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Asteroids and comets that cross Earth's orbit pose a credible risk of impact, with potentially severe disturbances to Earth and society. We propose an orbital planetary defense system capable of heating the surface of potentially hazardous objects to the vaporization point as a feasible approach to impact risk mitigation. We call the system DE-STAR, for Directed Energy System for Targeting of Asteroids and exploRation. The DESTAR is a modular-phased array of kilowatt class lasers powered by photovoltaic's. Modular design allows for incremental development, minimizing risk, and allowing for technological codevelopment. An orbiting structure would be developed in stages. The main objective of the DE-STAR is to use focused directed energy to raise the surface spot temperature to ~3000 K, sufficient to vaporize all known substances. Ejection of evaporated material creates a large reaction force that would alter an asteroid's orbit. The baseline system is a DESTAR 3 or 4 (1-to 10-km array) depending on the degree of protection desired. A DE-STAR 4 allows initial engagement beyond 1 AU with a spot temperature sufficient to completely evaporate up to 500-m diameter asteroids in 1 year. Small objects can be diverted with a DE-STAR 2 (100 m) while space debris is vaporized with a DE-STAR 1 (10 m). © 2014 The Authors.

Cochleosacculotomy is a surgical option for the treatment of incapacitating vertigo in elderly patients with Menière's disease. This procedure was performed in nine patients (mean age: 73 years) for control of vertigo and/or drop attacks. The average follow-up period was 29 months. Vertigo was controlled in eight of nine patients, but hearing worsened in all but one patient. No patient developed a transient increase in vertigo in the postoperative period. Cochleosacculotomy should be considered in elderly patients with recurrent vertigo and severe non-fluctuating sensorineural hearing loss who would otherwise be candidates for labyrinthectomy. [ABSTRACT FROM AUTHOR]

Objective: To describe the feasibility of managing hyponatremia patients under outpatient observation status in an academic medical center, and compare outcomes based on the use of an emergency department observation unit (EDOU)., Methods: This is a retrospective cohort study of emergency department hyponatremic patients managed in four hospitals within a large urban academic medical center over 27 months. All patients had an admit-to-observation order, ICD-10 codes for hyponatremia, and mild (130-135 mmol/L) to moderate (121-129 mmol/L) hyponatremia. Observation settings were divided into two groups: EDOU and Non-Observation Unit (NOU) inpatient beds. Severe hyponatremia (≤120 mmol/L) was excluded. Primary clinical outcomes were inpatient admit rate, length of stay (LOS), total direct cost, the rate of adverse events and 30-day recidivism., Results: 188 patients were managed as an observation patient, with 64 managed in an EDOU setting (age 74.0 yr, 70.3% female) and 124 managed in a NOU setting (age 71.5 yr, 64.5% female). Patient subgroups were similar in terms of presenting complaints, comorbidities, and medication histories. Initial and final sodium levels were similar between settings: EDOU (125.1 to 132.6 mmol/L) vs NOU (123.5 to 132.0 mmol/L). However, outcomes differed by setting for observation to inpatient admit rate (EDOU 28.1% vs NOU 37.9%, adjusted effect 0.70), overall length of stay (EDOU 19.2 h vs NOU 31.9 h; adjusted effect -10.5 h and total direct cost ($1230 vs $1531; adjusted effect -$167). EDOU sodium correction rates were faster (EDOU 0.44 mmol/L/h vs 0.24 mmol/L/h; adjusted effect 0.15 mmol/L/h) and 30-day recidivism rate was similar (EDOU 13% vs NOU 15%). There were no index visit deaths or intensive care unit admissions., Conclusion: Management of selected hyponatremia patients under observation status is feasible, with the EDOU setting demonstrating lower admit rates, shorter length of stay, and lower total direct costs with similar clinical outcomes., Competing Interests: Declaration of competing interest No conflicts of interest for all authors., (Copyright © 2024 Elsevier Inc. All rights reserved.)

