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OBJECTIVES: Based on a narrative review of the literature to 1) assess the need for and 2) report methods to help deliver a sustainable approach to iodinated contrast media (ICM) administration. KEY FINDINGS: Acute ICM shortages have been noted in the literature. As demand for contrast-enhanced imaging continues to increase and access to raw materials becomes more limited, such events may increase. Evidence from the literature has documented a range of iodinated contrast reduction strategies. These include individualised contrast-media dosing, multi-dose bulk ICM vials, switching to alternative modalities or the increased use of non-contrast examinations. The optimisation of imaging parameters, the use of saline chasers, and alternative contrast agents should be further considered. Given the rising concerns regarding the presence and effects of ICMs in waste and drinking water, further consideration of strategies for managing waste and excreted ICMs are starting to emerge. CONCLUSIONS: Sustainable ICM practices are needed to help avoid supply shortages and to help protect our environment. Such practices must be led and supported locally, nationally, and internationally. Sustainable ICM practices must be reflected within professional Standards of Proficiencies and be adopted by all members of the multidisciplinary team. IMPLICATIONS FOR PRACTICE: Changes to working practices surrounding the sustainable use of ICMs will likely become commonplace. New methods to ensure optimised ICM dosage with minimal wastage will be more heavily featured in departmental practices. Correct disposal of waste and excreted ICMs will also form part of future changes to practice.
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This paper reports conclusions from a recent study completed for the Water Research Foundation and the State of California to offer guidance on UV-chlorine advanced oxidation for potable water reuse. The fundamentals of UV-chlorine advanced oxidation are discussed, and lessons learned from some of the early adopters of this technology are presented. Important highlights include the significant impact of ammonia and chloramines on UV-chlorine treatment, challenges associated with predicting UV-chlorine performance due to complex photochemistry, and an ongoing need to monitor potential byproducts and transformation products when employing any form of advanced oxidation for potable reuse.
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INTRODUCTION: As weights among neonates can vary from <900 g to >2.5 kg, weight-based Diagnostic Reference Levels (DRLs) specific to the neonatal intensive care unit (NICU) are essential. Repeated radiation exposure to this sensitive patient group raises concerns regarding high cumulative radiation doses and the potential for long-term health detriment. This study aimed to establish weight-based DRLs for neonates undergoing mobile chest radiography (CXR) in the NICU. METHODS: Neonates were classified into three discrete groups; <1000, 1000-2500 and >2500 g. Data were collected prospectively over three months; 95 DAP values were collected, and five were excluded due to poor technique, leaving 90 patients that met the inclusion criteria for mobile CXR in the NICU. Dose-area-product (DAP) in mGycm2, the peak kilovoltage (kVp) and the product of tube current and exposure time (mAs) were retrieved from the Picture Archiving and Communication System (PACS). Images and radiological reports were also analysed to confirm diagnostic image quality (IQ). Local DRLs (LDRLs) were derived using the median DAP, and national DRLs were suggested using the 3rd quartile value. RESULTS: The proposed LDRLs for neonates weighing <1000 g was 2.7 mGycm2, for neonates weighing between 1000 g and 2500 g, it was 3.7 mGycm2, and for neonates weighing >2500 g it was 6.6 mGycm2. The radiation dose received by the 90 (100%) neonates included in the study fell below 11.4 mGycm2; of these, 82% of the DAP values fell below the study institution's existing LDRL of 7.25 mGycm2. CONCLUSION: Weight-based DRLs provide crucial information on doses to this specific radiation-sensitive group. This work recommends using weight-based categories for DRLs and serves as a benchmark for neonatal CXR standardisation and optimisation. IMPLICATIONS FOR PRACTICE: The proposed weight-based DRLs can be adopted for neonates' locally, nationally and internationally.
