As one the research hotspots in recent years,radiomics,allowing a high-throughput extraction of quantitative imaging features from medical imaging with computer software,has the promising potential in assisting individualized treatment for tumor patients.Though radiomics could quantify the heterogeneity of tumor and show potential values in clinical decision making to promote precision medicine for tumor patients,there are still lots of challenges in clinically translational research of radiomics.Thus,a joint effort should be made by researchers to promote the clinical application of radiomics to assist personalized management for patients.

Objective To develop and validate a CT-based radiomics predictive model for preoperative predicting the stage of non-small cell lung cancer (NSCLC). Methods In this retrospective study, 657 patients with histologically confirmed was collected from October 2007 to December 2014.The primary dataset consisted of patients with histologically confirmed NSCLC from October 2007 to April 2012, while independent validation was conducted from May 2012 to December 2014.All the patients underwent non-enhanced and contrast-enhanced CT images scan with a standard protocol. The pathological stage (PTNM) of patients with NSCLC were determined by the intraoperative and postoperative pathological findings,and were divided into early stage(Ⅰ,Ⅱstage)and advanced stage(Ⅲ,Ⅳstage).A list of radiomics features were extracted using the software Matlab 2014a and the corresponding radiomics signature was constructed. Multivariable logistic regression analysis was performed with radiomics signature and clinical variables for developing the prediction model. The model performance was assessed with respect to discrimination using the area under the curve (AUC) of receiver operating characteristic(ROC) analysis. Results The discrimination performance of radiomics signature yielded a AUC of 0.715[95% confidence interval (CI):0.709 to 0.721] in the primary dataset and a AUC of 0.724(95% CI:0.717 to 0.731) in the validation dataset. On multivariable logistic regression, radiomics signature, tumor diameter, carcinoembryonic antigen (CEA) level, and cytokeratin 19 fragment (CYFRA21-1) level were showed independently associated with the stage ( Ⅰ,Ⅱ stage vs. Ⅲ, Ⅳ stage) of NSCLC. The prediction model showed good discrimination in both primary dataset (AUC=0.787, 95%CI:0.781 to 0.793;sensitivity=73.4%, specificity=72.2% ,positive predictive value=0.707,negative predictive value=0.868) and independent validation dataset (AUC=0.777, 95% CI:0.771 to 0.783,sensitivity=91.3% ,specificity=67.3% ,positive predictive value=0.607, negative predictive value=0.946). Conclusion The radiomics predictive model, which integrated with the radiomics signature and clinical characteristics can be used as a promising and applicable adjunct approach for preoperatively predicting the clinical stage (Ⅰ,Ⅱ stage vs. Ⅲ,Ⅳ stage) of patients with NSCLC.

With the continuous development of CT technology,coronary artery CT angiography (CCTA) has been clinically recognized as a rapid and accurate examination method.At the same time,its radiation effects and the toxic effects of contrast agents have also attracted everyone's attention.At present,many new techniques for reducing radiation dose and iodine dosage of contrast medium are used in clinical practice.This paper aims to review the dual-low scanning techniques and progress of CCTA in recent years.

In recent years, digital radiography (DR) system is widely used in China, and digital X-ray radiography is one of the most common examinations for bone and joint. Optimizing the osteoarthrographic technique, standardizing osteoarthrogram, and summarizing the requirements for radiation protection, will further enhance the clinical application value of digital X-ray imaging in bone and joint examination. Referring to domestic and foreign literatures, and combining the clinical situation of Guangdong-Hong Kong-Macao Greater Bay Area, the experts recruited by the Guangdong-Hong Kong-Macao Greater Bay Area Imaging Technology Alliance reach a consensus on the technique and protection specifications for bone and joint examination to guide and standardize the work related to X-ray examination of bone and joint in the medical imaging department of medical institutions at all levels in the Greater Bay Area.

Objective:To investigate the feasibility of reducing radiation dose in coronary CT angiography for patients with arrhythmia with absolute phase and narrow window in prospective electrocardiogram-gating.Methods:200 patients with arrhythmia underwent coronary CT angiography procedure with prospective electrocardiogram-gating adaptive sequence in dual source CT were randomly divided into 2 groups according to the scan mode. Group A was scanned with absolute phase and narrow window(250-450 ms) and group B uesd relative phase and wide window (30%-75%). The other parameters and injection protocol of contrast media were the same in 2 groups. Both image quality and radiation dose of the 2 groups were analyzed.Results:No significant difference of image quality was found between the 2 groups. CTDI vol, DLP, E of group A were all lower than those in group B [CTDI vol : (16.71±8.35) vs.(29.35±17.90)mGy , DLP: (231.04±114.86) vs.(398.27±238.40)mGy·cm , E: (3.23±1.60) vs.(5.57±3.33)mSv, t=-6.40, -6.32、-6.32, P<0.05] . The patients with repeat scan cycles in group A and group B were 81 vs. 22 for 0 cycle , 17 vs. 62 for 1 cycle, 2 vs. 10 for 2 cycles, 0 vs. 6 for 3 cycles( χ2=70.76, P<0.05). Conclusions:The prospective electrocardiogram-gating adaptive CCTA sequence with absolute phase and narrow window can reduce radiation dose while the image quality meets the requirementsfor patients with arrhythmia.

