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PURPOSE: The purpose of this study was to assess the effect of obesity and iterative reconstruction on the ability to reduce exposure by studying the accuracy for detection of low-contrast low-attenuation (LCLA) liver lesions on computed tomography (CT) using a phantom model. METHODS: A phantom with four unique LCLA liver lesions (5- to 15-mm spheres, -24 to -6 HU relative to 90-HU background) was scanned without ("thin" phantom) and with ("obese" phantom) a 5-cm thick fat-attenuation ring at 150 mAs (thin phantom) and 450 mAs (obese phantom) standard exposures and at 33% and 67% exposure reductions. Images were reconstructed using standard filtered back projection (FBP) and with iterative reconstruction (Adaptive Model-Based Iterative Reconstruction strength 3, ADMIRE). A noninferiority analysis of lesion detection was performed. RESULTS: Mean area under the curve (AUC) values for lesion detection were significantly higher for the thin phantom than for the obese phantom regardless of exposure level (P < 0.05) for both FBP and ADMIRE. At 33% exposure reduction, AUC was noninferior for both FBP and ADMIRE strength 3 (P < 0.0001). At 67% exposure reduction, AUC remained noninferior for the thin phantom (P < 0.0035), but was no longer noninferior for the obese phantom (P ≥ 0.7353). There were no statistically significant differences in AUC between FBP and ADMIRE at any exposure level for either phantom. CONCLUSIONS: Accuracy for lesion detection was not only significantly lower in the obese phantom at all relative exposures, but detection accuracy decreased sooner while reducing the exposure in the obese phantom. There was no significant difference in lesion detection between FBP and ADMIRE at equivalent exposure levels for either phantom.
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Algoritmos , Neoplasias Hepáticas , Humanos , Obesidad , Fantasmas de Imagen , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por ComputadorRESUMEN
OBJECTIVE: The objective of this study was to compare reader accuracy detecting lesions near hardware in a CT phantom model at different radiation exposures using an advanced metal artifact reduction (MAR) algorithm and standard filtered back projection (FBP) techniques and to determine if radiation exposure could be decreased using MAR without compromising lesion detectability. MATERIALS AND METHODS: A CT phantom manufactured with spherical lesions of various sizes (10-20 mm) and attenuations (20-50 HU) embedded around cobalt-chromium spheres attached to titanium rods, simulating an arthroplasty, was scanned on a single CT scanner (FLASH, Siemens Healthcare) at 140 kVp and 0.6-mm collimation using clinical-dose (300 Quality Reference mAs [Siemens Healthcare]), low-dose (150 Quality Reference mAs), and high-dose (600 Quality Reference mAs) protocols. Images reconstructed with iterative MAR, advanced modeled iterative reconstruction (ADMIRE), and FBP with identical parameters were anonymized and independently reviewed by three radiologists. Accuracies for detecting lesions, measured as AUC, sensitivity, and specificity, were compared. RESULTS: Accuracy using MAR was significantly higher than that using FBP at all exposures (p values ranged from < 0.001 to 0.021). Sensitivity was also higher for MAR than for FBP at all exposures. Specificity was very high for both reconstruction techniques at all exposures with no significant differences. Accuracy of low-dose MAR was higher than and not inferior to standard-dose and high-dose FBP. MAR was significantly more sensitive than FBP in detecting smaller lesions (p = 0.021) and lesions near high streak artifact (p < 0.001). CONCLUSION: MAR improves reader accuracy to detect lesions near hardware and allows significant reductions in radiation exposure without compromising accuracy compared with FBP in a CT phantom model.
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Artefactos , Metales , Prótesis e Implantes , Dosis de Radiación , Protección Radiológica/métodos , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Humanos , Variaciones Dependientes del Observador , Fantasmas de ImagenRESUMEN
OBJECTIVES: The purpose of this study was to evaluate the impact of attenuation-based kilovoltage (kV) pair selection in dual source dual energy (DSDE)-pulmonary embolism (PE) protocol examinations on radiation dose savings and image quality. METHODS: A prospective study was carried out on 118 patients with suspected PE. In patients in whom attenuation-based kV pair selection selected the 80/140Sn kV pair, the pre-scan 100/140Sn CTDIvol (computed tomography dose index volume) values were compared with the pre-scan 80/140Sn CTDIvol values. Subjective and objective image quality parameters were assessed. RESULTS: Attenuation-based kV pair selection switched to the 80/140Sn kV pair ("switched" cohort) in 63 out of 118 patients (53%). The mean 100/140Sn pre-scan CTDIvol was 8.8 mGy, while the mean 80/140Sn pre-scan CTDIvol was 7.5 mGy. The average estimated dose reduction for the "switched" cohort was 1.3 mGy (95% CI 1.2, 1.4; p < 0.001), representing a 15% reduction in dose. After adjusting for patient weight, mean attenuation was significantly higher in the "switched" vs. "non-switched" cohorts in all five pulmonary arteries and in all lobes on iodine maps. CONCLUSIONS: This study demonstrates that attenuation-based kV pair selection in DSDE examination is feasible and can offer radiation dose reduction without compromising image quality. KEY POINTS: ⢠Attenuation-based kV pair selection in dual energy examination is feasible. ⢠It can offer radiation dose reduction to approximately 50% of patients. ⢠Approximate 15% reduction in radiation dose was achieved using this technique. ⢠The image quality is not compromised by use of attenuation-based kV pair selection.
