Effects of multimodal explanations for autonomous driving on driving performance, cognitive load, expertise, confidence, and trust.

Advances in autonomous driving provide an opportunity for AI-assisted driving instruction that directly addresses the critical need for human driving improvement. How should an AI instructor convey information to promote learning? In a pre-post experiment (n = 41), we tested the impact of an AI Coach's explanatory communications modeled after performance driving expert instructions. Participants were divided into four (4) groups to assess two (2) dimensions of the AI coach's explanations: information type ('what' and 'why'-type explanations) and presentation modality (auditory and visual). We compare how different explanatory techniques impact driving performance, cognitive load, confidence, expertise, and trust via observational learning. Through interview, we delineate participant learning processes. Results show AI coaching can effectively teach performance driving skills to novices. We find the type and modality of information influences performance outcomes. Differences in how successfully participants learned are attributed to how information directs attention, mitigates uncertainty, and influences overload experienced by participants. Results suggest efficient, modality-appropriate explanations should be opted for when designing effective HMI communications that can instruct without overwhelming. Further, results support the need to align communications with human learning and cognitive processes. We provide eight design implications for future autonomous vehicle HMI and AI coach design.

Association of Radiology Findings with Etiology of Community Acquired Pneumonia among Children.

OBJECTIVE: To evaluate the association between consolidation on chest radiograph and typical bacterial etiology of childhood community acquired pneumonia (CAP) in the Etiology of Pneumonia in the Community study. STUDY DESIGN: Hospitalized children <18 years of age with CAP enrolled in the Etiology of Pneumonia in the Community study at 3 children's hospitals between January 2010 and June 2012 were included. Testing of blood and respiratory specimens used multiple modalities to identify typical and atypical bacterial, or viral infection. Study radiologists classified chest radiographs (consolidation, other infiltrates [interstitial and/or alveolar], pleural effusion) using modified World Health Organization pneumonia criteria. Infiltrate patterns were compared according to etiology of CAP. RESULTS: Among 2212 children, there were 1302 (59%) with consolidation with or without other infiltrates, 910 (41%) with other infiltrates, and 296 (13%) with pleural effusion. In 1795 children, at least 1 pathogen was detected. Among these patients, consolidation (74%) was the most frequently observed pattern (74% in typical bacterial CAP, 58% in atypical bacterial CAP, and 54% in viral CAP). Positive and negative predictive values of consolidation for typical bacterial CAP were 12% (95% CI 10%-15%) and 96% (95% CI 95%-97%) respectively. In a multivariable model, typical bacterial CAP was associated with pleural effusion (OR 7.3, 95% CI 4.7-11.2) and white blood cell ≥15 000/mL (OR 3.2, 95% CI 2.2-4.9), and absence of wheeze (OR 0.5, 95% CI 0.3-0.8) or viral detection (OR 0.2, 95% CI 0.1-0.4). CONCLUSIONS: Consolidation predicted typical bacterial CAP poorly, but its absence made typical bacterial CAP unlikely. Pleural effusion was the best predictor of typical bacterial infection, but too uncommon to aid etiology prediction.

Utility of Induced Sputum in Assessing Bacterial Etiology for Community-Acquired Pneumonia in Hospitalized Children.

BACKGROUND: Diagnostic testing for bacterial etiology of community-acquired pneumonia (CAP) is insensitive. Induced sputum (IS) is an attractive option for the evaluation of the lower respiratory tract. METHODS: Children aged 0-18 years with CAP were enrolled in the Etiology of Pneumonia in the Community (EPIC) study between 2010 and 2012. Blood and respiratory specimens were assessed by culture and polymerase chain reaction (PCR). The radiographic CAP was determined by a study radiologist. Sputum was induced with hypertonic saline. IS specimen was high quality (HQ) if Gram stain showed >25 white blood and <10 epithelial cells per low-powered field; all others were low quality (LQ). We compared IS pathogen prevalence between HQ and LQ IS, and by radiographic pneumonia. Pathogen concordance with EPIC etiology was assessed. Length of stay (LOS) was compared by receipt of IS pathogen-concordant antibiotics. RESULTS: Out of 977 children, 916 (94%) children enrolled in Memphis, Tennessee, produced IS; 794 (87%) had radiographic CAP and 174 (19%) were HQ. HQ IS yielded pathogenic bacteria more often than LQ (64% vs 44%; P < .01); however, pathogens were isolated at similar rates in HQ IS in patients with and without radiographic CAP (64% vs. 63%; P = .6). Pathogens from study specimens matched an IS pathogen in only 9/42 (21%) patients with radiographic CAP. Median LOS was similar among patients with radiographic CAP regardless of receipt of IS pathogen-concordant antibiotics (3.1 days), non-pathogen-concordant antibiotics (2.7 days), or no antibiotics (3.2 days; P = .5). CONCLUSIONS: Bacterial pathogens were isolated from most IS cultures regardless of radiographic CAP and quality of IS. IS cultures infrequently corresponded with sterile site cultures. Isolation of pathogens from pediatric IS reflects oropharyngeal carriage and is insufficient to determine bacterial etiology of CAP.