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Niveles de Referencia para Diagnóstico , Recién Nacido , Humanos , Dosis de Radiación , Rayos X , Radiografía , Estándares de ReferenciaRESUMEN
AIM: To evaluate the use of computed tomography (CT) and low-dose CT in the detection of latent tuberculosis (TB). MATERIALS AND METHODS: A systematic search of literature in adherence with the PRISMA guidelines was carried out. Quality assessment of the included studies was conducted. RESULTS: The search strategy identified a total of 4,621 studies. Sixteen studies were considered eligible and included in the review. There was high heterogeneity among all studies. CT was identified as much more sensitive for the detection of latent TB in all studies despite chest radiography often being recommended in guidelines to assess patients for latent TB. Low-dose CT showed promising results in four of the studies; however, these results were limited due to small sample sizes. CONCLUSION: CT is much superior to chest radiography consistently identifying additional cases of latent TB. There are limited high-quality publications available using low-dose CT but findings thus far suggest low-dose CT could be used as an alternative to standard-dose CT for the detection of latent TB. It is recommended that a randomised controlled trial investigating low-dose CT should be carried out.
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Tuberculosis Latente , Humanos , Tuberculosis Latente/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodosRESUMEN
The Z machine is a current driver producing up to 30 MA in 100 ns that utilizes a wide range of diagnostics to assess accelerator performance and target behavior conduct experiments that use the Z target as a source of radiation or high pressures. We review the existing suite of diagnostic systems, including their locations and primary configurations. The diagnostics are grouped in the following categories: pulsed power diagnostics, x-ray power and energy, x-ray spectroscopy, x-ray imaging (including backlighting, power flow, and velocimetry), and nuclear detectors (including neutron activation). We will also briefly summarize the primary imaging detectors we use at Z: image plates, x-ray and visible film, microchannel plates, and the ultrafast x-ray imager. The Z shot produces a harsh environment that interferes with diagnostic operation and data retrieval. We term these detrimental processes "threats" of which only partial quantifications and precise sources are known. We summarize the threats and describe techniques utilized in many of the systems to reduce noise and backgrounds.
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INTRODUCTION: Dementia is a syndrome associated with a decline in brain function, impacting how we speak, think, feel, and behave. Misunderstanding of dementia and how it affects patients and their carers is common. There is limited research on how radiographers provide adequate care to those with dementia. Radiographers with knowledge and positive attitudes can reduce stigma and fear, improving the quality of care. This study aimed to assess radiographers' knowledge and attitudes towards dementia. METHODS: A cohort of registered radiographers in Ireland participated in an online survey. Two pre-existing validated questionnaires: The Alzheimer's Disease Knowledge Scale (ADKS) and the Dementia Attitudes Scale (DAS), assessed radiographers' knowledge and attitudes towards dementia and people with dementia. Scores were compared across variables such as gender, age, grade, qualification, work setting, and the number of years qualified. RESULTS: A total of 123 radiographers responded. Knowledge scores did not significantly differ across demographic groups (p > 0.05). Total knowledge scores ranged from 60% to 100%. Total attitude scores ranged from 50% to 100%. Participants with a BSc, MSc, and other post-graduate degrees scored higher on the attitude scale than those with a diploma qualification (p = 0.027). Those with less than 20 years' experience scored higher than those with more. Knowledge had little correlation with attitude (r = 0.0522; p = 0.5667). CONCLUSION: Findings indicate variations in attitudes linked to age and experience, and some misconceptions can be observed across varying groups. Interventions to improve attitudes and raise awareness are needed. IMPLICATIONS FOR PRACTICE: There is a need for further research and education on dementia care in the imaging department. We have identified areas requiring further education.
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Técnicos Medios en Salud , Demencia , Humanos , Actitud del Personal de Salud , Encuestas y Cuestionarios , Conocimientos, Actitudes y Práctica en SaludRESUMEN
INTRODUCTION: Healthcare workers have been particularly impacted by the COVID-19 pandemic, as have those educating them, albeit differently. Several papers have identified a gendered difference in the impact of the pandemic. This study aims to determine impact of COVID-19 on the health and wellbeing of Medical Imaging and Radiation Therapy (MIRT) academics. METHODS: An electronic survey was designed in English on Qualtrics and distributed via email and online platforms to MIRT academics. Fifty-one questions were used; demographic (n = 9), work patterns (n = 11), general health (n = 8), mental health (n = 2), physical health (n = 10), and workload (n = 11). Overall, 46 were quantitative and five were qualitative 'open-ended' questions. The survey was open between 3rd March 2021 to 1st May 2021. Quantitative analysis was carried out using MS Excel v 16.61.1ss and SPSS v26. RESULTS: The survey reached 32 countries globally and 412 participants; 23.5% identified as men (n = 97) and 76.5% as women (n = 315). Women reported worse sleep quality than men and overwhelmingly felt they would not like to work remotely again if given a choice. A higher percentage of males, 73% versus 40.5% of females reported getting outdoors less. The CORE-10 validated questionnaire found that 10.3% of males (n = 42) and 2.7% of females (n = 11) experienced severe psychological distress the week immediately before the survey was conducted. CONCLUSION: While the study has identified some gender-related differences in the impact of COVID-19 on the mental and physical health of MIRT academics, both males and females have experienced significant deterioration in health and wellbeing due to the pandemic. IMPLICATION FOR PRACTICE: Developing mental health support for MIRT academics and defining optimum methods for raising awareness is recommended.
