pseudomonas aeruginosa and Staphylococcus aureus in vitro with 10 minutes of exposure. Mice that have received a transtympanic injection of 1% povidone-iodine solution did not have significantly different auditory brainstem response or distortion product otoacoustic emission results compared with the control. Mice that received a povidone-iodine scrub or 10% povidone-iodine solution had significantly worsened hearing (25- and 13-dB increase in threshold, respectively; p < 0.05). In vivo CSOM infection recurred in all mice after the completion of treatment with 10% povidone-iodine solution, and there was no improvement in the bacterial load after treatment, indicating in vivo failure of therapy. CONCLUSION: Povidone-iodine solution is effective at eliminating biofilm and persister cells in vitro at in vivo achievable concentrations but fails in vivo most likely because of kinetics of distribution in vivo. Even if drug distribution could be improved, the therapeutic window is likely to be too small given that the diluted solution does not have ototoxic potential, whereas while the scrub variant, which contains detergents, and the undiluted solution are ototoxic after a single treatment.

A scoping review of global aminoglycoside antibiotic overuse: A potential opportunity for primary ototoxicity prevention.

BACKGROUND: Aminoglycosides are widely used, broad-spectrum antibiotics with significant potential for ototoxicity. Global efforts to prevent ototoxicity must account for aminoglycoside overuse and non-prescription use. OBJECTIVES: The goals of this study were to a) estimate the prevalence of aminoglycoside overuse by synthesizing evidence on self-medication, over the counter (OTC) availability, and household antibiotic storage for later use, and to report the specific aminoglycosides used and the predictors of overuse, and b) leverage this information to comment on potential risk of ototoxicity. METHODS: Two systematic search strings were conducted to extract peer-reviewed articles published from 2005 to 2020. The first focused on overuse of aminoglycoside antibiotics. The second focused on potentially ototoxic effects of aminoglycosides related to drug overuse. RESULTS: A total of 26 articles were included (first search string: n = 21; second search string: n = 5). The prevalence of aminoglycoside self-medication was high and household storage and OTC availability of aminoglycosides was common. Gentamicin was the most commonly overused aminoglycoside. No studies provided information on antibiotic dosing or resultant toxicities, including ototoxicity. CONCLUSIONS: The limited available evidence indicates that antibiotic overuse (self-medication, home storage, and non-prescription availability) is relatively common, especially in low resource settings, and that aminoglycoside antibiotics comprise a variable, but concerning, proportion of non-prescribed antibiotics. Additional evidence is needed to evaluate the relationship between these dispensing patterns and ototoxicity.

Perceptions of Sound Quality and Enjoyment After Cochlear Implantation.

OBJECTIVES: To characterize the quality and enjoyment of sound by cochlear implant (CI) recipients and identify predictors of these outcomes after cochlear implantation. STUDY DESIGN: Cross-sectional study. SETTING: A tertiary care hospital. METHODS: Surveys based on the Hearing Implant Sound Quality Index were sent to all patients who received a CI at a tertiary care hospital from 2000 to 2019. Survey questions prompted CI recipients to characterize enjoyment and quality of voices, music, and various sounds. RESULTS: Of the 339 surveys, 60 (17.7%) were returned with complete data. CI recipients had a mean ± SD age of 62.5 ± 17.4 years with a mean 8.0 ± 6.1 years since CI surgery. Older current age and age at implantation significantly predicted lower current sound quality (P < .05) and sound enjoyment (P < .05), as well as worsening of sound quality (P < .05) and sound enjoyment (P < .05) over time. Greater length of implantation was associated with higher reported quality and enjoyment (r = 0.4, P < .001; r = 0.4, P < .05), as well as improvement of sound quality (r = 0.3, P < .05) but not sound enjoyment over time. CONCLUSION: Recipients who had CIs for a longer period had improved quality of sound perception, suggesting a degree of adaptation. However, CI recipients with implantation at an older age reported poorer sound quality and enjoyment as well as worsening sound quality and enjoyment over time, indicating that age-related changes influence outcomes of cochlear implantation.

Preoperative Criteria Predict Operative Time Variability Within Tympanoplasty Procedures.