Mindfulness Training Improves Cognition and Strengthens Intrinsic Connectivity Between the Hippocampus and Posteromedial Cortex in Healthy Older Adults.

Maintaining optimal cognitive functioning throughout the lifespan is a public health priority. Evaluation of cognitive outcomes following interventions to promote and preserve brain structure and function in older adults, and associated neural mechanisms, are therefore of critical importance. In this randomized controlled trial, we examined the behavioral and neural outcomes following mindfulness training (n = 72), compared to a cognitive fitness program (n = 74) in healthy, cognitively normal, older adults (65-80 years old). To assess cognitive functioning, we used the Preclinical Alzheimer Cognitive Composite (PACC), which combines measures of episodic memory, executive function, and global cognition. We hypothesized that mindfulness training would enhance cognition, increase intrinsic functional connectivity measured with magnetic resonance imaging (MRI) between the hippocampus and posteromedial cortex, as well as promote increased gray matter volume within those regions. Following the 8-week intervention, the mindfulness training group showed improved performance on the PACC, while the control group did not. Furthermore, following mindfulness training, greater improvement on the PACC was associated with a larger increase in intrinsic connectivity within the default mode network, particularly between the right hippocampus and posteromedial cortex and between the left hippocampus and lateral parietal cortex. The cognitive fitness training group did not show such effects. These findings demonstrate that mindfulness training improves cognitive performance in cognitively intact older individuals and strengthens connectivity within the default mode network, which is particularly vulnerable to aging affects. Clinical Trial Registration: [https://clinicaltrials.gov/ct2/show/NCT02628548], identifier [NCT02628548].

The use of imaging to identify immunocompromised children requiring biopsy for invasive fungal rhinosinusitis.

BACKGROUND AND PURPOSE: Children with severe immunocompromise due to cancer therapy or hematopoietic cell transplant are at risk both for potentially lethal invasive fungal rhinosinusitis (IFRS), and for complications associated with gold-standard biopsy diagnosis. We investigated whether early imaging could reliably identify or exclude IFRS in this population, thereby reducing unnecessary biopsy. METHODS: We reviewed clinical/laboratory data and cross-sectional imaging from 31 pediatric patients evaluated for suspicion of IFRS, 19 without (age 11.8 ± 5.4 years) and 12 with proven IFRS (age 11.9 ± 4.6 years). Imaging examinations were graded for mucosal thickening (Lund score), for fungal-specific signs (FSS) of bone destruction, extra-sinus inflammation, and nasal mucosal ulceration. Loss of contrast enhancement (LoCE) was assessed separately where possible. Clinical and imaging findings were compared with parametric or nonparametric tests as appropriate. Diagnostic accuracy was assessed by receiver operating characteristic (ROC) analysis. Positive (+LR) and negative likelihood ratios (-LR) and probabilities were calculated. RESULTS: Ten of 12 patients with IFRS and one of 19 without IFRS had at least one FSS on early imaging (83% sensitive, 95% specific, +LR = 15.83, -LR = 0.18; P < .001). Absolute neutrophil count (ANC) ≤ 200/mm3 was 100% sensitive and 58% specific for IFRS (+LR = 2.38, -LR = 0; P = .001). Facial pain was the only discriminating symptom of IFRS (P < .001). In a symptomatic child with ANC ≤ 200/m3 , the presence of at least one FSS indicated high (79%) probability of IFRS; absence of FSS suggested low (<4%) probability. CONCLUSION: In symptomatic, severely immunocompromised children, the presence or absence of fungal-specific imaging findings may effectively rule in or rule out early IFRS, potentially sparing some patients the risks associated with biopsy.

Trends in gabapentin and baclofen exposures reported to U.S. poison centers.