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COVID-19 , COVID-19/epidemiología , Femenino , Personal de Salud , Humanos , Masculino , Pandemias , Radiografía , Encuestas y CuestionariosRESUMEN
INTRODUCTION: Artificial intelligence (AI) is increasingly utilised in medical imaging systems and processes, and radiographers must embrace this advancement. This study aimed to investigate perceptions, knowledge, and expectations towards integrating AI into medical imaging amongst a sample of radiographers and determine the current state of AI education within the community. METHODS: A cross-sectional online quantitative study targeting radiographers based in Europe was conducted over ten weeks. Captured data included demographical information, participants' perceptions and understanding of AI, expectations of AI and AI-related educational backgrounds. Both descriptive and inferential statistical techniques were used to analyse the obtained data. RESULTS: A total of 96 valid responses were collected. Of these, 64% correctly identified the true definition of AI from a range of options, but fewer (37%) fully understood the difference between AI, machine learning and deep learning. The majority of participants (83%) agreed they were excited about the advancement of AI, though a level of apprehensiveness remained amongst 29%. A severe lack of education on AI was noted, with only 8% of participants having received AI teachings in their pre-registration qualification. CONCLUSION: Overall positive attitudes towards AI implementation were observed. The slight apprehension may stem from the lack of technical understanding of AI technologies and AI training within the community. Greater educational programs focusing on AI principles are required to help increase European radiography workforce engagement and involvement in AI technologies. IMPLICATIONS FOR PRACTICE: This study offers insight into the current perspectives of European based radiographers on AI in radiography to help facilitate the embracement of AI technology and convey the need for AI-focused education within the profession.
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Inteligencia Artificial , Conocimientos, Actitudes y Práctica en Salud , Estudios Transversales , Humanos , Motivación , RadiografíaRESUMEN
INTRODUCTION: Breast cancer is one of the most prevalent cancers in women, however Irish Traveller women have lower breast screening rates than that of the general population. This work aims to address the gap in knowledge of Irish Traveller womens' perceptions of breast screening and the perceived barriers and enablers to attendance. METHODS: This phenomenological qualitative study involves interviews with Irish Traveller women and Health Care Professionals and discusses the incentives and barriers to attending breast screening mammography in Ireland. The work investigated attitudes and decision making amongst the Irish Traveller women across breast screening and breast health. The research investigated the participants knowledge, experience and opinions about the topic of Irish Traveller womens' attendance at BreastCheck and breast health RESULTS: Influences that create barriers to breast screening for Irish Traveller women include inequality and family/community support, fear, literacy and education, embarrassment and the health care professional, stress and appointment suitability. Findings also demonstrate inadequate data and information is available in Ireland regarding Irish Traveller women attending breast screening. CONCLUSION: Irish Traveller women face several influences when it comes to attending breast screening. The existing Irish national breast screening programme provides a health promotion service however, it is impossible to assess poor attendance at screening without the presence of an ethnic identifier. It would be very beneficial for screening promotion to record the ethnicity of attendees for statistical progress. This would benefit Irish Traveller women by recording the progress of attendance in the breast screening programme and creating a need for awareness and education within the annual reports. IMPLICATIONS FOR PRACTICE: Creating awareness and educating Irish Traveller women about the breast screening programme may remove barriers and lead to improved attendance rates.
