Association of Social Network with Physical Function Among Community-Dwelling Older Adults in Rural Thailand: A Cross-Sectional Study.

Purpose: As the number of older adults in society increases, their social roles and networks, as well as their physical function, decrease. This study aimed to clarify the association between social networks and physical function among people aged ≥ 60 years in rural Thailand.

Patients And Methods: This cross-sectional study was conducted in the Photharam District, Ratchaburi Province, Thailand.

New protocol for contrast media reduction in atrial fibrillation ablation-planning CT with dual region of interest.

Introduction: Many patients with atrial fibrillation have impaired renal function, and therefore pre-operative CT for radiofrequency catheter ablation should minimize the use of contrast media. This study describes a dual-region-of-interest (D-ROI) protocol for the scanning of pulmonary veins and left atrium (PVs-LA) with less contrast media and optimized scan timing compared to the single-region-of-interest (S-ROI) protocol, without compromising image quality.

Methods: This study retrospectively included 100 patients who underwent PVs-LA CT between July 2019 and February 2022.

Additional prognostic impact of plaque characterization with on-site CT-derived fractional flow reserve in coronary CT angiography.

Background: On-site computed tomography-derived fractional flow reserve (CT-FFR) is a feasible method for examining lesion-specific ischemia, and plaque analysis of coronary CT angiography (CCTA) is useful for predicting future cardiac events. However, their utility and association on a per-vessel level remain unclear.

Methods: We analyzed vessels showing 50-90 % stenosis on CCTA where planned revascularization was not performed after CCTA within 90 days.

Energy loss is related to CT fractional flow reserve progression in type 2 diabetes mellitus patients.

Background: We aimed to investigate the diagnostic value of energy loss (EL) and baseline CT fractional flow reserve (CT-FFR) computed using computational fluid dynamics to predict functional progression of coronary stenosis in patients with type 2 diabetes mellitus.

Methods: This single-center prospective study included 61 patients with type 2 diabetes mellitus (mean age, 61 years ±9 [SD]; 43 men) showing 20-70 % stenosis who underwent serial coronary CT performed at 2-year interval between October 2015 and March 2020. A mesh-free simulation was performed to calculate the CT-FFR and EL.

Coronary Artery Vorticity to Predict Functional Plaque Progression in Participants with Type 2 Diabetes Mellitus.

Purpose: To investigate whether vorticity could predict functional plaque progression better than high-risk plaque (HRP) and lesion length (LL) in individuals with type 2 diabetes mellitus.

Materials And Methods: This single-center prospective study included 61 participants (mean age, 61 years ± 9 [SD]; 43 male participants) who underwent serial coronary CT angiography at 2 years, with 20%-70% stenosis at initial CT between October 2015 and March 2020. The number of the following HRP characteristics was recorded: low attenuation, positive remodeling, spotty calcification, and napkin-ring sign.

Validation and clinical impact of novel pericoronary adipose tissue measurement on ECG-gated non-contrast chest CT.

Background And Aims: We aimed to develop a method for quantifying pericoronary adipose tissue (PCAT) on electrocardiogram (ECG)-gated non-contrast CT (NC-PCAT) and validate its efficacy and prognostic value.

Methods: We retrospectively studied two independent cohorts. PCAT was quantified conventionally.

Coronary flow disturbance assessed by vorticity as a cause of functionally significant stenosis.

Objectives: Vorticity calculated using computational fluid dynamics (CFD) could assess the flow disturbance generated by coronary stenosis. The purpose of this study was to investigate whether vorticity would be an underlying cause of functionally significant stenosis assessed by invasive fractional flow reserve (FFR).

Methods: This retrospective study included 113 patients who underwent coronary CT angiography showing intermediate stenosis and subsequent invasive FFR between December 2015 and March 2020.

Prognostic value of the optimal measurement location of on-site CT-derived fractional flow reserve.

