Super High Contrast USPIO-Enhanced Cerebrovascular Angiography Using Ultrashort Time-to-Echo MRI.

Background: Ferumoxytol (Ferahame, AMAG Pharmaceuticals, Waltham, MA) is increasingly used off-label as an MR contrast agent due to its relaxivity and safety profiles. However, its potent T2∗ relaxivity limits achievable T1-weighted positive contrast and leads to artifacts in standard MRI protocols. Optimization of protocols for ferumoxytol deployment is necessary to realize its potential. Methods: We present first-in-human clinical results of the Quantitative Ultrashort Time-to-Echo Contrast Enhanced (QUTE-CE) MRA technique using the superparamagnetic iron oxide nanoparticle agent ferumoxytol for vascular imaging of the head/brain in 15 subjects at 3.0T. The QUTE-CE MRA method was implemented on a 3T scanner using a stack-of-spirals 3D Ultrashort Time-to-Echo sequence. Time-of-flight MRA and standard TE T1-weighted (T1w) images were also collected. For comparison, gadolinium-enhanced blood pool phase images were obtained retrospectively from clinical practice. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and intraluminal signal heterogeneity (ISH) were assessed and compared across approaches with Welch's two-sided t-test. Results: Fifteen volunteers (54 ± 17 years old, 9 women) participated. QUTE-CE MRA provided high-contrast snapshots of the arterial and venous networks with lower intraluminal heterogeneity. QUTE-CE demonstrated significantly higher SNR (1707 ± 226), blood-tissue CNR (1447 ± 189), and lower ISH (0.091 ± 0.031) compared to ferumoxytol T1-weighted (551 ± 171; 319 ± 144; 0.186 ± 0.066, respectively) and time-of-flight (343 ± 104; 269 ± 82; 0.190 ± 0.016, respectively), with p < 0.001 in each comparison. The high CNR increased the depth of vessel visualization. Vessel lumina were captured with lower heterogeneity. Conclusion: Quantitative Ultrashort Time-to-Echo Contrast-Enhanced MR angiography provides approximately 5-fold superior contrast with fewer artifacts compared to other contrast-enhanced vascular imaging techniques using ferumoxytol or gadolinium, and to noncontrast time-of-flight MR angiography, for clinical vascular imaging. This trial is registered with NCT03266848.

Evaluation of Prompts to Simplify Cardiovascular Disease Information Generated Using a Large Language Model: Cross-Sectional Study.

In this cross-sectional study, we evaluated the completeness, readability, and syntactic complexity of cardiovascular disease prevention information produced by GPT-4 in response to 4 kinds of prompts.

Response of Unvaccinated US Adults to Official Information About the Pause in Use of the Johnson & Johnson-Janssen COVID-19 Vaccine: Cross-Sectional Survey Study.

Using a rapid response web-based survey, we identified gaps in public understanding of the Centers for Disease Control and Prevention's messaging about the pause in use of the Johnson & Johnson-Janssen COVID-19 vaccine and estimated changes in vaccine hesitancy using counterfactual questions.

Ferumoxytol-enhanced ultrashort TE MRA and quantitative morphometry of the human kidney vasculature.