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Angiografía por Tomografía Computarizada/métodos , Angiografía por Tomografía Computarizada/normas , Embolia Pulmonar/diagnóstico por imagen , Dosis de Radiación , Radiografía Torácica/métodos , Radiografía Torácica/normas , Adulto , Anciano , Peso Corporal , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Arteria Pulmonar/diagnóstico por imagenRESUMEN
BACKGROUND: This study sought to examine the relationship between tobacco-free policies at worksites to worksite demographics such as company size and geographic location. METHODS: Worksites participating in a worksite wellness workshop were asked to complete a worksite wellness instrument, which provided an assessment of their wellness practices already in place in the worksite, including the degree to which tobacco-free policies were in place at the worksite. RESULTS: At a bivariate level, those more likely to have tobacco-free policies included: urban employers (76.8% versus 50% rural employers, p = 0.0001); large employers (> = 250 employees) (74.3% versus 43.1% small employers (<50 employees), p = 0.0003); and schools (69.4%) and hospitals (61.5%) (versus 35.5%, agricultural/ manufacturing employers, p = 0.0125). At the multivariate level, rural employers (AOR = 0.47, 95% CI 0.23, 0.95) and small employers (AOR = 0.34, 95% CI 0.16, 0.71) had decreased odds, compared to their urban and large employer counterparts, of having tobacco-free policies. CONCLUSIONS: Rural and smaller employers are less likely to have tobacco-free policies than their urban and large counterparts.
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Política Organizacional , Política para Fumadores , Contaminación por Humo de Tabaco/prevención & control , Lugar de Trabajo/estadística & datos numéricos , Promoción de la Salud , Humanos , Kansas , Salud Laboral , Características de la ResidenciaRESUMEN
Purpose To assess image noise, contrast-to-noise ratio (CNR) and detectability of low-contrast, low-attenuation liver lesions in a semianthropomorphic phantom by using either a discrete circuit (DC) detector and filtered back projection (FBP) or an integrated circuit (IC) detector and iterative reconstruction (IR) with changes in radiation exposure and phantom size. Materials and Methods An anthropomorphic phantom without or with a 5-cm-thick fat-mimicking ring (widths, 30 and 40 cm) containing liver inserts with four spherical lesions was scanned with five exposure settings on each of two computed tomography scanners, one equipped with a DC detector and the other with an IC detector. Images from the DC and IC detector scanners were reconstructed with FBP and IR, respectively. Image noise and lesion CNR were measured. Four radiologists evaluated lesion presence on a five-point diagnostic confidence scale. Data analyses included receiver operating characteristic (ROC) curve analysis and noninferiority analysis. Results The combination of IC and IR significantly reduced image noise (P < .001) (with the greatest reduction in the 40-cm phantom and at lower exposures) and improved lesion CNR (P < .001). There was no significant difference in area under the ROC curve between detector-reconstruction combinations at fixed exposure for either phantom. Reader accuracy with IC-IR was noninferior at 50% (100 mAs [effective]) and 25% (300 mAs [effective]) exposure reduction for the 30- and 40-cm phantoms, respectively (adjusted P < .001 and .04 respectively). IC-IR improved readers' confidence in the presence of a lesion (P = .029) independent of phantom size or exposure level. Conclusion IC-IR improved objective image quality and lesion detection confidence but did not result in superior diagnostic accuracy when compared with DC-FBP. Moderate exposure reductions maintained comparable diagnostic accuracy for both detector-reconstruction combinations. Lesion detection in the 40-cm phantom was inferior at smaller exposure reduction than in the 30-cm phantom. (©) RSNA, 2016 Online supplemental material is available for this article.
