An assessment system for clinical and biological interpretability in ulcerative colitis.

Ulcerative colitis (UC) is a serious inflammatory bowel disease (IBD) with high morbidity and mortality worldwide. As the traditional diagnostic techniques have various limitations in the practice and diagnosis of early ulcerative colitis, it is necessary to develop new diagnostic models from molecular biology to supplement the existing methods. In this study, we developed a machine learning-based synthesis to construct an artificial intelligence diagnostic model for ulcerative colitis, and the correctness of the model is verified using an external independent dataset. According to the significantly expressed genes related to the occurrence of UC in the model, an unsupervised quantitative ulcerative colitis related score (UCRScore) based on principal coordinate analysis was established. The UCRScore is not only highly generalizable across UC bulk cohorts at different stages, but also highly generalizable across single-cell datasets, with the same effect in terms of cell numbers, activation pathways and mechanisms. As an important role of screening genes in disease occurrence, based on connectivity map analysis, 5 potential targeting molecular compounds were identified, which can be used as an additional supplement to the therapeutic of UC. Overall, this study provides a potential tool for differential diagnosis and assessment of bio-pathological changes in UC at the macroscopic level, providing an opportunity to optimize the diagnosis and treatment of UC.

Consensus report from the 10th Global Forum for Liver Magnetic Resonance Imaging: developments in HCC management.

The 10th Global Forum for Liver Magnetic Resonance Imaging (MRI) was held as a virtual 2-day meeting in October 2021, attended by delegates from North and South America, Asia, Australia, and Europe. Most delegates were radiologists with experience in liver MRI, with representation also from specialists in liver surgery, oncology, and hepatology. Presentations, discussions, and working groups at the Forum focused on the following themes: • Gadoxetic acid in clinical practice: Eastern and Western perspectives on current uses and challenges in hepatocellular carcinoma (HCC) screening/surveillance, diagnosis, and management • Economics and outcomes of HCC imaging • Radiomics, artificial intelligence (AI) and deep learning (DL) applications of MRI in HCC. These themes are the subject of the current manuscript. A second manuscript discusses multidisciplinary tumor board perspectives: how to approach early-, mid-, and late-stage HCC management from the perspectives of a liver surgeon, interventional radiologist, and oncologist (Taouli et al, 2023). Delegates voted on consensus statements that were developed by working groups on these meeting themes. A consensus was considered to be reached if at least 80% of the voting delegates agreed on the statements. CLINICAL RELEVANCE STATEMENT: This review highlights the clinical applications of gadoxetic acid-enhanced MRI for liver cancer screening and diagnosis, as well as its cost-effectiveness and the applications of radiomics and AI in patients with liver cancer. KEY POINTS: • Interpretation of gadoxetic acid-enhanced MRI differs slightly between Eastern and Western guidelines, reflecting different regional requirements for sensitivity vs specificity. • Emerging data are encouraging for the cost-effectiveness of gadoxetic acid-enhanced MRI in HCC screening and diagnosis, but more studies are required. • Radiomics and artificial intelligence are likely, in the future, to contribute to the detection, staging, assessment of treatment response and prediction of prognosis of HCC-reducing the burden on radiologists and other specialists and supporting timely and targeted treatment for patients.

MRI whole-lesion texture analysis on ADC maps for the prognostic assessment of ischemic stroke.

BACKGROUND: This study aims is to explore whether it is feasible to use magnetic resonance texture analysis (MRTA) in order to distinguish favorable from unfavorable function outcomes and determine the prognostic factors associated with favorable outcomes of stroke. METHODS: The retrospective study included 103 consecutive patients who confirmed unilateral anterior circulation subacute ischemic stroke by computed tomography angiography between January 2018 and September 2019. Patients were divided into favorable outcome (modified Rankin scale, mRS ≤ 2) and unfavorable outcome (mRS > 2) groups according to mRS scores at day 90. Two radiologists manually segmented the infarction lesions based on diffusion-weighted imaging and transferred the images to corresponding apparent diffusion coefficient (ADC) maps in order to extract texture features. The prediction models including clinical characteristics and texture features were built using multiple logistic regression. A univariate analysis was conducted to assess the performance of the mean ADC value of the infarction lesion. A Delong's test was used to compare the predictive performance of models through the receiver operating characteristic curve. RESULTS: The mean ADC performance was moderate [AUC = 0.60, 95% confidence interval (CI) 0.49-0.71]. The texture feature model of the ADC map (tADC), contained seven texture features, and presented good prediction performance (AUC = 0.83, 95%CI 0.75-0.91). The energy obtained after wavelet transform, and the kurtosis and skewness obtained after Laplacian of Gaussian transformation were identified as independent prognostic factors for the favorable stroke outcomes. In addition, the combination of the tADC model and clinical characteristics (hypertension, diabetes mellitus, smoking, and atrial fibrillation) exhibited a subtly better performance (AUC = 0.86, 95%CI 0.79-0.93; P > 0.05, Delong's). CONCLUSION: The models based on MRTA on ADC maps are useful to evaluate the clinical function outcomes in patients with unilateral anterior circulation ischemic stroke. Energy obtained after wavelet transform, kurtosis obtained after Laplacian of Gaussian transform, and skewness obtained after Laplacian of Gaussian transform were identified as independent prognostic factors for favorable stroke outcomes.