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Neoplasias de la Mama , Neoplasias de la Mama/diagnóstico por imagen , Detección Precoz del Cáncer , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Mamografía , Tamizaje MasivoRESUMEN
Riparian zone vegetation plays an integral role in freshwater ecology, notably by buffering water temperatures, and in providing habitat for the adult stages of many aquatic species. We measured the contribution that riparian vegetation makes to temperature buffering, and how this affects the freshwater fauna, specifically using changes in abundances of baetid may flies for the Luvuvhu River catchment in South Africa. Water temperatures were compared for shaded versus un-shaded sites, and thermal stress between seasons was estimated using a cumulative probability model for the most widespread mayfly species, Dabulamanzia media. It is concluded that thermal stress due to losses in riparian shading could be detected using mayfly abundances in a regular monitoring programme.
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Ephemeroptera , Ríos , Temperatura , Animales , Ecología , Monitoreo del Ambiente , Estaciones del Año , SudáfricaRESUMEN
Aims: To describe and compare the adherence to different direct oral anticoagulants (DOACs) in eight European databases representing six countries. Methods: Longitudinal drug utilization study of new users (≥18 years) of DOACs (dabigatran, rivaroxaban, apixaban) with a diagnosis of non-valvular atrial fibrillation (2008-2015). Adherence was examined by estimating persistence, switching, and discontinuation rates at 12 months. Primary non-adherence was estimated in BIFAP and SIDIAP databases. Results: The highest persistence rate was seen for apixaban in the CPRD database (81%) and the lowest for dabigatran in the Mondriaan database (22%). The switching rate for all DOACs ranged from 2.4 to 13.1% (Mondriaan and EGB databases, respectively). Dabigatran had the highest switching rate from 5.0 to 20.0% (Mondriaan and EGB databases, respectively). The discontinuation rate for all DOACs ranged from 16.0 to 63.9% (CPRD and Bavarian CD databases, respectively). Dabigatran had the highest rate of discontinuers, except in the Bavarian CD and AOK NORDWEST databases, ranging from 23.2 to 64.6% (CPRD and Mondriaan databases, respectively). Combined primary non-adherence for examined DOACs was 11.1% in BIFAP and 14.0% in SIDIAP. There were differences in population coverage and in the type of drug data source among the databases. Conclusion: Despite the differences in the characteristics of the databases and in demographic and baseline characteristics of the included population that could explain some of the observed discrepancies, we can observe a similar pattern throughout the databases. Apixaban was the DOAC with the highest persistence. Dabigatran had the highest proportion of discontinuers and switchers at 12 months in most databases (EMA/2015/27/PH).
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AIM: To assess the utility of a volumetric low-dose computed tomography (CT) thorax (LDCTT) protocol at a dose equivalent to a posteroanterior (PA) and lateral chest radiograph for surveillance of cystic fibrosis (CF) patients. MATERIALS AND METHODS: A prospective study was undertaken of 19 adult patients with CF that proceeded to LDCTT at 12 and 24 months following initiation of ivacaftor. A previously validated seven-section, low-dose axial CT protocol was used for the 12-month study. A volumetric LDCTT protocol was developed for the 24-month study and reconstructed with hybrid iterative reconstruction (LD-ASIR) and pure iterative reconstruction (model-based IR [LD-MBIR]). Radiation dose was recorded for each scan. Image quality was assessed quantitatively and qualitatively, and disease severity was assessed using a modified Bhalla score. Statistical analysis was performed and p-values of <0.05 were considered statistically significant. RESULTS: Volumetric LD-MBIR studies were acquired at a lower radiation dose than the seven-section studies (0.08 ± 0.01 versus 0.10 ± 0.02 mSv; p=0.02). LD-MBIR and seven-section ASIR images had significantly lower levels of image noise compared with LD-ASIR images (p<0.0001). Diagnostic acceptability scores and depiction of bronchovascular structures were found to be acceptable for axial and coronal LD-MBIR images. LD-MBIR images were superior to LD-ASIR images for all qualitative parameters assessed (p<0.0001). No significant change was observed in mean Bhalla score between 1-year and 2-year studies (p=0.84). CONCLUSIONS: The use of a volumetric LDCTT protocol (reconstructed with pure IR) enabled acquisition of diagnostic quality CT images, which were considered extremely useful for surveillance of CF patients, at a dose equivalent to a PA and lateral chest radiograph.