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Artefactos , Hígado/diagnóstico por imagen , Tomografía Computarizada Multidetector/métodos , Fantasmas de Imagen , Exposición a la Radiación/estadística & datos numéricos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Humanos , Tomografía Computarizada Multidetector/estadística & datos numéricos , Dosis de Radiación , Relación Señal-RuidoRESUMEN
OBJECTIVE: The purpose of this study was to compare iterative metal artifact reduction (iMAR), a new single-energy metal artifact reduction technique, with filtered back projection (FBP) in terms of attenuation values, qualitative image quality, and streak artifacts near shoulder and hip arthroplasties and observer ability with these techniques to detect pathologic lesions near an arthroplasty in a phantom model. MATERIALS AND METHODS: Preoperative and postoperative CT scans of 40 shoulder and 21 hip arthroplasties were reviewed. All postoperative scans were obtained using the same technique (140 kVp, 300 quality reference mAs, 128 × 0.6 mm detector collimation) on one of three CT scanners and reconstructed with FBP and iMAR. The attenuation differences in bones and soft tissues between preoperative and postoperative scans at the same location were compared; image quality and streak artifact for both reconstructions were qualitatively graded by two blinded readers. Observer ability and confidence to detect lesions near an arthroplasty in a phantom model were graded. RESULTS: For both readers, iMAR had more accurate attenuation values (p < 0.001), qualitatively better image quality (p < 0.001), and less streak artifact (p < 0.001) in all locations near arthroplasties compared with FBP. Both readers detected more lesions (p ≤ 0.04) with higher confidence (p ≤ 0.01) with iMAR than with FBP in the phantom model. CONCLUSION: The iMAR technique provided more accurate attenuation values, better image quality, and less streak artifact near hip and shoulder arthroplasties than FBP; iMAR also increased observer ability and confidence to detect pathologic lesions near arthroplasties in a phantom model.
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Artroplastia de Reemplazo de Cadera , Artroplastía de Reemplazo de Hombro , Prótesis de Cadera , Prótesis de Hombro , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Artefactos , Femenino , Humanos , Masculino , Metales , Persona de Mediana Edad , Fantasmas de Imagen , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios RetrospectivosRESUMEN
Modern fluoroscopes used for image-based guidance in interventional procedures are complex X-ray machines, with advanced image acquisition and processing systems capable of automatically controlling numerous parameters based on defined protocol settings. This study evaluated and compared approaches to technique factor modulation and air kerma rates in response to simulated patient thickness variations for four state-of-the-art and one previous-generation interventional fluoroscopes. A polymethyl methacrylate (PMMA) phantom was used as a tissue surrogate for the purposes of determining fluoroscopic reference plane air kerma rates, kVp, mA, and variable copper filter thickness over a wide range of simulated tissue thicknesses. Data were acquired for each fluoroscopic and acquisition dose curve within each vendor's default abdomen or body imaging protocol. The data obtained indicated vendor- and model-specific variations in the approach to technique factor modulation and reference plane air kerma rates across a range of tissue thicknesses. However, in the imaging protocol evaluated, all of the state-of-the-art systems had relatively low air kerma rates in the fluoroscopic low-dose imaging mode as compared to the previous-generation unit. Each of the newest-generation systems also employ Cu filtration within the selected protocol in the acquisition mode of imaging; this is a substantial benefit, reducing the skin entrance dose to the patient in the highest dose-rate mode of fluoroscope operation. Some vendors have also enhanced the radiation output capabilities of their fluoroscopes which, under specific conditions, may be beneficial; however, these increased output capabilities also have the potential to lead to unnecessarily high dose rates. Understanding how fluoroscopic technique factors are modulated provides insight into the vendor-specific image acquisition approach and may provide opportunities to optimize the imaging protocols for clinical practice.
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Fluoroscopía/métodos , Fantasmas de Imagen , Radiología Intervencionista , Humanos , Dosis de Radiación , Rayos XRESUMEN
The first goal of this study was to investigate the accuracy of the displayed reference plane air kerma (Ka,r) or air kerma-area product (Pk,a) over a broad spectrum of X-ray beam qualities on clinically used interventional fluoroscopes incorporating air kerma-area product meters (KAP meters) to measure X-ray output. The second goal was to investigate the accuracy of a correction coefficient (CC) determined at a single beam quality and applied to the measured Ka,r over a broad spectrum of beam qualities. Eleven state-of-the-art interventional fluoroscopes were evaluated, consisting of eight Siemens Artis zee and Artis Q systems and three Philips Allura FD systems. A separate calibrated 60 cc ionization chamber (external chamber) was used to determine the accuracy of the KAP meter over a broad range of clinically used beam qualities. For typical adult beam qualities, applying a single CC deter-mined at 100 kVp with copper (Cu) in the beam resulted in a deviation of < 5% due to beam quality variation. This result indicates that applying a CC determined using The American Association of Physicists in Medicine Task Group 190 protocol or a similar protocol provides very good accuracy as compared to the allowed ± 35% deviation of the KAP meter in this limited beam quality range. For interventional fluoroscopes dedicated to or routinely used to perform pediatric interventions, using a CC established with a low kVp (~ 55-60 kVp) and large amount of Cu filtration (~ 0.6-0.9 mm) may result in greater accuracy as compared to using the 100 kVp values. KAP meter responses indicate that fluoroscope vendors are likely normalizing or otherwise influencing the KAP meter output data. Although this may provide improved accuracy in some instances, there is the potential for large discrete errors to occur, and these errors may be difficult to identify.