Context: Prescriptions for nonopioid pharmacological therapies such as gabapentin and baclofen have been increasing. While gabapentin and baclofen are less likely than opioids to result in fatal overdose, they are each associated with dependence, misuse and adverse effects.Objective: The objective of this study is to evaluate and describe trends in adult exposures to gabapentin and baclofen reported to U.S. Poison Centers.Methods: This was a retrospective review of data collected by U.S. Poison Centers and entered in the National Poison Data System. We identified all cases of exposures to gabapentin (2013-2017) and baclofen (2014-2017) in patients aged 18 years and over. We then analyzed demographics, common co-ingestions, medical outcomes, and geographic distribution.Results: During the five-year period (2013-2017), there were 74,175 gabapentin exposures. All gabapentin exposures increased by 72.3%; isolated exposures increased by 67.1%; and isolated abuse/misuse exposures increased by 119.9%. During the four-year period (2014-2017), there were 15,397 baclofen exposures. All baclofen exposures increased by 36.2%; isolated exposures increased by 35.0%; and isolated abuse/misuse exposures increased by 31.7%. Co-ingestions of sedatives and opioids were common for both medications. Admissions to a health care facility were required in 16.7% of isolated gabapentin exposures, and 52.1% of isolated baclofen exposures. Intentional suspected suicide attempts with isolated gabapentin exposures increased by 80.5% over a five-year period; and increased by 43% for isolated baclofen exposures over a four-year period. All states saw increases in gabapentin exposures and most states saw increases in baclofen exposures, gabapentin misuse/abuse, and baclofen misuse/abuse.Conclusion: Gabapentin and baclofen misuse, toxicity, use in suicide attempts, and associated healthcare utilization among adults in the United States have significantly increased since 2013. Careful consideration and risk-benefit analysis should be employed when prescribing these medications.

Managing Acute Pain and Opioid Risks Following Wisdom Teeth Extraction: An Illustrative Case.

Introduction: The opioid epidemic has awakened educators to the insufficiency of training in the areas of pain management and substance use disorders within the curricula of health sciences schools. The University of Pittsburgh Center of Excellence in Pain Education created an online educational module focusing on factors contributing to the opioid epidemic and the role of robust interprofessional communication in avoiding common practitioner errors. Methods: The 1-hour module created by an interprofessional team comprised a pretest, video presentation featuring case vignettes, posttest, and learner satisfaction survey. The content of the module focused on four core concepts: (1) managing acute perioperative pain, (2) maximizing opioid safety, and (3) identifying and (4) managing suspected opioid abuse and diversion. Results: Data were obtained from 250 dental, pharmacy, and nursing students from the University of Pittsburgh who completed the module as part of their respective profession-specific curricula. Results collapsed across the three school-specific implementations indicated an average increase in knowledge test scores from pre- to posttest (Z = -8.82, p < .001). In addition, the learner satisfaction data revealed an overall positive response to the module, with students commenting that they enjoyed the module and felt it provided them with a valuable learning experience. Discussion: Learner outcomes and feedback suggest that our interprofessional team was successful in creating an effective learning module applicable to several health care professions, namely, pharmacy, dentistry, and nursing. Future studies might address the application of the knowledge gained to actual patient care.

Integration of Medication-Assisted Treatment Information for Opioid Use Disorders Into a Graduate Nursing Curriculum.

PURPOSE: The United States is in the midst of an unprecedented public health crisis, with annual morbidity and mortality data related to opioid use consistently increasing and appearing more worrisome. To mitigate such consequences, it is critical that those with opioid use disorders are provided with and have access to evidence-based treatment modalities. METHODS: The project utilized a course scaffolding approach to integrate a comprehensive substance use framework into an advanced practice nursing curriculum, with an emphasis on medication-assisted treatment as part of an advanced pharmacology course required for licensure. RESULTS: Students' knowledge assessment increased significantly, from an average of 2.82 to 3.78 out of 5 items, t(217) = -10.31, p < .01. CONCLUSIONS: Educators and academic administrators must be steadfast in their resolve to include substance use, and specifically opioid use, education into all areas and levels of nursing study.

Fully automated tissue classifier for contrast-enhanced CT scans of adult and pediatric patients.

