Technique and protocols for cardiothoracic time-resolved contrast-enhanced magnetic resonance angiography sequences: a systematic review.

AIM: To review contrast medium administration protocols used for cardiothoracic applications of time-resolved, contrast-enhanced magnetic resonance angiography (MRA) sequences. MATERIALS AND METHODS: A systematic search of the literature (Medline/EMBASE) was performed to identify articles utilising time-resolved MRA sequences, focusing on type of sequence, adopted technical parameters, contrast agent (CA) issues, and acquisition workflow. Study design, year of publication, population, magnetic field strength, type, dose, and injection parameters of CA, as well as technical parameters of time-resolved MRA sequences were extracted. RESULTS: Of 117 retrieved articles, 16 matched the inclusion criteria. The study design was prospective in 9/16 (56%) articles, and study population ranged from 5 to 185 patients, for a total of 506 patients who underwent cardiothoracic time-resolved MRA. Magnetic field strength was 1.5 T in 13/16 (81%), and 3 T in 3/16 (19%) articles. The administered CA was gadobutrol (Gadovist) in 6/16 (37%) articles, gadopentetate dimeglumine (Magnevist) in 5/16 (31%), gadobenate dimeglumine (MultiHance) in 2/16 (13%), gadodiamide (Omniscan) in 2/16 (13%), gadofosveset trisodium (Ablavar, previously Vasovist) in 1/16 (6%). CA showed highly variable doses among studies: fixed amount or based on patient body weight (0.02-0.2 mmol/kg) and was injected with a flow rate ranging 1-5 ml/s. Sequences were TWIST in 13/16 (81%), TRICKS in 2/16 (13%), and CENTRA 1/16 articles (6%). CONCLUSION: Time-resolved MRA sequences were adopted in different clinical settings with a large spectrum of technical approaches, mostly in association with different CA dose, type, and injection method. Further studies in relation to specific clinical indications are warranted to provide a common standardised acquisition protocol.

State-level estimates of childhood obesity prevalence in the United States corrected for report bias.

BACKGROUND/OBJECTIVES: State-specific obesity prevalence data are critical to public health efforts to address the childhood obesity epidemic. However, few states administer objectively measured body mass index (BMI) surveillance programs. This study reports state-specific childhood obesity prevalence by age and sex correcting for parent-reported child height and weight bias. SUBJECTS/METHODS: As part of the Childhood Obesity Intervention Cost Effectiveness Study (CHOICES), we developed childhood obesity prevalence estimates for states for the period 2005-2010 using data from the 2010 US Census and American Community Survey (ACS), 2003-2004 and 2007-2008 National Survey of Children's Health (NSCH) (n=133 213), and 2005-2010 National Health and Nutrition Examination Surveys (NHANES) (n=9377; ages 2-17). Measured height and weight data from NHANES were used to correct parent-report bias in NSCH using a non-parametric statistical matching algorithm. Model estimates were validated against surveillance data from five states (AR, FL, MA, PA and TN) that conduct censuses of children across a range of grades. RESULTS: Parent-reported height and weight resulted in the largest overestimation of childhood obesity in males ages 2-5 years (NSCH: 42.36% vs NHANES: 11.44%). The CHOICES model estimates for this group (12.81%) and for all age and sex categories were not statistically different from NHANES. Our modeled obesity prevalence aligned closely with measured data from five validation states, with a 0.64 percentage point mean difference (range: 0.23-1.39) and a high correlation coefficient (r=0.96, P=0.009). Estimated state-specific childhood obesity prevalence ranged from 11.0 to 20.4%. CONCLUSION: Uncorrected estimates of childhood obesity prevalence from NSCH vary widely from measured national data, from a 278% overestimate among males aged 2-5 years to a 44% underestimate among females aged 14-17 years. This study demonstrates the validity of the CHOICES matching methods to correct the bias of parent-reported BMI data and highlights the need for public release of more recent data from the 2011 to 2012 NSCH.

An economic evaluation of strategies to ensure safer drinking water in the homes of families with young children in select United States locations.