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Calibración/normas , Fluoroscopía/normas , Mejoramiento de la Calidad/normas , Dosímetros de Radiación/normas , Equipos y Suministros de Radiación/normas , Adulto , Humanos , Rayos XRESUMEN
This study sought to obtain a better understanding of how clergy view their health and to investigate their self-reported health status. Additionally, this study sought to explore personal and professional barriers among clergy to living a healthier life. An electronic 32-item survey was sent to all practicing clergy in Kansas East and West conferences of United Methodist church by the Kansas Area Office of the United Methodist Church. Survey items included participants' demographic information and health conditions (e.g., diabetes, heart disease, high blood pressure, high cholesterol). The self-reported general health, mental health, and physical health data were also collected to compare to the general population in Kansas. Clergy were also asked to identify perceived barriers to health. A total of 150 clergy participated in the survey. The majority (93.7 %) self-reported their health as good, very good, or excellent. Participating clergy self-reported a higher prevalence of chronic diseases (diabetes, heart disease, high blood pressure, and high cholesterol) than the Kansas general population, but those differences were not statistically significant. More than three-fourths (77.4 %) of the participating clergy reported weights and heights that classified them as either overweight or obese. Lack of family time was the most frequently reported personal barrier to achieving a healthier lifestyle. An unpredictable work schedule was reported as the most frequent professional barrier to achieving a healthier lifestyle. This study suggests that Kansas clergy generally view their overall health status favorably despite being overweight or obese. Clergy also self-reported higher prevalence of chronic diseases than the general Kansas population, though the prevalence was not statistically different. This study provides additional insight into clergy health and offers suggestions to address the barriers preventing clergy from working toward better health.
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Actitud Frente a la Salud , Clero/psicología , Conductas Relacionadas con la Salud , Estado de Salud , Estilo de Vida , Adulto , Anciano , Anciano de 80 o más Años , Clero/estadística & datos numéricos , Estudios Transversales , Femenino , Humanos , Kansas , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVE: The purposes of this study were to determine the differences in estimated volumetric CT dose index (CTDIvol) obtained from the topogram before abdominal and pelvic MDCT in adult and pediatric patients using a scan type-based algorithm for selecting kilovoltage (CARE kV) and a fixed and a weight-based Quality Reference mAs for selecting tube (gmAs) current-exposure time product, in comparison with standard protocols, and to determine the bias and variability of estimated CTDIvol vis-à-vis actual CTDIvol using the standard protocols. MATERIALS AND METHODS: During a 14-month period, 312 adult and pediatric patients referred for abdominal and pelvic MDCT were included in the study. For all patients, the estimated CTDIvol based on the topogram was recorded: protocol A, CARE kV on and 210 gmAs; protocol B, CARE kV on and 1 gmAs times patient weight (in pounds); and protocol C (standard protocol), CARE kV off, 120 kVp, and 1 gmAs times patient weight (in pounds). For the pediatric patients, estimated CTDIvol for the standard protocol D was calculated with 120 kVp and 150 gmAs. All patients were scanned with the standard protocols, and the actual CTDIvol was recorded. Linear regression models compared the CTDIvol of the three protocols in adults and the fourth for children. The estimated and actual CTDIvol were compared using a t test. RESULTS: Protocol B yielded the lowest estimated CTDIvol (mean, 13.2 mGy for adults and 3.5 mGy for pediatric patients). The estimated CTDIvol overestimated the actual CTDIvol by, on average, 1.07 mGy for adults and 0.3 mGy for children. CONCLUSION: CARE kV appears to reduce estimated CTDIvol vis-à-vis standard protocols only when a weight-based gmAs is used. Prescan estimated CTDIvol calculations appear to generally overestimate actual CTDIvol.