To develop a consistent, fully-automated classifier for all tissues within the trunk and to more accurately discriminate between tissues (such as bone) and contrast medium with overlapping high CT numbers. Twenty-eight contrast enhanced NCAP (neck-chest-abdomen-pelvis) CT scans (four adult and three pediatric patients) were used to train and test a tissue classification pipeline. The classifier output consisted of six tissue classes: lung, fat, muscle, solid organ, blood/bowel contrast and bone. The input features for training were selected from 28 2D image filters and 12 3D filters, and one hand crafted spatial feature. To improve differentiation between tissue and blood/bowel contrast classification, 70 additional CT images were manually classified. Two different training data sets consisting of manually classified tissues from different locations in body were used to train the models. Training used the random forest algorithm in WEKA (Waikato Environment for Knowledge Analysis); the number of trees was optimized for best out-of-bag error. Automated classification accuracy was compared with manual classification by calculating dice similarity coefficient (DSC). Model performance was tested on 21 manually classified slices (two adult and one pediatric patient). The overall DSC at image locations represented in the training dataset were-lung: 0.98, fat: 0.90, muscle: 0.85, solid organ: 0.75, blood/contrast: 0.82, and bone: 0.90. The overall DSC for slice locations that were not represented in the training dataset were-lung: 0.97, fat: 0.89, muscle: 0.76, solid organ: 0.79, blood: 0.56, and bone: 0.74. Analyzing the classification maps for the entire scan volume revealed that except for misclassifications in the trabecular bone region of the spinal column, and solid organ and blood/contrast interfaces within the abdomen, the results were acceptable. A fully-automated whole-body tissue classifier for adult and pediatric contrast-enhanced CT using random forest algorithm and intensity-based image filters was developed.

Severe soft tissue injuries of the upper extremity in motor vehicle crashes involving partial ejection: the protective role of side curtain airbags.

INTRODUCTION: Partial ejection (PE) of the upper extremity (UE) can occur in a motor vehicle crash (MVC) resulting in complex and severe soft tissue injuries (SSTI). This study evaluated the relationship between partial ejection and UE injuries, notably SSTIs, in MVCs focusing on crash types and characteristics, and further examined the role of side curtain airbags (SCABs) in the prevention of partial ejection and reducing SSTI of the UE. METHODS: Weighted data was analyzed from the National Automotive Sampling System Crashworthiness Data System (NASS-CDS) from 1993 to 2012. Logistic regression models were used to assess the relationship of PE with SSTI of the UE and the effect of SCABs in both nearside impacts and rollover collisions. Crash Injury Research and Engineering Network (CIREN) case studies illustrated PE involving SSTI of the UE, and long term treatment. RESULTS: Rollover and nearside impact collisions had the highest percentages of partial ejection, with over half occurring in rollover collisions. Annually over 800 SSTIs of the UE occurred in all MVCs. For nearside lateral force impacts, a multivariable analysis adjusting for belt use and delta V showed a 15 times (OR 15.35, 95% CI 4.30, 54.79) greater odds of PE for occupants without SCABs compared to those with a SCAB deployment. No occupants (0 of 51,000) sustained a SSTI of the UE when a SCAB deployed in nearside impacts, compared to 0.01% (114 of 430,000) when SCABs were unavailable or did not deploy. In rollover collisions, a multivariable analysis adjusted for number of quarter turns and belt use showed 3 times the odds (OR 3.02, 95% CI 1.22, 7.47) of PE for occupants without SCABs compared to those with a SCAB deployment. Just 0.17% (32 of 19,000) of the occupants sustained a SSTI of the UE in rollovers with a SCAB deployment, compared to 0.53% (2294 of 431,000) of the occupants when SCABs were unavailable or did not deploy. CIREN case studies illustrated the injury causation of SSTI of the UE due to partial ejection, and the long term treatment and medical costs associated with a SSTI to the UE. CONCLUSIONS: The majority of severe soft tissue injuries (SSTI) of the upper extremity (UE) involved partial ejection out the nearside window of outboard seated occupants in nearside impacts and rollover collisions. Real world case studies showed that SSTIs of the upper extremity require extensive treatment, extended hospitalization and are costly. Occupants without a side curtain airbag (SCAB) deployment had an increase in the odds of partial ejection. SCAB deployments provided protection against partial ejection and prevented SSTIs of the UE, with none occurring in nearside impacts, and a small percentage and reduction occurring in rollover collisions compared to those where SCABs were unavailable or did not deploy.

Evaluating the Potential Benefits of Advanced Automatic Crash Notification.