This manuscript evaluates the technical feasibility of reusing coal ash in the formulation design of dense asphalt mixes. Physicochemical and mineralogical properties of fly and bottom ash matrixes prepared with coal ash were analyzed by scanning electron microscopy (SEM), X-Ray diffraction (XRD), semi-quantitative spectrometry by X-Ray fluorescence (XRF) and surface characterization by Nitrogen (N2) adsorption. Filler fractions under 0.075 mm with 6.0% in weight from an entirely gneissic aggregate gradation curve taken as reference were compared to identical mixes prepared with fly and bottom ashes individually and also to a combined sample with 3.0% of each ash type. Tests on compaction ability with gyratory shear press, resistance to action of water and to rutting were carried out to compare mechanical performance. The results indicate that both gneissic and coal ash fillers do not form dipoles of effective electric attractions to bituminous matrixes, resulting in inert and hydrophilic behavior regarding to action of water, respectively. Despite surface and morphologic characteristics underlying the mechanical performance of gneissic fillers, coal ash matrixes have shown, in general, good technical feasibility to be used in asphalt mixes.

The Patient Protection and Affordable Care Act of 2010 mandates a national comparative outcomes research project agenda. Comparative effectiveness research includes both clinical trials and observational studies and is facilitated by electronic health records. A national network of electronic health records will create a vast electronic data "warehouse" with exponential growth of observational data. High-quality associations will identify research topics for pragmatic clinical trials, and systematic reviews of clinical trials will provide optimal evidence-based medicine. Evidence-based medicine is the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients. Thus, health care reform will provide a robust environment for comparative effectiveness research, systematic reviews, and evidence-based medicine, and implementation of evidence-based medicine should lead to improved quality of care.

Objective: To describe nystagmus induced by cranial vibration in a case series of 8 patients with superior semicircular canal dehiscence., Design: Consecutive case series review., Setting: Tertiary vestibular center., Patients: Eight consecutive patients with computed tomographic confirmed superior semicircular canal dehiscence syndrome observed in the last 24 months., Procedure: Vertex, bilateral mastoid, and bilateral suboccipital cranial vibration were performed using 100 Hz. Vibration for 10 to 15 seconds on patients in the seated position during office evaluation for vestibular complaints. Nystagmus was monitored by infrared video oculography with digital recording., Results: All patients demonstrated distinct torsional/vertical vibration-induced nystagmus. Maximal recorded slow-phase velocity was 20 degrees/s. This was observed best with suboccipital vibration on the side of the dehiscence., Conclusion: Vibration-induced torsional/vertical nystagmus, observed best with ipsilateral suboccipital cranial vibration in the seated position, seems to be a sensitive screening test in the office setting for the presence of superior semicircular canal dehiscence.

Autoimmune sensorineural hearing loss (ASNHL) is the most common cause of sudden hearing loss in adults. Although autoimmune etiopathogenic events have long been suspected in ASNHL, inner ear-specific Ags capable of targeting T cell autoreactivity have not been identified in ASNHL. In this study, we show by ELISPOT analysis that compared with normal hearing age- and sex-matched control subjects, ASNHL patients have significantly higher frequencies of circulating T cells producing either IFN-gamma (p = 0.0001) or IL-5 (p = 0.03) in response to recombinant human cochlin, the most abundant inner ear protein. In some patients, cochlin responsiveness involved both CD4+ and CD8+ T cells whereas other patients showed cochlin responsiveness confined to CD8+ T cells. ASNHL patients also showed significantly elevated cochlin-specific serum Ab titers compared with both normal hearing age- and sex-matched control subjects and patients with noise- and/or age-related hearing loss (p < 0.05 at all dilutions tested through 1/2048). Our study is the first to show T cell responsiveness to an inner ear-specific protein in ASNHL patients, and implicates cochlin as a prominent target Ag for mediating autoimmune inner ear inflammation and hearing loss.