OBJECTIVE: To identify preoperative patient and surgical parameters that predict operative time variability within tympanoplasty current procedural terminology (CPT) codes. STUDY DESIGN: Retrospective. SETTING: Tertiary referral center. PATIENTS: One hundred twenty eight patients who underwent tympanoplasty (CPT code 69631) or tympanoplasty with ossicular chain reconstruction (69633) by a single surgeon over 3 years. INTERVENTIONS: Procedures were preoperatively assigned a complexity modifier: Level 1 (small or posterior perforation able to be repaired via transcanal approach), Level 2 (large perforation or other factor requiring postauricular approach), or Level 3 (cholesteatoma or severe infection). MAIN OUTCOME MEASURES: Total in-room time (nonoperative time plus actual operative time). RESULTS: Consideration of preoperative parameters including surgical complexity, surgical facility, use of facial nerve monitoring, laser usage, resident involvement, revision surgery, and underlying patient characteristics (American Society of Anesthesiologists [ASA] score, body mass index [BMI]) accounted for up to 69% of surgical time variance. Across both CPT codes, surgical complexity levels accurately stratified operative times (p < 0.05). Total time was longer (by 30.0 min for 69631, 55.4 min for 69633) in Level 3 procedures compared with Level 2, while Level 1 cases were shorter (27.6, 33.9 min). Resident involvement added 25 and 32 minutes to total time (p < 0.02). Nonoperative preparation times were longer (22.1, 15.4 min) in the main hospital compared with ambulatory surgical center (p < 0.001). CONCLUSIONS: There is significant surgical time variability within tympanoplasty CPT codes, which can be accurately predicted by the preoperative assignment of complexity level modifiers and consideration of patient and surgical factors. Application of complexity modifiers can enable more efficient surgical scheduling.

Tensor Veli Palatinopexy as a Novel Treatment for Eustachian Tube Dysfunction: A Cadaveric Feasibility Study.

OBJECTIVE: To demonstrate the feasibility of a novel procedure whereby a suture is placed transorally in the tensor veli palatini muscle to tighten it, thereby dilating the cartilaginous portion of the eustachian tube (ET). STUDY DESIGN: The study design was a prospective cadaveric experiment to examine the feasibility of a novel treatment for ET dysfunction. SETTING: Academic medical center in a research-oriented operating room with intraoperative computed tomography (CT) capabilities. METHODS: Seven fresh-frozen cadaver heads were obtained, each of which was thawed for 36 hours prior to use. The preprocedural volumes of the cartilaginous ET were measured by filling the ET with an iodine-containing radiocontrast agent via the nasopharynx and then obtaining CT images. Submucosal flaps in the soft palate were raised, and sutures were placed in the tensor veli palatini bilaterally to increase tension. After completion of the procedure, contrast placement and CT imaging were repeated. Three-dimensional models of the ETs were created, and the volumes were measured and compared. RESULTS: Of the 14 ETs evaluated, 13 showed an increase in postprocedure volume. On average, postprocedure volumes showed a 57% increase from preprocedure volumes (mean relative change, 57.1%; P = .013). CONCLUSION: Placement of a tension-holding suture in the tensor veli palatini muscle can reliably dilate the cartilaginous portion of the ET. Such a procedure may be useful in the treatment of ET dysfunction.

Outcomes of a novel alloplastic technique for external auditory canal repair in tympanomastoidectomy.

