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Objective Eye tracking technology has been employed in assessing ocular motor and vestibular function following vestibular and neurologic conditions, including traumatic brain injury (TBI). Assessments include tests that provide visual and motion (rotation) stimuli while recording horizontal, vertical, and torsional eye movements. While some of these tests have shown diagnostic promise in previous studies, their use in clinical practice is limited by the lack of normative data. The goal of this study was to construct normative reference ranges to be used when comparing patients' results. Methods Optokinetic response, subjective visual horizontal and vertical, and rotation tests were administered to male and female volunteers, ages 18‐45, who were free from neurological, vestibular disorders, or other head injuries. Tests were administered using either a rotatory chair or a portable virtual reality‐like goggle equipped with video‐oculography. Results Reference values for eye movements in response to different patterns of stimuli were analyzed from 290 to 449 participants. Analysis of gender (self‐reported) or age when grouped as pediatric (late adolescent; 18‐21 years of age) and adult (21‐45 years of age) revealed no effects on the test metrics. Data were pooled and presented for each test metric as the 95% reference interval (RI) with 90% confidence intervals (CI) on upper and lower limits of the RI. Conclusions This normative database can serve as a tool to aid in diagnosis, treatment, and/or rehabilitation protocols for vestibular and neurological conditions, including mild TBI (mTBI). This database has been cleared by the FDA for use in clinical practice (K192186). Level of evidence 2b

The PhenX Toolkit (https://www.phenxtoolkit.org/) is an online catalog of recommended measurement protocols to facilitate cross-study analyses for biomedical research. An expert review panel (ERP) reviewed and updated the PhenX Toolkit Speech and Hearing domain to improve the precision and consistency of speech, language, and hearing disorder phenotypes. A three-member ERP convened in August 2018 to review the measurement protocols in the PhenX Speech and Hearing domain. Aided by three additional experts in voice assessment, vertigo, and stuttering, the ERP updated the 28 protocols to reflect the latest science and technology. ERP recommendations include six new protocols, five updated protocols (from the same source), and one retired protocol. New additions include two voice-related, three hearing-related, and two speech-related protocols. Additions reflect new phone/tablet applications for hearing and language, and clinical evaluations of voice. "Language" was added to the domain name, which is now "Speech, Language, and Hearing," to represent language-related protocols. These protocols can facilitate the assessment of speech, language, and hearing in clinical and population research. Common data elements (i.e., use of the same variables across studies) used by geneticists, otolaryngologists, audiologists, speech-language pathologists, and in other disciplines can lead to cross-study data integration and increased statistical power when studies are combined.

Background The Oesophago-Gastric Anastomosis Audit (OGAA) is an international collaborative group set up to study anastomotic leak outcomes after oesophagectomy for cancer. This Delphi study aimed to prioritize future research areas of unmet clinical need in RCTs to reduce anastomotic leaks. Methods A modified Delphi process was overseen by the OGAA committee, national leads, and engaged clinicians from high-income countries (HICs) and low/middle-income countries (LMICs). A three-stage iterative process was used to prioritize research topics, including a scoping systematic review (stage 1), and two rounds of anonymous electronic voting (stages 2 and 3) addressing research priority and ability to recruit. Stratified analyses were performed by country income. Results In stage 1, the steering committee proposed research topics across six domains: preoperative optimization, surgical oncology, technical approach, anastomotic technique, enhanced recovery and nutrition, and management of leaks. In stages 2 and stage 3, 192 and 171 respondents respectively participated in online voting. Prioritized research topics include prehabilitation, anastomotic technique, and timing of surgery after neoadjuvant chemo(radio)therapy. Stratified analyses by country income demonstrated no significant differences in research priorities between HICs and LMICs. However, for ability to recruit, there were significant differences between LMICs and HICs for themes related to the technical approach (minimally invasive, width of gastric tube, ischaemic preconditioning) and location of the anastomosis. Conclusion Several areas of research priority are consistent across LMICs and HICs, but discrepancies in ability to recruit by country income will inform future study design.

Introduction Skin and soft-tissue infections (SSTIs) are an important cause of infectious disease morbidity among military populations. Due to the high direct and indirect costs associated with SSTIs, particularly with methicillin-resistant Staphylococcus aureus (MRSA) infections, there remains a critical need for the development and evaluation of SSTI prevention strategies among high-risk military personnel. Herein, we review efforts of the Infectious Disease Clinical Research Program (IDCRP) related to the prevention of SSTIs in the military. Methods The IDCRP of the Uniformed Services University has conducted clinical research protocols on SSTI epidemiology and prevention among military personnel since 2009. Observational studies have examined the epidemiology of Staphylococcus aureus colonization and SSTI in training and deployment settings. Two randomized controlled trials of personal hygiene strategies for SSTI prevention at Marine Corps Base Quantico (Virginia) and Fort Benning (Georgia) were performed. Lastly, two vaccine trials have been conducted by the IDCRP, including a Phase 2 S. aureus vaccine trial (currently ongoing) among military trainees. Results Military recruits and deployed personnel experience an intense and prolonged exposure to S. aureus, the major causative agent of SSTI. The burden of S. aureus colonization and SSTI is particularly high in military trainees. Hygiene-based trials for S. aureus decolonization among military trainees were not effective in reducing rates of SSTI. In January 2018, the IDCRP initiated a Phase 2 S. aureus vaccine trial among the US Army Infantry training population at Fort Benning. Conclusions In the military, a disproportionate burden of SSTIs is borne by the recruit population. Strategies relying upon routine application of agents for S. aureus decolonization have not been effective in preventing SSTIs. A novel S. aureus vaccine candidate is being currently evaluated in a military training population and may represent a new opportunity to prevent SSTIs for the military.

A recent workshop titled “Developing Models to Study Polymicrobial Infections,” sponsored by the Dartmouth Cystic Fibrosis Center (DartCF), explored the development of new models to study the polymicrobial infections associated with the airways of persons with cystic fibrosis (CF). The workshop gathered 35+ investigators over two virtual sessions. Here, we present the findings of this workshop, summarize some of the challenges involved with developing such models, and suggest three frameworks to tackle this complex problem. The frameworks proposed here, we believe, could be generally useful in developing new model systems for other infectious diseases. Developing and validating new approaches to study the complex polymicrobial communities in the CF airway could open windows to new therapeutics to treat these recalcitrant infections, as well as uncovering organizing principles applicable to chronic polymicrobial infections more generally.

