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Objectives/Hypothesis: To assess whether practice on a virtual-reality (VR) temporal bone simulator improves acquisition of technical skills in mastoid surgery. Study Design: Prospective blinded study. Methods: Using a previously validated objective structured assessment of technical skills (OSATS) tool, performance was assessed in 12 residents for two tasks of cortical mastoidectomy: 1) identifying and defining the tegmen and 2) defining the sigmoid sinus and sinodural angle. These surgical tasks were chosen as key steps in mastoid dissection because they were of intermediate complexity. Videos of virtual dissections were captured at baseline and again after practicing each task four to six times. Results: OSATS scores for the tegmen task increased from 2.125 ± 1.25 to 3.1 ± 0.85 ( P = .026), whereas for the sigmoid task scores increased from 2 ± 0.45 to 2.75 ± 1.125 ( P = .0098). The time to complete the tasks decreased from 8.37 ± 4.78 minutes to 5.39 ± 3.06 minutes ( P = .018) for the tegmen task and from 8.99 ± 6.7 minutes to 8.68 ± 5.98 minutes ( P = .594) for the sigmoid task. There was a decline in number of injuries from 0.5 ± 1.5 to 0 ± 0.5 ( P = .594) for the tegmen task and from 2.5 ± 4 to 0.5 ± 1 ( P = .029) for the sigmoid task. Conclusions: Technical skills in mastoidectomy surgery can be acquired during even brief practice on the VR temporal bone simulator. It is anticipated that longer periods of practice presented within the fundamentals of comprehensive curriculum will facilitate procedural learning. Further studies are required to elucidate evidence of transference of these skills to the operating room and to procedures of greater complexity. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to evaluate disparities in socioeconomic status and healthcare utilization in hearing-impaired children using a nationally representative sample. Study Design: Cross-sectional analysis of stacked data from the 1997 to 2003 National Health Interview Survey, a voluntary U.S. household survey of the National Center for Health Statistics. Methods: Children were grouped according to three levels of hearing ability based on parental response to perceived hearing status. v2 and analysis of variance (ANOVA) models tested the association of individual sociodemographic variables with hearing status. Multivariate regression analyses examined the association of hearing impairment with family income, poverty status, and utilization of routine and specialty health services. Results: The total sample consisted of 76,012 children, of whom 2.6% had some hearing loss and 0.43% had marked hearing loss. Families of hearing-impaired children were more likely to report poorer health status, have Medicaid, live in single- mother households, and live below the poverty level (P < .01). After adjusting for confounders, children with mild and marked hearing impairment were less likely to afford prescription medications (odds ratio [OR] = 1.89, 95% confidence interval [CI], 1.44-2.48 [mild]; OR = 2.72, 95% CI, 1.73-4.29 [marked]) and less likely to have access to mental health services (OR = 3.26, 95% CI, 2.41-4.69 [mild]; OR = 2.62, 95% CI, 1.34-5.12 [marked]) or dental services (OR = 1.65, 95% CI, 1.36-2.02 [mild]; OR = 1.62, 95% CI, 1.09-2.41 [marked]). No difference was identified for access to routine/sick health services. Conclusions: Compared with families of children without hearing loss, families of hearing-impaired children live closer to the poverty level and utilize some medical services with less frequency. Further identification of causal relationships between familial socioeconomic status and childhood hearing loss may help direct policy initiatives designed to mitigate healthcare disparities and improve access to services for hearing-impaired children. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: To assess trends in the management of unilateral vestibular schwannomas over an 11-year period and to identify disease- and provider-related influences. Study Design: Retrospective chart review. Methods: Subjects presented to the Department of Otolaryngology-Head and Neck Surgery and the Department of Neurosurgery for management of unilateral vestibular schwannoma from 1997 through 2007, with at least two visits within the first year of presentation. The proportion of patients for whom initial management consisted of observation, surgical resection, or radiation therapy was determined, and the relative influence of study year, patient age, hearing status, and tumor size was analyzed. Results: Over the study period there was an increase in the proportion of cases that were observed with follow-up scanning (10.5% to 28.0%) and recommended for radiation (0% to 4.0%), whereas the proportion of operated cases declined (89.5% to 68.0%). There were no changes in mean age or hearing status at diagnosis, but mean tumor size declined significantly. Compared to those undergoing surgery, patients choosing observation and radiation therapy were on average 11.7 and 4.5 years older, respectively. Tumors that were surgically removed were on average 11.6 mm larger than those that were observed. The increasing frequency over time of observation relative to surgery was significant even after controlling for age, hearing status, and tumor size. Conclusions: Among patients managed by our center, there has been a significant shift in management of vestibular schwannomas over the last decade, with increasing tendency towards observation. This trend implies changing provider philosophy and patient expectations. Laryngoscope, 2010 [ABSTRACT FROM AUTHOR]