OBJECTIVE: To analyze surgical outcomes of a novel alloplastic reconstruction technique for partial external auditory canal (EAC) defects in tympanomastoidectomy. METHODS: Retrospective study of 51 patients with cholesteatoma who underwent repair of partial EAC defects during tympanomastoidectomy at a tertiary referral center over 8 years. Nineteen patients were treated with a novel alloplastic graft technique using hydroxyapatite cement and bone pâté for EAC repair. Thirty-two patients treated with traditional cartilage repair of the EAC served as a control group. The primary outcomes measured were postoperative cholesteatoma recurrence rates, infection rates, and mean air-bone gap (ABG). RESULTS: Twenty of the 51 cases (39.2%) were revision surgeries for cholesteatoma recidivism, with a greater proportion of revision surgeries in the alloplastic group (57.9% vs 28.1%, P = .04). There was no significant difference in postoperative cholesteatoma recurrence (P = 1.00) or infection rates (P = .64) between the two techniques, with the alloplastic group experiencing slightly lower rates of recurrence (36.8%) and infection (5.3%) than cartilage repair (37.5% recurrence, 12.5% infection). Mean postoperative ABGs were comparable between the alloplastic (21.5 dB) and cartilage group (26.0 dB, P = .10). CONCLUSIONS: Composite alloplastic and bone pâté reconstruction is an effective technique to repair partial EAC defects in tympanomastoidectomy, with comparable postoperative hearing outcomes and no increased risk of cholesteatoma recurrence or infection compared to traditional cartilage repair. Recidivism rates were relatively high in both groups, likely due to the high rate of revision surgeries and aggressive nature of cholesteatoma within the cohort. LEVEL OF EVIDENCE: Level 3B.

Expanding Access: Cost-effectiveness of Cochlear Implantation and Deaf Education in Asia.

OBJECTIVE: To determine the cost-effectiveness of cochlear implantation (CI) with mainstream education and deaf education with sign language for treatment of children with profound sensorineural hearing loss in low- and lower-middle income countries in Asia. STUDY DESIGN: Cost-effectiveness analysis. SETTING: Bangladesh, Cambodia, India, Indonesia, Nepal, Pakistan, Philippines, and Sri Lanka participated in the study. SUBJECTS AND METHODS: Costs were obtained from experts in each country with known costs and published data, with estimation when necessary. A disability-adjusted life-years model was applied with 3% discounting and 10-year length of analysis. A sensitivity analysis was performed to evaluate the effect of device cost, professional salaries, annual number of implants, and probability of device failure. Cost-effectiveness was determined with the World Health Organization standard of cost-effectiveness ratio per gross domestic product (CER/GDP) per capita <3. RESULTS: Deaf education was cost-effective in all countries except Nepal (CER/GDP, 3.59). CI was cost-effective in all countries except Nepal (CER/GDP, 6.38) and Pakistan (CER/GDP, 3.14)-the latter of which reached borderline cost-effectiveness in the sensitivity analysis (minimum, maximum: 2.94, 3.39). CONCLUSION: Deaf education and CI are largely cost-effective in participating Asian countries. Variation in CI maintenance and education-related costs may contribute to the range of cost-effectiveness ratios observed in this study.

Comparison of Transmastoid and Middle Fossa Approaches for Superior Canal Dehiscence Repair: A Multi-institutional Study.

OBJECTIVE: To compare outcomes for patients undergoing a transmastoid approach versus a middle fossa craniotomy approach with plugging and/or resurfacing for repair of superior semicircular canal dehiscence. Outcome measures include symptom resolution, hearing, operative time, hospital stay, complications, and revision rates. STUDY DESIGN: Multicenter retrospective comparative cohort study. SETTINGS: Three tertiary neurotology centers. SUBJECTS AND METHODS: All adult patients undergoing repair for superior canal dehiscence between 2006 and 2017 at 3 neurotology centers were included. Demographics and otologic history collected by chart review. Imaging, audiometric data, and vestibular evoked myogenic potential measurements were also collected for analysis. RESULTS: A total of 68 patients (74 ears) were included in the study. Twenty-one patients underwent middle fossa craniotomy repair (mean age, 47.9 years), and 47 underwent transmastoid repair (mean age, 48.0 years). There were no significant differences in age or sex distribution between the groups. The transmastoid group experienced a significantly shorter duration of hospitalization and lower recurrence rate as compared with the middle fossa craniotomy group (3.8% vs 33%). Both groups experienced improvement in noise-induced vertigo, autophony, pulsatile tinnitus, and nonspecific vertigo. There was no significant difference among symptom resolution between groups. Additionally, there was no significant difference in audiometric outcomes between the groups. CONCLUSION: Both the transmastoid approach and the middle fossa craniotomy approach for repair of superior canal dehiscence offer symptom resolution with minimal risk. The transmastoid approach was associated with shorter hospital stays and lower recurrence rate as compared with the middle fossa craniotomy approach.

Otolaryngology and the Global Burden of Disease.