OBJECTIVE: Advanced Automatic Collision Notification (AACN) services in passenger vehicles capture crash data during collisions that could be transferred to Emergency Medical Services (EMS) providers. This study explored how EMS response times and other crash factors impacted the odds of fatality. The goal was to determine if information transmitted by AACN could help decrease mortality by allowing EMS providers to be better prepared upon arrival at the scene of a collision. METHODS: The Crash Injury Research and Engineering Network (CIREN) database of the US Department of Transportation/National Highway Traffic Safety Administration (USDOT/NHTSA; Washington DC, USA) was searched for all fatal crashes between 1996 and 2012. The CIREN database also was searched for illustrative cases. The NHTSA's Fatal Analysis Reporting System (FARS) and National Automotive Sampling System Crashworthiness Data System (NASS CDS) databases were queried for all fatal crashes between 2000 and 2011 that involved a passenger vehicle. Detailed EMS time data were divided into prehospital time segments and analyzed descriptively as well as via multiple logistic regression models. RESULTS: The CIREN data showed that longer times from the collision to notification of EMS providers were associated with more frequent invasive interventions within the first three hours of hospital admission and more transfers from a regional hospital to a trauma center. The NASS CDS and FARS data showed that rural collisions with crash-notification times >30 minutes were more likely to be fatal than collisions with similar crash-notification times occurring in urban environments. The majority of a patient's prehospital time occurred between the arrival of EMS providers on-scene and arrival at a hospital. The need for extrication increased the on-scene time segment as well as total prehospital time. CONCLUSION: An AACN may help decrease mortality following a motor vehicle collision (MVC) by alerting EMS providers earlier and helping them discern when specialized equipment will be necessary in order to quickly extricate patients from the collision site and facilitate expeditious transfer to an appropriate hospital or trauma center. Plevin RE , Kaufman R , Fraade-Blanar L , Bulger EM . Evaluating the potential benefits of advanced automatic crash notification. Prehosp Disaster Med. 2017;32(2):156-164.

"I wasn't texting; I was just reading an email ": a qualitative study of distracted driving enforcement in Washington State.

BACKGROUND: In response to the rise of distracted driving, many countries and most US states have adopted laws to restrict the use of handheld phones for drivers. Specific provisions of each law and the overall social mores of distracted driving influence enforceability and impact. OBJECTIVES: Identify multilevel interdependent factors that influence distracted driving enforcement through the perspective of police officers. DESIGN/METHODS: We conducted focus group discussions with active duty law enforcement officers from three large Washington State counties. Our thematic analysis used descriptive and pattern coding that placed our findings within a social ecological framework to facilitate targeted intervention development. RESULTS: Participants reported that the distracted driving law posed challenges for consistent and effective enforcement. They emphasised the need to change social norms around distracted driving, similar to the shifts seen around impaired driving. Many participants were themselves distracted drivers, and their individual knowledge, attitude and beliefs influenced enforcement. Participants suggested that law enforcement leaders and policymakers should develop and implement policies and strategies to prioritise and motivate increased distracted driving enforcement. CONCLUSIONS: Individual, interpersonal, organisational and societal factors influence enforcement of distracted driving laws. Targeted interventions should be developed to address distracted driving and sustain effective enforcement.

Tissue segmentation of computed tomography images using a Random Forest algorithm: a feasibility study.