Objective: the aim of this study was to investigate the association of obesity with in-hospital coronavirus disease 2019 (COVID-19) outcomes in different ethnic groups.Methods: patients admitted to hospital with COVID-19 in the United Kingdom through the Clinical Characterisation Protocol UK (CCP-UK) developed by the International Severe Acute Respiratory and emerging Infections Consortium (ISARIC) were included from February 6 to October 12, 2020. Ethnicity was classified as White, South Asian, Black, and other minority ethnic groups. Outcomes were admission to critical care, mechanical ventilation, and in-hospital mortality, adjusted for age, sex, and chronic diseases.Results: of the participants included, 54,254 (age = 76 years; 45.0% women) were White, 3,728 (57 years; 41.1% women) were South Asian, 2,523 (58 years; 44.9% women) were Black, and 5,427 (61 years; 40.8% women) were other ethnicities. Obesity was associated with all outcomes in all ethnic groups, with associations strongest for black ethnicities. When stratified by ethnicity and obesity status, the odds ratios for admission to critical care, mechanical ventilation, and mortality in black ethnicities with obesity were 3.91 (3.13-4.88), 5.03 (3.94-6.63), and 1.93 (1.49-2.51), respectively, compared with White ethnicities without obesity.Conclusions: obesity was associated with an elevated risk of in-hospital COVID-19 outcomes in all ethnic groups, with associations strongest in Black ethnicities.

Background The vestibular system is a multifaceted, integrative sensory system that is often referred to as the "multi-sensory" sense. There is an extensive literature about the vestibular sensory organs and afferent nerve pathways; however, this rich resource is often unknown to the headache specialist. Aims In this review, we highlight the significance of vestibular sensory processing beyond its role in the maintenance of balance. The role of the vestibular system in migraine pathophysiology is emphasized, not just in how it impacts dizziness or nausea, but also in its higher order effects on mood and cognition. How the vestibular system responds to current and new migraine therapies, such as anti-CGRP (calcitonin gene-related peptide) antibodies, is also discussed. Conclusions The vestibular system is not just about balance; this should be taken into account by clinicians as they assess their patients' associated non-headache symptoms. There is a co-occurrence of migraine and vestibular-based problems and a confluence of disciplines relevant to vestibular migraine.

It is acknowledged that ancestry may play a role in the likelihood of reporting motion sickness, based upon questionnaires in which symptoms are reported more frequently in individuals with Asian ancestry. This study compares motion sickness and related vertigo syndromes in Thai and Thai-Chinese populations. The Motion Sickness Questionnaire; Albany Panic and Phobia Questionnaire; Acrophobia Questionnaire; Body Symptoms Questionnaire and the Situational Characteristics Questionnaire were administered to 128 participants. Eighty-eight participants had a father, mother and all grandparents of Thai origin, while 44 participants had with at least one Chinese ancestor among parents or grandparents. All responses were similar between groups except regarding fear of heights, which is significantly higher in Thai participants without recent Chinese ancestors. Reported motion sickness sensitivity is similar between Thai and Chinese populations. The group differences for some fear of heights items may be linked to each group’ previous experience with heights. Results also suggest that although conquering a fear of heights might require specific visuo-vestibular adaptations, these adaptations alone may not be sufficient to lessen an individual’sfear of heights.

Background In the Autumn of 2016, diplomatic personnel residing in Havana began to present with symptoms of dizziness, ear pain, and tinnitus that emerged after perception of high frequency noise and/or a pressure sensation. Understanding the acute symptoms of this disorder is important for better defining the disorder and developing optimal diagnostic, preventive, and treatment algorithms. Objectives To define the presenting symptoms in a cohort of patients in the acute time period after perceiving a noise/pressure exposure in Havana. Design/settings/participants Review of 25 symptomatic individuals who reported a localized sensation of noise/pressure and 10 asymptomatic individuals (roommates of those affected) who did not experience the sound/pressure. Results Immediately after the exposure, the majority of individuals reported intense ear pain in one or both ears and experienced tinnitus. All of the individuals noticed unsteadiness and features of cognitive impairment. On presentation to our center, dizziness (92%) and cognitive complaints (56%) were the most common symptoms. Formal testing revealed that 100% of individuals had an otolithic abnormality and evidence of cognitive dysfunction. Conclusion and relevance This study focuses on the acute presentation of a phenomenon in which symptoms emerge after perception of a localized noise/pressure and in which the acute symptomology includes the universal nature of vestibular injuries and select cognitive deficits. The findings presented in this acute group of patients begin to provide a better picture of the initial injury pattern seen after this exposure and may allow for more accurate diagnosis of this disorder in future cases. Level of evidence Retrospective review.

It is well-known that airborne sound induces vibration of the eardrum, the coupled middle ear bones, and the inner ear. Sound transmission to the inner ear is attenuated by damage or dysfunction in the eardrum or ossicular chain. Corrective devices often use contact shakers to directly vibrate the temporal bone of the skull, delivering sound. We investigate an alternative, noncontact method of sound transmission that uses ultrasonic signals to transmit sound into the auditory and vestibular systems. Minimal literature exists describing ultrasonic hearing, largely due to attenuation of air-conducted frequencies above 20 kHz. High-amplitude airborne sound incident upon the skull can induce temporal bone system vibrations along an unconventional structural path. Finite-element-based acoustic modeling of the auditory and vestibular anatomy reveals resonant behavior in structural components of the middle and inner ear at ultrasonic frequencies. These “built-in sound amplifiers” can be leveraged to compensate for impedance mismatches experienced in airborne ultrasound transmission. By heterodyning (amplitude modulating) a targeted ultrasonic carrier signal with an audio signal, the nonlinearities of acoustic propagation and the auditory and vestibular sense organs allow interpretation of heterodyne signals. These techniques provide a foundation to improve a wide variety of communication equipment, including hearing aids, without interfering with balance sensations.

Purpose: To evaluate differences in the characteristics and outcomes of intensive care unit (ICU) patients over time. Methods: We reviewed all epidemiological data, including comorbidities, types and severity of organ failure, interventions, lengths of stay and outcome, for patients from the Sepsis Occurrence in Acutely ill Patients (SOAP) study, an observational study conducted in European intensive care units in 2002, and the Intensive Care Over Nations (ICON) audit, a survey of intensive care unit patients conducted in 2012. Results: We compared the 3147 patients from the SOAP study with the 4852 patients from the ICON audit admitted to intensive care units in the same countries as those in the SOAP study. The ICON patients were older (62.5 ± 17.0 vs. 60.6 ± 17.4 years) and had higher severity scores than the SOAP patients. The proportion of patients with sepsis at any time during the intensive care unit stay was slightly higher in the ICON study (31.9 vs. 29.6%, p = 0.03). In multilevel analysis, the adjusted odds of ICU mortality were significantly lower for ICON patients than for SOAP patients, particularly in patients with sepsis [OR 0.45 (0.35–0.59), p < 0.001]. Conclusions: Over the 10-year period between 2002 and 2012, the proportion of patients with sepsis admitted to European ICUs remained relatively stable, but the severity of disease increased. In multilevel analysis, the odds of ICU mortality were lower in our 2012 cohort compared to our 2002 cohort, particularly in patients with sepsis., 0, info:eu-repo/semantics/published

In late 2016, diplomats in Havana, Cuba, began presenting with a unique symptom complex after perceiving a strange noise and/or feeling a pressure field in their domicile. This report is a retrospective, quantitative analysis of video-oculography data of pupillary light reflex performance and binocular disparity-driven eye and pupil movements during the acute time period after the reported exposure. The patterns of response in these 19 individuals are markedly different than those seen in a group of individuals with the usual acute mild traumatic brain injury (17 subjects) and from 62 control subjects (21–60 years old) with no injury. Non-linear least squares regression was used to estimate the model parameters from the eye movement and the pupil measurements (1). Linear discriminant analysis was then used to identify a classifier for an objective discrimination of the groups with >91% accuracy and no confusion between the acute neurosensory findings among the members of the Havana diplomatic community and the subjects with acute mild traumatic brain injury. This pattern difference in eye and pupil behavior may be a useful screen to help objectively distinguish blunt trauma from Havana-type effects in the future and to guide the affected individuals to appropriate care.