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Regulador de Conductancia de Transmembrana de Fibrosis Quística/uso terapéutico , Fibrosis Quística/diagnóstico por imagen , Fibrosis Quística/tratamiento farmacológico , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Radiografía Torácica/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Estudios de Factibilidad , Femenino , Humanos , Masculino , Estudios Prospectivos , Dosis de Radiación , Adulto JovenRESUMEN
INTRODUCTION: This study investigates instances of elevated radiation dose on a radiation tracking system to determine their aetiologies. It aimed to investigate the impact of radiographer feedback on these alerts. METHODS: Over two six-month periods 11,298 CT examinations were assessed using DoseWatch. Red alerts (dose length products twice the median) were identified and two independent reviewers established whether alerts were true (unjustifiable) or false (justifiable). During the second time period radiographers used a feedback tool to state the cause of the alert. A Chi-Square test was used to assess whether red alert incidence decreased following the implementation of radiographer feedback. RESULTS: There were 206 and 357 alerts during the first and second time periods, respectively. These occurred commonly with CT pulmonary angiography, brain, and body examinations. Procedural documentation errors and patient size accounted for 57% and 43% of false alerts, respectively. Radiographer feedback was provided for 17% of studies; this was not associated with a significant change in the number of alerts, but the number of true alerts declined (from 7 to 3) (χ2 = 4.14; p = 0.04). CONCLUSION: Procedural documentation errors as well as patient-related factors are associated with false alerts in DoseWatch. Implementation of a radiographer feedback tool reduced true alerts. IMPLICATIONS FOR PRACTICE: The implementation of a radiographer feedback tool reduced the rate of true dose alerts. Low uptake with dose alert systems is an issue; the workflow needs to be considered to address this.
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Sistemas de Entrada de Órdenes Médicas , Documentación , Retroalimentación , Humanos , Dosis de Radiación , Tomografía Computarizada por Rayos XRESUMEN
Various reports of disease-related lung pathologies in common variable immunodeficiency disorder (CVID) patients have been published, with differing histological and high-resolution computed tomography (HRCT) findings. Data were extracted from the validated Oxford Primary Immune Deficiencies Database (PID) database (1986-2016) on adult, sporadic CVID patients with suspected interstitial lung disease (ILD). Histology of lung biopsies was studied in relation to length of follow-up, clinical outcomes, HRCT findings and chest symptoms, to look for evidence for different pathological processes. Twenty-nine CVID patients with lung histology and/or radiological evidence of ILD were followed. After exclusions, lung biopsies from 16 patients were reanalysed for ILD. There were no well-formed granulomata, even though 10 patients had systemic, biopsy-proven granulomata in other organs. Lymphocytic infiltration without recognizable histological pattern was the most common finding, usually with another feature. On immunochemistry (n = 5), lymphocytic infiltration was due to T cells (CD4 or CD8). Only one patient showed B cell follicles with germinal centres. Interstitial inflammation was common; only four of 11 such biopsies also showed interstitial fibrosis. Outcomes were variable and not related to histology, suggesting possible different pathologies. The frequent nodules on HRCT were not correlated with histology, as there were no well-formed granulomata. Five patients were asymptomatic, so it is essential for all patients to undergo HRCT, and to biopsy if abnormal HRCT findings are seen. Internationally standardized pathology and immunochemical data are needed for longitudinal studies to determine the precise pathologies and prognoses in this severe complication of CVIDs, so that appropriate therapies may be found.
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Linfocitos B/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Inmunodeficiencia Variable Común/inmunología , Bases de Datos Factuales , Enfermedades Pulmonares Intersticiales/inmunología , Pulmón/inmunología , Adolescente , Adulto , Linfocitos B/patología , Biopsia , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/patología , Niño , Inmunodeficiencia Variable Común/patología , Femenino , Estudios de Seguimiento , Granuloma del Sistema Respiratorio/inmunología , Granuloma del Sistema Respiratorio/patología , Humanos , Pulmón/patología , Enfermedades Pulmonares Intersticiales/patología , Masculino , Persona de Mediana Edad , Fibrosis Pulmonar/inmunología , Fibrosis Pulmonar/patologíaRESUMEN
Microfluidic acoustophoresis is a label-free technique that isolates a purified product from a complex mixture of cells. This technique is well-studied but thus far has lacked the throughput and device manufacturability needed for many medical and industrial uses. Scale-up of acoustofluidic devices can be more challenging than in other microfluidic systems because the channel walls are integral to the resonant behavior and coupling to neighboring channels can inhibit performance. Additionally, the increased device area needed for parallel channels becomes less practical in the silicon or glass materials usually used for acoustofluidic devices. Here, we report an acoustic separator with 12 parallel channels made entirely from polystyrene that achieves blood cell separation at a flow rate greater than 1 ml/min. We discuss the design and optimization of the device and the electrical drive parameters and compare the separation performance using channels of two different designs. To demonstrate the utility of the device, we test its ability to purify lymphocytes from apheresis product, a process that is critical to new immunotherapies used to treat blood cancers. We process a leukapheresis sample with a volume greater than 100 ml in less than 2 h in a single pass without interruption, achieving greater than 90% purity of lymphocytes, without any prepurification steps. These advances suggest that acoustophoresis could in the future aid in cell therapy bioprocessing and that further scale-up is possible.