Introduction: In the United States, safe, accessible drinking water is not equitable due to source water contamination, unreliable water treatment, or hazardous plumbing infrastructure. Drinking water free of lead, nitrates, and arsenic is vital for infant and young children's health. Methods: Researchers conducted a study combining single-case study review methods and economic evaluation for 6 US policies or programs. Researchers used case-study findings, activity-based costing, publicly available US population data, and existing literature to create 5-year cost projections (2020-2024) for strategies to address lead, nitrates, or arsenic in drinking water from private wells or community water systems for families with low incomes and young children aged 0-5y. Researchers estimated the number of households reached and the costs by activity and payer of implementing each policy or program using case-specific geographic location and eligibility criteria. Results: The total number of households reached varied from 295 to 135,000 depending on water source, population of focus, and geographic location. Focused strategies reached higher proportions of families with low incomes and young children. Community water system and state-wide strategies had the broadest reach. The total annual program cost per household that received information about their water quality ranged from $75 to $2,780. Of this cost, the portion paid by the household varied from $0.12 to $1,590, not including mitigation. Conclusions: These findings can inform local decisions about policies and programs in communities seeking to increase awareness and access to safer drinking water, particularly in homes of families with low incomes and young children.

Development of lumbar spine MRI referrals vetting models using machine learning and deep learning algorithms: Comparison models vs healthcare professionals.

INTRODUCTION: Referrals vetting is a necessary daily task to ensure the appropriateness of radiology referrals. Vetting requires extensive clinical knowledge and may challenge those responsible. This study aims to develop AI models to automate the vetting process and to compare their performance with healthcare professionals. METHODS: 1020 lumbar spine MRI referrals were collected retrospectively from two Irish hospitals. Three expert MRI radiographers classified the referrals into indicated or not indicated for scanning based on iRefer guidelines. The reference label for each referral was assigned based on the majority voting. The corpus was divided into two datasets, one for the models' development with 920 referrals, and one included 100 referrals used as a held-out for the final comparison of the AI models versus national and international MRI radiographers. Three traditional models were developed: SVM, LR, RF, and two deep neural models, including CNN and Bi-LSTM. For the traditional models, four vectorisation techniques applied: BoW, bigrams, trigrams, and TF-IDF. A textual data augmentation technique was applied to investigate the influence of data augmentation on the models' performances. RESULTS: RF with BoW achieved the highest AUC reaching 0.99. CNN model outperformed Bi-LSTM with AUC = 0.98. With the augmented dataset, the performance significantly improved with an increase in F1 scores ranging from 1% to 7%. All models outperformed the national and international radiographers when compared on the hold-out dataset. CONCLUSION: The models assigned the referrals' appropriateness with higher accuracies than the national and international radiographers. Applying data augmentation significantly improved the models' performances. IMPLICATIONS FOR PRACTICE: The outcomes suggest that the use of AI for checking referrals' eligibility could serve as a supporting tool to improve the referrals' management in radiology departments.

An investigation of lumbar spine magnetic resonance referrals in two Irish university teaching centres: Radiology clinical judgement versus iRefer guideline compliance.

INTRODUCTION: With the annual increase in medical imaging demand, the appropriateness of the lumbar spine magnetic resonance imaging LSMRI referrals is worldwide gaining attention. This study aims to determine the appropriateness of LSMRI referrals and compare radiology clinical decisions to iRefer compliance based solely on referral text content. METHODS: Referral text was extracted from 1021 LSMRI referrals. Two review panels were recruited: three expert radiologists and three MRI radiographers. Radiologists classified cases as indicated or not indicated for scanning based on their clinical judgement. The radiographers classified based solely on iRefer guidelines. Majority voting for each case was applied to both review panels and reviewer agreement was tested using Kappa analysis. Logistic regression models were developed to identify medical disciplines associated with high rates of indicated referrals. RESULTS: 21.7% and 11.9% of the cases were found not indicated for MRI for radiologists and radiographers, respectively. Radiology review identified 18% of the GPs referrals as not indicated and 17% in the radiographers' review. Panel agreement was fair: Kappa values of 0.23 and0.26 for the radiologists and radiographers respectively. Neurosurgery was associated with the highest rate of indicated referrals across both review panels: oncology referrals raised the highest number of open comments. CONCLUSION: The study identified a lower number of not indicated referrals compared to previous research. Findings indicate the importance of both guidelines compliance and clinical judgement to optimise practice. IMPLICATIONS FOR PRACTICE: Findings in this study found that even when strict instructions were given to the MR radiographers to vet referrals using the iRefer guidelines, ambiguity within the guidelines resulted in variations in decision-making. This suggests that detailed protocols are required to support radiographers in the vetting process to ensure a standardised approach.