Objective: This communication is the first assessment of outcomes after surgical repair of cochlea-facial nerve dehiscence (CFD) in a series of patients. Pre- and post-operative quantitative measurement of validated survey instruments, symptoms, diagnostic findings and anonymous video descriptions of symptoms in a cohort of 16 patients with CFD and third window syndrome (TWS) symptoms were systematically studied. Study design: Observational analytic case-control study. Setting: Quaternary referral center. Patients: Group 1 had 8 patients (5 children and 3 adults) with CFD and TWS who underwent surgical management using a previously described round window reinforcement technique. Group 2 had 8 patients (2 children and 6 adults) with CFD who did not have surgical intervention. Interventions: The Dizziness Handicap Inventory (DHI) and Headache Impact Test (HIT-6) were administered pre-operatively and post-operatively. In addition, diagnostic findings of comprehensive audiometry, cervical vestibular evoked myogenic potential (cVEMP) thresholds and electrocochleography (ECoG) were studied. Symptoms before and after surgical intervention were compared. Main outcome measures: Pre- vs. post-operative DHI, HIT-6, and audiometric data were compared statistically. The thresholds and amplitudes for cVEMP in symptomatic ears, ears with cochlea-facial nerve dehiscence and ears without CFD were compared statistically. Results: There was a highly significant improvement in DHI and HIT-6 at pre- vs. post-operative (p < 0.0001 and p < 0.001, respectively). The age range was 12.8–52.9 years at the time of surgery (mean = 24.7 years). There were 6 females and 2 males. All 8 had a history of trauma before the onset of their symptoms. The mean cVEMP threshold was 75 dB nHL (SD 3.8) for the operated ear and 85.7 dB (SD 10.6) for the unoperated ear. In contrast to superior semicircular canal dehiscence, where most ears have abnormal ECoG findings suggestive of endolymphatic hydrops, only 1 of 8 operated CFD ears (1 of 16 ears) had an abnormal ECoG study. Conclusions: Overall there was a marked improvement in DHI, HIT-6 and symptoms post-operatively. Statistically significant reduction in cVEMP thresholds was observed in patients with radiographic evidence of CFD. Surgical management with round window reinforcement in patients with CFD was associated with improved symptoms and outcomes measures.

Eye movements measured by high precision eye-tracking technology represent a sensitive, objective, and non-invasive method to probe functional neural pathways. Oculomotor tests (e.g., saccades and smooth pursuit), tests that involve cognitive processing (e.g., antisaccade and predictive saccade), and reaction time tests have increasingly been showing utility in the diagnosis and monitoring of mild traumatic brain injury (mTBI) in research settings. Currently, the adoption of these tests into clinical practice is hampered by a lack of a normative data set. The goal of this study was to construct a normative database to be used as a reference for comparing patients’ results. Oculomotor, cognitive, and reaction time tests were administered to male and female volunteers, aged 18–45, who were free of any neurological, vestibular disorders, or other head injuries. Tests were delivered using either a rotatory chair equipped with video-oculography goggles (VOG) or a portable virtual reality-like VOG goggle device with incorporated infrared eye-tracking technology. Statistical analysis revealed no effects of age on test metrics when participant data were divided into pediatric (i.e.,18–21 years, following FDA criteria) and adult (i.e., 21–45 years) groups. Gender (self-reported) had an effect on auditory reaction time, with males being faster than females. Pooled data were used to construct a normative database using 95% reference intervals (RI) with 90% confidence intervals on the upper and lower limits of the RI. The availability of these RIs readily allows clinicians to identify specific metrics that are deficient, therefore aiding in rapid triage, informing and monitoring treatment and/or rehabilitation protocols, and aiding in the return to duty/activity decision. This database is FDA cleared for use in clinical practice (K192186).

This essay explores the process of the acquisition and application of knowledge by the Department of Defense (DoD) of the United States of America, based upon policies and practices of the Office of Naval Research (ONR). The ONR's “Systems-of-Systems” approach organizes the academic, private, and military sectors to meet critical operational needs over a twenty-year horizon. We describe the frameworks for organizing the interplay of different sectors and stakeholders in knowledge acquisition, knowledge application, and the production of operational deliverables for projected needs. It is often not appreciated that the ONR prioritizes development of innovative fundamental research, which is often interdisciplinary. Nearly sixty Nobel Laureates have contributed to these endeavors, including thirty-seven laureates since 1980. ONR-supported fundamental research has been a sustainable process for fostering scientific advances and selective production of state-of-the-art deliverables that support military operational needs, often with collateral significant benefits to the civilian sector.

Background Military trainees are at increased risk for methicillin-resistant Staphylococcus aureus (MRSA) skin and soft tissue infection (SSTI). Whole genome sequencing (WGS) can refine our understanding of MRSA transmission and microevolution in congregate settings. Methods We conducted a prospective case-control study of SSTI among US Army infantry trainees at Fort Benning, Georgia, from July 2012 to December 2014. We identified clusters of USA300 MRSA SSTI within select training classes and performed WGS on clinical isolates. We then linked genomic, phylogenetic, epidemiologic, and clinical data in order to evaluate intra- and interclass disease transmission. Furthermore, among cases of recurrent MRSA SSTI, we evaluated the intrahost relatedness of infecting strains. Results Nine training classes with ≥5 cases of USA300 MRSA SSTI were selected. Eighty USA300 MRSA clinical isolates from 74 trainees, 6 (8.1%) of whom had recurrent infection, were subjected to WGS. We identified 2719 single nucleotide variants (SNVs). The overall median (range) SNV difference between isolates was 173 (1-339). Intraclass median SNV differences ranged from 23 to 245. Two phylogenetic clusters were suggestive of interclass MRSA transmission. One of these clusters stemmed from 2 classes that were separated by a 13-month period but housed in the same barracks. Among trainees with recurrent MRSA SSTI, the intrahost median SNV difference was 7.5 (1-48). Conclusions Application of WGS revealed intra- and interclass transmission of MRSA among military trainees. An interclass cluster between 2 noncontemporaneous classes suggests a long-term reservoir for MRSA in this setting.

