A delta-radiomics model for preoperative prediction of invasive lung adenocarcinomas manifesting as radiological part-solid nodules.

Purpose: This study aims to explore the value of the delta-radiomics (DelRADx) model in predicting the invasiveness of lung adenocarcinoma manifesting as radiological part-solid nodules (PSNs). Methods: A total of 299 PSNs histopathologically confirmed as lung adenocarcinoma (training set, n = 209; validation set, n = 90) in our hospital were retrospectively analyzed from January 2017 to December 2021. All patients underwent diagnostic noncontrast-enhanced CT (NCECT) and contrast-enhanced CT (CECT) before surgery. After image preprocessing and ROI segmentation, 740 radiomic features were extracted from NCECT and CECT, respectively, resulting in 740 DelRADx. A DelRADx model was constructed using the least absolute shrinkage and selection operator logistic (LASSO-logistic) algorithm based on the training cohort. The conventional radiomics model based on NCECT was also constructed following the same process for comparison purposes. The prediction performance was assessed using area under the ROC curve (AUC). To provide an easy-to-use tool, a radiomics-based integrated nomogram was constructed and evaluated by integrated discrimination increment (IDI), calibration curves, decision curve analysis (DCA), and clinical impact plot. Results: The DelRADx signature, which consisted of nine robust selected features, showed significant differences between the AIS/MIA group and IAC group (p < 0.05) in both training and validation sets. The DelRADx signature showed a significantly higher AUC (0.902) compared to the conventional radiomics model based on NCECT (AUC = 0.856) in the validation set. The IDI was significant at 0.0769 for the integrated nomogram compared with the DelRADx signature. The calibration curve of the integrated nomogram demonstrated favorable agreement both in the training set and validation set with a mean absolute error of 0.001 and 0.019, respectively. Decision curve analysis and clinical impact plot indicated that if the threshold probability was within 90%, the integrated nomogram showed a high clinical application value. Conclusion: The DelRADx method has the potential to assist doctors in predicting the invasiveness for patients with PSNs. The integrated nomogram incorporating the DelRADx signature with the radiographic features could facilitate the performance and serve as an alternative way for determining management.

Radiomics signature on CECT as a predictive factor for invasiveness of lung adenocarcinoma manifesting as subcentimeter ground glass nodules.

Controversy and challenges remain regarding the cognition of lung adenocarcinomas presented as subcentimeter ground glass nodules (GGNs). Postoperative lymphatic involvement or intrapulmonary metastasis is found in approximately 15% to 20% of these cases. This study aimed to develop and validate a radiomics signature to identify the invasiveness of lung adenocarcinoma appearing as subcentimeter ground glass nodules. We retrospectively enrolled 318 subcentimeter GGNs with histopathology-confirmed adenocarcinomas in situ (AIS), minimally invasive adenocarcinomas (MIA) and invasive adenocarcinomas (IAC). The radiomics features were extracted from manual segmentation based on contrast-enhanced CT (CECT) and non-contrast enhanced CT (NCECT) images after imaging preprocessing. The Lasso algorithm was applied to construct radiomics signatures. The predictive performance of radiomics models was evaluated by receiver operating characteristic (ROC) analysis. A radiographic-radiomics combined nomogram was developed to evaluate its clinical utility. The radiomics signature on CECT (AUC: 0.896 [95% CI 0.815-0.977]) performed better than the radiomics signature on NCECT data (AUC: 0.851[95% CI 0.712-0.989]) in the validation set. An individualized prediction nomogram was developed using radiomics model on CECT and radiographic model including type, shape and vascular change. The C index of the nomogram was 0.915 in the training set and 0.881 in the validation set, demonstrating good discrimination. Decision curve analysis (DCA) revealed that the proposed model was clinically useful. The radiomics signature built on CECT could provide additional benefit to promote the preoperative prediction of invasiveness in patients with subcentimeter lung adenocarcinomas.

A Computed Tomography-Derived Radiomics Approach for Predicting Uncommon EGFR Mutation in Patients With NSCLC.