The Global Burden of Disease (GBD) project provides longitudinal analysis of the global burden of otolaryngologic diseases by measuring the all-cause mortality, years of life lost, the years of life lived with disability, and disability-adjusted life years. Hearing loss burden is assessed overall and as sequelae of other diseases, such as otitis media or meningitis. Using these measures, we can appreciate the high prevalence and disability related to hearing loss globally. Other otolaryngologic diseases that contribute to the GBD include otitis media, cleft lip and palate, head and neck cancer, facial trauma, and oral disorders.

Otoacoustic Emissions in Rural Nicaragua: Cost Analysis and Implications for Newborn Hearing Screening.

Objective (1) Determine the incidence and risk factors for congenital hearing loss. (2) Perform cost analysis of screening programs. Study Design Proportionally distributed cross-sectional survey. Setting Jinotega, Nicaragua. Subjects and Methods Otoacoustic emissions (OAEs) were used to screen 640 infants <6 months of age from neonatal intensive care unit, institutional, and home birth settings. Data on 15 risk factors were analyzed. Cost of 4 implementation strategies was studied: universal screening, screening at the regional health center (RHC), targeted screening, and screening at the RHC plus targeted screening. Cost-effectiveness analysis over 10 years was based on disability-adjusted life year estimates, with the World Health Organization standard of cost-effectiveness ratio (CER) / gross domestic product (GDP) <3, with GDP set at $4884.15. Results Thirty-eight infants failed the initial OAE (5.94%). In terms of births, 325 (50.8%) were in the RHC, 69 (10.8%) in the neonatal intensive care unit, and 29 (4.5%) at home. Family history and birth defect were significant in univariate analysis; birth defect was significant in multivariate analysis. Cost-effectiveness analysis demonstrated that OAE screening is cost-effective without treatment (CER/GDP = 0.06-2.00) and with treatment (CER/GDP = 0.58-2.52). Conclusions Our rate of OAE failures was comparable to those of developed countries and lower than hearing loss rates noted among Nicaraguan schoolchildren, suggesting acquired or progressive etiology in the latter. Birth defects and familial hearing loss correlated with OAE failure. OAE screening of infants is feasible and cost-effective in rural Nicaragua, although highly influenced by estimated hearing loss severity in identified infants and the high travel costs incurred in a targeted screening strategy.

Nervus Intermedius Symptoms following Surgical or Radiation Therapy for Vestibular Schwannoma.

OBJECTIVES: This study compares the functional outcomes of nevus intermedius impairment following surgery, radiation, or observation for the treatment of vestibular schwannoma. STUDY DESIGN: Retrospective cohort study. SETTINGS: Tertiary care medical center. SUBJECTS AND METHODS: We retrospectively examined 141 charts of patients with a vestibular schwannoma seen in the Dartmouth-Hitchcock Acoustic Neuroma Clinic between 2012 and 2014. Seventy-one patients underwent intervention (including radiation) as their primary treatment, and 70 were treated with observation. As part of routine care, patients were interviewed at clinic visits and with a questionnaire assessing nervus intermedius impairment. RESULTS: At presentation, 25 patients (19%) reported nervus intermedius impairment. Most common disturbances were xerophthalmia (dry eyes, 13%) and dysgeusia (taste alteration, 7.6%). Postintervention, 35 patients (53%) had ≥1 symptoms of nervus intermedius dysfunction, which is increased in comparison with patients in the observation group (17 patients, 26.5%, P < .05). Twelve intervention patients had symptoms resolve postoperatively, making no long-term difference between the observation and intervention groups (P = .20). Motor function of the facial nerve postoperatively is correlated with nervus intermedius symptoms. Surgical approaches were compared with radiation therapy, and no significant difference in nervus intermedius outcomes was found. CONCLUSION: This study demonstrates the clinical importance of monitoring nervus intermedius symptoms, since a high percentage of all patients undergoing intervention will be symptomatic during management. Patients with motor dysfunction are at a higher risk of developing nervus intermedius sequelae and need close follow-up. Although impairment is common, many symptoms will improve over time with no long-term difference between intervention patients and those under observation.

Cost Effectiveness of Childhood Cochlear Implantation and Deaf Education in Nicaragua: A Disability Adjusted Life Year Model.