OBJECTIVES The objective of this work is to examine the outcomes of a set of objective measures for evaluating individuals with minor traumatic brain injury (mTBI) over the sub-acute time period. These methods involve tests of oculomotor, vestibular, and reaction time functions. This work expands upon published work examining these test results at the time of presentation. STUDY DESIGN This study is a prospective age- and sex-matched controlled study. MATERIALS AND METHODS The subject group was composed of 106 individuals with mTBI and 300 age- and sex-matched controls without a history of mTBI. All individuals agreeing to participate in the study underwent a battery of oculomotor, vestibular, and reaction time tests (OVRT). Those subjects with mTBI underwent these tests at presentation (within 6 days of injury) and 1 and 2weeks post injury. These outcomes were compared to each other over time as well as to results from the controls that underwent 1 test session. RESULTS Six measures from 5 tests can classify the control and mTBI during Session 1 with a true positive rate (sensitivity) of 84.9% and true negative rate (specificity) of 97.0%. Patterns of abnormalities changed over time in the mTBI group and overall normalized in a subset of individuals at the third (final) testing session. CONCLUSIONS We describe an objective and effective second generation testing algorithm for diagnosing and following the prognosis of mTBI/concussion. This testing paradigm will allow investigators to institute better treatments and provide more accurate return to activity advice. LEVEL OF EVIDENCE 3.

The connotation of “nausea” has changed across several millennia. The medical term ‘nausea’ is derived from the classical Greek terms ναυτια and ναυσια, which designated the signs and symptoms of seasickness. In classical texts, nausea referred to a wide range of perceptions and actions, including lethargy and disengagement, headache (migraine), and anorexia, with an awareness that vomiting was imminent only when the condition was severe. However, some recent articles have limited the definition to the sensations that immediately precede emesis. Defining nausea is complicated by the fact that it has many triggers, and can build-up slowly or rapidly, such that the prodromal signs and symptoms can vary. In particular, disengagement responses referred to as the “sopite syndrome” are typically present only when emetic stimuli are moderately provocative, and do not quickly culminate in vomiting or disengagement from the triggering event. This review considers how the definition of “nausea” has evolved over time, and summarizes the physiological changes that occur prior to vomiting that may be indicative of nausea. Also described are differences in the perception of nausea, as well as the accompanying physiological responses, that occur with varying stimuli. This information is synthesized to provide an operational definition of nausea.

Little research exists describing how the human auditory and vestibular systems respond to higher intensity pressure at ultrasonic frequencies. In large part, this literature gap arises from the well-known attenuation of frequencies higher than 20 kHz by the air-conduction hearing path. Most studies of bone-conducted sound also avoid characterization of ultrasonic sound transmission, in part because the basilar membrane of the cochlea is seen as a physical Fourier analyzer which does not have sensitivity above 20 kHz. We used finite-element modeling of human and macaque intracranial structures to investigate transmission of modulated airborne ultrasound signals in the skull base, middle ear, and inner ear. Even in the presence of soft tissue damping, a family of resonant structural features could locally amplify sound within ultrasonic frequency range. High-amplitude, air-propagated ultrasound carrier signals, heterodyned with audio-band signals, may be able to use these resonant features to deliver perceptible signals to the cochlea without activation of the vestibular sensors. These principles offer the potential to develop new, less obtrusive, noncontact equipment enabling personal communication. [Work supported by ONR Grant N00014-18-1-2157.]

Applications seeking to exploit electromagnetic scattering characteristics of an imaging or detection problem typically require a large number of electromagnetic simulations in order to understand relevant object phenomena. It has been shown in a previous work that deep learning may be used to increase the efficiency of creating such datasets by providing estimations comparable to simulation results. In this work, we further investigate the utility of deep learning for electromagnetic simulation prediction by adding to the existing training and testing dataset while also incorporating additional material properties. Specifically, we explore using artificial neural networks to learn the connection between a generic object and its resulting bistatic radar cross section, thereby removing the need to repeatedly perform timely simulations. While deep learning can be seen as a computationally expensive technique, this cost is only experienced during the training of the system and not subsequently in the acquisition of results. The goal of this work is to further investigate the applicability of deep learning for electromagnetic simulation prediction as well as its potential limitations. Additionally, performance is compared for different data pre-processing techniques focused on data reduction.

Mild traumatic brain injury (mTBI) is a disorder that has gained increasing attention in the last several years because of its impact on professional sports and U.S. Servicemembers returning after deployment overseas. In fact, mTBI occurs in all segments of the population and has a significant impact on individuals over a wide range of ages who are injured in a variety of settings. In simplest terms, mTBI is just as the words describe, a brain injury that is mild and caused by trauma. It is essentially synonymous with a concussion. However, in modern usage the term mTBI has taken on more significance and has come to signify not only the injury but all of the associated signs and symptoms, whether physical, emotional, or psychosocial. Much of this new notoriety stems from the fact that the nosology of mTBI is ill defined and, despite a significant amount of study, mechanistic aspects of the disorder are poorly understood. The goal of this chapter is not so much to provide a precise definition but rather to explore how definitions affect the translational scientific approach to advancing diagnosis and care. The chapter appears first to set the tone for this entire volume. In practice the clinician looks at a patient who, after suffering a head injury, and appears “not quite right” (NQR). We ask researchers to figure out how to best diagnose and optimally treat this very heterogenous condition. We hope that this volume helps to focus the field on the task of better defining and treating patients who are NQR after a documented mild traumatic event.

The diagnosis of mild traumatic brain injury (mTBI) or concussion relies on a documented event (e.g., blunt trauma, rapid acceleration/deceleration of the head, or blast wave exposure) and the presence of clinical signs or symptoms. Because the injury is mild, signs may be very subtle and much reliance is placed on symptom reports. Symptoms are subjective descriptions that are assessed with specific vocabulary in standard questionnaires. This communication describes the potential of existing Narrative Theory, based on recent story science research, to explain major portions of the gender discrepancies found in rates, patterns, and vocabulary used by patients to report mTBI symptoms. We present the applicable elements of current story science findings and demonstrate their potential benefit for improving the interpretation of reported mTBI symptoms.

This chapter reviews the search for objective metrics for diagnosing mild traumatic brain injury. Tests have been proposed that measure sensory, motor, autonomic and neurocognitive functions, as well as molecular biomarkers. The challenges to interpret the test results in terms of mechanisms of injury and recovery are discussed, as well as progress toward the pragmatic goals of explaining symptom complexes, identifying injury and tracking recovery is also discussed.