PURPOSE: This study aims to develop a CT-based radiomics approach for identifying the uncommon epidermal growth factor receptor (EGFR) mutation in patients with non-small cell lung cancer (NSCLC). METHODS: This study involved 223 NSCLC patients (107 with uncommon EGFR mutation-positive and 116 with uncommon EGFR mutation-negative). A total of 1,269 radiomics features were extracted from the non-contrast-enhanced CT images after image segmentation and preprocessing. Support vector machine algorithm was used for feature selection and model construction. Receiver operating characteristic curve analysis was applied to evaluate the performance of the radiomics signature, the clinicopathological model, and the integrated model. A nomogram was developed and evaluated by using the calibration curve and decision curve analysis. RESULTS: The radiomics signature demonstrated a good performance for predicting the uncommon EGFR mutation in the training cohort (area under the curve, AUC = 0.802; 95% confidence interval, CI: 0.736-0.858) and was verified in the validation cohort (AUC = 0.791, 95% CI: 0.642-0.899). The integrated model combined radiomics signature with clinicopathological independent predictors exhibited an incremental performance compared with the radiomics signature or the clinicopathological model. A nomogram based on the integrated model was developed and showed good calibration (Hosmer-Lemeshow test, P = 0.92 in the training cohort and 0.608 in the validation cohort) and discrimination capacity (AUC of 0.816 in the training cohort and 0.795 in the validation cohort). CONCLUSION: Radiomics signature combined with the clinicopathological features can predict uncommon EGFR mutation in NSCLC patients.

Coronary Computed Tomography (CT) Angiography Characteristics of High-Risk Plaque: Correlation with Stress Myocardial Perfusion Imaging in Patients with Moderate Coronary Stenosis.

BACKGROUND The aim of this study was to investigate the ability of coronary computed tomographic angiography (CCTA) characteristics of high-risk plaque (HRP) in moderate stenosis to improve differentiation of myocardial ischemia detected by stress CT perfusion (CTP) imaging. MATERIAL AND METHODS Sixty-two patients with coronary plaques and moderate stenosis confirmed by invasive coronary angiography (ICA) had stress CTP and 26 of these patients were found to have myocardial ischemia. The other 36 patients without myocardial ischemia were defined as controls. Characteristics of major plaques on CCTA images of the ischemia and non-ischemia groups were analyzed and compared. RESULTS Differences between the 2 groups were observed in plaque volume, burden and rough inner surface necrotic core volume, plaque-lipid interface and plaque length. In a multivariable analysis, plaque burden and necrotic core volume were significantly associated with myocardial ischemia: plaque burden odds ratio (OR) was 1.28 (95% confidence interval [CI], 1.12-1.48); necrotic core volume OR was 1.78 (95% CI, 1.03-1.34). Compared with other quantitative measurements, optimized thresholds for plaque burden (area under the curve was 0.852) and necrotic core volume (area under the curve was 0.730) showed significantly higher diagnostic performance for ischemia with threshold values of 60.8% and 11.25 mm³, respectively. CONCLUSIONS CCTA characteristics of major plaques may improve the discrimination of ACS patients with myocardial ischemia on stress CTP.

Use of contrast-enhanced computed tomographic imaging to diagnose and evaluate Behçet's disease with vascular complications.

In the present study, multi-slice CT results of patients with Behçet's disease (BD) and vascular complications were retrospectively evaluated. From January 2016 to May 2018, 45 of 361 patients with BD were diagnosed with vascular involvement. The clinical background, laboratory parameters and response to therapy of those patients were assessed. The following characteristics of vascular aneurysms were analyzed: Maximum diameter, length, wall thickness, borders, luminal changes, mural thrombus, cystic change of the vessel walls, asymmetric bulging of the right part of the aortic wall (RP type) and calcific plaques. The 45 BD patients analyzed included 37 males and 8 females with a median age of 40 years (30-49 years). Significant differences were observed among genders regarding age, ocular disorders and digestive-tract ulceration. A total of 42 aneurysms were identified with a mean diameter of 43 mm. Most aneurysmal walls (88%) were homogeneously enhanced on contrast-enhanced CT. Comparison of groups classified by aortic and larger arterial aneurysms indicated that aneurysms occurring in the aorta were more likely to form a mural thrombus, have a thicker wall (P<0.001) and unclear borders (P=0.036), to be of the RP type (P=0.003) and have a longer extension (P=0.001) compared with those in larger arteries. Unclear border of the aneurysmal wall was the only radiologic predictor correlated with an elevated erythrocyte sedimentation rate (P<0.001). In conclusion, characteristic CT imaging features of aneurysms may help to diagnose vascular involvement of BD and assess its severity, particularly in the absence of the classical clinical manifestations.