There is a need for robust, fully automated whole body organ segmentation for diagnostic CT. This study investigates and optimizes a Random Forest algorithm for automated organ segmentation; explores the limitations of a Random Forest algorithm applied to the CT environment; and demonstrates segmentation accuracy in a feasibility study of pediatric and adult patients. To the best of our knowledge, this is the first study to investigate a trainable Weka segmentation (TWS) implementation using Random Forest machine-learning as a means to develop a fully automated tissue segmentation tool developed specifically for pediatric and adult examinations in a diagnostic CT environment. Current innovation in computed tomography (CT) is focused on radiomics, patient-specific radiation dose calculation, and image quality improvement using iterative reconstruction, all of which require specific knowledge of tissue and organ systems within a CT image. The purpose of this study was to develop a fully automated Random Forest classifier algorithm for segmentation of neck-chest-abdomen-pelvis CT examinations based on pediatric and adult CT protocols. Seven materials were classified: background, lung/internal air or gas, fat, muscle, solid organ parenchyma, blood/contrast enhanced fluid, and bone tissue using Matlab and the TWS plugin of FIJI. The following classifier feature filters of TWS were investigated: minimum, maximum, mean, and variance evaluated over a voxel radius of 2 (n) , (n from 0 to 4), along with noise reduction and edge preserving filters: Gaussian, bilateral, Kuwahara, and anisotropic diffusion. The Random Forest algorithm used 200 trees with 2 features randomly selected per node. The optimized auto-segmentation algorithm resulted in 16 image features including features derived from maximum, mean, variance Gaussian and Kuwahara filters. Dice similarity coefficient (DSC) calculations between manually segmented and Random Forest algorithm segmented images from 21 patient image sections, were analyzed. The automated algorithm produced segmentation of seven material classes with a median DSC of 0.86 ± 0.03 for pediatric patient protocols, and 0.85 ± 0.04 for adult patient protocols. Additionally, 100 randomly selected patient examinations were segmented and analyzed, and a mean sensitivity of 0.91 (range: 0.82-0.98), specificity of 0.89 (range: 0.70-0.98), and accuracy of 0.90 (range: 0.76-0.98) were demonstrated. In this study, we demonstrate that this fully automated segmentation tool was able to produce fast and accurate segmentation of the neck and trunk of the body over a wide range of patient habitus and scan parameters.

An intervention to maximize medication management by caregivers of persons with memory loss: Intervention overview and two-month outcomes.

Overseeing medication-taking is a critical aspect of dementia caregiving. This trial examined a tailored, problem-solving intervention designed to maximize medication management practices among caregivers of persons with memory loss. Eighty-three community-dwelling dyads (patient + informal caregiver) with a baseline average of 3 medication deficiencies participated. Home- and telephone-based sessions were delivered by nurse or social worker interventionists and addressed basics of managing medications, plus tailored problem solving for specific challenges. The outcome of medication management practices was assessed using the Medication Management Instrument for Deficiencies in the Elderly (MedMaIDE) and an investigator-developed Medication Deficiency Checklist (MDC). Linear mixed modeling showed both the intervention and usual care groups had fewer medication management problems as measured by the MedMaIDE (F = 6.91, p < .01) and MDC (F = 9.72, p < .01) at 2 months post-intervention. Reduced medication deficiencies in both groups suggests that when nurses or social workers merely raise awareness of the importance of medication adherence, there may be benefit.

Beyond BRCA: A Pilot Program to Assess and Improve Knowledge of Pharmacogenomic Testing Among Advanced Practitioners in a Breast Cancer Treatment Setting.

To provide the best available evidence-based care to their patients, advanced practitioners (APs) must become proficient in genomic competencies and remain informed regarding the availability of pharmacogenomic tests. Databases, such as the Centers for Disease Control and Prevention's "Genomic Testing," provide guidance about pharmacogenomic testing, but many APs are not aware of these resources. This study employed a quasi-experimental pretest/posttest design using a convenience sample of APs in a large clinical outpatient breast cancer clinic to assess the knowledge base, beliefs, attitudes, and barriers regarding pharmacogenomic testing among front-line APs and increase knowledge through a targeted educational intervention. The objectives of the educational intervention were to (1) increase knowledge of the clinical indication for testing; (2) increase collaboration among the interprofessional team; and (3) identify correctly when the plan of care should be modified based on pharmacogenomic test results to optimize patient outcomes. Responses showed that these oncology APs possess a strong foundation in genetics and support the addition of new pharmacogenomic tests to their practice.

Distinguishing Osteomyelitis From Ewing Sarcoma on Radiography and MRI.