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Tomografía Computarizada Multidetector/instrumentación , Dosis de Radiación , Adolescente , Adulto , Algoritmos , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Radiografía AbdominalRESUMEN
Smoking during pregnancy is associated with poor birth outcomes. The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) is a public nutritional assistance program for low-income pregnant women and their children up to age five. This study examined differences in smoking behavior among women enrolled in the Kansas WIC program. A secondary analysis was conducted using the Pregnancy Nutrition Surveillance System dataset of enrolled women between 2005 and 2011. Geographic residency status was obtained through application of the Census tract-based rural-urban commuting area codes. Chi square tests of association were used to assess differences. Multi-variable binary logistic regression was used to assess maternal characteristics and smoking 3 months prior to pregnancy. Total sample size averaged 21,650 women for years 2005 through 2011. Low-income, rural pregnant women smoked at significantly higher rates before, during, and after pregnancy. High smoking rates have remained unchanged since 2008. The following characteristics were associated with reduced odds of smoking 3 months prior to pregnancy: being 17 years old or younger, Hispanic, a high school graduate, urban location, normal body mass index, no live births prior to current pregnancy, and using multi-vitamins. Results from this study indicate that the WIC population in rural areas may have different needs regarding smoking cessation programming than the urban WIC population. Findings help inform WIC program administrators and assist in enhancing current smoking cessation services to the Kansas WIC population.
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Pobreza/estadística & datos numéricos , Asistencia Pública/estadística & datos numéricos , Características de la Residencia/estadística & datos numéricos , Fumar/epidemiología , Adolescente , Adulto , Factores de Edad , Femenino , Humanos , Kansas , Embarazo , Factores Socioeconómicos , Adulto JovenRESUMEN
CONTEXT: Community health assessment (CHA) and community health improvement planning (CHIP) are important functions for local health departments (LHDs) but may present challenges, particularly in rural settings. OBJECTIVE: The purpose of this 2-year, mixed-methods study was to identify factors that impede or promote the timeliness and quality of CHA-CHIP completion in Kansas. DESIGN: Focus group interviews, conducted at baseline (2012) and at 1 year (2013), included 15 and 21 groups, respectively. Scores from a 12-item attitudinal survey that explored participants' confidence to perform CHA-CHIP activities were collected in tandem with focus groups. SETTING: Kansas counties that planned to conduct a CHA-CHIP process during 2012 and/or 2013 were eligible to participate. PARTICIPANTS: There were 128 study participants (57 in 2012, 71 in 2013), who were predominantly female (83%), aged 51 years or older (61.4%), and lived in rural areas (84.6%). Public health region representation in 2012 and 2013 was 73% and 93%, respectively. MAIN OUTCOME MEASURES: Changes in perceptions about CHA-CHIP inputs, process, outputs, outcomes, and self-efficacy to perform CHA-CHIP activities were explored. RESULTS: Progress in CHA-CHIP implementation was reported in 2013. Most participants perceived the CHA-CHIP process as valuable and enhanced the LHD's visibility. Rural participants reported having completed the CHA phase, whereas urban LHDs had progressed into the planning and implementation stage. Potentiators of the CHA-CHIP process included (1) parallel assessment activities conducted by other community organizations, and (2) for rural counties, a functioning 501(c)3 community health coalition. Perceptions about the importance of partnership and leadership were unchanged. A multivariate regression analysis revealed a significant time effect and rural-urban difference in perceived self-efficacy. CONCLUSIONS: Workforce development and public health system development issues are central concerns identified by this study. Local health departments with constrained resources and limited staff, despite additional training, are unlikely to develop the capacity needed to effectively support CHA-CHIP, making long-term sustainability uncertain.
