Comparative Efficacy of Non-contrast vs. Contrast-enhanced CT Radiomics in Predicting Coronary Artery Plaques Among Patients with Low Agatston Scores.

Rationale And Objectives: Patients with a low Agatston score often present with clinical signs and symptoms suggestive of coronary artery disease, despite having minimal calcium deposits. This study aimed to compare the efficacy of low-dose non-contrast cardiac CT with coronary computed tomography angiography (CCTA) in pericoronary adipose tissue (PCAT) radiomics for predicting coronary artery plaques, using CCTA as the reference standard.

Materials And Methods: This retrospective study analyzed 459 patients with suspected coronary artery disease and a coronary artery calcium score < 100 Agatston units, who were treated between June 2021 and December 2023 at a tertiary hospital.

Intratumoral and peritumoral radiomics based on ultrasound for the differentiation of follicular thyroid neoplasm.

Background: Although ultrasound (US) has been widely adopted as the preferred imaging modality for thyroid nodule evaluation, its reliability in distinguishing follicular adenomas from adenocarcinomas based on US features has been a subject of debate. The primary objective of our study was to comprehensively evaluate the efficacy of US-derived intratumoral and peritumoral radiomics in preoperatively differentiating follicular thyroid adenomas from adenocarcinomas, thereby contributing to the ongoing discussion regarding this challenging distinction.

Methods: In total, 195 patients who were pathologically diagnosed with thyroid follicular neoplasm were retrospectively enrolled in this study.

[LSTM-XGBoost Based RR Intervals Time Series Prediction Method in Hypertensive Patients].

Objective: The prediction of RR intervals in hypertensive patients can help clinicians to analyze and warn patients' heart condition.

Methods: Using 8 patients' data as samples, the RR intervals of patients were predicted by long short-term memory network (LSTM) and gradient lift tree (XGBoost), and the prediction results of the two models were combined by the inverse variance method to overcome the disadvantage of single model prediction.

Results: Compared with the single model, the proposed combined model had a different degree of improvement in the prediction of RR intervals in 8 patients.

Iodine concentration, HU accuracy, and metal artifacts evaluation on second-generation dual-layer spectral detector CT images with metal implants: a phantom study.

Background: Metal implants may affect the image quality, iodine concentration (IC), and CT Hounsfield unit (HU) quantification accuracy.

Purpose: To investigate the quantitative accuracy of IC and HU from dual-layer spectral detector (DLCT) in the presence of metal artifacts.

Material And Methods: An experimental cylindrical phantom containing eight iodine inserts and two metal inserts was designed.

Technical note: A GPU-based shared Monte Carlo method for fast photon transport in multi-energy x-ray exposures.

Background: The Monte Carlo (MC) method is an accurate technique for particle transport calculation due to the precise modeling of physical interactions. Nevertheless, the MC method still suffers from the problem of expensive computational cost, even with graphics processing unit (GPU) acceleration. Our previous works have investigated the acceleration strategies of photon transport simulation for single-energy CT.

Radiomics predict the WHO/ISUP nuclear grade and survival in clear cell renal cell carcinoma.

Objectives: This study aimed to assess the predictive value of radiomics derived from intratumoral and peritumoral regions and to develop a radiomics nomogram to predict preoperative nuclear grade and overall survival (OS) in patients with clear cell renal cell carcinoma (ccRCC).

Methods: The study included 395 patients with ccRCC from our institution. The patients in Center A (anonymous) institution were randomly divided into a training cohort (n = 284) and an internal validation cohort (n = 71).

Characteristics and mechanism of local scour reduction around spur dike using the collar in clear water.

To reduce the local scour around the spur dike, the U-shaped collar is proposed in this study. The influence of the collar's length, width, and porosity on the local scour reduction in clear water is studied by model tests and numerical simulations. Experimental studies show that the collar has a significant effect on reducing the local scour.

Analysis of the response subsidence and grouting treatment in the goaf of multi-layer inclined coal seam.

Based on existing researches, field drillings and numerical simulations are carried out in this paper to analyze the problems of subsidence control in the goaf of multi-layer inclined coal seam. Midas/GTS NX is used to build a three-dimensional calculation model of the goaf. A new method of using borehole data to check simulation parameters is proposed.