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INTRODUCTION: Optimization of image quality and patient radiation dose is achieved in part by positioning the patient at the isocenter of the CT gantry. The aim of this study was to establish whether there was increased isocenter misalignment (IM) in CT colonography (CTC) scans by comparing patient position during the prone part of a CTC to patient position during renal stone protocol CT (CT-KUB) and patient position during the supine part of a CTC to patient position during abdominopelvic CT (CT-AP). METHODS: Two hundred and twenty two consecutive outpatient adult CTC studies performed between January and December 2016 were retrospectively analyzed. Automated dose-tracking software was used to quantify IM in the x and y planes. Renal stone CT-KUB (n = 100) and standard CT-AP (n = 100) were used as comparison studies. RESULTS: IM during CTC was significantly greater in the y-axis compared with the x-axis for both prone (p = 0.002) and supine (p < 0.001) scanning. IM was significantly greater during prone CTC compared with CT-KUB (p = 0.008) and during supine CTC compared with CT-AP (p = 0.0001). IM was shown to be slightly greater in studies performed by more experienced radiographers (p = 0.04). IM was not associated with patient age, gender or size (p > 0.05 for all). CONCLUSION: Isocenter misalignment is greater during CT colonography compared with CT-KUB or CT-AP. Strategies for improving patient positioning could include radiographer education and automated patient centering solutions.
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Colonografía Tomográfica Computarizada/métodos , Posicionamiento del Paciente/métodos , Adulto , Anciano , Anciano de 80 o más Años , Colon/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
INTRODUCTION: The aim of this study was to assess and compare the effects of CT image reconstruction techniques on low-dose CT image quality using phantoms. METHODS: Anthropomorphic torso and spatial/contrast-resolution phantoms were scanned at decreasing tube currents between 400 and 10 mA. CT thorax and abdomen/pelvis series were reconstructed with filtered back projection (FBP) alone, combined 40% adaptive statistical iterative reconstruction & FBP (ASIR40), and model-based iterative reconstruction (MBIR) [(resolution-preference 05 (RP05) and RP20 in the thorax and RP05 and noise-reduction 05 (NR05) in the abdomen)]. Two readers rated image quality quantitatively and qualitatively. RESULTS: In thoracic CT, objective image noise on MBIR RP05 data sets outperformed FBP at 200, 100, 50 and 10 mA and outperformed ASIR40 at 50 and 10 mA (p < 0.001). MBIR RP20 outperformed FBP at 50 and 10 mA and outperformed ASIR40 at 10 mA (p < 0.001). Compared with both FBP and ASIR40, MBIR RP05 demonstrated significantly better signal-to-noise ratio (SNR) at 10 mA. In abdomino-pelvic CT, MBIR RP05 and NR05 outperformed FBP and ASIR at all tube current levels for objective image noise. NR05 demonstrated greater SNR at 200, 100, 50 and 10 mA and RP05 demonstrated greater SNR at 50 and 10 mA compared with both FBP and ASIR. MBIR images demonstrated better subjective image quality scores. Spatial resolution, low-contrast detectability and contrast-to-noise ratio (CNR) were comparable between image reconstruction techniques. CONCLUSION: CTs reconstructed with MBIR have lower image noise and improved image quality compared with FBP and ASIR. These effects increase with reduced radiation exposure confirming optimal use for low-dose CT imaging.