ObjectiveCan oculomotor, vestibular, reaction time and cognitive eye-tracking tests (OVRT-C) assess mild traumatic brain injury?BackgroundOVRT-C tests using eye tracking technology have been employed in our previous studies for assessing mild traumatic brain injury (mTBI). Here we present a composite Concussion Assessment algorithm that incorporates these findings.Design/MethodsConcussion Assessment algorithm was based on a data analysis from 406 males and females 18–45 years old. The subjects included 106 patients diagnosed with mTBI and 300 healthy controls. Diagnosis of mTBI was made using accepted medical practice. The participants were tested with a battery of OVRT-C tests delivered on the I-Portal Neuro Otologic Test Center (Dx NOTC) device (Neurolign Technology). A logistic regression model was used to derive the algorithm using a random sample of 70% of the data-set and validated on the remaining 30% of the data-set. Device test-retest reliability and inter-rater variability were assessed in a separate study in healthy control volunteers, ages 19–43 (n = 30). Subjects were tested with OVRT-C tests using the Dx100 which is equivalent to the NOTC. Test-retest reliability was assessed using Intraclass Correlation Coefficient (ICC) and Cronbach's alpha; testers and devices influence were assessed using a random effect regression model.ResultsTest-retest reliability of OVRT-C tests using eye tracking technology was acceptable (ICC >0.6 for all variables). The Concussion assessment algorithm was based on six OVRT-C tests. In the validation data Concussion Assessment algorithm was able to separate concussed versus controls with a sensitivity of 78.6% and specificity of 72.3%.ConclusionsOVRT-C tests delivered on I-Portal devices are repeatable and reliable. The assessment can identify mTBI subjects within an acute time post-injury with high sensitivity and specificity. The results support the use of this eye tracking device as well as the assessment to aid in the diagnosis of mTBI for patients 18–45 year old.

Background Mild traumatic brain injury (TBI) is a common public health issue that may contribute to chronic degenerative disorders. Membrane lipids play a key role in tissue responses to injury, both as cell signals and as components of membrane structure and cell signaling. This study demonstrates the ability of high resolution mass spectrometry imaging (MSI) to assess sequences of responses of lipid species in a rat controlled cortical impact model for concussion. New method A matrix of implanted silver nanoparticles was implanted superficially in brain sections for matrix-assisted laser desorption (MALDI) imaging of 50 μm diameter microdomains across unfixed cryostat sections of rat brain. Ion-mobility time-of-flight MS was used to analyze and map changes over time in brain lipid composition in a rats after Controlled Cortical Impact (CCI) TBI. Results Brain MS images showed changes in sphingolipids near the CCI site, including increased ceramides and decreased sphingomyelins, accompanied by changes in glycerophospholipids and cholesterol derivatives. The kinetics differed for each lipid class; for example ceramides increased as early as 1 day after the injury whereas other lipids changes occurred between 3 and 7 days post injury. Comparison with existing method(s) Silver nanoparticles MALDI matrix is a sensitive new tool for revealing previously undetectable cellular injury response and remodeling in neural, glial and vascular structure of the brain. Conclusions Lipid biochemical and structural changes after TBI could help highlighting molecules that can be used to determine the severity of such injuries as well as to evaluate the efficacy of potential treatments.

Background Traumatic brain injury is an increasingly prevalent injury seen in both civilian and military populations. Regardless of the mechanisms of injury, the most common sub-type of injury continues to be mild traumatic brain injury. Within the last decade, there has been tremendous growth in the literature regarding this disease entity. Purpose To describe the obstacles necessary to overcome in performing a rigorous and sound clinical research study investigating mild traumatic brain injury. This examination begins by a consideration of changing standards for good faith open and total reporting of any and all conflicts of interest or commitment. This issue is particularly critical in mTBI research. We next examine obstacles that include but are not limited to diagnostic criteria, inclusion/exclusion criteria, source of injury, previous history of injury, presence of comorbid conditions and proper informed consent of participants. Frequently, multi-center studies are necessary for adequate subject accrual with the added challenges of site coordination, data core management and site specific study conduct. We propose a total reversal to the traditional translational research approach where clinical studies drive new concepts for future basic science studies. Conclusions There have been few mild traumatic brain injury clinical trials in the literature with treatments/interventions that have been able to overcome many of these described obstacles. We look forward to the results of current and ongoing clinical mild traumatic brain injury studies providing the tools necessary for the next generation of basic science projects.

Objective: Patients with peripheral vestibular dysfunction because of gravitational receptor asymmetries display signs of cognitive dysfunction and are assumed to have neurobehavioral sequelae. This was tested with pre- and postoperatively quantitative measurements in three cohort groups with superior semicircular canal dehiscence syndrome (SSCDS) symptoms with: 1) superior canal dehiscence (SCD) repaired via a middle cranial fossa craniotomy and canal plugging only; 2) otic capsule defects not visualized with imaging (no-iOCD) repaired with round window reinforcement (RWR) only; or 3) both SCD plugging and subsequent development of no-iOCD followed by RWR. Study Design: Prospective patient series. Setting: Tertiary referral center. Patients: There were 13 adult and 4 pediatric patients with SSCDS who had completion of neuropsychology test batteries pre- and every 3 months postoperatively. Eight patients had no-iOCD and RWR exclusively, 5 had SCD and plugging exclusively, and 4 had both SCD plugging and then development of no-iOCD with RWR. These cohorts included SSCDS with 2 different dehiscence locations. Interventions: Completion of a neuropsychology test battery preoperatively and at 3, 6, 9, and 12 months postoperatively that included: Beck Depression Inventory-II (BDI); Wide Range Intelligence Test (WRIT FSIQ) including average verbal (crystallized intelligence) and visual (fluid intelligence); Wide Range Assessment of Memory and Learning (WRAML), including the four domains of verbal memory, visual memory, attention/concentration, and working memory; and Delis–Kaplan Executive Function System (D-KEFS). The Dizziness Handicap Inventory (DHI) and the Headache Impact Test (HIT-6) were also completed to assess the impact of their disease on activities pre- and postoperatively. Main Outcome Measures: Quantitative and statistical analysis of their cognitive and neurobehavioral function. Results: The pattern of differences between the SCD group and the no-iOCD group from WRAML verbal, visual, and attention test performance indicate different postoperative clinical trajectories. For the WRAML, there was a statistically significant improvement for visual memory and verbal memory for the no-iOCD only and both (SCD and subsequent no-iOCD) groups, but no mean improvement for the SCD only group. By contrast, the no-iOCD group had significantly lower scores on the WRAML attention test preoperatively, but they recovered postoperatively to match the other groups. The preoperative findings and postoperative outcomes did not differ significantly among patient groups on the WRAML working memory test, D-KEFS motor scores, D-KEFS number and letter scores, or Wide Range Intelligence Test scores. There was a significant decrease in the BDI for all groups. The IQ scores were unchanged. There was a statistically significant improvement in the DHI and HIT-6 scores postoperatively in all groups. Conclusions: There was a marked overall improvement in cognitive and neurobehavioral function postoperatively. Variability may result from duration of underlying disease before intervention. The initial decrement or delay in performance improvement measured in several patients may represent brain reorganization. Greater longitudinal data and greater subject numbers are necessary to better understand and optimize cognitive recovery.