Objective: We analyzed pure-tone and speech audiometric results from a prospective trial of anti-inflammatory treatment of subjects with active autoimmune inner ear disease (AIED). We sought to characterize the pattern and size of the treatment effect as reflected in clinical audiometry and to identify audiometric predictors of response to steroid treatment of AIED., Subjects: Adult participants demonstrated clinically established criteria for AIED (n = 116). Eligibility required audiometric evidence of active AIED as indicated by idiopathic sensorineural hearing loss with threshold elevations within 3 months of enrollment., Methods: We evaluated audiometric changes after 4 weeks of treatment with pharmacologic doses (60 mg/day) of prednisone. We examined the relationship between audiometric pure-tone thresholds at baseline and changes in word intelligibility score (WIS) using parametric and nonparametric analyses. Magnitudes of change were assessed using independent or paired t-tests. Separate analyses were performed on subgroups that did or did not show improved WIS score with steroid treatment., Results: Overall mean pure-tone averages improved from baseline to closeout of prednisone treatment in better hearing ears from 52.4 to 48.3 dB (p < .0001). Mean WIS improved in the better ear from 71.4% to 78.1% (p < .0001). Of pure-tone measures, only the six-tone average showed significant correlation with both the absolute improvements in WIS and with the percentage change in WIS after treatment. Individual frequencies at baseline showed no significant relationship with changes in WIS score after treatment. In 69 (59.5%) of 116 subjects, WIS improved (range, 2-80%) in the better ear. In these subjects, the baseline pure-tone thresholds and pure-tone averages correlated significantly and positively with improvement in WIS., Conclusions: Steroid treatment in AIED-mediated hearing loss produce variable but significant hearing gains. Neither a focal, cochleotopic region of greatest vulnerability to AIED nor frequency-specific amenability to treatment were evident. We did observe that analysis of predictors and the degree of treatment effect vary with different approaches to measuring change in the WIS. Depending on the approach adopted, the size of the treatment effect may be greatest across intermediate hearing levels at baseline. These observations offer an audiometric database that may enable greater precision in judging clinically meaningful parameters for future studies of AIED treatment and other interventions for sensorineural hearing loss.

Objective: To review published literature regarding the use of intratympanic steroids in the treatment of Meniere's disease and sudden sensorineural hearing loss and to make recommendations regarding their use based on the literature review., Data Sources: Literature review from 1996 to 2003, PubMed, Medline Plus, and Web of Science., Study Selection: Retrospective case series and uncontrolled prospective cohort studies were the only types of studies available for review., Conclusion: On the basis of the available literature, a weak recommendation is made to use intratympanic steroid treatment of sudden hearing loss if oral steroid therapy fails or is contraindicated. The available studies regarding intratympanic steroid treatment of Meniere's disease and tinnitus are inadequate to answer the question of the efficacy of this treatment for these conditions. Higher quality studies are needed.

A retrospective review of 53 consecutive patients who underwent a retrosigmoid vestibular nerve section (VNS) or microvascular decompression (MVD) through a modified suboccipital craniectomy with a minimum follow-up of 2 years was performed. Technical modifications to the suboccipital craniectomy included a skin incision designed to avoid the lesser and greater occipital nerves; a small, 2-cm diameter craniectomy with no intradural drilling of bone; and a simplified closure to prevent muscle adhesion to dura without the need for cranioplasty. The presence, duration, and severity of postoperative headache were the primary outcome measures. Craniectomy-related complications, operative time, and length of hospital stay were also reviewed. The incidence of postoperative headache after suboccipital craniectomy was 7.5% at 3 months (4/53), 3.8% at 1 year (2/53), and 3.8% at 2 years (2/53). Complications related to craniectomy included cerebrospinal fluid leakage (5.7%), aseptic meningitis (1.9%), and superficial wound infection (1.9%). The mean operative time was 145 and 98 minutes for VNS and MVD, respectively. The mean hospital stay was 2.2 and 3.6 days for VNS and MVD, respectively. Technical modifications of suboccipital craniectomy during retrosigmoid VNS and MVD lowered the incidence of postoperative headache and craniectomy-related complications and had no adverse effect on operative time or length of hospital stay.

Autoimmune sensorineural hearing loss (ASNHL) is characterized typically by bilateral, rapidly progressive hearing loss that responds therapeutically to corticosteroid treatment. Despite its name, data implicating autoimmunity in the etiopathogenesis of ASNHL have been limited, and targeted self-antigens have not been identified. In the current study we show that the inner ear-specific proteins cochlin and beta-tectorin are capable of targeting experimental autoimmune hearing loss (EAHL) in mice. Five weeks after immunization of SWXJ mice with either Coch 131-150 or beta-tectorin 71-90, auditory brainstem responses (ABR) showed significant hearing loss at all frequencies tested. Flow cytometry analysis showed that each peptide selectively activated CD4(+) T cells with a proinflammatory Th1-like phenotype. T cell mediation of EAHL was determined by showing significantly increased ABR thresholds 6 weeks after adoptive transfer of peptide-activated CD4(+) T cells into naive SWXJ recipients. Immunocytochemical analysis showed that leukocytic infiltration of inner ear tissues coincided with onset of hearing loss. Our study provides a contemporary mouse model for clarifying our understanding of ASNHL and facilitating the development of novel effective treatments for this clinical entity. Moreover, our data provide experimental confirmation that ASNHL may be a T cell-mediated organ-specific autoimmune disorder of the inner ear.