INTRODUCTION: Cochlear implantation (CI) is a common intervention for severe-to-profound hearing loss in high-income countries, but is not commonly available to children in low resource environments. Owing in part to the device costs, CI has been assumed to be less economical than deaf education for low resource countries. The purpose of this study is to compare the cost effectiveness of the two interventions for children with severe-to-profound sensorineural hearing loss (SNHL) in a model using disability adjusted life years (DALYs). METHODS: Cost estimates were derived from published data, expert opinion, and known costs of services in Nicaragua. Individual costs and lifetime DALY estimates with a 3% discounting rate were applied to both two interventions. Sensitivity analysis was implemented to evaluate the effect on the discounted cost of five key components: implant cost, audiology salary, speech therapy salary, number of children implanted per year, and device failure probability. RESULTS: The costs per DALY averted are $5,898 and $5,529 for CI and deaf education, respectively. Using standards set by the WHO, both interventions are cost effective. Sensitivity analysis shows that when all costs set to maximum estimates, CI is still cost effective. CONCLUSION: Using a conservative DALY analysis, both CI and deaf education are cost-effective treatment alternatives for severe-to-profound SNHL. CI intervention costs are not only influenced by the initial surgery and device costs but also by rehabilitation costs and the lifetime maintenance, device replacement, and battery costs. The major CI cost differences in this low resource setting were increased initial training and infrastructure costs, but lower medical personnel and surgery costs.

Posterior semicircular canal dehiscence: CT prevalence and clinical symptoms.

OBJECTIVE: To estimate the prevalence of and symptoms associated with posterior semicircular canal dehiscence (PSCD) compared to superior semicircular canal dehiscence (SSCD) and nondehiscent semicircular canals (NDSC). STUDY DESIGN: Retrospective review. SETTING: Academic tertiary referral center. PATIENTS: Review of 412 temporal bone CT scans and associated patient records, excluding patients with prior mastoid or skull base surgery. INTERVENTION(S): CT images (0.625 mm thick) were reviewed in the planes of the semicircular canals. Patient demographics and symptoms were tabulated and analyzed. MAIN OUTCOME MEASURE(S): Prevalence of PSCD and SSCD; degree of hearing loss; presence or absence of aural fullness, autophony, tinnitus, pulsatile tinnitus, disequilibrium, vertigo, and Tullio phenomenon. RESULTS: Review of the 412 CT scans revealed 5 cases of PSCD (1.2%) and 20 cases of SSCD (4.9%). All patients with PSCD were male, aged 16 to 73 years. One patient with PSCD reported tinnitus, autophony, disequilibrium, vertigo, and Tullio phenomenon; 2 patients reported only tinnitus and aural fullness, and 1 patient had no symptoms. PSCD was commonly associated with SSCD. There were no significant differences in symptoms between PSCD patients and the other groups. There were, however, statistically significant differences between SSCD patients and NDSC patients in the rates of autophony, tinnitus, and disequilibrium. CONCLUSION: The prevalence of PSCD in patients undergoing temporal bone CT scans is considerably less than SSCD (1.2% versus 4.9%), and the 2 conditions commonly coexist. Given the small numbers in our study, we were not able to demonstrate any distinguishable clinical features for the PSCD patients.

Clinical practice guideline: sudden hearing loss.