Analysis of CT morphologic features and attenuation for differentiating among transient lesions, atypical adenomatous hyperplasia, adenocarcinoma in situ, minimally invasive and invasive adenocarcinoma presenting as pure ground-glass nodules.

Thin-section computed tomography (TSCT) imaging biomarkers are uncertain to distinguish progressive adenocarcinoma from benign lesions in pGGNs. The purpose of this study was to evaluate the usefulness of TSCT characteristics for differentiating among transient (TRA) lesions, atypical adenomatous hyperplasia (AAH), adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA) and invasive adenocarcinoma (IAC) presenting as pure ground-glass nodules (pGGNs). Between January 2016 and January 2018, 255 pGGNs, including 64 TRA, 22 AAH, 37 AIS, 108 MIA and 24 IAC cases, were reviewed on TSCT images. Differences in TSCT characteristics were compared among these five subtypes of pGGNs. Logistic analysis was performed to identify significant factors for predicting MIA and IAC. Progressive pGGNs were more likely to be round or oval in shape, with clear margins, air bronchograms, vascular and pleural changes, creep growth, and bubble-like lucency than were non-progressive pGGNs. The optimal cut-off values of the maximum diameter for differentiating non-progressive from progressive pGGNs and IAC from non-IAC were 6.5 mm and 11.5 mm, respectively. For the prediction of IAC vs. non-IAC and non-progressive vs. progressive adenocarcinoma, the areas under the receiver operating characteristics curves were 0.865 and 0.783 for maximum diameter and 0.784 and 0.722 for maximum CT attenuation, respectively. The optimal cut-off values of maximum CT attenuation were -532 HU and -574 HU for differentiating non-progressive from progressive pGGNs and IAC from non-IAC, respectively. Maximum diameter, maximum attenuation and morphological characteristics could help distinguish TRA lesions from MIA and IAC but not from AAH. So, CT morphologic characteristics, diameter and attenuation parameters are useful for differentiating among pGGNs of different subtypes.

Immunoglobulin G4-related disease complicated with vascular lesions: CT findings in 21 patients.

PURPOSE: We aimed to analyze multislice computed tomography (MSCT) imaging features of vasculitis in immunoglobulin G4-related disease (IgG4-RD). METHODS: In this retrospective study, we diagnosed 21 definite or possible IgG4-RD patients (71.4% male; mean age, 52.1±4.5 years) with vasculitis by MSCT and pathologic examination. The clinical background, laboratory analysis, pathologic results, CT images, and response to therapy were assessed and analyzed. RESULTS: Under enhanced MSCT, 50 vasculitic lesions were identified and were divided into five types (types A-E) according to the CT findings on the basis of luminal changes. There were more vasculitic lesions observed below the diaphragm (n=30) than above it (n=20). Aneurysms and aneurysmal dilatation were more likely to be found in the aortaventralis (n=5), aortic arch (n=3) and iliac arteries (n=3). Most of the vascular lesions were characterized by wall thickening with a normal lumen (n=15) and slight stenosis (n=22). The affected vascular walls were all thickened between 4 and 18 mm. The walls of 19 patients (90.4%) were well circumscribed. The wall thickness of the aorta, including the aortaventralis and aortic arch, was more notable than that of the other vascular sites. Fourteen patients were followed up for 2-24 months. Wall thickness decreased in all cases. The average maximum thicknesses before and after therapy were 12.2±2.7 mm and 6.1±1.8 mm, which were significantly different (P < 0.001). The lumens of two patients were found to be slightly enlarged, while those of the other cases were unchanged after therapy. CONCLUSION: IgG4-RD vascular lesions can be divided into five types, which are more likely to be present in the aorta and its main branches, and can rapidly diminish after steroid therapy. The lumen may be unchanged or slightly enlarged.

miR-145-5p Inhibits Vascular Smooth Muscle Cells (VSMCs) Proliferation and Migration by Dysregulating the Transforming Growth Factor-b Signaling Cascade.