Applications seeking to exploit electromagnetic scattering characteristics of an imaging or detection problem typically require a large number of electromagnetic simulations. Because these simulations are often computationally intensive, valuable resources are required to perform the simulations in an efficient and timely manner, which is not always freely available or accessible. In this work, we investigate the utility of deep learning for electromagnetic simulation prediction. Specifically, we explore using artificial neural networks to learn the connection between a generic object and its resulting bistatic radar cross section, thereby removing the need to repeatedly perform timely simulations. Such a system would be trained in an offline setting and consequently enable rapid bistatic radar cross section predictions for new objects in the future. While deep learning can be seen as a computationally expensive technique, this cost is only experienced during the training of the system and not subsequently in the acquisition of results. The goal of this work is to learn the applicability of deep learning for electromagnetic simulation prediction as well as its potential limitations. Several simple objects are investigated and a thorough statistical analysis will be used to assess the performance of our proposed method.

Synthetic aperture radar (SAR) benefits from persistent imaging capabilities that are not reliant on factors such as weather or time of day. One area that may benefit from readily available imaging capabilities is road damage detection and assessment occurring from disasters such as earthquakes, sinkholes, or mudslides. This work investigates the performance of a pre-screener for an automatic detection system used to identify locations and quantify the severity of road damage present in SAR imagery. The proposed pre-screener is comprised of two components: advanced image processing and classification. Image processing is used to condition the data, removing non-pertinent information from the imagery which helps the classifier achieve better performance. Specifically, we utilize shearlets; these are powerful filters that capture anisotropic features with good localization and high directional sensitivity. Classification is achieved through the use of a convolutional neural network, and performance is reported as classification accuracy. Experiments are conducted on satellite SAR imagery. Specifically, we investigate Sentinel-1 imagery containing both damaged and non-damaged roads.

Background Several high-profile violent incidents have occurred within emergency departments (EDs). There are no recent studies reporting the effectiveness of ED metal detection. Objective Our aim was to assess the effect of metal detection on ED weapons retrieval. Methods In September 2011, a metal detector was installed at the entrance of an urban, high-volume teaching hospital ED. The security company recorded retrieved firearms, knives, chemical sprays, and other weapons. We performed qualitative analysis of weapons retrieval data for a 26-month period. Results A total of 5877 weapons were retrieved, an average of 218 per month: 268 firearms, 4842 knives, 512 chemical sprays, and 275 other weapons, such as brass knuckles, stun guns, and box cutters. The number of retrieved guns decreased from 2012 to 2013 (from 182 to 47), despite an increase in metal detection hours from 8 h per day to 16 h per day. The number of retrieved knives, chemical sprays, and other weapons increased. Recovered knives increased from 2062 in 2012 to 2222 in 2013, chemical sprays increased from 170 to 305, and other weapons increased from 51 to 201. Conclusions A large number of weapons were retrieved after the initiation of metal detection in the ED entrance. Increasing hours of metal detection increased the number of retrieved knives, chemical sprays, and other weapons. Retrieved firearms decreased after increasing metal detection hours. Metal detection in the ED entrance is effective in reducing entrance of weapons into the ED. Metal detectors may offer additional benefit in reducing attempts to enter with firearms.

Introduction Knowledge of disease burden attributable to functional gastrointestinal disorders (FGD) in travelers is lacking, despite the high incidence of travelers' diarrhea (TD) associated with increased FGD risk. One tool for assessing the impact of disease on health-related quality of life is the health utility index (HUI), which values health states based on preferential health outcomes. Health utilities can be used as preference weights in the estimation of quality-adjusted life-years (QALYs). Methods Six months following travel to Egypt or Turkey, 120 US military personnel completed a survey on TD during deployment, health-related quality of life (SF-36), and the onset of functional bowel disorders (Rome II). Elements from the SF-36 were used to develop SF-6D values, which were combined with health state valuations to enable calculation of HUI scores for each subject. Mean index scores were compared across functional outcomes, specific symptoms, and demographic profiles. Results The presence of FGD significantly reduced index scores, with irritable bowel syndrome (IBS) and dyspepsia showing the greatest impact (−0.17 and −0.19, respectively) compared with those with no FGD (p < 0.05). Importantly, however, several individuals met multiple FGD outcome definitions. Additionally, a number of symptoms associated with abnormal bowel habits and abdominal pain were associated with reduced index scores regardless of outcome. Conclusion FGD are associated with significant morbidity as assessed by HUIs. Given the strong link between TD and FGD as well as the large number of travelers from the developed to the developing world, additional study is needed to further understand this association and efforts aimed at primary disease prevention are warranted.

One promising technique for improving tunnel detection is the use of spotlight synthetic aperture radar (SL-SAR) in conjunction with focusing techniques. Still, clutter arises from surface variations while severe attenuation of the target signal occurs due to the dielectric properties of the soil. To combat these ill-effects, this work aims to improve imaging and detection of underground tunnels by examining the feasibility of matched illumination waveform design for tunnel detection applications. The tunnel impulse response is incorporated in an optimum waveform derivation scheme which aims to maximize the signal-to-interference and noise ratio (SINR) at the receiver output. Numerical electromagnetic simulations are used to consider wave propagation in realistic soil scenarios which include uniform and non-uniform moisture profiles. It is demonstrated that by considering matched illumination waveforms for transmission in SL-SAR systems, an improvement in the detection and imaging capabilities is achieved through enhanced SINR.

Chlorhexidine has been increasingly utilized in outpatient settings to control methicillin-resistant Staphylococcus aureus (MRSA) outbreaks and as a component of programs for MRSA decolonization and prevention of skin and soft-tissue infections (SSTIs). The objective of this study was to determine the prevalence of chlorhexidine resistance in clinical and colonizing MRSA isolates obtained in the context of a community-based cluster-randomized controlled trial for SSTI prevention, during which 10,030 soldiers were issued chlorhexidine for body washing. We obtained epidemiological data on study participants and performed molecular analysis of MRSA isolates, including PCR assays for determinants of chlorhexidine resistance and high-level mupirocin resistance and pulsed-field gel electrophoresis (PFGE). During the study period, May 2010 to January 2012, we identified 720 MRSA isolates, of which 615 (85.4%) were available for molecular analysis, i.e., 341 clinical and 274 colonizing isolates. Overall, only 10 (1.6%) of 615 isolates were chlorhexidine resistant, including three from the chlorhexidine group and seven from nonchlorhexidine groups ( P > 0.99). Five (1.5%) of the 341 clinical isolates and five (1.8%) of the 274 colonizing isolates harbored chlorhexidine resistance genes, and four (40%) of the 10 possessed genetic determinants for mupirocin resistance. All chlorhexidine-resistant isolates were USA300. The overall prevalence of chlorhexidine resistance in MRSA isolates obtained from our study participants was low. We found no association between extended chlorhexidine use and the prevalence of chlorhexidine-resistant MRSA isolates; however, continued surveillance is warranted, as this agent continues to be utilized for infection control and prevention efforts.