Context: A number of therapies have been proposed for the long-term management of corticosteroid-responsive, rapidly progressive, bilateral sensorineural hearing loss (autoimmune inner ear disease [AIED]). Methotrexate has emerged as the benchmark agent but has not been rigorously evaluated for hearing improvement in patients with AIED., Objective: To assess the efficacy of long-term methotrexate in maintaining hearing improvements achieved with glucocorticoid (prednisone) therapy in patients with AIED., Design, Setting, and Participants: A randomized, double-blind, placebo-controlled trial conducted from February 3, 1998, to November 5, 2001, of 67 patients with rapidly progressive, bilateral sensorineural hearing loss at 10 tertiary care centers in the United States., Intervention: Randomization to either oral methotrexate (15 to 20 mg/wk; n = 33) or placebo (n = 34), in combination with an 18-week prednisone taper. Follow-up examinations, including audiometric evaluation, were performed at 4, 8, 12, 24, 36, 48, and 52 weeks, or until hearing loss was documented., Main Outcome Measure: Maintenance of hearing improvement achieved from prednisone treatment., Results: Sixty-seven patients (57.8%) enrolled in the prednisone challenge experienced hearing improvement. Twenty-five patients (37%) experienced hearing improvements in both ears. Of the individuals who reached study end points, 24 (80%) of 30 end points were because of measured hearing loss in the methotrexate group and 29 (93.5%) of 31 end points were because of measured hearing loss in the placebo group (P =.15). Methotrexate was no more effective than placebo in maintaining the hearing improvement achieved with prednisone treatment (hazard ratio, 1.31; 95% confidence interval, 0.79-2.17; P =.30)., Conclusion: Methotrexate does not appear to be effective in maintaining the hearing improvement achieved with prednisone therapy in patients with AIED.

Autoimmune sensorineural hearing loss (ASNHL) typically produces a bilateral rapidly progressive loss of hearing that may occur suddenly. The diagnosis is made by excluding ototoxicity, systemic disease, and other factors that mimic ASNHL and by showing a therapeutic response to corticosteroid treatment. Although autoantibodies and autoreactive T cells have been implicated in the etiopathogenesis of ASNHL, several central issues remain unresolved, including the relative prominence of B cell or T cell autoimmunity in the initiation and progression of ASNHL, the identity of the putative inner ear self-antigen(s) that target ASNHL, and the development and application of immunosuppressive therapies for preventing the progressive hearing loss which may be profound and require cochlear implantation. In this review, we will examine the seminal human and animal studies that have led to our current views regarding the autoimmune etiopathogenesis of ASNHL. In addition, we will address the need for developing an inner ear-specific mouse model for ASNHL that may define the stages leading to the development of ASNHL and may also provide new diagnostic markers and help develop novel and effective treatments for preventing progressive hearing loss in ASNHL.

Autoimmune sensorineural hearing loss (ASNHL) typically produces bilateral rapidly progressive loss of hearing over a few days or weeks, but may also produce sudden loss over a few hours. The diagnosis is made by excluding ototoxicity, systemic disease, and other factors that mimic ASNHL and by showing a therapeutic response to corticosteroid treatment. Antibody production and T-cell proliferative responses to inner ear antigens have been implicated in the etiopathogenesis of ASNHL. In the current study, we have extended these autoimmune investigations by determining the frequencies of inner ear specific IFN-gamma producing T cells in peripheral blood mononuclear cells (PBMC) from ASNHL patients and from age- and sex-matched control subjects. ELISPOT analysis showed that 25% of ASNHL patients have significant increased frequencies of inner ear specific IFN-gamma producing T cells in their PBMC. All control subjects were relatively unresponsive. Our results implicate inner ear specific IFN-gamma producing proinflammatory T cells in the pathogenesis of ASNHL.