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Radiografía Abdominal/métodos , Radiografía Torácica/métodos , Tomografía Computarizada por Rayos X/métodos , Humanos , Fantasmas de Imagen , Dosis de Radiación , Radiografía Abdominal/instrumentación , Radiografía Torácica/instrumentación , Relación Señal-Ruido , Tomografía Computarizada por Rayos X/instrumentaciónRESUMEN
Following the publication of this article [1], the authors informed us of the following error.
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Recapitulation of the tumor microenvironment is critical for probing mechanisms involved in cancer, and for evaluating the tumor-killing potential of chemotherapeutic agents, targeted therapies and immunotherapies. Microfluidic devices have emerged as valuable tools for both mechanistic studies and for preclinical evaluation of therapeutic agents, due to their ability to precisely control drug concentrations and gradients of oxygen and other species in a scalable and potentially high throughput manner. Most existing in vitro microfluidic cancer models are comprised of cultured cancer cells embedded in a physiologically relevant matrix, collocated with vascular-like structures. However, the recent emergence of immune checkpoint inhibitors (ICI) as a powerful therapeutic modality against many cancers has created a need for preclinical in vitro models that accommodate interactions between tumors and immune cells, particularly for assessment of unprocessed tumor fragments harvested directly from patient biopsies. Here we report on a microfluidic model, termed EVIDENT (ex vivo immuno-oncology dynamic environment for tumor biopsies), that accommodates up to 12 separate tumor biopsy fragments interacting with flowing tumor-infiltrating lymphocytes (TILs) in a dynamic microenvironment. Flow control is achieved with a single pump in a simple and scalable configuration, and the entire system is constructed using low-sorption materials, addressing two principal concerns with existing microfluidic cancer models. The system sustains tumor fragments for multiple days, and permits real-time, high-resolution imaging of the interaction between autologous TILs and tumor fragments, enabling mapping of TIL-mediated tumor killing and testing of various ICI treatments versus tumor response. Custom image analytic algorithms based on machine learning reported here provide automated and quantitative assessment of experimental results. Initial studies indicate that the system is capable of quantifying temporal levels of TIL infiltration and tumor death, and that the EVIDENT model mimics the known in vivo tumor response to anti-PD-1 ICI treatment of flowing TILs relative to isotype control treatments for syngeneic mouse MC38 tumors.
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Técnicas Analíticas Microfluídicas/instrumentación , Modelos Biológicos , Microambiente Tumoral/inmunología , Animales , Carcinoma de Pulmón de Células no Pequeñas/química , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Células Cultivadas , Diseño de Equipo , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Neoplasias Pulmonares/química , Neoplasias Pulmonares/inmunología , Linfocitos/citología , Linfocitos/metabolismo , Ratones , Técnicas Analíticas Microfluídicas/métodosRESUMEN
The pathology of migraine, a common neurological disease, involves sensitization and activation of trigeminal nociceptive neurons to promote hyperalgesia and allodynia during an attack. Migraineurs often exhibit characteristics of a hyperexcitable or hypervigilant nervous system. One of the primary reported risk factors for development of a hyperexcitable trigeminal system is chronic, unmanaged stress and anxiety. While primary traumatic stress is a commonly cited risk factor for many pain conditions, exposure to secondary traumatic stress early in life is also thought to be a contributing risk factor. The goal of this study was to investigate cellular changes within the spinal trigeminal nucleus and trigeminal ganglion mediated by secondary traumatic stress. Male Sprague Dawley rats (sender) were subjected to forced swim testing (primary traumatic stress) and were then housed in close visual, olfactory, and auditory proximity to the breeding male and female rats, pregnant female rats, or female rats and their nursing offspring (all receivers). In response to secondary stress, levels of calcitonin gene-related peptide, active forms of the mitogen activated protein kinases ERK, JNK, and p38, and astrocyte expression of glial fibrillary acidic protein were significantly elevated in the spinal trigeminal nucleus in day 45 offspring when compared to naïve offspring. In addition, increased nuclear expression of ERK and p38 was observed in trigeminal ganglion neurons. Our results demonstrate that secondary traumatic stress promotes cellular events associated with prolonged trigeminal sensitization in the offspring, and provides a mechanism of how early life stress may function as a risk factor for migraine.