Economic Burden of Hearing Loss for the U.S. Military: A Proposed Framework for Estimation.

The goal of this multiphased research is to develop methods to comprehensively determine the economic impact of hearing impairment and noise-induced hearing injury among active duty U.S. Service Members. Several steps were undertaken to develop a framework and model for economic burden analysis: (1) a literature review identifying studies reporting the cost of health conditions and injuries in the Department of Defense, (2) consultation with a panel of subject matter experts who reviewed these cost items, and (3) discussions with DoD data stewards and review of relevant data dictionaries and databases. A Markov model was developed to represent the cumulative economic effect of events along the career span, such as retraining after hearing impairment and injury, by synthesizing inputs from various sources. The model, as developed and proposed in this study, will be a valuable decision-making tool for the DoD to identify high-risk groups, take proactive measures, and develop focused education, customized equipping, and return-to-duty and reintegration programs, thereby maximizing the retention of skilled, experienced, and mission-ready Service Members.

The impact of hearing impairment and noise-induced hearing injury on quality of life in the active-duty military population: challenges to the study of this issue.

The objectives of this research were to 1) summarize the available evidence on the impact of hearing loss on quality of life (QOL) among U.S. active-duty service members, 2) describe the QOL instruments that have been used to quantify the impact of hearing loss on quality of life, 3) examine national population-level secondary databases and report on their utility for studying the impact of hearing loss on QOL among active-duty service members, and 4) provide recommendations for future studies that seek to quantify the impact of hearing loss in this population. There is a lack of literature that addresses the intersection of hearing impairment, the military population, and quality of life measures. For audiological research, U.S. military personnel offer a unique research population, as they are exposed to noise levels and blast environments that are highly unusual in civilian work settings and can serve as a model population for studying the impact on QOL associated with these conditions. Our team recommends conducting a study on the active-duty service member population using a measurement instrument suitable for determining decreases in QOL specifically due to hearing loss.

Anaplastic large-cell lymphoma presenting as a nasopharyngeal mass and cervical lymphadenopathy.

Cervical lymphadenopathy in adults has a broad differential diagnosis, including bacterial and viral infections, Kikuchi-Fujimoto disease, systemic lupus erythematosus, and various neoplasms. Many of its etiologies share similar symptomatology and presentations, which complicates the diagnosis. A thorough history and a comprehensive physical examination, to include nasopharyngoscopy and imaging as indicated by the specific case, are key to determining the origin of the lymphadenopathy and to avoid a missed or delayed diagnosis. Based on our review of the literature, we present the second reported case of anaplastic lymphoma kinase-positive anaplastic large-cell lymphoma presenting in an adult with an obstructing adenoid/nasopharyngeal mass and lymphadenopathy. The mass, which occurred in a 19-year-old woman of Asian descent, caused nasal airway obstruction in the setting of cervical lymphadenopathy that was initially ascribed to mononucleosis.

The Department of Defense Epidemiologic and Economic Burden of Hearing Loss study.

Although studies have examined the relation between military-related noise and hearing, comprehensive data to calculate rates of hearing loss across all Services and to determine economic impact are lacking. The goal of the multiphase Department of Defense (DoD) Epidemiologic and Economic Burden of Hearing Loss (DEEBoHL) project is to examine rates of hearing impairment and noise-induced hearing injury, relevant noise exposures, and to determine the economic burden of these outcomes to the DoD and Service Members. The DoD Hearing Center of Excellence is supporting the following Phase I specific aims, among active duty Service Members to (1) calculate rates of hearing impairment and noise-induced hearing injury, and (2) develop a framework for the DoD to conduct comprehensive economic burden studies for hearing impairment and noise-induced hearing injury. The study is led by a multidisciplinary team from The University of Texas School of Public Health, The University of Texas Health Science Center at San Antonio, and The Geneva Foundation, with guidance from experts who make up the study advisory board. In this article, we focus on an overview of the DEEBoHL study, the methods for the first aim of this effort, and describe future plans for the study.

Three-dimensional reproducibility of natural head position.