Evaluation of optimised 3D turbo spin echo and gradient echo MR pulse sequences of the knee at 3T and 1.5T.

INTRODUCTION: To investigate the impact of parameter optimisation for novel three-dimensional 3D sequences at 1.5T and 3T on resultant image quality. METHODS: Following institutional review board approval and acquisition of informed consent, MR phantom and knee joint imaging on healthy volunteers (n = 16) was performed with 1.5 and 3T MRI scanners, respectively incorporating 8- and 15-channel phased array knee radiofrequency coils. The MR phantom and healthy volunteers were prospectively scanned over a six-week period. Acquired sequences included standard two-dimensional (2D) turbo spin echo (TSE) and novel three-dimensional (3D) TSE PDW (SPACE) both with and without fat-suppression, and T2∗W gradient echo (TrueFISP) sequences. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured for knee anatomical structures. Two musculoskeletal radiologists evaluated anatomical structure visualisation and image quality. Quantitative and qualitative findings were investigated for differences using Friedman tests. Inter- and intra-observer agreements were determined with κ statistics. RESULTS: Phantom and healthy volunteer images revealed higher SNR for sequences acquired at 3T (p-value <0.05). Generally, the qualitative findings ranked images acquired at 3T higher than corresponding images acquired at 1.5T (p < 0.05). 3D image data sets demonstrated less sensitivity to partial volume averaging artefact (PVA) compared to 2D sequences. Inter- and intra-observer agreements for evaluation across all sequences ranged from 0.61 to 0.79 and 0.71 to 0.92, respectively. CONCLUSION: Both 2D and 3D images demonstrated higher image quality at 3T than at 1.5T. Optimised 3D sequences performed better than the standard 2D PDW TSE sequence for contrast resolution between cartilage and joint fluid, with reduced PVA artefact. IMPLICATIONS FOR PRACTICE: With rapid advances in MRI scanner technology, including hardware and software, the optimisation of 3D MR pulse sequences to reduce scan time while maintaining image quality, will improve diagnostic accuracy and patient management in musculoskeletal MRI.

Radiographers' assessment of referrals for CT and MR imaging using a web-based data collection tool.

INTRODUCTION: There is limited research related to the radiographers' role in assessing of radiology referrals to justify imaging. This study investigated radiographers' compliance with guidelines in the assessment of CT and MRI referrals and factors that influenced their performance. METHODS: This research was facilitated by the EFRS Research Hub at ECR 2019. Five radiology referral scenarios for CT and/or MRI were distributed to radiographers, as determined by their scope of practice, who volunteered at the Research Hub. A web-based data collection tool was used. The radiographers were required to determine the appropriateness of each referral, highlight any concerns and recommend suitable investigations if applicable. Linear regression analysis was used to determine whether postgraduate qualification, grade/role of the radiographer and use of guidelines influenced the radiographers' performance in assessing the referrals. RESULTS: Participants originated from 24 countries (n = 51 CT, n = 40 MRI), the majority originating from the UK, Ireland, Italy, Spain, Norway and Austria. Responses consistent with guidelines were 58% and 57% for CT and MRI, respectively. Possession of an MSc qualification in CT was a significant factor of influence for a higher consistency with guidelines (p = 0.02) in CT. Employment as a radiographer in a lead professional role and/or educator was a significant factor of influence for a higher consistency with guidelines in MRI (p = 0.01). CONCLUSION: A total of 58% for CT and 57% for MRI of the radiographers' responses complied with guidelines. Factors such as postgraduate education and leading professional roles are associated with better performance. IMPLICATIONS FOR PRACTICE: Considering qualifications, experience and managerial role is vital before radiographers are delegated task of justifying CT and MR Imaging.

Subtraction of time-resolved magnetic resonance angiography images improves visualization of the pulmonary veins and left atrium in adults with congenital heart disease: a novel post-processing technique.