[Free trajectory cone beam computed tomography reconstruction method for synchronous scanning of geometric calibration phantom and imaging object].

In order to suppress the geometrical artifacts caused by random jitter in ray source scanning, and to achieve flexible ray source scanning trajectory and meet the requirements of task-driven scanning imaging, a method of free trajectory cone-beam computed tomography (CBCT) reconstruction is proposed in this paper. This method proposed a geometric calibration method of two-dimensional plane. Based on this method, the geometric calibration phantom and the imaging object could be simultaneously imaged.

Scatter correction based on adaptive photon path-based Monte Carlo simulation method in Multi-GPU platform.

Monte Carlo (MC)-based simulation is the most precise method in scatter correction for Cone-beam CT (CBCT). Nonetheless, the existing MC methods cannot be fully applied in clinical due to its low efficiency. The traditional MC simulations perform calculations via a particle-by-particle scheme, which leads to high computation costs because abundant photons do not reach the X-ray detector in transport.

[Interpretation of () ： schistosomiasis].

(20182020), which was formulated by 10 ministries of China, was issued on November 29, 2018. Schistosomiasis control is an important part of this plan, and the implementation of the plan provides an important basis for the health poverty alleviation and the fight against schistosomiasis in China. This paper describes the objective and principle of the plan and proposes "six actions" and supporting measures to implement the three-year tough action targeting schistosomiasis, with aims to guide the scientific implementation of the three-year tough action against schistosomiasis and facilitate the progress towards schistosomiasis elimination in China.

Patch Based Grid Artifact Suppressing in Digital Mammography.

The mammography is the first choice of breast cancer screening, which has proven to be the most effective screening method. An antiscatter grid is usually employed to enhance the contrast of image by absorbing unexpected scattered signals. However, the grid pattern casts shadows and grid artifacts, which severely degrade the image quality.

Simultaneous calibration phantom commission and geometry calibration in cone beam CT.

Geometry calibration is a vital step for describing the geometry of a cone beam computed tomography (CBCT) system and is a prerequisite for CBCT reconstruction. In current methods, calibration phantom commission and geometry calibration are divided into two independent tasks. Small errors in ball-bearing (BB) positioning in the phantom-making step will severely degrade the quality of phantom calibration.

John's Equation-based Consistency Condition and Corrupted Projection Restoration in Circular Trajectory Cone Beam CT.

In transmitted X-ray tomography imaging, the acquired projections may be corrupted for various reasons, such as defective detector cells and beam-stop array scatter correction problems. In this study, we derive a consistency condition for cone-beam projections and propose a method to restore lost data in corrupted projections. In particular, the relationship of the geometry parameters in circular trajectory cone-beam computed tomography (CBCT) is utilized to convert an ultra-hyperbolic partial differential equation (PDE) into a second-order PDE.

Iterative image reconstruction using modified non-local means filtering for limited-angle computed tomography.

Purpose: Limited-angle CT imaging is an effective technique to reduce radiation. However, existing image reconstruction methods can effectively reduce streak artifacts but fail to suppress those artifacts around edges due to incomplete projection data. Thus, a modified NLM (mNLM) based reconstruction method is proposed.

Few-view CT reconstruction via a novel non-local means algorithm.

Purpose: Non-local means (NLM) based reconstruction method is a promising algorithm for few-view computed tomography (CT) reconstruction, but often suffers from over-smoothed image edges. To address this problem, an adaptive NLM reconstruction method based on rotational invariance (ART-RIANLM) is proposed.

Methods: The method consists of four steps: 1) Initializing parameters; 2) ART reconstruction using raw data; 3) Positivity constraint of the reconstructed image; 4) Image updating by RIANLM filtering.

Stromal fibroblasts derived from mammary gland of bovine with mastitis display inflammation-specific changes.