Objectives: As stereotactic radiation has emerged as a treatment option for acoustic neuromas, cases that require surgical salvage after unsuccessful radiation have emerged. We present a comparison of the technical challenges faced by the surgeons in the treatment of irradiated versus nonirradiated acoustic neuromas. Study Design: Matched case-control series. Methods: We identified nine patients with acoustic neuromas that required surgical resection after radiation therapy. Cases were performed with suboccipital and translabyrinthine approaches. Nine nonirradiated case-control subjects matched for age, sex, tumor size, and surgical approach were identified for purposes of general comparison. Operative findings and outcomes were compared for the two groups. Results: Surgical removal was found to be significantly more difficult after radiation therapy because of increased fibrosis and adhesion to adjacent nervous structures, particularly at the porus acousticus. Excessive scarring hindered identification of the facial nerve and added uncertainty as to the completeness of tumor removal. Decompression of the internal auditory canal (IAC) dura and resection of neoplasm in the IAC before cerebellopontine angle dissection was required for facial nerve identification. Operative time was significantly longer for irradiated cases, and facial nerve outcomes tended to be poorer, particularly when facial nerve dysfunction prompted the salvage procedure. Conclusions: Surgical salvage of acoustic neuromas after radiation therapy is feasible, but it presents technical challenges beyond that associated with primary surgical therapy. Poorer outcomes of postoperative cranial nerve status were caused primarily by anatomic changes at the nerve/tumor interface. As surgical experience with the irradiated acoustic neuroma grows, operative observations should be incorporated into the counsel provided to patients with acoustic neuromas as they weigh different management options. [ABSTRACT FROM AUTHOR]

Objectives To assess the impact of cochlear implantation on quality of life changes in older adults aged 50 years and above. Study Design Retrospective study by questionnaire and chart review. Methods Forty-seven patients aged 50 to 80 years (mean age, 63.4 y [SD = 8.6 y]), who have multiple-channel cochlear implants received at The Listening Center at Johns Hopkins Hospital, completed the Ontario Health Utilities Index Mark 3 survey and a questionnaire on quality of life changes. Health utility scores before and after cochlear implantation were measured, and audiologic data before implantation and at 6 months and 1 year after implantation were analyzed. Results Cochlear implantation in older adults is associated with a mean gain in health utility( P <.0001) of 0.24 (SD = 0.33), which corresponds to a favorable cost-utility of $9530 per quality-adjusted life-year. Improvements in hearing and emotional health attributes were primarily responsible for this increase in health-related quality of life measure. There was a significant increase in speech perception scores at 6 months after surgery ( P <.0001 for both CID sentence and monosyllabic word tests) and a strong correlation between the magnitude of health utility gains and the postoperative increase in speech perception scores ( r = 0.45, P <.05). Conclusions Cochlear implants have a significant impact on the quality of life of older deaf patients, and are a cost-effective intervention in this population. Improvements in speech perception are predictive of gains in health-related quality of life and associated emotional benefits after cochlear implantation. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis Transtympanic electrocochleography (t-ECOG) is a sensitive diagnostic instrument used for Meniere's disease. It is sensitive by virtue of the recording electrode's position on the promontory of the cochlea where the signals are generated. There is concern about the invasive nature of t-ECOG in comparison to extratympanic recording techniques. The purpose of this study was to examine the safety issues, complications, and patient experience with t-ECOG. Study Design Observational study utilizing retrospective chart review and patient survey. Methods The medical records of 205 patients who underwent t-ECOG were reviewed for complications. Complications included persistent tympanic membrane perforation, hearing loss, otitis media, otitis externa, ear canal injury, hemotympanum, and pain. An additional 36 patients undergoing t-ECOG were surveyed on subjective measures such as pain during topical anesthesia of the tympanic membrane, during transtympanic placement of the needle electrode, and during the test procedure and overall experience with t-ECOG. Results There was one case of a nonhealed, persistent perforation in the setting of acute otitis media directly as a result of t-ECOG. Two patients developed otitis media, and three patients had ear pain for up to 5 days. All 36 patients felt the procedure to be tolerable with minimal discomfort. Conclusions Transtympanic electrocochleography may be performed with good patient acceptance and infrequent complications. [ABSTRACT FROM AUTHOR]