OBJECTIVE: Sudden hearing loss (SHL) is a frightening symptom that often prompts an urgent or emergent visit to a physician. This guideline provides evidence-based recommendations for the diagnosis, management, and follow-up of patients who present with SHL. The guideline primarily focuses on sudden sensorineural hearing loss (SSNHL) in adult patients (aged 18 and older). Prompt recognition and management of SSNHL may improve hearing recovery and patient quality of life (QOL). Sudden sensorineural hearing loss affects 5 to 20 per 100,000 population, with about 4000 new cases per year in the United States. This guideline is intended for all clinicians who diagnose or manage adult patients who present with SHL. PURPOSE: The purpose of this guideline is to provide clinicians with evidence-based recommendations in evaluating patients with SHL, with particular emphasis on managing SSNHL. The panel recognized that patients enter the health care system with SHL as a nonspecific, primary complaint. Therefore, the initial recommendations of the guideline deal with efficiently distinguishing SSNHL from other causes of SHL at the time of presentation. By focusing on opportunities for quality improvement, the guideline should improve diagnostic accuracy, facilitate prompt intervention, decrease variations in management, reduce unnecessary tests and imaging procedures, and improve hearing and rehabilitative outcomes for affected patients. RESULTS: The panel made strong recommendations that clinicians should (1) distinguish sensorineural hearing loss from conductive hearing loss in a patient presenting with SHL; (2) educate patients with idiopathic sudden sensorineural hearing loss (ISSNHL) about the natural history of the condition, the benefits and risks of medical interventions, and the limitations of existing evidence regarding efficacy; and (3) counsel patients with incomplete recovery of hearing about the possible benefits of amplification and hearing-assistive technology and other supportive measures. The panel made recommendations that clinicians should (1) assess patients with presumptive SSNHL for bilateral SHL, recurrent episodes of SHL, or focal neurologic findings; (2) diagnose presumptive ISSNHL if audiometry confirms a 30-dB hearing loss at 3 consecutive frequencies and an underlying condition cannot be identified by history and physical examination; (3) evaluate patients with ISSNHL for retrocochlear pathology by obtaining magnetic resonance imaging, auditory brainstem response, or audiometric follow-up; (4) offer intratympanic steroid perfusion when patients have incomplete recovery from ISSNHL after failure of initial management; and (5) obtain follow-up audiometric evaluation within 6 months of diagnosis for patients with ISSNHL. The panel offered as options that clinicians may offer (1) corticosteroids as initial therapy to patients with ISSNHL and (2) hyperbaric oxygen therapy within 3 months of diagnosis of ISSNHL. The panel made a recommendation against clinicians routinely prescribing antivirals, thrombolytics, vasodilators, vasoactive substances, or antioxidants to patients with ISSNHL. The panel made strong recommendations against clinicians (1) ordering computerized tomography of the head/brain in the initial evaluation of a patient with presumptive SSNHL and (2) obtaining routine laboratory tests in patients with ISSNHL.

Ganglioneuroma of the internal auditory canal presenting as a vestibular schwannoma.

In most series, 90% of cerebellopontine angle tumors are vestibular schwannomas. Meningiomas and epidermoid tumors follow with decreased frequency. Ganglioneuroma is a benign tumor usually found in the retroperitoneum and posterior mediastinum. We report a case of a 21-year-old man with gradual sensorineural hearing loss and a minimally enhancing lesion of the internal auditory canal, which was excised through a middle fossa approach and found histologically to be a ganglioneuroma. Like vestibular schwannomas, these lesions are benign in nature and may be managed in a similar fashion, although the possibility of malignant transformation may support surgical resection over conservative management or radiosurgery. Ganglioneuromas should be considered in patients with atypical radiographic findings for vestibular schwannomas.

Aminoglycoside ototoxicity in Nicaraguan children: patient risk factors and mitochondrial DNA results.

OBJECTIVE: Aminoglycoside ototoxicity remains a major problem in developing countries and accounts for 3 percent to 30 percent of hearing loss. This high prevalence rate may be related to genetic susceptibility from mitochondrial mutations in the 12S rRNA gene, comorbidity factors, or unregulated use of the medication. This study investigates the risk factors and prevalence of mtDNA mutations in serum from rural Nicaragua children with aminoglycoside-related hearing loss. STUDY DESIGN: Cross sectional study. SUBJECTS: Deaf children from rural Nicaragua. METHODS: Mitochondrial DNA isolated from serum collected from 31 deaf children with childhood or in utero exposure to gentamicin was amplified, sequenced, and analyzed for mutations in the 12S rRNA gene. RESULTS: No known pathologic mutations of the 12S rRNA gene were identified in this subpopulation of deaf children. In addition, patients with gentamicin exposure were often likely to have other comorbidity factors. CONCLUSION: These results suggest that genetic susceptibility is not a major factor in the high rate of gentamicin ototoxicity in this population sample. The high prevalence of gentamicin ototoxicty in this population is presumed to be due to unrestricted access to the drug.