Objective: To determine the surgical efficacy of a simplified retrosigmoid approach for vestibular nerve sectioning., Study Design: A retrospective analysis., Setting: Tertiary academic referral center., Patients: Twenty-eight consecutive patients who underwent vestibular nerve sectioning for intractable peripheral vestibular disorders., Intervention: All patients had a simplified retrosigmoid approach for vestibular nerve sectioning., Main Outcome Measures: Functional outcome after vestibular nerve sectioning was analyzed with respect to improvement in patient disability from vertigo and reduction in the frequency of definitive vertigo attacks. Resolution of lightheadedness provided an additional outcome measure. The incidence of surgical complications, including postoperative headache, was determined, and the operative time was reviewed., Results: Twenty-six patients (92.9%) had an improved functional level postoperatively, 21 (75.0%) had excellent improvement, 4 (14.3%) had significant improvement, 1 (3.6%) had limited improvement, and 2 (7.1%) had no change. No patient was worse postoperatively. Eighteen of 23 Ménière's patients (78.3%) had complete control of definitive vertigo attacks after vestibular nerve sectioning. Improvement in lightheadedness was seen in 23 patients (82.1%), 11 (39.3%) of whom reported complete resolution. Postoperative headache developed in 1 (3.6%) patient. No patients experienced infection, facial weakness, or leakage of cerebrospinal fluid. Mild hearing deterioration was seen in 2 patients (7.1%). The mean operative time was 76.3 minutes., Conclusion: With excellent efficacy, short operative time, and a low incidence of postoperative hearing loss or headache, this simplified retrosigmoid technique should be considered for vestibular nerve sectioning in patients with intractable peripheral vestibular disorders.

Involvement of autoimmune mechanisms in sudden-onset, rapidly progressive, bilateral inner ear disease is supported by the following evidence: (1) the inner ear contains immune cells and mediators (immunoglobulins); (2) animal models demonstrate inner ear damage after immunization with inner ear tissue; (3) experimental autoimmune inner ear disease appears to be transferable with sensitized T cells; (4) human SNHL can occur in the context of systemic immunologic disease; (5) SNHL can be improved by immunosuppressive therapy; and (6) patients with SNHL demonstrate elevated immune responses to inner ear proteins/tissue preparations. There are also several reasons, however, why the above inner ear disease cannot be termed "autoimmune": (1) in experimental models, inner ear damage may be produced during an in situ immune response to an irrelevant antigen; (2) histopathology is not yet extensive enough to confirm the role of immune cells and mediators in human disease; (3) immune reactivity to an organ-specific antigen associated with the inner ear has not yet been identified. At this time, therefore, clinical inner ear disease with evidence of immunologic involvement is termed "immune-mediated" rather than "autoimmune." IMIED is likely to represent a heterogeneous group of diseases with multifactorial causes but a common endpoint. Diagnosis is made primarily by clinical profile in association with laboratory testing to rule out neoplasia or infection. Investigational laboratory immunoassays for antibodies to inner ear proteins or hsp 70 appear to have promise for diagnosis or predicting clinical response to immunosuppressive treatment. Sensitivity and specificity of such assays have not yet been established.

Immune inner ear disease results in rapidly progressive, bilateral sensorineural hearing loss and is one of the few forms of sensorineural hearing loss that can be treated medically. The purpose of this study is to identify and preserve several populations of sensitized lymphocytes from patients with immune inner ear disease as a first step toward cloning autoreactive T cells, in order to study the pathogenesis of disease. Lymphocytes from four patients with high reactivity (stimulation index of 2.5 or greater) were placed in frozen storage. At 8 to 14 months they were thawed and restimulated. All four samples were viable. Two reacted again to inner ear homogenate, but with different intensities. Some lymphocytes sensitized to inner ear antigens can retain reactivity after frozen storage. This methodology may be useful to clone highly reactive T cells.

Immune sensorineural hearing loss is manifested in several systemic immune diseases. Although hearing loss has been previously documented in patients with Sjögren's syndrome (SS), the effect of SS on hearing is unclear. This prospective study was designed to assess the presence of hearing loss in 14 patients with SS and, if sensorineural hearing loss was present, to determine if the hearing loss was immune-mediated. Patients were evaluated with basic audiologic tests as well as for cellular immune inner ear reactivity as measured by the lymphocyte transformation test (LTT). Three patients had evidence of sensorineural hearing loss. Two patients had a positive LTT without evidence of sensorineural hearing loss. This preliminary study suggests that SS may not directly cause sensorineural hearing loss, immuno-mediated or otherwise.