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Planificación en Salud Comunitaria/métodos , Gobierno Local , Administración en Salud Pública/normas , Garantía de la Calidad de Atención de Salud , Grupos Focales , Humanos , Kansas , Administración en Salud Pública/tendenciasRESUMEN
PURPOSE: To measure the effect of reduced radiation exposure on low-contrast low-attenuation liver lesion detection in an anthropomorphic abdominal phantom by using filtered back projection (FBP) and sinogram-affirmed iterative reconstruction. MATERIALS AND METHODS: Eighteen radiologists blinded to phantom and study design interpreted randomized image data sets that contained 36 spherical simulated liver lesions of three sizes and three attenuation differences (5-mm diameter: 12, 18, and 24 HU less than the 90-HU background attenuation of the simulated liver insert; 10- and 15-mm diameter: 6, 12, and 18 HU less than the 90-HU background attenuation) scanned with four discrete exposure settings and reconstructed by using FBP and sinogram-affirmed iterative reconstruction. Response assessment included region-level lesion presence or absence on a five-point diagnostic confidence scale. Statistical evaluation included multireader multicase receiver operating characteristic curve analysis, with nonparametric methods and noninferiority analysis at a margin of -0.10. RESULTS: Pooled accuracy at 75% exposure for both FBP and sinogram-affirmed iterative reconstruction was noninferior to 100% exposure (P = .002 and P < .001, respectively). Subsequent exposure reductions resulted in a significant decrease in accuracy. When the smallest (5-mm-diameter) lesions were excluded from analysis, sinogram-affirmed iterative reconstruction was superior to FBP at 100% exposure (P = .011), and sinogram-affirmed iterative reconstruction at 25% and 50% exposure reduction was noninferior to FBP at 100% exposure (P ≤ .013). Reader confidence was greater with sinogram-affirmed iterative reconstruction than with FBP for 10- and 15-mm lesions (2.94 vs 2.76 and 3.62 vs 3.52, respectively). CONCLUSION: In this low-contrast low-attenuation liver lesion model, a 25% exposure reduction maintained noninferior diagnostic accuracy. However, detection was inferior with each subsequent exposure reduction, regardless of reconstruction method. Sinogram-affirmed iterative reconstruction and FBP performed equally well at modest exposure reduction (25%-50%). Readers had higher confidence levels with sinogram-affirmed iterative reconstruction for the 10- and 15-mm lesions.
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Hepatopatías/diagnóstico por imagen , Fantasmas de Imagen , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador , Radiografía Abdominal/métodos , Tomografía Computarizada por Rayos X/métodos , Humanos , Programas InformáticosRESUMEN
PURPOSE: To compare images acquired with 50% tube exposure with a dual-source computed tomographic (CT) scanner and reconstructed with sinogram-affirmed iterative reconstruction (SAFIRE) with 100% exposure images reconstructed with filtered back projection (FBP) for reader ability to detect stones, reader confidence, and findings outside the urinary tract. MATERIALS AND METHODS: In this HIPAA-compliant, institutional review board-approved study, imaging examinations in 99 patients with urolithiasis were assessed. Data from both tubes were reconstructed with FBP; data from the primary tube only were reconstructed with SAFIRE. Seven readers evaluated randomized studies for calculi in nine regions. Reader confidence was scored by using a five-point scale. Ancillary findings were noted. Nonparametric methods for clustered data were used to estimate the area under the receiver operating characteristic curves with 95% confidence intervals to test for noninferiority of 50% exposure with SAFIRE. RESULTS: Calculi were found in 113 locations (pyelocalyceal ureter, 86; proximal ureter, seven; midureter, four; distal ureter, 15; bladder, one) and not found in 752 locations. Mean area under the receiver operating characteristic curve for FBP was 0.879 (range, 0.607-0.967) and for SAFIRE, 0.883 (range, 0.646-0.971; 95% confidence interval: -0.025, 0.031). The SAFIRE images were not significantly inferior to FBP images (P = .001). Reader confidence levels for images with stones were similar with FBP and SAFIRE (P = .963). For the 52 patients who had extraurinary findings, readers reported them correctly in 74.4% (271 of 364) and 72.0% (262 of 364) of cases (P = .215) for FBP and SAFIRE, respectively. For the nine patients with potentially important findings per the reference standard, the detection rates were 44% (28 of 63) and 33% (21 of 63, P = .024), respectively. For the 43 patients with unimportant or likely unimportant findings, the false detection rates were 15% (44 of 301) and 14% (43 of 301, P = .756), respectively. CONCLUSION: The 50% tube exposure CT images reconstructed with SAFIRE were not inferior to 100% exposure images reconstructed with FBP for diagnosis of urolithiasis, without decreases in reader confidence.
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Algoritmos , Almacenamiento y Recuperación de la Información/métodos , Protección Radiológica/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Urolitiasis/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosis de Radiación , Intensificación de Imagen Radiográfica/métodos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
OBJECTIVES: We examined the impact of geographic residency status and census tract (CT)-level socioeconomic status (SES) on colorectal cancer (CRC) outcomes. METHODS: This was a retrospective cohort study of patients diagnosed with CRC in Georgia for the years 2000 through 2007. Study outcomes were late-stage disease at diagnosis, receipt of treatment, and survival. RESULTS: For colon cancer, residents of lower-middle-SES and low-SES census tracts had decreased odds of receiving surgery. Rural, lower-middle-SES, and low-SES residents had decreased odds of receiving chemotherapy. For patients with rectal cancer, suburban residents had increased odds of receiving radiotherapy, but low SES resulted in decreased odds of surgery. For survival, rural residents experienced a partially adjusted 14% (hazard ratio [HR] = 1.14; 95% confidence interval [CI] = 1.07, 1.22) increased risk of death following diagnosis of CRC that was somewhat explained by treatment differences and completely explained by CT-level SES. Lower-middle- and low-SES participants had an adjusted increased risk of death following diagnosis for CRC (lower-middle: HR = 1.16; 95% CI = 1.10, 1.22; low: HR = 1.24; 95% CI = 1.16, 1.32). CONCLUSIONS: Future efforts should focus on developing interventions and policies that target rural residents and lower SES areas to eliminate disparities in CRC-related outcomes.