BackgroundDespite the prevalence of mild traumatic brain injury (mTBI, concussion) in a wide range of occupational, sport, and military settings, accurate diagnosis and optimal treatment of concussive injuries are delayed by several challenging obstacles. Ability to measure the multisensory functional integrity of numerous neuroanatomical pathways with multiple tasks (oculomotor, vestibular and reaction time) can capture impairments of brain function.Methods106 mTBI patients and 300 control subjects were tested in the vestibular labs at 2 military hospitals. Patients were tested 3 times at average 2.5, 8.5 and 15.8 days post-injury. All patients completed a health history questionnaire, a dizziness handicap index (DHI), a functional gait index (FGI), and Trail Making Tests (TMTs) and were assessed by a battery of tests with video-oculography (I-Portal VOG) comprised of a head mounted, high speed eye tracking system on a rotary chair device (I-Portal Neuro-Otologic Test Center). The individuals in the study performed multiple tests including saccades, antisaccade, pursuit tracking, nystagmus, optokinetic, vestibular motion, and reaction time.ResultsNo single test was sufficiently predictive to have separation between controls and mTBI subjects but results from a computer controlled rotational head impulse test (crHIT), antisaccade and predictive saccade were highly correlated with mTBI for the first test session. Longitudinally, for example, 74% of patients in session 1, 56% in session 2% and 51% in session 3 had in crHIT gain or absolute asymmetry above 95% of the respective control's distribution.ConclusionThese results suggest that vestibular, oculomotor and reaction time tests using can provide an objective and reliable method of capturing and quantifying abnormal response in patients with mTBI. In addition, this type of testing can be used to monitor the recovery process.

Background Skin and soft-tissue infections (SSTI) are common among military recruits, and some experience recurrent SSTI (two infections ≥30 days apart) during training. We used whole-genome sequencing (WGS) to assess the relatedness of strains from recurrent S. aureus SSTI cases and their close contacts. Methods From 2010 to 2014, we prospectively identified SSTI cases among US Army Infantry trainees (Fort Benning, GA), obtaining infection swabs at the time of presentation for all SSTIs and multiple anatomic site colonization swabs at the time of presentation for the first infection. Thereafter, we selected cases of recurrent S. aureus SSTI with phenotypically concordant paired isolates (e.g., MRSA-MRSA). We also selected concordant colonization isolates from recurrent cases as well as concordant infection isolates from SSTI cases in the same training class as the recurrent case. Isolates were characterized by WGS. The number of single nucleotide polymorphism (SNP) differences between isolates was calculated. Phylogenetic trees were constructed to identify patterns of intra- vs. extra-host S. aureus acquisition among cases of recurrent infection. Results We identified 23 cases of recurrent S. aureus SSTI with concordant infection isolates (18 MRSA). The median (range) pairwise SNP difference for intrahost infection isolates was 15 (0–3,768); 12 (0–348), MRSA and 310 (3–3,768), MSSA. Nine (39%) were colonized with a concordant strain (5 MRSA), yielding 14 colonization isolates (7 MRSA). The median pairwise SNP difference between intrahost colonization and recurrent infection isolates was 57 (2–3,582); 5 (2–3,582), MRSA and 167 (2–313), MSSA. Infection isolates from 33 proximal cases (27 MRSA) were identified. The median pairwise SNP difference between recurrent infection isolates and that of a proximal case was 24 (1–531); 20 (1–216), MRSA and 307 (286–531), MSSA. Variant analysis showed no difference between the number of putative high impact SNPs between infection (μ = 11, σ = 20) and colonization (μ = 19, σ = 42) isolates. Conclusion WGS of S. aureus from recurrent SSTI suggests patterns of intra-host reinfection as well as intra-host acquisition/infection. Targeted decolonization may prevent recurrent S. aureus SSTI. Disclosures All authors: No reported disclosures.

Military personnel in congregate settings are at increased risk for acute gastroenteritis.1,2 Personal hygiene (eg, frequent hand washing, hand sanitizers, etc.) remains a central strategy. A skin and soft tissue infection (SSTI) prevention trial was conducted among military trainees.3 Trainees were randomized to 1 of 3 groups with incrementally increasing education- and hygiene-based measures. The principal components were promotion of hand washing in addition to a once-weekly application of a chlorhexidine-based body wash. Herein, we report the trial’s impact on acute gastroenteritis.

Background Academic medical centers play a major role in disaster response, and residents frequently serve as key resources in these situations. Studies examining health care professionals' willingness to report for duty in mass casualty situations have varying response rates, and studies of emergency medicine (EM) residents' willingness to report for duty in disaster events and factors that affect these responses are lacking. Objective We sought to determine EM resident and faculty willingness to report for duty during 4 disaster scenarios (natural, explosive, nuclear, and communicable), to identify factors that affect willingness to work, and to assess opinions regarding disciplinary action for physicians unwilling to work in a disaster situation. Methods We surveyed residents and faculty at 7 US teaching institutions with accredited EM residency programs between April and November 2010. Results A total of 229 faculty and 259 residents responded (overall response rate, 75.4%). Willingness to report for duty ranged from 54.1% for faculty in a natural disaster to 94.2% for residents in a nonnuclear explosive disaster. The 3 most important factors influencing disaster response were concern for the safety of the family, belief in the physician's duty to provide care, and availability of protective equipment. Faculty and residents recommended minimal or no disciplinary action for individuals unwilling to work, except in the infectious disease scenario. Conclusions Most EM residents and faculty indicated they would report for duty. Residents and faculty responses were similar in all but 1 scenario. Disciplinary action for individuals unwilling to work generally was not recommended.

CME Educational Objectives 1. Understand the pathophysiology of neurosensory sequelae of mild traumatic brain injury. 2. Understand treatment options for the neurosensory sequelae of mild traumatic brain injury. 3. Understand the interactions of neurosensory sequelae in patients with mild traumatic brain injury. Historically, research to explore traumatic brain injury (TBI) has focused on blunt head trauma, particularly as associated with severe consequences. In this injury pattern, treatment focuses on initial life-saving measurements, intensive care in the hospital, and rehabilitating activities of daily living. 1,2 Far less attention has been focused on mild traumatic brain injury (mTBI).