Background: On-site computed tomography-derived fractional flow reserve (CT-FFR), using fluid structure interaction during multiple optimal diastolic phases, is of incremental diagnostic value. However, few studies have investigated prognosis, with the appropriate measurement location of CT-FFR, as a stand-alone modality. The aim of the present study was to assess the clinical impact on CT-FFR with an appropriate measurement.

Effect of Temporal Sampling Rate on Estimates of the Perfusion Parameters for Patients with Moyamoya Disease Assessed with Simultaneous Multislice Dynamic Susceptibility Contrast-enhanced MR Imaging.

Purpose: The effect of temporal sampling rate (TSR) on perfusion parameters has not been fully investigated in Moyamoya disease (MMD); therefore, this study evaluated the influence of different TSRs on perfusion parameters quantitatively and qualitatively by applying simultaneous multi-slice (SMS) dynamic susceptibility contrast-enhanced MR imaging (DSC-MRI).

Methods: DSC-MRI datasets were acquired from 28 patients with MMD with a TSR of 0.5 s.

Aorta-aware GAN for non-contrast to artery contrasted CT translation and its application to abdominal aortic aneurysm detection.

Purpose: Artery contrasted computed tomography (CT) enables accurate observations of the arteries and surrounding structures, thus being widely used for the diagnosis of diseases such as aneurysm. To avoid the complications caused by contrast agent, this paper proposes an aorta-aware deep learning method to synthesize artery contrasted CT volume form non-contrast CT volume.

Methods: By introducing auxiliary multi-resolution segmentation tasks in the generator, we force the proposed network to focus on the regions of aorta and the other vascular structures.

Multi-agent system collision model to predict the transmission of seasonal influenza in Tokyo from 2014-2015 to 2018-2019 seasons.

The objective of this study was to apply the multi-agent system (MAS) collision model to predict seasonal influenza epidemic in Tokyo for 5 seasons (2014-2015 to 2018-2019 seasons). The MAS collision model assumes each individual as a particle inside a square domain. The particles move within the domain and disease transmission occurs in a certain probability when an infected particle collides a susceptible particle.

Comparison of Brain Volume Measurements Made with 0.3- and 3-T MR Imaging.

The volumes of intracranial tissues of 40 healthy volunteers acquired from 0.3- and 3-T scanners were compared using intraclass correlation coefficients, correlation analyses, and Bland-Altman analyses. We found high intraclass correlation coefficients, high Pearson's correlation coefficients, and low percentage biases in all tissues and most of the brain regions, although small differences were observed in some areas.

Comparison of diagnostic performance in on-site based CT-derived fractional flow reserve measurements.

Background: Computed tomography fractional flow reserve (CT-FFR), which can be acquired on-site workstation using fluid structure interaction during the multiple optimal diastolic phase, has an incremental diagnostic value over conventional coronary computed tomography angiography (CCTA). However, the appropriate location for CT-FFR measurement remains to be clarified.

Method: A total of 115 consecutive patients with 149 vessels who underwent CCTA showing 30-90% stenosis with invasive FFR within 90 days were retrospectively analyzed.

International survey on residency programs in radiology: similarities and differences among 17 countries.

Objective: With the initiative of the ACR International Economics Committee, a multinational survey was conducted to evaluate radiology residency programs around the world.

Methods: A 31-question survey was developed. It included: economic issues, program size and length, resident's activities during daytime and call, academic aspects including syllabus and examinations.

Patient-specific 3D-printed coronary models based on coronary computed tomography angiography volumes to investigate flow conditions in coronary artery disease.

Background: 3D printed patient-specific coronary models have the ability to enable repeatable benchtop experiments under controlled blood flow conditions. This approach can be applied to CT-derived patient geometries to emulate coronary flow and related parameters such as Fractional Flow Reserve (FFR).

Methods: This study uses 3D printing to compare such benchtop FFR results with a non-invasive CT-FFR research software algorithm and catheter based invasive FFR (I-FFR) measurements.

A National Survey on Safety Management at MR Imaging Facilities in Japan.