PURPOSE: To evaluate the feasibility of Quantitative Ultrashort-Time-to-Echo Contrast-Enhanced (QUTE-CE) MRA using ferumoxytol as a contrast agent for abdominal angiography in the kidney. METHODS: Four subjects underwent ferumoxytol-enhanced MRA with the 3D UTE Spiral VIBE WIP sequence at 3 T. Image quality metrics were quantified, specifically the blood Signal-to-Noise Ratio (SNR), blood-tissue Contrast-to-Noise Ratio (CNR) and Intraluminal Signal Heterogeneity (ISH) from both the aorta and inferior vena cava (IVC). Morphometric analysis of the vessels was performed using manual approach and semi-automatic approach using Vascular Modeling ToolKit (VMTK). Image quality and branching order were compared between QUTE-CE MRA and the Gadolinium (Gd) CEMRA reference image. RESULTS: QUTE-CE MRA provides a bright blood snapshot that delineates arteries and veins equally in the same scan. The maximum SNR and CNR values were 3,282 ± 1,218 and 1,295 ± 580, respectively - significantly higher than available literature values using other CEMRA techniques. QUTE-CE MRA had lower ISH and depicted higher vessel branching order (7th vs 3rd) within the kidney compared to a standard dynamic clinical Gd CEMRA scan. Morphometric analysis yielded quantitative results for the total kidney volume, total cyst volume and for diameters of the branching arterial network down to the 7th branch. Vessel curvature was significantly increased (p < 0.001) in the presence of a renal cyst compared to equivalent vessels in normal kidney regions. CONCLUSION: QUTE-CE MRA is feasible for kidney angiography, providing greater detail of kidney vasculature, enabling quantitative morphometric analysis of the abdominal and intra-renal vessels and yielding metrics relevant to vascular diseases while using a contrast agent ferumoxytol that is safe for CKD patients.

Chronic Medical Illness as a Risk Factor for Poor Mammography Screening Adherence.

Objective: The aim of this study was to determine the association between the presence of chronic medical disease and mammography screening adherence. Materials and Methods: We performed a retrospective study on women between the ages of 50 and 64 who received screening mammography in 2005 and had at least 8 years of follow-up. Demographic and clinical information was obtained from our centralized patient data registry. Women diagnosed with one or more of the following diseases for at least 3 months before their index mammogram were considered to have a chronic disease, including atrial fibrillation, congestive heart failure, Chronic Obstructive Pulmonary Disease (COPD), diabetes mellitus type II, heart disease, and/or peripheral vascular disease. Generalized estimating equations were used to evaluate for correlated observations. Multivariable regression analyses were used to evaluate the effects of selected chronic medical diseases on longitudinal engagement with routine mammography. Results: Of 9575 women identified, 1669 (17.7%) had one or more of the selected chronic medical diseases. The presence of one or more of these diseases was associated with reduced mammography screening (-0.29; confidence interval [CI] = -0.36 to -0.14; p < 0.01) compared with women without these diseases over the study period. Within this group, the presence of congestive heart failure (-0.88; CI = -0.84 to -0.45; p ≤ 0.01), COPD (-0.39; CI = -0.57 to -0.21; p ≤ 0.01), or diabetes mellitus type II (-0.37; CI = -0.57 to -0.17; p ≤ 0.01) was individually associated with reduced screening compared with women without the respective disease. Compared with women without chronic medical disease, women with multiple chronic medical diseases (-0.62; CI = -0.93 to -0.30; p ≤ 0.01) were significantly (p ≤ 0.05) less likely to receive routine screening, while no significant difference was seen in women with only one chronic medical disease (-0.18; CI = -0.39 to -0.02; p ≤ 0.08). Conclusion: Despite experiencing longer life expectancies, women with specific chronic diseases may experience additional barriers to uptake of mammography screening, which is likely compounded by the comorbidity burden of being simultaneously treated for multiple chronic conditions. Increased health care interactions seen in this group may represent missed opportunities to improve screening adherence.

Advanced imaging in acute and chronic deep vein thrombosis.

Deep venous thrombosis (DVT) affecting the extremities is a common clinical problem. Prompt imaging aids in rapid diagnosis and adequate treatment. While ultrasound (US) remains the workhorse of detection of extremity venous thrombosis, CT and MRI are commonly used as the problem-solving tools either to visualize the thrombosis in central veins like superior or inferior vena cava (IVC) or to test for the presence of complications like pulmonary embolism (PE). The cross-sectional modalities also offer improved visualization of venous collaterals. The purpose of this article is to review the established modalities used for characterization and diagnosis of DVT, and further explore promising innovations and recent advances in this field.

Open access: the changing face of scientific publishing.

The debate on open access to scientific literature that has been raging in scholarly circles for quite some time now has been fueled further by the recent developments in the realm of the open access movement. This article is a short commentary on the current scenario, challenges, and the future of the open access movement.