BACKGROUND There is accumulating evidence demonstrating that microRNAs (miRNA) play essential roles in proliferation, migration, and invasion of vascular smooth muscle cells (VSMCs). However, the exact function of these molecules and the mechanisms involved are not fully understood. In this study, we defined the role of miR-145-5p in VSMCs. MATERIAL AND METHODS This study used the PDGF-bb-induced VSMCs proliferation model. Expression of miR-145-5p and its target, Smad4, were detected and measured by real-time PCR and Western blot analysis. The luciferase reporter of miR-145-5p was used to elucidate miRNA-target interactions. The functions of miR-145-5p in proliferation and migration were detected by CCK-8 assay, Transwell assay, and scratch test. RESULTS This study demonstrates that miR-145-5p is downregulated in PDGF-mediated VSMCs in both time- and dose-dependent manners. The in vitro results suggest that overexpression of miR-145-5p results in a reduction in SMAD4 and an increase in SMAD2, Smad3, and TGF-ß at the mRNA and protein levels. Overexpression of miR-145-5p inhibited PDGF-induced VSMCs proliferation and migration. Moreover, SMAD4 was identified as a direct target of miR-145-5p and is involved in PDGF-mediated VSMC proliferation. Downstream factors such as Smad2, Smad3, and TGF-ß were also influenced by miR-145-5p. CONCLUSIONS We identify miR-145-5p as a novel regulator of VSMC. Moreover, miR-145-5p inhibits VSMCs proliferation and migration by directly targeting Smad4 and dysregulating the transforming growth factor-ß signaling cascade, including Smad2, Smad3, and TGF-ß.

Evaluation of a High Concentrated Contrast Media Injection Protocol in Combination with Low Tube Current for Dose Reduction in Coronary Computed Tomography Angiography: A Randomized, Two-center Prospective Study.

RATIONALE AND OBJECTIVES: The study aimed to prospectively evaluate the radiation dose reduction potential and image quality (IQ) of a high-concentration contrast media (HCCM) injection protocol in combination with a low tube current (mAs) in coronary computed tomography angiography. MATERIALS AND METHODS: Eighty-one consecutive patients (mean age: 62 years; 34 females; body mass index: 18-31) were included and randomized-assigned into two groups. All computed tomography (CT) examinations were performed in two groups with the same tube voltage (100 kV), flow rate of contrast medium (5.0 mL/s), and iodine dose (22.8 g). An automatic mAs and low concentration contrast medium (300 mgI/mL) were used in group A, whereas effective mAs was reduced by a factor 0.6 along with HCCM (400 mgI/mL) in group B. Radiation dose was assessed (CT dose index [CTDIvol] and dose length product), and vessel-based objective IQ for various regions of interest (enhancement, noise, signal-to-noise ratio, and contrast-to-noise ratio), subjective IQ, noise, and motion artifacts were analyzed overall and vessel-based with a 5-point Likert scale. RESULTS: The CT attenuation of coronary arteries and image noise in group B were significantly higher than those in group A (ranges: 507.5-548.1 Hounsfield units vs 407.5-444.5 Hounsfield units; and 20.3 ± 8.6 vs 17.7 ± 8.0) (P ≤ 0.0166). There was no significant difference between the two groups in signal-to-noise ratio, contrast-to-noise ratio, and subjective IQ of coronary arteries (29.4-31.7, 30.0-37.0, and medium score of 5 in group A vs 29.4-32.4, 27.7-36.3, and medium score of 5 in group B, respectively, P ≥ 0.1859). Both mean CTDIvol and dose length product in group B were 58% of those of group A. CONCLUSIONS: HCCM combined with low tube current allows dose reduction in coronary computed tomography angiography and does not compromise IQ.