Hypothesis: Sensorineural hearing loss may be associated with altered patterns of neuronal connections within the central auditory pathway. Study Design: The cat auditory system was used to address the relative importance of impulse traffic within the auditory nerve in maintaining central nervous system connections. Methods: Acute, unilateral deafness was induced by tetrodotoxin intoxication of cochlear hair cells. Analysis focused on the structural patterns of contact between auditory nerve endings called end bulbs of Held and their target neurons. Specifically, end bulb morphology and target cell size within the cochlear nucleus were examined. Highly specialized synaptic contacts at this junction provide a powerful site for study. Results: The principal finding was that abolished activity in the auditory nerve caused nerve endings to assume a different shape, typified by more branching and smaller terminal swellings. The new shape is one typically associated with only a subpopulation of fibers in normal-hearing cats-those exhibiting a high-threshold, low-spontaneous activity profile. This result implies that abolished activity alters patterns of nerve fiber contact with second-order neurons. Tetrodotoxin produced differential effects on subpopulations of target neurons within the brain-stem and is interpretable on the basis of 'weighing' synaptic inputs. Second-order neurons that receive large axosomatic inputs from their parent fiber were significantly smaller than neurons that receive small, axodendritic terminals. Thus, attenuated auditory activity may produce differential effects across the auditory pathway, thereby disrupting the normal balance of inputs into synaptic stations. Conclusions: Impulse traffic is a critical factor in the interaction between the ear and central auditory stations and appears necessary for the maintenance of key synapses. As hearing disorders with impaired comprehension may be modeled by studies of auditory deafferentation, these observations extend the possibility that changes in central neuronal connections underlie reduced capabilities for processing restored auditory input. [ABSTRACT FROM AUTHOR]

Three hundred ninety-seven patients with 407 cutaneous malignancies of the auricle, periauricular region, and cartilaginous external ear canal were reviewed. Tumors were most commonly located in the preauricular and postauricu-lar regions, followed by the helix, concha, antihelix, and ear canal. All lesions were excised with Mohs microscopic control of margins. For lesions requiring lateral temporal bone resection, an adaptation of fresh-tissue microscopic control was used to analyze deep and anterior margins suspected of harboring residual tumor. Two-year minimum follow-up of 229 patients with periauricular and auricular tumors (N = 231 tumors) and 14 patients with cartilaginous ear canal tumors (N = 14 tumors) revealed recurrence rates of 6.9% and 14.3%, respectively. Recurrences were most common in cases of large tumors (>2.5 cm), basal cell carcinomas with morphea elements, and multiply recurrent lesions. We conclude that Mohs surgery is comparatively effective, though not uniformly curative, and can be adapted to supplement excision of large tumors in these regions. [ABSTRACT FROM AUTHOR]