OBJECTIVE: The purpose of this study was to determine whether clinical and imaging features can distinguish osteomyelitis from Ewing sarcoma (EWS) and to assess the accuracy of percutaneous biopsy versus open biopsy in the diagnosis of these diseases. MATERIALS AND METHODS: Three radiologists reviewed the radiographs and MRI examinations of 32 subjects with osteomyelitis and 31 subjects with EWS to determine the presence of 36 imaging parameters. Information on demographic characteristics, history, physical examination findings, laboratory findings, biopsy type, and biopsy results were recorded. Individual imaging and clinical parameters and combinations of these parameters were tested for correlation with findings from histologic analysis. The diagnostic accuracy of biopsy was also determined. RESULTS: On radiography, the presence of joint or metaphyseal involvement, a wide transition zone, a Codman triangle, a periosteal reaction, or a soft-tissue mass, when tested individually, was more likely to be noted in subjects with EWS (p ≤ 0.05) than in subjects with osteomyelitis. On MRI, permeative cortical involvement and soft-tissue mass were more likely in subjects with EWS (p ≤ 0.02), whereas a serpiginous tract was more likely to be seen in subjects with osteomyelitis (p = 0.04). African Americans were more likely to have osteomyelitis than EWS (p = 0). According to the results of multiple regression analysis, only ethnicity and soft-tissue mass remained statistically significant (p ≤ 0.01). The findings from 100% of open biopsies (18/18) and 58% of percutaneous biopsies (7/12) resulted in the diagnosis of osteomyelitis, whereas the findings from 88% of open biopsies (22/25) and 50% of percutaneous biopsies (3/6) resulted in a diagnosis of EWS. CONCLUSION: Several imaging features are significantly associated with either EWS or osteomyelitis, but many features are associated with both diseases. Other than ethnicity, no clinical feature improved diagnostic accuracy. Compared with percutaneous biopsy, open biopsy provides a higher diagnostic yield but may be inconclusive, especially for cases of EWS. Our findings underscore the need for better methods of diagnosing these disease processes.

A Comprehensive Risk Assessment Method for Pediatric Patients Undergoing Research Examinations Using Ionizing Radiation: How We Answered the Institutional Review Board.

OBJECTIVE: The objectives of this study are to establish a comprehensive method for radiation dose estimates for the most common imaging examinations performed for research, for internal use of institutional review board (IRB) and radiation safety committees; to provide investigators with relative examination doses so that they may better assess the potential radiation effects and risks for research subjects; and to provide simplified language that investigators can use in consent documents. MATERIALS AND METHODS: Nineteen common radiation-based examinations used in clinical research at our institution were identified. For each modality (CT, digital radiography, dual-energy x-ray absorptiometry, PET/CT, and nuclear medicine), a comprehensive patient-specific dosimetry method was established. Effective dose was calculated according to average population calculated doses for the following age groups: 0-1, 2-8, 9-13, 14-15, and older than 15 years. RESULTS: Estimated effective dose values were tabulated and posted on our institutional IRB intranet site for use by IRB and radiation safety committee members and institutional investigators. Relative examination dose levels were compared for all ages and for all examinations. A three-tiered approach to establish consent language for radiation exposure was established for research subjects receiving an effective dose less than 3 mSv, a dose between 3 and 50 mSv, and a dose greater than 50 mSv. CONCLUSION: The method to estimate effective dose was tabulated for 19 of the most common ionizing radiation examinations at our institute. These results will act as a resource to help investigators better understand the implications of radiation exposure in research and can assist investigators in protocol development and correct categorization of radiation exposure risk.

How to Appropriately Calculate Effective Dose for CT Using Either Size-Specific Dose Estimates or Dose-Length Product.

OBJECTIVE: The purpose of this study is to show how to calculate effective dose in CT using size-specific dose estimates and to correct the current method using dose-length product (DLP). MATERIALS AND METHODS: Data were analyzed from 352 chest and 241 abdominopelvic CT images. Size-specific dose estimate was used as a surrogate for organ dose in the chest and abdominopelvic regions. Organ doses were averaged by patient weight-based populations and were used to calculate effective dose by the International Commission on Radiological Protection (ICRP) report 103 method using tissue-weighting factors (EICRP). In addition, effective dose was calculated using population-averaged CT examination DLP for the chest and abdominopelvic region using published k-coefficients (EDLP = k × DLP). RESULTS: EDLP differed from EICRP by an average of 21% (1.4 vs 1.1) in the chest and 42% (2.4 vs 3.4) in the abdominopelvic region. The differences occurred because the published kcoefficients did not account for pitch factor other than unity, were derived using a 32-cm diameter CT dose index (CTDI) phantom for CT examinations of the pediatric body, and used ICRP 60 tissue-weighting factors. Once it was corrected for pitch factor, the appropriate size of CTDI phantom, and ICRP 103 tissue-weighting factors, EDLP improved in agreement with EICRP to better than 7% (1.4 vs 1.3) and 4% (2.4 vs 2.5) for chest and abdominopelvic regions, respectively. CONCLUSION: Current use of DLP to calculate effective dose was shown to be deficient because of the outdated means by which the k-coefficients were derived. This study shows a means to calculate EICRP using patient size-specific dose estimate and how to appropriately correct EDLP.