Atorvastatin antagonizes the visfatin-induced expression of inflammatory mediators via the upregulation of NF-κB activation in HCAECs.

The present study investigated whether atorvastatin antagonizes the visfatin-induced expression of inflammatory mediators in human coronary artery endothelial cells (HCAECs). Several analysis methods, such as reverse transcription-quantitative polymerase chain reaction, western blot analysis and H2DCFDA incubation, were used in the present study. The data showed that atorvastatin decreased the visfatin-induced expression of interleukin (IL)-6 and IL-8 in HCAECs. In addition, atorvastatin inhibited the visfatin-induced expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in HCAECs. In addition, the present study found that atorvastatin inhibited the visfatin-activated nuclear factor-κB (NF-κB) signal pathway by preventing extracellular signal-regulated kinase phosphorylation in HCAECs. Atorvastatin significantly inhibited visfatin-induced NF-κB activity via the upregulation of reactive oxygen species production. Atorvastatin, a visfatin antagonist (FK866) and an NF-κB inhibitor (BAY11-7082) decreased the visfatin-induced expression of inflammatory mediators via the upregulation of NF-κB activation in HCAECs. These results suggest that atorvastatin may inhibit the visfatin-induced upregulation of inflammatory mediators through blocking the NF-κB signal pathway. The findings of the present study provide a potential use for atorvastatin and visfatin in the pathogenesis of HCAEC dysfunction. This knowledge may contribute to the development of novel therapies for atherosclerosis.

Low-dose volume perfusion computed tomography (VPCT) for diagnosis of solitary pulmonary nodules.

OBJECTIVE: To characterize solitary pulmonary nodules (SPN) in terms of perfusion parameters using low-dose volume perfusion computed tomography (VPCT) and two different calculation methods, compare their results, look for interobserver agreement of measurements and investigate the feasibility of low-dose VPCT. MATERIALS AND METHODS: This study was approved by the local Institutional Review Board and all patients provided written informed consent. Seventy-one patients (mean age 60.8 years ±9.6) with solitary pulmonary nodules were enrolled. Low-dose VPCT was performed for 38.63s covering the involved lung (70kV, 120mAs, 22 consecutive volume measurements, 50mL iodinated contrast, flow rate 4mL/s). Mean blood flow (BF), blood volume (BV) and k-trans were determined both with the maximum slope+Patlak vs. deconvolution method. Additionally, the difference of VPCT parameters between different type lesions and normal tissue was analyzed. Interobserver agreement for all perfusion parameters was calculated using intraclass correlation coefficients (ICC). The effective radiation dose of the VPCT and the total CT scan protocol were recorded. All CT findings were histologically confirmed by surgical intervention. RESULTS: The mean lesion size was 18.6mm. Interobserver agreement measure with ICC shows high agreement between the measurements (κ=0.85). The effective radiation dose of the VPCT was 9.3mSv. The mean perfusion values for BF, BV and k-trans of 120.6mL/100g tissue/', 11.6mL/100g tissue/', and 18.5mL/100g tissue/' for the deconvolution method, and 50.1mL/100g tissue/', 11.6mL/100g tissue/' and 24.3mL/100g tissue/' for the maximum slope+Patlak method, which were significantly higher than those of normal muscle (20.7mL/100g tissue/', 2.6mL/100g tissue/', and 7.6mL/100g tissue/' for the deconvolution method and 10.9mL/100g tissue/', 3.1mL/100g tissue/' and 8.1mL/100g tissue/' for the maximum slope method). The best overall correlation between calculation methods was achieved for measurements of BF. CONCLUSION: The low-dose volume perfusion CT of the solitary pulmonary nodules can effectively reduce the radiation dose and non-invasively assess perfusion of SPN within the entire lesion volume.