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Censos , Neoplasias Colorrectales , Evaluación de Procesos y Resultados en Atención de Salud , Características de la Residencia , Clase Social , Distribución por Edad , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/clasificación , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/terapia , Intervalos de Confianza , Femenino , Georgia/epidemiología , Política de Salud , Accesibilidad a los Servicios de Salud , Humanos , Masculino , Persona de Mediana Edad , Sistema de Registros , Estudios Retrospectivos , Población Rural/estadística & datos numéricos , Distribución por Sexo , Análisis de SupervivenciaRESUMEN
OBJECTIVE: Identify perceptions regarding benefits of and barriers to receiving text messages for immunization reminders and preferred content for such text messages. DESIGN: Structured interviews. SETTING: Outpatient pediatric resident and faculty clinic. PARTICIPANTS: A convenience sample of 54 low-income urban Latino parents of children aged < or = 2 years. MAIN OUTCOME MEASURES: Parent perspectives on text message reminders. RESULTS: Most respondents were female (70%), married (63%), and fluent only in Spanish (89%). Most (83%) had a health literacy score in the adequate range. All (100%) reported being interested in receiving immunization reminders by text message, and 81% reported being willing to receive general appointment reminders by text message. Parents made 72 comments regarding benefits of text message immunization reminders. The most common sub-category was usefulness of the reminders (53%). These comments reflected participants' busy schedules and the beneficial nature of text messages in reminding parents of appointments. Fifty-six comments were provided regarding barriers to receiving text message reminders. Most comments (77%) indicated no identifiable barriers. Twenty percent described barriers related to technology, such as costs or lack of text messaging service. Parents generated 108 comments regarding preferred content of reminders. The topics most frequently identified were appointment date and time (32%), names of the vaccines (19%), and the child's name (11%). CONCLUSIONS: Low-income Latino parents perceive text message immunization reminders as a feasible alternative to more traditional forms of communication.
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Hispánicos o Latinos/psicología , Esquemas de Inmunización , Padres/psicología , Sistemas Recordatorios , Envío de Mensajes de Texto , Adulto , Atención a la Salud , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Programas de Inmunización , Masculino , Pobreza , Población Urbana , Adulto JovenRESUMEN
In 2013, we administered a 15-item survey to determine the extent of text message usage among Latino adults in Kansas; for a subset of the survey participants, we also conducted a 6-week pilot trial to determine the effect of text messaging on exercise behaviors. Among the 82 survey participants, 78% had unlimited text messaging. At baseline, all trial participants were at the stage of contemplation; at 6 weeks, one (9%) trial participant remained at the contemplation stage and the other 10 (91%) participants progressed to the action/maintenance/termination stage. Use of text messaging to motivate exercise is feasible and potentially efficacious among Latinos.
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Aterosclerosis/prevención & control , Hispánicos o Latinos , Actividad Motora , Enfermedades Vasculares Periféricas/prevención & control , Envío de Mensajes de Texto , Recolección de Datos , Femenino , Humanos , Kansas/epidemiología , Masculino , Persona de Mediana Edad , Enfermedades Vasculares Periféricas/epidemiología , Enfermedades Vasculares Periféricas/etnología , Proyectos Piloto , Factores SocioeconómicosRESUMEN
OBJECTIVE: The purpose of this article is to determine the decrease in volume CT dose index (CTDI(vol)) and dose-length product (DLP) achieved by switching from fixed quality reference tube current protocols with automatic tube current modulation to protocols adjusting the quality reference tube current, slice collimation, and peak kilovoltage according to patient weight. MATERIALS AND METHODS: All adult patients who underwent CT examinations of the abdomen or abdomen and pelvis during 2010 using weight-based protocols who also underwent a CT examination in 2008 or 2009 using fixed quality reference tube current protocols were identified from the radiology information system. Protocol pages were electronically retrieved, and the CT model, examination date, scan protocol, CTDI(vol), and DLP were extracted from the DICOM header or by optical character recognition. There were 15,779 scans with dose records for 2700 patients. Changes in CTDI(vol) and DLP were compared only between examinations of the same patient and same CT system model for examinations performed in 2008 or 2009 and those performed in 2010. The final analysis consisted of 1117 comparisons in 1057 patients, and 1209 comparisons in 988 patients for CTDI(vol) and DLP, respectively. RESULTS: The change to a weight-based protocol resulted in a statistically significant reduction in CTDI(vol) and DLP on three MDCT system models (p < 0.001). The largest average CTDI(vol) decrease was 13.9%, and the largest average DLP decrease was 16.1% on a 64-MDCT system. Both the CTDI(vol) and DLP decreased the most for patients who weighed less than 250 lb (112.5 kg). CONCLUSION: Adjusting the CT protocol by selecting parameters according to patient weight is a viable method for reducing CT radiation dose. The largest reductions occurred in the patients weighing less than 250 lb.