The presence of immune-mediated hearing loss was investigated in an animal model. Eight guinea pigs and four mice underwent immunizations with a preparation of chick or guinea pig cochlear tissue and Freund's adjuvant. Hearing thresholds were monitored by auditory brainstem response (ABR) testing over a 5-week period after immunization. The serum and temporal bones of test and control animals were then examined using an enzyme-linked im-munosorbent assay (ELISA), immunocytochemical, and his-tological techniques. Hearing loss of 20 dB or greater occurred in eight animals. ELISA demonstrated antibodies to cochlear antigens in the sera of all test animals. Immunocytochemistry revealed immunostaining of hair cell stereocilia in the organ of Corti and saccule. Endolymphatic hydrops, and organ of Corti degeneration was observed in the temporal bones of three animals. This study provides evidence to suggest that cross-species immunization with cochlear antigens might produce a humoral response that can be associeted with inner ear pathologic change and sensorineural hearing lose. [ABSTRACT FROM AUTHOR]

The cochlear prosthesis is not applicable to patients who lack an implantable cochlea or an intact vestibulocochlear nerve. Direct electrical stimulation of the cochlear nucleus (CN) of the brain stem might provide a method for auditory rehabilitation of these patients. A penetrating CN electrode has been developed and tissue tolerance to this device demonstrated. This study was undertaken to evaluate metabolic activation of central nervous system (CNS) auditory tracts produced by such implants. Regional cerebral glucose use resulting from CN stimulation was estimated in a series of chronically implanted guinea pigs with the use of [14C]−2-deoxyglucose (2-DG). Enhanced 2-DG uptake was observed in structures of the auditory tract. The activation of central auditory structures achieved with CN stimulation was similar to that produced by acoustic stimulation and by electrical stimulation of the modiolar portion of the auditory nerve in control groups. An interesting banding pattern was observed in the inferior colliculus following CN stimulation, as previously described with acoustic stimulation. This study demonstrates that functional metabolic activation of central auditory pathways can be achieved with a penetrating CNS auditory prosthesis. [ABSTRACT FROM AUTHOR]

Auditory brainstem response testing has been a major breakthrough in audiologic screening for acoustic neuroma because of its high degree of sensitivity. Although it is not uncommon for other cerebellopontine angle masses to present with normal ABR findings, reports of eighth nerve tumors with false-negative auditory brainstem response tests are quite rare. A series of 120 acoustic neuromas resected at the University of Michigan was reviewed and revealed two such patients. These two patients presented with asymmetric sensorineural hearing loss and unilateral tinnitus and were found to have completely normal auditory brainstem response. The diagnosis of acoustic neuroma would have been delayed if a comprehensive evaluation had not been pursued. [ABSTRACT FROM AUTHOR]

Current techniques for ossicular reconstruction include ossicular autografts and homografts, and plastic and ceramic prostheses. Experimental testing of ceramic materials has led to the development of a nonporous, bioactive form of glass ceramic (Ceravital) for tympanoplastic reconstruction. To determine the clinical usefulness of these implants, Ceravital ossicular reconstructions were evaluated in 37 patients treated at the University of Michigan Medical Center during an 18-month period. Thirty-two patients (86%) with chronic ear disease underwent Ceravital ossicular reconstruction with tympanoplasty with or without mastoidectomy. Five other patients (14%) underwent ossicular reconstruction-2 for congenital anomalies, 2 for temporal bone trauma, and 1 patient for glomus tympanicum removal. Patient follow-up ranged from 2.2 to 3.8 years, with a mean follow-up period of 2.9 years. Prosthesis extrusion occurred in one case (3%). Mean preoperative and postoperative (2-year) pure tone air-bone gaps were 41.6 dB and 21.3 dB, respectively. Hearing was improved in 35 of 37 patients (95%). Postoperative pure tone air-bone gap was closed to 20 dB or less in 23 patients (62%). Hearing gains were greater with partial rather than total reconstructions (p=0.14) and significantly greater with intact canal wall rather than canal wall down tympanoplasties ( p<0.05). Initial results obtained with the Ceravital ossicular prosthesis compare favorably with those obtained using other methods of alloplastic reconstruction. These preliminary data suggest that Ceravital is an effective alternative prosthetic material for ossicular reconstruction. [ABSTRACT FROM AUTHOR]