To describe a novel time-resolved magnetic resonance angiography (TR-MRA) postprocessing technique using the time-resolved angiography with interleaved stochastic trajectories (TWIST) method to evaluate the pulmonary veins and left atrium in adults with congenital heart disease undergoing cardiac MRI. Institutional ethics committee approved the study. 21 consecutive adult patients (14 female, 7 male patients, mean age 28 years) with known congenital heart disease who underwent a cardiac MRI were included. Post-processing of the TR-MRA sequences created novel "subtracted" datasets. Two independent observers reviewed the conventional TWIST and novel subtracted TWIST data sets in source and maximum intensity projection (MIP) coronal reformats to assess visualization of the pulmonary veins and left atrium based on a 5-point scale. Quantitative signal to noise (SNR) comparison was performed. TR-MRA yielded diagnostic image data in 20/21 patients (95.2%). The novel "subtracted" TR-MRA technique improved visualization of the pulmonary veins and left atrium compared to the source TR-MRA sequence in 16/20 patients (mean scores 3.34 ± 0.69 vs. 2.92 ± 0.69, p < 0.008). Further improved visualization of the pulmonary veins and left atrium was observed in the subtracted MIP TWIST sequences compared to the MIP TWIST images (mean scores 4.43 ± 0.80 vs. 3.02 ± 0.87 vs., p < 0.001). No significant SNR difference between the source and novel subtracted group was observed (85.4 vs. 70.4, p = 0.57). Compared to source TR-MRA images, subtraction of TR-MRA images is a novel postprocessing technique that improves visualization of the pulmonary veins and left atrium in a substantial number of patients.

Research questions concerning insulin-like growth factor-1.

The Harvard Center for Cancer Prevention (HCCP) convened a workshop on June 4, 1999 in Boston, MA. The objectives of the meeting were to briefly review the current state of knowledge in the area of insulin-like growth factor-1 physiology as related to cancer risk, to define the area's major remaining gaps in knowledge, and lastly to discuss research opportunities.

Women and smoking in Hollywood movies: a content analysis.

OBJECTIVES: We analyzed the portrayal of smoking in Hollywood films starring 10 popular actressess. METHODS: Five movies were randomly sampled for each actress, for a total of 96 hours of film footage that was analyzed in 1116 5-minute intervals. RESULTS: Leading female actors were as likely to smoke in movies aimed at juvenile audiences (PG/PG-13) as in R-rated movies, whereas male actors were 2.5 times more likely to smoke in R-rated movies. PG/PG-13-rated movies were less likely than R-rated movies to contain negative messages about smoking. CONCLUSIONS: Smoking is highly prevalent in Hollywood films featuring popular actressess and may influence young audiences for whom movie stars serve as role models.

Self-reactive, T cell receptor-gamma delta+, lymphocytes from the intestinal epithelium of weanling mice.

Intraepithelial T lymphocytes (IEL) are dispersed throughout the intestinal epithelial lining but their role in cellular immune defense is unknown. Their location suggests that their highly activated state may be due to constant exposure to bacterial Ag. To study IEL specificity and function we have prepared a panel of IEL-T cell hybridomas from both adult and weanling C57B1/6 mice. Many of these expressed TCR-gamma delta, a cell type rare in peripheral lymph nodes and spleen but predominant at epithelial surfaces. We have identified a subset of gamma delta T cells from weanling mice which is self reactive, i.e., these hybrids secrete IL-2 spontaneously, without antigenic stimulation or a requirement for APC. Self-reactive TCR-gamma delta+ hybrids and lines, all of which bear a particular TCR (V gamma 1.1C gamma 4V delta 6), have previously been derived from neonatal thymus and the skin. Northern blot and immunoprecipitation analyses suggest that the self-reactive IEL hybrids also bear a C gamma 4/V delta 6 TCR. Antibody inhibition experiments showed that the self-reactivity of the IEL hybrids is TCR mediated. Spontaneous IL-2 production was blocked by soluble anti-CD3 and anti-TCR-gamma delta antibodies but not by antibodies to the TCR-alpha beta. The self-reactive IEL hybrids lack class II MHC and the class I-like proteins CD1 and TLA but express class I MHC. IEL hybrids may also require the vitronectin receptor as an accessory molecule for their activation because spontaneous IL-2 production is blocked by antibody to the vitronectin receptor as well as by the extracellular matrix protein active site peptide RGDS, but not the control peptide RGES. V gamma 1.1C gamma 4V delta 6 T cells in the thymus, skin, and intestine may represent a small and unique subpopulation of lymphocytes with a potential for autoimmune reactivity at peripheral sites.