Diagnosis of Dissection of the Coronary Artery Dissection by Multidetector Computed Tomography: A Comparative Study With Coronary Angiology.

OBJECTIVES: This study was to assess the diagnostic performance of multidetector computed tomography (MDCT) angiographic protocol for dissection of the coronary artery (DCA) detection compared with coronary angiology (CAG). METHODS: Intravascular ultrasound was used as the gold standard for DCA diagnosis. Thirty-six DCA patients and 34 non-DCA (control) participants were retrospectively reviewed. The CAG and MDCT angiography images were separately reviewed by 4 independent observers, and a 5-point grading scale was used for DCA diagnosis. Diagnostic performance was compared using receiver operating characteristic analysis. Sensitivity, specificity, and negative predictive values were calculated. RESULTS: The MDCT performed significantly better than that of CAG (AZ = 0.9943 ± 0.0034 vs AZ = 0.8411 ± 0.0274, respectively) for DCA detection. The sensitivity (98.6%), specificity (89.7%), and negative predictive value (98.4%) of MDCT for DCA were higher than those of CAG (77.8%, 79.4%, and 77.1%, respectively). CONCLUSIONS: Multidetector computed tomography angiography was a more sensitive and specific technique for the diagnosis of DCA compared with CAG.

Comparison of adaptive statistical iterative and filtered back projection reconstruction techniques in brain CT.

PURPOSE: To compare image quality and visualization of normal structures and lesions in brain computed tomography (CT) with adaptive statistical iterative reconstruction (ASIR) and filtered back projection (FBP) reconstruction techniques in different X-ray tube current-time products. MATERIALS AND METHODS: In this IRB-approved prospective study, forty patients (nineteen men, twenty-one women; mean age 69.5 ± 11.2 years) received brain scan at different tube current-time products (300 and 200 mAs) in 64-section multi-detector CT (GE, Discovery CT750 HD). Images were reconstructed with FBP and four levels of ASIR-FBP blending. Two radiologists (please note that our hospital is renowned for its geriatric medicine department, and these two radiologists are more experienced in chronic cerebral vascular disease than in neoplastic disease, so this research did not contain cerebral tumors but as a discussion) assessed all the reconstructed images for visibility of normal structures, lesion conspicuity, image contrast and diagnostic confidence in a blinded and randomized manner. Volume CT dose index (CTDI(vol)) and dose-length product (DLP) were recorded. All the data were analyzed by using SPSS 13.0 statistical analysis software. RESULTS: There was no statistically significant difference between the image qualities at 200 mAs with 50% ASIR blending technique and 300 mAs with FBP technique (p>.05). While between the image qualities at 200 mAs with FBP and 300 mAs with FBP technique a statistically significant difference (p<.05) was found. CONCLUSION: ASIR provided same image quality and diagnostic ability in brain imaging with greater than 30% dose reduction compared with FBP reconstruction technique.

[Correlation between the lung pixel indexes of multi-slice spiral CT and pulmonary function test].

OBJECTIVE: To study the correlation between the lung pixel indexes of multi-slice spiral CT (MSCT) and pulmonary function test (PFT), and to explore the CT features of histograms of lung attenuation. METHODS: MSCT scan and pulmonary function test (PFT) were separately performed in 127 subjects within one week. The total lung was scanned with MSCT at full inspiration, full expiration, and normal respiration. The lung pixel indexes were measured by Pulmo pulmonary quantitative software. These indexes include PI(-910Huin), PI(-960HUEX), PI(-910Huin), PI(-960Huex), PI(-910(Hun), PI(-960Hun), PI(910Huex/in), and the histograms of lung attenuation. RESULTS: Correlation existed between all the lung pixel indexes of MSCT and PFT. PI(-910Huex/in showed the best correlation with FEV1/FVC (r = 0.901, P < 0.01). Three distribution patterns were found in the histograms of lung attenuation of total lung, including double-peak distribution (n = 28), similar normal distribution (n = 81), and partial distribution (n = 18). CONCLUSION: The lung pixel indexes of MSCT have significant correlation with PFT and can be used to assess the pulmonary function.