Preservation of the facial nerve during acoustic neuroma resection may be enhanced by the use of intraoperative electrical stimulation. Although stimulation of the extratemporal facial nerve is an effective and established procedure, anatomic differences of the intradural facial nerve and its microenvironment demand more exacting stimulus protocols. The absence of epineurium may make the intradural nerve more susceptible to mechanical or electrical trauma while intermittent pooling of cerebrospinal fluid (CSF) at the cerebellopontine angle may shunt current away from nerve. Four stimulus configurations were examined under varying conditions simulating CSF pooling. The results indicated that: 1. insulation of stimulating electrodes prevents CSF current shunting and allows utilization of a constant current source, and 2. monopolar and bipolar configurations demonstrate significantly different electrical characteristics which may be employed selectively based upon specific clinical goals. [ABSTRACT FROM AUTHOR]

Although cochlear implants now regularly achieve gratifying results, traditional intrascalar implants have certain limitations. Extraluminal implants may offset some of these problems by accessing neurons subserving a wider tonotopic range, avoiding intracochlear insertion trauma, and offering alternatives when cochlear obliteration is present. We have investigated the utility of a lateral cochlear wall implant in a normal-hearing cat model with implants at the middle and basal turns, and found successful activation of the auditory nerve at thresholds of 28.1 and 40.6 microA, respectively. No adventitial stimulation of the facial nerve was noted within the dynamic range. Maximum responsiveness was observed with implants of the middle turn of the cochlea, an area that is not reliably approached with current intrascalar implants. These observations support and extend prior observations of the feasibility of extraluminal stimulation of the auditory nerve. [ABSTRACT FROM AUTHOR]

Cost utility analysis is a method of cost-effectiveness analysis which provides results in terms of cost per quality-adjusted life-year (QALY). Cost utility for the multichannel cochlear implant was calculated using Ontario Health Utilities Index data from 229 Nucleus 22-channel implant users and 32 cochlear implant candidates awaiting surgery. The health utility of the implanted group was greater than that of the candidate group by 0.204 ( P<.0001). Use of this figure in a cost utility calculation indicates that cochlear implantation costs approximately$15,928 per QALY provided. Sensitivity analysis, a technique which systematically varies the assumptions underlying the calculations, suggests a range for the true value of between $12,000 and $30,000. This compares very favorably with other medical interventions. It is concluded that profound hearing loss has a significant effect on quality of life, and measurement of the changes that result from cochlear implant use indicates that this technology provides significant improvements and is quite cost-effective. Laryngoscope, 106:816-821, 1996 [ABSTRACT FROM AUTHOR]

The goal of this work was to evaluate, using autoradiographic techniques, the effects of variable periods of deafness on resting and evoked metabolic activity in central auditory structures elicited by direct electrical cochlear nucleus (CN) stimulation. Thirty-five pigmented guinea pigs, divided into five groups, underwent acute implantation of bipolar electrodes in the CN. One group was not deafened and served as hearing controls. The other four groups were deafened using an established protocol of sequential kanamycin/ethacrynic acid treatment and were tested at 4 weeks, 9 weeks, 16 weeks, and 15 months after deafening. Threshold currents for eliciting evoked middle latency responses (EMLRs) with direct CN stimulation were not significantly different between hearing and deafened groups. Autoradiographic data showed progressive reduction of the evoked metabolic response with incremental periods of deafferentation. Nevertheless, central auditory structures remained responsive to direct electrical stimulation of the CN. These data indicate that direct CN stimulation remains capable of activating the auditory tract despite prolonged periods of deafness. [ABSTRACT FROM AUTHOR]