Fibroblasts are predominant components of mammary stromal cells and play crucial roles in the development and involution of bovine mammary gland; however, whether these cells contribute to mastitis has not been demonstrated. Thus, we have undertaken biological and molecular characterization of inflammation-associated fibroblasts (INFs) extracted from bovine mammary glands with clinical mastitis and normal fibroblasts (NFs) from slaughtered dairy cows because of fractured legs during lactation. The functional contributions of INFs to normal epithelial cells were also investigated by using an in vitro co-culture model.

Iterative Image Reconstruction for Limited-Angle CT Using Optimized Initial Image.

Limited-angle computed tomography (CT) has great impact in some clinical applications. Existing iterative reconstruction algorithms could not reconstruct high-quality images, leading to severe artifacts nearby edges. Optimal selection of initial image would influence the iterative reconstruction performance but has not been studied deeply yet.

Regional Risk Evaluation of Flood Disasters for the Trunk-Highway in Shaanxi, China.

Due to the complicated environment there are various types of highway disasters in Shaanxi Province (China). The damages caused are severe, losses are heavy, and have rapidly increased over the years, especially those caused by flood disasters along the rivers in mountainous areas. Therefore, research on risk evaluations, which play important roles in the prevention and mitigation of highway disasters are very important.

Sparse-view computed tomography image reconstruction via a combination of L(1) and SL(0) regularization.

Low-dose computed tomography reconstruction is an important issue in the medical imaging domain. Sparse-view has been widely studied as a potential strategy. Compressed sensing (CS) method has shown great potential to reconstruct high-quality CT images from sparse-view projection data.

CT Image Reconstruction from Sparse Projections Using Adaptive TpV Regularization.

Radiation dose reduction without losing CT image quality has been an increasing concern. Reducing the number of X-ray projections to reconstruct CT images, which is also called sparse-projection reconstruction, can potentially avoid excessive dose delivered to patients in CT examination. To overcome the disadvantages of total variation (TV) minimization method, in this work we introduce a novel adaptive TpV regularization into sparse-projection image reconstruction and use FISTA technique to accelerate iterative convergence.

[A fast iterative reconstruction algorithm of sparse angular CT based on the selective total variation].

Aiming at the problem of high-quality image reconstruction from projection data at sparse angular views, we proposed an improved fast iterative reconstruction algorithm based on the minimization of selective image total variation (TV). The new reconstruction scheme consists of two components. Firstly, the algebraic reconstruction technique (ART) algorithm was adopted to reconstruct image that met the identity and non-negativity of projection data, and then, secondly, the selective TV minimization was used to modify the above image.

[Cone beam CT image iterative reconstruction based on Split-Bregman method].

Objective: We propose a new iterative reconstruction method based on split-Bregman method with tight frame regularization for effective and accurate reconstruction of the sparse-view cone beam CT image.

Methods: A tight frame was chosen as the regularization term for the objective function, so that the image reconstruction involves only the minimization of an objective function according to the compressed sensing theory. We utilized the split-Bregman method to tackle the task of minimization in three steps: (1) a fast calculation of the forward projection matrix; (2) introducing an intermediate variable to transform the non-differentiated L1 regularization term into the differentiated L2 regularization problem, and solving the target function using conjugate-gradient method; (3) updating the intermediate variable using shrinkage formula from Bregman method.

[ART reconstruction from few views using bilateral-filtering iterative method].

An algebraic image reconstruction from few views using bilateral-filtering iterative method was proposed due to the problem of computed tomography insufficient data in the present study. In each iteration reconstruction, we first used algebraic reconstruction technique (ART) algorithm to reconstruct an image, ensuring the non-negativity of the reconstructed image at the same time, and then performed bilateral-filtering to the above-mentioned image. In order to improve reconstructed image quality and accelerate the convergence speed, we developed a modified bilateral-filtering method.

[A method for rapidly removing ring artifacts in CT image].

Objective: To propose a new method for effectively and rapidly removing the ring artifacts in CT images based on image post-processing.

Methods: The CT image with ring artifacts in the Cartesian coordinate was first transformed into an image with line artifacts in the polar coordinate. The image in the polar coordinate was then filtered by designing a one-dimensional filter to calculate the mean and variance of each pixel after filtering, which were compared with the variance threshold value and the pixel threshold value to determine the position of the artifacts for corrections accordingly.