Purpose: To investigate safety management at Japanese facilities performing human MRI studies.

Methods: All Japanese facilities performing human MRI studies were invited to participate in a comprehensive survey that evaluated their MRI safety management. The survey used a questionnaire prepared with the cooperation of the Safety Committee of the Japanese Society for Magnetic Resonance in Medicine.

Plaque characteristics on coronary CT angiography associated with the positive findings of fractional flow reserve and instantaneous wave-free ratio.

Background: Fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) are useful in determining indications for revascularization of coronary artery disease (CAD). Although the discordance of FFR and iFR was noted in approximately 20%, this cause has not been well established. We investigated patient background and features on coronary CT angiography (CCTA) showing not only FFR- and iFR-positive findings but also discordance between FFR ≤ 0.

Development and Validation of a Modified Three-Dimensional U-Net Deep-Learning Model for Automated Detection of Lung Nodules on Chest CT Images From the Lung Image Database Consortium and Japanese Datasets.

Rationale And Objectives: A more accurate lung nodule detection algorithm is needed. We developed a modified three-dimensional (3D) U-net deep-learning model for the automated detection of lung nodules on chest CT images. The purpose of this study was to evaluate the accuracy of the developed modified 3D U-net deep-learning model.

Method to simulate distal flow resistance in coronary arteries in 3D printed patient specific coronary models.

Background: Three-dimensional printing (3DP) offers a unique opportunity to build flexible vascular patient-specific coronary models for device testing, treatment planning, and physiological simulations. By optimizing the 3DP design to replicate the geometrical and mechanical properties of healthy and diseased arteries, we may improve the relevance of using such models to simulate the hemodynamics of coronary disease. We developed a method to build 3DP patient specific coronary phantoms, which maintain a significant part of the coronary tree, while preserving geometrical accuracy of the atherosclerotic plaques and allows for an adjustable hydraulic resistance.

A study on the prevalence, distribution and related factors of heart valve calcification using coronary CT angiography.

Background: The concept of active atherosclerotic disease has been accepted for heart valve calcification (HVC). We investigated prevalence, distribution and related factors of HVC in patients who had undergone coronary CT angiography (CCTA).

Methods: Subjects were consecutive 200 patients who underwent CCTA.

Impact of Abnormal Remote Stress Myocardial Blood Flow by Dynamic CT Perfusion on Clinical Outcomes.

The objective of this study was to investigate the incremental prognostic value for adverse events of myocardial blood flow (MBF) derived from stress computed tomography perfusion (CTP) at remote myocardium over cardiac risk factors and ischemia. We prospectively analyzed 242 patients who underwent dynamic CTP and CT angiography. Adverse events were defined as a composite of all-cause mortality, non-fatal myocardial infarction, unstable angina, heart failure requiring hospitalization, peripheral artery disease, and stroke.

Initial evaluation of a convolutional neural network used for noninvasive assessment of coronary artery disease severity from coronary computed tomography angiography data.

Purpose: Coronary computed tomography angiography (CTA) has one of the highest diagnostic sensitivities for detection of the significance of coronary artery disease (CAD); however, sensitivity is moderate and may result in increased catheterization rates. We performed an efficacy study to determine whether a trained machine learning algorithm that uses coronary CTA data may improve CAD diagnosis accuracy.

Methods: Sixty-four-patient image datasets based on coronary CTA were retrospectively collected to generate eight views considering 45° increments around the coronary artery centerline.

Work-style reform and use of information and communication technology among diagnostic radiologists in Japan: results of the 2018 JRS/JCR joint survey.

Purpose: The purpose of this study was to investigate recent trends in work-style reform and the use of information and communication technology (ICT) among board-certified diagnostic radiologists in Japan.

Materials And Methods: We conducted online questionnaire surveys of board-certified radiologists of the Japan Radiological Society (JRS) and registered training institutions. Completed surveys were obtained from 1192 radiologists and 275 training institutions (response rates of 25.