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Peso Corporal , Tomografía Computarizada Multidetector/métodos , Dosis de Radiación , Protección Radiológica/métodos , Radiografía Abdominal/métodos , Adulto , Protocolos Clínicos , Femenino , Humanos , Modelos Lineales , Masculino , Tomografía Computarizada Multidetector/instrumentación , Selección de Paciente , Radiografía Abdominal/instrumentación , Estudios RetrospectivosRESUMEN
OBJECTIVE: The study objective was to determine the prevalence of diabetes and prediabetes among rural and urban populations in Kansas. RESEARCH DESIGN AND METHODS: This study utilized 2009 BRFSS data and included 18,912 respondents. Participants were identified through a stratified random sample of adult Kansans, living in a non-institutionalized setting, and with access to a land-based telephone line. Analyses were conducted using SAS to provide descriptive statistics for groups based on diabetes status. A logistic regression was conducted to explore significant variables associated with the likelihood of diabetes. RESULTS: Diabetes prevalence was lower among urban (11.8%) populations than rural (12.7%) areas of Kansas, but the inverse was true for pre-diabetes (3.7% urban, 3.1% in rural). Lower income and lower levels of educational attainment were associated with increased rates of diabetes and pre-diabetes, with the highest prevalence levels overall found among rural Latinos (19.3%) and urban African Americans (22.9%). Multivariate regression suggests that age, income, ethnicity, education, sex, rural vs urban status, and race all served as significant predicators of diabetes, net of other factors. CONCLUSIONS: Rural residents were more likely than urban residents to report having diabetes, whereas urban residents were more likely than rural residents to report having pre-diabetes. Although rural vs urban status played a significant role in the model's predicative ability for diabetes and pre-diabetes diagnosis, increased age was by far the most significant factor in diabetes and pre-diabetes diagnosis.
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Diabetes Mellitus Tipo 2/epidemiología , Estado Prediabético/epidemiología , Adolescente , Adulto , Anciano , Diabetes Mellitus Tipo 2/etnología , Escolaridad , Femenino , Humanos , Kansas/epidemiología , Masculino , Persona de Mediana Edad , Estado Prediabético/etnología , Prevalencia , Factores de Riesgo , Población Rural , Factores Socioeconómicos , Población UrbanaRESUMEN
BACKGROUND: To investigate the impact of radiation exposure from a computed tomography (CT) scanner on the functional integrity of a wearable insulin delivery system. METHODS: A total of 160 Omnipods and four personal diabetes managers (PDMs) were evenly divided into four groups: (1) control group (no radiation exposure), (2) typical radiation exposure group, (3) 4× typical radiation exposure group, and (4) scatter radiation group. Pods were attached to an anthropomorphic torso phantom on the abdomen (direct irradiation) or shoulder (scatter radiation) region. A third-generation dual-source CT scanner was used to scan the pods using either a typical exposure (used for routine CT abdominal study of a median size patient) or 4× typical exposure. A manufacturer-recommended 20-step functionality test was performed for all 160 Omnipods. RESULTS: The radiation dose (measured in volume CT Dose index) was 16 mGy for a typical exposure, and 64 mGy for 4× typical exposure. The scatter radiation is less than 0.1 mGy. All Pods passed the functionality test except one pod in the scatter radiation group, which sounded an alarm due to occlusion. The blockage to the fluid was due to a kink in the soft cannula, a mechanical issue not caused by the radiation exposure. CONCLUSIONS: This study suggests X-ray exposure levels used in radiological imaging procedures do not negatively impact the functional integrity of Omnipods. This finding may support the potential for the manufacturer to remove the warning that patients should remove the Pod for X-ray imaging procedures, which will have a huge impact on patient care.