INTRODUCTION: Although natural head position has proven to be reliable in the sagittal plane, with an increasing interest in 3-dimensional craniofacial analysis, a determination of its reproducibility in the coronal and axial planes is essential. This study was designed to evaluate the reproducibility of natural head position over time in the sagittal, coronal, and axial planes of space with 3-dimensional imaging. METHODS: Three-dimensional photographs were taken of 28 adult volunteers (ages, 18-40 years) in natural head position at 5 times: baseline, 4 hours, 8 hours, 24 hours, and 1 week. Using the true vertical and horizontal laser lines projected in an iCAT cone-beam computed tomography machine (Imaging Sciences International, Hatfield, Pa) for orientation, we recorded references for natural head position on the patient's face with semipermanent markers. By using a 3-dimensional camera system, photographs were taken at each time point to capture the orientation of the reference points. By superimposing each of the 5 photographs on stable anatomic surfaces, changes in the position of the markers were recorded and assessed for parallelism by using 3dMDvultus (3dMD, Atlanta, Ga) and software (Dolphin Imaging & Management Solutions, Chatsworth, Calif). RESULTS: No statistically significant differences were observed between the 5 time points in any of the 3 planes of space. However, a statistically significant difference was observed between the mean angular deviations of 3 reference planes, with a hierarchy of natural head position reproducibility established as coronal > axial > sagittal. CONCLUSIONS: Within the parameters of this study, natural head position was found to be reproducible in the sagittal, coronal, and axial planes of space. The coronal plane had the least variation over time, followed by the axial and sagittal planes.

Growth inhibitory and anti-tumour activities of OSU-03012, a novel PDK-1 inhibitor, on vestibular schwannoma and malignant schwannoma cells.

BACKGROUND: Vestibular schwannomas (VS) frequently express high levels of activated AKT. Small-molecule inhibitors of AKT signalling may have therapeutic potential in suppressing the growth of benign VS and malignant schwannomas. METHOD: Primary VS and Schwann cells, human malignant schwannoma HMS-97 cells and mouse Nf2(-/-) Schwann cells and schwannoma cells were prepared to investigate the growth inhibitory and anti-tumour activities of OSU-03012, a celecoxib-derived small-molecule inhibitor of phosphoinositide-dependent kinase-1. Cell proliferation assays, apoptosis, Western blot, in vivo xenograft analysis using SCID mice and immunohistochemistry were performed. RESULTS: OSU-03012 inhibited cell proliferation more effectively in both VS and HMS-97 cells than in normal human Schwann cells. The IC5) of OSU-03012 at 48h was approximately 3.1 microM for VS cells and 2.6 microM for HMS-97 cells, compared with the IC(50) of greater than 12 microM for human Schwann cells. Similarly, mouse Nf2(-/-) schwannoma and Nf2(-/-) Schwann cells were more sensitive to growth inhibition by OSU-03012 than wild-type mouse Schwann cells and mouse schwannoma cells established from transgenic mice carrying the NF2 promoter-driven SV40 T-antigen gene. Like VS cells, malignant schwannoma HMS-97 cells expressed high levels of activated AKT. OSU-03012 induced apoptosis in both VS and HMS-97 cells and caused a marked reduction of AKT phosphorylation at both the Ser-308 and Thr-473 sites in a dose-dependent manner. In vivo xenograft analysis showed that OSU-03012 was well tolerated and inhibited the growth of HMS-97 schwannoma xenografts by 55% after 9 weeks of oral treatment. The anti-tumour activity correlated with reduced AKT phosphorylation. CONCLUSION: OSU-03012 is a potential chemotherapeutic agent for VS and malignant schwannomas.

Molecular studies of vestibular schwannomas: a review.

PURPOSE OF REVIEW: To summarize advances in understanding the molecular biology of vestibular schwannomas over the past year. RECENT FINDINGS: The role of the neurofibromatosis type 2 protein, denoted as merlin or schwannomin, in embryonic development, cellular adherence, and in cell proliferation has become better elucidated in the past year. Likewise, the role of merlin in Schwann cell-axon interaction has been studied. Additionally, two comprehensive analyses of the spectrum of human neurofibromatosis type 2 mutations have been compiled which make up a valuable resource in understanding critical regions of the neurofibromatosis type 2 gene. Neurofibromatosis type 2 screening guidelines for young patients with solitary vestibular schwannomas have been published. The role of electromagnetic radiation via cellular and portable telephones as a predisposing factor to vestibular schwannoma formation has also been the topic of several studies. Based on increased knowledge of the pathways in which merlin functions and the available transgenic and xenograft mouse models, preliminary data regarding directed pharmacotherapy are also summarized. SUMMARY: With increased knowledge of the pathologic mechanisms and interacting proteins associated with merlin, the research community is poised to begin trials of targeted interventions in vitro and in the current mouse models.