The purpose of our study is to identify the potential roles of a virtual reality (VR) temporal bone simulator in the Otolaryngology residency program. Study Design: Cross-sectional educational design Methods: Five residents ranging from PGY-1 to PGY-4 were evaluated at three settings: 1) Virtual reality temporal bone simulator, 2) Temporal bone laboratory 3) Operating room. Using a previously validated checklist for mastoidectomy, faculty evaluated the residents for the following tasks: 1) Identification and definition of tegmen 2) Definition of sigmoid sinus and sino-dural angle. 3) Use of drill and 4) Overall surgical performance. The evaluations on virtual reality temporal bone simulator were then compared with the evaluations conducted in the operating room and the temporal bone laboratory. Results: The mean total score obtained for residents on VR temporal bone simulator was 2.54±0.75, 3.13±0.55 for OR, and 2.18±0.29 for temporal bone laboratory. The mean total score obtained for all settings among Otology 1 was 2.27±0.72, and for Otology 2 was 2.70±0.68. Conclusion: The surgical performance on the VR temporal bone simulator is concordant with the temporal bone laboratory performance, which provides an indirect evidence of transferability of surgical skills to the OR. VR simulator can assist in learning technical skills for mastoidectomy procedure and attain surgical competency at a faster rate. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: The purpose of our study was to explore factors that might influence the trajectories in residents' learning curves of surgical performance in the mastoidectomy procedure. Study Design: Retrospective-cohort study. Methods: Mastoidectomy evaluations based on a previously validated task-based checklist were obtained for nine residents from post-graduate year (PGY) 2 and 3 over a period of 3 years. Average scores were measured over time and learning curves were generated using scatter plots and non-parametric smoothing techniques. A 5-item survey was conducted to explore various residents' related characteristics such as interest. Results: Residents with interest level of 4 in Otology demonstrated a better overall average scores and learning curves compared to those with an interest level of 2. After adjusting for time of assessment, otology level, interest in otology, and time spent in the temporal bone laboratory, on average, those residents who attended an extra session in the laboratory had 0.04 higher average score (95% CI from 0.01 to 0.07, p-value=0.004). Conclusions: Residents with higher level of interest in the Otology specialty demonstrated better average scores compared to other residents. Moreover, residents with more attendances at temporal bone course sessions had better average assessment scores. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: To determine the feasibility, validity, and reliability of an evaluation tool for the assessment of competency in mastoid surgery. This study tests the hypothesis that residents of dissimilar training levels differ in their technical performance as measured by this tool., Study Design: Cross-sectional validation study., Methods: Two or more faculty otolaryngologists evaluated each resident performing a cortical mastoidectomy on a cadaveric temporal bone. Performance was rated using global and checklist components of a mastoidectomy assessment tool., Results: Fifteen internal and external faculty members evaluated 23 residents over 3 years resulting in 118 evaluations. Construct validity was observed as scores increased with clinical training year. These differences were greater for more complex tasks. There was a percentage agreement of 78.5% between evaluator pairs in the determination of pass (score 3-5) versus fail (score 1-2) for the checklist instrument, and an agreement of 74.4% for the global instrument. Although agreement was lower for the exact score on a scale of 1 to 5, differences of 1 or less occurred in over 80% of evaluator pairs. Regression analysis confirmed faculty perception that sharpening of the posterior external auditory canal cortex and opening of the antrum from posterior to anterior are strong predictors of overall surgical performance., Conclusions: Our results indicate that the tool we have developed is a feasible, valid, and reliable instrument for the assessment of competency in mastoidectomy. The instrument can be used to provide formative feedback and to identify procedural tasks for which additional training may be necessary.