Approximately 4000 new cases of sudden hearing loss (SHL) occur annually in the United States, and 15,000 annually worldwide, accounting for approximately 1% of all cases of SHL. Although prevalence studies do not necessarily distinguish between idiopathic and acquired SHL, most cases of spontaneous SHL have no identifiable cause. In this article, the authors assess the cause, history, diagnosis, and treatment of SHL.

Adenomatous lesions of the temporal bone represent a diverse group of neoplasms. At least three histopathologic patterns have been described: glandular; ribbon-like, or "festooning;" and aggressive papillary. Combinations of glandular and ribbon-like histologies in the same lesion are not uncommon. The glandular and ribbon-like histologies have been associated with carcinoid tumors, and the aggressive papillary tumor has been considered a separate entity. Recently, the endolymphatic sac has been proposed as the site of origin of the aggressive papillary lesions. Previous reports have described neuroendocrine properties with characteristics embracing the three histologic types. The authors postulate that the neural crest is the site of origin of this unusual group of neoplasms. Immunohistochemical analysis on the pathologic specimens of patients with adenomatous lesions of the temporal bone was performed to test this hypothesis. From 1975 to 1992 seven patients were treated at the Cleveland Clinic Foundation with a diagnosis of middle ear adenoma. A panel of special stains for neuroectodermal markers, including synaptophysin, chromogranin, neuron specific enolase, calcitonin, and serotonin was used on the paraffin-embedded formalin-fixed specimens. Three lesions were also evaluated by electron microscopy, all demonstrating dense core, intracytoplasmic granules. Three ribbon-like tumors were positive for synaptophysin and chromogranin, and two of these were positive for serotonin. One glandular tumor was positive for synaptophysin, and an aggressive papillary tumor was positive for synaptophysin and neuron specific enolase. An additional papillary tumor was referred following a third recurrence without accompanying immunohistochemical data. Cholesteatoma-like material was identified with a few glandular cells interspersed, all negative by immunohistochemical evaluation. The seventh specimen, initially diagnosed as papillary adenoma on light microscopy, was not studied by the aforementioned stains, and was later identified as a papilloma of sinonasal origin. The neural crest gives rise to pluripotential stem cells with widespread anatomic distribution, including the temporal bone. Because immunomarkers used in this study are specific for neuroectodermal differentiation, results suggest that temporal bone adenomas have neuroendocrine characteristics and could be derived from the specialized neuroectoderm of the neural crest.

This brief article presents general criteria for evaluating results of different operations for hearing, vertigo, and disability. Also reviewed are the 1985 guidelines of the Committee on Hearing and Equilibrium of the American Academy of Ophthalmology and Otolaryngology, which are currently being revised.

Members of the American Otological Society and the American Neurotology Society were polled regarding stapes surgery and reparative granuloma. Of 467 questionnaires, 176 (38%) were returned, and 319,410 stapes cases were statistically analyzed: 329 reparative granulomas were reported after stapedectomy (incidence = 0.1%) and 29 after stapedotomy (incidence = 0.07%); 77 surgeons reported having encountered at least one reparative granuloma; and 50 surgeons related the occurrence of a reparative granuloma to a specific graft material. Gelfoam was the most common graft material reported when a reparative granuloma was encountered, followed by fat, and vertigo was the most frequently reported presenting symptom. Reported operative techniques as well as manifestations, management, and outcome are discussed.

Immune inner ear disease is a relatively new and distinct clinical entity that produces unexplained, rapidly progressive, bilateral sensorineural hearing loss. The diagnosis is based on clinical manifestations, positive immune laboratory testing, and beneficial response to a trial of corticosteroids. Immune laboratory tests are used to confirm a presumptive clinical diagnosis. The two tests most commonly used are the lymphocyte transformation test and Western blot immune assay. The rationale behind these tests is presented, and the role they play in laboratory diagnosis of immune inner ear disease is discussed.

This study examines variability in facial movements in normal subjects using a new objective method of measuring facial movement, video microscaling. Video microscaling superimposes a computer-generated measuring scale over a video recorded image of facial movements. Distances moved are determined digitally. Eleven subjects were tested raising the eyebrows and smiling five times on two separate days. Test-retest, day-to-day, side-to-side, and intersubject variability were evaluated. Average variability was relatively low; however, some normal subjects exhibited considerable variability, particularly from day-to-day and from side-to-side. Because of this, a facial nerve grading system based solely on objective measurements of facial movements may be invalid. Video microscaling is a promising research technique.