Vestibular migraine is becoming recognised as a distinct clinical entity that accounts for a high proportion of patients with vestibular symptoms. A temporal overlap between vestibular symptoms, such as vertigo and head-movement intolerance, and migraine symptoms, such as headache, photophobia, and phonophobia, is a requisite diagnostic criterion. Physical examination and laboratory testing are usually normal in vestibular migraine but can be used to rule out other vestibular disorders with overlapping symptoms. The pathophysiology of vestibular migraine is incompletely understood but plausibly could include neuroanatomical pathways to and from central vestibular structures and neurochemical modulation via the locus coeruleus and raphe nuclei. In the absence of controlled trials, treatment options for patients with vestibular migraine largely mirror those for migraine headache.

A cluster-randomized trial evaluating the effectiveness of chlorhexidine gluconate-impregnated wipes against skin and soft tissue infections (SSTIs) and colonization with methicillin-resistant Staphylococcus aureus (MRSA) was conducted among military recruits attending Officer Candidate School at Marine Corps Base Quantico, Virginia. Participants were instructed to use the wipes thrice weekly and were monitored daily for SSTI. Surveys assessed frequency of wipe use as well as knowledge and attitudes regarding MRSA SSTI. Use of chlorhexidine gluconate-impregnated wipes failed to prevent SSTI; however, study adherence was moderate. Adherence with the study regimen (defined as use of > or = 50% of the wipes) was 65% at week 2 and declined to 49% by week 6. Adherence was approximately 59% in the first two classes and declined in later classes. One-third felt that use of the wipes was disruptive. Participants were knowledgeable about MRSA SSTI prevention measures. However, only 53% agreed that MRSA commonly causes skin infections in military training facilities. Understanding adherence and its determinants is needed to optimize prevention strategies that require self-administration. Future efforts should address barriers to adherence with prevention strategies in recruit training settings.

This study provides the first clear evidence that the generation of optokinetic nystagmus fast phases (FPs) is a decision process that is influenced by performance of a concurrent disjunctive reaction time task (DRT). Ten subjects performed an auditory DRT during constant velocity optokinetic stimulation. Eye movements were measured in three dimensions with a magnetic search coil. Slow phase (SP) durations were defined as the interval between FPs. There were three main findings. Firstly, human optokinetic nystagmus SP durations are consistent with a model of a Gaussian basic interval generator (a type of biological clock), such that FPs can be triggered randomly at the end of a clock cycle (mean duration: 200–250 ms). Kolmogorov-Smirnov tests could not reject the modeled cumulative distribution for any data trials. Secondly, the FP need not be triggered at the end of a clock cycle, so that individual SP durations represent single or multiple clock cycles. Thirdly, the probability of generating a FP at the end of each interval generator cycle decreases significantly during performance of a DRT. These findings indicate that the alternation between SPs and FPs of optokinetic nystagmus is not purely reflexive. Rather, the triggering of the next FP is postponed more frequently if a recently presented DRT trial is pending action when the timing cycle expires. Hence, optokinetic nystagmus FPs show dual-task interference in a manner usually attributed to voluntary movements, including saccades. NEW & NOTEWORTHY This study provides the first clear evidence that the generation of optokinetic nystagmus (OKN) fast phases is a decision process that is influenced by performance of a concurrent disjunctive reaction time task (DRT). The slow phase (SP) durations are consistent with a Gaussian basic interval generator and multiple interval SP durations occur more frequently in the presence of the DRT. Hence, OKN shows dual-task interference in a manner observed in voluntary movements, such as saccades.

Traumatic brain injury is an increasingly common public health issue, with the mild variant most clinically relevant for this chapter. Common causes of mild traumatic brain injury (mTBI) include motor vehicle accidents, athletics, and military training/deployment. Despite a range of clinically available testing platforms, diagnosis of mTBI remains challenging. Symptoms are primarily neurosensory, and include dizziness, hearing problems, headaches, cognitive, and sleep disturbances. Dizziness is nearly universally present in all mTBI patients, and is the easiest symptom to objectify for diagnosis. Aside from a thorough history and physical exam, in the near future specialized vestibular function tests will be key to mTBI diagnosis. A battery of oculomotor (antisaccade, predictive saccade) and vestibular tasks (head impulse test) has been demonstrated to sensitively and specifically identify individuals with acute mTBI. Vestibular therapy and rehabilitation have shown improvements for mTBI patients in cognitive function, ability to return to activities of daily living, and ability to return to work. Dizziness, as a contributor to short- and long-term disability following mTBI, is ultimately crucial not only for diagnosis but also for treatment.

Military trainees are at high risk for skin and soft-tissue infections (SSTIs). Although Staphylococcus aureus is associated with purulent SSTI, it is unclear to what degree this pathogen causes nonpurulent cellulitis. To inform effective prevention strategies and to provide novel insights into SSTI pathogenesis, we aimed to determine the etiology of SSTI in this population. We conducted a prospective observational study in US Army Infantry trainees with SSTI (cutaneous abscesses and cellulitis) from July 2012 through December 2014. We used standard microbiology, serology, and high-throughput sequencing to determine the etiology of SSTI. Furthermore, we compared purported risk factors as well as anatomic site colonization for S. aureus. Among 201 SSTI cases evaluated for SSTI risk factors, cellulitis was associated with lower extremity blisters (P = 0.01) and abscess was associated with methicillin-resistant S. aureus (MRSA) colonization (P

The 2011 Model of the Clinical Practice of Emergency Medicine. ACADEMIC EMERGENCY MEDICINE 2012; 19:000–000 © 2012 by the Society for Academic Emergency Medicine

Study objective We characterize and compare the work activities, including peak patient loads, associated with the workplace in the academic and community emergency department (ED) settings. This allows assessment of the effect of future ED system operational changes and identifies potential sources contributing to medical error. Methods This was an observational, time-motion study. Trained observers shadowed physicians, recording activities. Data included total interactions, distances walked, time sitting, patients concurrently treated, interruptions, break in tasks, physical contact with patients, hand washing, diagnostic tests ordered, and therapies rendered. Activities were classified as direct patient care, indirect patient care, or personal time with a priori definitions. Results There were 203 2-hour observation periods of 85 physicians at 2 academic EDs with 100,000 visits per year at each (N=160) and 2 community EDs with annual visits of 19,000 and 21,000 (N=43). Reported data present the median and minimum-maximum values per 2-hour period. Emergency physicians spent the majority of time on indirect care activities (academic 64 minutes, 29 to 91 minutes; community 55 min, 25 to 95 minutes), followed by direct care activities (academic 36 minutes, 6 to 79 minutes; community 41 minutes, 5 to 60 minutes). Personal time differed by location type (academic 6 minutes, 0 to 66 minutes; community 13 minutes, 0 to 69 minutes). All physicians simultaneously cared for multiple patients, with a median number of patients greater than 5 (academic 7 patients, 2 to 16 patients; community 6 patients, 2 to 12 patients). Conclusion Emergency physicians spend the majority of their time involved in indirect patient care activities. They are frequently interrupted and interact with a large number of individuals. They care for a wide range of patients simultaneously, with surges in multiple patient care responsibilities. Physicians working in academic settings are interrupted at twice the rate of their community counterparts.