Objective To explore the relationship between radiomics signatures based on DWI and dynamic contrast-enhanced MRI (DCE-MRI) and molecular subtypes of breast cancer.Methods A retrospective analysis of 79 female breast cancer patients, with single mass, clear molecular subtypes and preoperative breast MRI scanning (obtaining DCE-MRI and ADC images), of Guangdong General Hospital from June 2015 to June 2016,were performed.Traditional quantitative parameters,including ADC value and initial enhancement rate(IER),were recorded.Texture analysis were performed on ADC map and DCE map, with manual segmentation and extraction of radiomic features,and Manual segmentation was performed on ADC map and DCE map, radiomics features were extracted and 10 radiomics signatures were finally selected after dimension reduction. Four molecular subtypes of breast cancer were classified by immunohistochemical detection of pathological specimens, including Luminal A, Luminal B, human epidermal growth factor receptor 2 (HER2) overexpression and triple negative (TN). Univariate logistic regression analysis was used for assessing the performance of ADC values, IER values and radiomics signatures to independently predict molecular subtypes groups.Multivariate logistic regression analysis was performed to establish predicting models, then receiver operating characteristic curves (ROC) were drawn and areas under ROC curve were calculated to compare the diagnostic performance of each model. The Hosmer-Lemeshow test was performed to test the goodness of model fitness. Results There were 29 cases of Luminal A, 39 cases of Luminal B, 5 cases of HER2 overexpression and 6 cases of TN breast cancer patients.Univariate logistic regression analysis was used to assess the ability of traditonal MRI parameters of ADC and IER values and ten of the radiomics siganitures in classifying molecular subtypes,results showed that the AUC values of ADC and IER values, were both less than 0.70 (range 0.516 to 0.605), which indicated valueless;at least one radiomic signature had AUC greater than 0.70 when identifying each molecular subtype, and AUC of DCE_L_G_2.5_autocorrelation achieved the highest value of 0.941 in identifying TN and non-TN subtypes.Multivariate logistic regression analysis were performed to obtain the best model, results showed that the AUCs for classifying Luminal A and non-Luminal A, Luminal B and non-Luminal B, TN and non-TN subtypes were 0.786 and 0.733 And 0.941, respectively. The Hosmer-Lemeshow test showed that the P values of all models were larger than 0.10 (0.156, 0.204 and 0.820,respectively),indicating that there was no significant difference between the predicted and observed values of each model established, these models were all fitted good. Conclusion The radiomics features based on ADC map and DCE map can help to identify the molecular subtypes of breast cancer,especially for the identification of TN type breast cancer.

Cardiovascular disease is the leading cause of death among Chinese residents, and non-invasive imaging technology has important value in the diagnosis and treatment of cardiovascular disease. Cardiac magnetic resonance (CMR) can characterize cardiac pathophysiological information from multiple dimensions, including cardiac structure, function, tissue characteristics, and microstructure, through multi parameter and multi sequence " one-stop" imaging. This article will focus on new technologies such as CMRT1 mapping, feature tracking, and diffusion tensor imaging, and explain their applications and progress in the diagnosis, efficacy monitoring, and prognosis prediction of various myocardial lesions such as non ischemic heart disease and ischemic heart disease.

Objective To study the feasibility of applying electronic cleaning to intestinal contents tagging by diatrizoate meglumine for single-source dual-energy CT colonography with sequential acquisitions and volume scanning.Methods Twenty-four volunteers had fine effect of intestinal contents tagging by diatrizoate meglumine,good colorectal distension effect,fine image quality of dual-energy fusion colorectal images,and with informed consents were enrolled in this study.The single-source dual-energy CT colonography with sequential acquisitions and volume scanning was performed with an Acquilion ONE 320 row CT scanner,tube voltage 135 kVp/80 kVp.The intestinal contents conducted the dual-energy electronic cleaned based on decomposition of intestinal contents tagging by diatrizoate meglumine,soft tissue and air.The intestinal contents in one segment of intestinal lumen being 100％ electronically cleaned served as the basic standard,the electronic cleaning effects were divided into the 5 grades:excellent,good,moderate,fair and poor;and grade 1-3 were effective fecal electronic cleaning.Results The grade 1,2,3,4,5 of electronic cleaning effect for solid as the main intestinal contents were 22.2％,53.3％,17.8％,6.7％ and 0％ respectively;and which of electronic cleaning effect for liquid as the main intestinal contents were 47.5％,47.5％,5.0％,0％ and 0％ respectively.The together total effective electronic cleaning of intestinal contents was 97.9％ and the electronic cleaning effect was good.Conclusion Electronic cleaning could be used in the intestinal contents tagging by diatrizoate meglumine for single-source dual-energy CT colonography with sequential acquisitions and volume scanning.