Various surgical approaches to the cerebellopontine angle have been used for removal of acoustic neuromas. A retrolabyrinthine transtentorial approach has been developed that allows (1) access to the anterior cerebellopontine angle and all portions of the basilar artery, (2) extra dural retraction of the lateral sinus and cerebellum while avoiding the vein of Labbé, and (3) preservation of hearing. This approach allows good exposure of tumor and accurate visualization of cranial nerves. To avoid complications, control of spinal fluid is mandatory and great care must be taken to avoid injury of the cranial nerves. The retrolabyrinthine or translabyrinthine transtentorial approach enables skilled neurosurgeons and neurotologists to gain access to lesions that are located in areas difficult to approach.

Fewer stapes operations are available to train residents and to maintain individual competence. Most residents in the United States perform 0 to 10 cases during training, and produce results which are not as good as expert results, even with close supervision. After graduation, fewer cases are available to achieve expert results in private or academic practice. The authors' conclusions and recommendations are based on his own learning curve. Residents who have below average skills in middle ear surgery, and residents who do not wish to practice otology, should watch but not perform stapes surgery. Program directors, collectively or separately, should develop more formal guidelines for teaching stapes surgery during residency.

In this article, we present a case of bilateral perilymph fistulae. This entity is rare and always presents a diagnostic problem. Bilateral perilymph fistulae are more common in children and should be suspected when bilateral ear symptoms and congenital temporal bone radiographic anomalies are present. Previous trauma or barotrauma may be absent. When a patient manifests bilateral ear symptoms and a fistula has been identified and repaired in one ear, a second fistula should be suspected in the contralateral ear, especially if the fistula test is positive.

Bell's palsy is an acute unilateral weakness or paralysis of the face resulting from peripheral facial nerve dysfunction. While there is no readily identifiable cause, there is some recovery of function within 6 months. This article offers practical guidelines for diagnosing and treating Bell's palsy. These guidelines are based on the author's experience with 63 patients over the last 8 years. Physical examination should reveal diffuse nerve involvement, normal otoscopic findings, and no skin blebs or blisters and parotid masses. Other cranial nerve palsies may be present. Diagnostic testing should include basic audiometry if available, and computed tomography or magnetic resonance imaging scanning if paralysis is present. Facial photography is recommended. Topognostic testing is not helpful because it no longer guides the surgical approach, and prognostic tests are not necessary if the face is not paralyzed. The only sufficiently sensitive test to determine the need for possible surgery is electroneurography. Eye care is critical in all but the mildest cases, and steroids may also be helpful. Surgery is rarely needed and should consist only of middle fossa total decompression; simple decompression of the tympanic and mastoid segments is seldom helpful. The natural history of the disease and the limited role of surgery provide new guidelines for practical management of Bell's palsy.

A perilymph fistula is an abnormal communication between the inner ear fluids and the middle ear space. This article identifies areas of agreement in perilymph fistula management based upon 167 questionnaire responses from active surgeons of the American Otological Society and the American Neurotological Society. The average respondent performed 4.6 fistula explorations among 197 otologic surgeries (some of these were myringotomies) per year. The following statements represent areas of general agreement. The single most important feature of the history is previous trauma or barotrauma. At present no test can replace clinical judgment; however, despite sound judgment and sophisticated testing, it is very difficult to document the presence or absence of a fistula preoperatively. Most often the diagnosis is based on the total clinical picture: history, physical examination, and laboratory testing.

Previously, the authors reported that objective pulsatile tinnitus can be the major or only manifestation of benign intracranial hypertension. This report updates the authors' experience with 31 patients managed over the past 7 years. Benign intracranial hypertension should be suspected in all patients with pulsatile-objective tinnitus, especially when the patient is a young, obese female with headaches and/or visual disturbances. Papilledema and small ventricles or an empty sella on computerized tomography are almost diagnostic. The diagnosis is confirmed by elevated spinal fluid pressure on lumbar puncture. In such patients, angiography is not indicated. Furosemide and acetazolamide are very effective. Ligation of the internal jugular vein is contraindicated.

Pseudocyst of the auricle (benign idiopathic cystic chondromalacia) is rare. Only 20 cases have been previously reported in the literature. Our study retrospectively reviews 21 additional cases. We conclude that idiopathic cystic chondromalacia can occur in both sexes, in all races, and at any age. The differential diagnoses for idiopathic cystic chondromalacia are relapsing polychondritis and chondrodermatitis nodularis chronica helicis. Recurrence of idiopathic cystic chondromalacia is uncommon following adequate local treatment.

In a variety of structural forms, carbon possesses certain properties that render it suitable for implantation in the human body. This report analyzes biocompatibility of a new carbon-carbon prosthesis following long-term middle ear implantation in a prospective, controlled animal study. The prosthesis was placed in the left ear of 20 healthy guinea pigs and in the dorsal subcutaneous tissues for control. The right ear also served as control. Preoperative and postoperative auditory evoked potentials were recorded and compared. Samples of tissue from all three sites were evaluated at 3 and 6 months by light microscopy. The implants also were evaluated by scanning electron microscopy. Samples of lymph nodes, liver, spleen, and lungs also were examined. Fourteen animals (70%) demonstrated no change in auditory evoked potentials postoperatively. One animal developed unilateral dysfunction and three others developed bilateral dysfunction for unexplained reasons. No significant tissue destruction or inflammation of the tissues and no digestion or erosion of the implants were observed. No passage of carbon particles into the reticuloendothelial system was identified. These preliminary results suggest that this new carbon-carbon prosthesis may be biocompatible at 6 months follow-up in the guinea pig and encourage further investigation.

A previous study by the authors compared pathologic changes in the mouse sciatic nerve following prolonged continuous stimulation with either pulsed or direct current. The pulsed current stimulator was found as equally effective yet far safer than the direct current (DC) stimulator. In an attempt to reproduce more accurately the clinical setting, the Ear, Nose, and Throat Device Classification Panel of the Food and Drug Administration requested a prospective, controlled study of repeated DC stimulation at one or more sites along a peripheral motor nerve. Again, repetitive DC stimulation both at one site and at multiple sites of the same nerve produced significant myelin and axon degeneration. The authors conclude that even routine use of the DC stimulator carries with it the potential for permanent nerve damage and muscle paralysis.

Evoked potentials (EPs) have been used to detect auditory, visual, and somatosensory dysfunction. Evoked potentials are recorded by averaging an optimal number of responses (that are time-locked) to the same number of appropriate stimuli. Adequate stimulus levels and "minimal" response latency are necessary for recording evoked potentials. Vestibular evoked potentials have received considerably less attention because of the difficulty in providing appropriate stimuli, the relatively long latency of vestibular responses, and the adaptation of the vestibular system to repeated stimulation. Technological advances have made it possible to provide accurate stimuli by use of computer-controlled rotating chairs and computer-averaging procedures.

Electroneurography, an objective electrophysiologic measurement of a muscle compound action potential, is used to assess the integrity of a peripheral motor nerve. This paper describes how to perform electroneurography with particular attention to control of patient and instrumentation variables. Twenty-two normal adult subjects were tested in a balanced, designed experiment. The resultant average difference between the right and left halves of the face was not significant. The standard deviation of this difference was divided into three components: test-retest daily, and intersubject. The data suggest that the most significant source of error in electroneurography is test-retest variability (p less than 0.05) and that repeated and averaged measures on a given patient will increase the precision of the test. As further understanding and experience are gained, electroneurography measurements should be interpreted in light of clinical findings and more traditional tests.

Since 1981, 28 patients have been diagnosed with autoimmune inner ear disease. This preliminary, retrospective study reviews clinical and laboratory manifestations of autoimmune vestibular dysfunction. Sixteen of 28 patients presented with dizziness (7 vertigo, 8 lightheadedness, 1 ataxia). Twelve of these patients presented with Meniere's syndrome. Seven of 16 dizzy patients underwent formal vestibular testing. Five had reduced vestibular response in the involved ear(s); one patient had positional nystagmus only; and one had normal results. Of 17 patients with adequate follow-up, 11 presented with dizziness. Hearing improved and dizziness resolved in two patients following treatment. Hearing stabilized and dizziness resolved in two. Hearing stabilized but lightheadedness (without vertigo) persisted in five. Hearing was lost and oscillopsia resulted in two patients. Preliminary conclusions are vestibular dysfunction in autoimmune inner ear disease is nonspecific; bilateral vestibular dysfunction is more common; Meniere's syndrome is relatively common; medical management usually is helpful; surgery at this time does not seem appropriate; vestibular treatment results tend to parallel auditory treatment results.