Biparametric magnetic resonance imaging assessment for detection of muscle-invasive bladder cancer: a systematic review and meta-analysis.

OBJECTIVES: To investigate if removing DCE from the Vesical Imaging Reporting and Data System (VI-RADS) influences the diagnostic accuracy of muscle-invasive bladder cancer (MIBC). We also explored using different reference standards on the MRI diagnostic performance. METHODS: We searched the Cochrane Library, Embase, and PubMed databases to June 26, 2021. Pooled biparametric MRI (bpMRI, T2WI+DWI) and multiparametric MRI (mpMRI, T2WI+DWI+DCE) sensitivities and specificities and the diagnostic performances of these methods for MIBC were compared using different reference standards. RESULTS: Seventeen studies with 2344 patients were finally included, of which 7 studies, including 1041 patients, reported the diagnostic performance of bpMRI. VI-RADS showed sensitivities and specificities of 0.91 (95% CI 0.87-0.94) and 0.86 (95% CI 0.77-0.91) at cutoff scores of 3, and 0.85 (95% CI 0.77-0.90) and 0.93 (95% CI 0.89-0.96) at cutoff scores of 4. BpMRI showed sensitivities and specificities of 0.90 (95% CI 0.69-0.97) and 0.90 (95% CI 0.81-0.95), and 0.84 (95% CI 0.78-0.88) and 0.97 (95% CI 0.87-0.99), respectively, for cutoff scores of 3 and 4. The sensitivities of bpMRI vs mpMRI for MIBC were not significantly different, but bpMRI was more specific than mpMRI at cutoff scores of 3 (p = 0.02) and 4 (p = 0.02). The VI-RADS studies using primary transurethral resection of bladder tumors (TURBT) as the reference standard had significantly higher sensitivities (p < 0.001) than those using secondary TURBT or radical cystectomy as the reference. DATA CONCLUSION: BpMRI and conventional VI-RADS had similar diagnostic efficacies for MIBC. Since MRI overestimated MIBC diagnoses using primary TURBT as the reference standard, we recommend using secondary TURBT as the reference standard. KEY POINTS: • Biparametric MRI without DCE had similar diagnostic efficacies for MIBC compared with conventional VI-RADS. • The sensitivity of VI-RADS was overestimated when referring to the primary TURBT results. • Biparametric MRI comprised of T2WI and DWI could be used for detecting MIBC in clinical practice.

SARS-CoV-2 and the reproductive system: assessment of risk and recommendations for infection control in reproductive departments.

The World Health Organization has declared the outbreak of the coronavirus disease COVID-19, caused by SARS-CoV-2, a pandemic. This novel infectious disease has rapidly become a global health threat. Currently, there are limited data on the extent of reproductive system damage caused by COVID-19. We reviewed the potential risks for complications in the reproductive system caused by COVID-19 infection. In addition, based on the latest American Society for Reproductive Medicine (ASRM), and European Society of Human Reproduction and Embryology (ESHRE), recommendations regarding clinical and patient management, we provide a series of suggestions for infection control measures in reproductive medicine departments. With the gradual restoration of reproductive care services, reproductive departments in epidemic areas should actively seek to minimize COVID-19 infection of both healthcare workers and patients.

Texture analysis based on ADC maps and T2-FLAIR images for the assessment of the severity and prognosis of ischaemic stroke.

OBJECTIVES: To explore the feasibility of texture analysis based on T2-weighted fluid-attenuated inversion recovery (T2-FLAIR) images and apparent diffusion coefficient (ADC) maps in the assessment of the severity and prognosis of ischaemic stroke using the National Institutes of Health Stroke Scale (NIHSS) and modified Rankin scale (mRS) scores, respectively. METHODS: Overall, 116 patients diagnosed with subacute ischaemic stroke were included in this retrospective study. Based on T2-FLAIR images and ADC maps, 15 texture features were extracted from the ROIs of each patient using grey-level co-occurrence matrix (GLCM) and local binary pattern histogram Fourier (LBP-HF) methods. The correlations of NIHSS score on admission (NIHSSbaseline), NIHSS score 24 h after stroke onset (NIHSS24h) and mRS score with the texture features were evaluated using Spearman's partial correlations. The receiver operating characteristic (ROC) curve was used to compare the performance of the selected texture features in the evaluation of stroke severity and prognosis. RESULTS: Texture features derived from the T2-FLAIR images and ADC maps were correlated with NIHSS score and mRS score. EntropyADC and 0.75QuantileT2-FLAIR showed the best diagnostic performance for assessing stroke severity. The combination of EntropyADC and 0.75QuantileT2-FLAIR achieved a better performance in the evaluation of stroke severity (AUC = 0.7, p = 0.01) than either feature alone. Only 0.05QuantileT2-FLAIR was found to be correlated with mRS score, and none of the texture features were predictive of mRS score. CONCLUSION: Texture features derived from T2-FLAIR images and ADC maps might serve as biomarkers to evaluate stroke severity, but were insufficient to predict stroke prognosis.

Elastography for Longitudinal Assessment of Liver Fibrosis after Antiviral Therapy: A Review.

Chronic hepatitis B or C viral infection is a common cause of liver cirrhosis and hepatocellular carcinoma. Fibrosis regression can be achieved after long-term antiviral therapy (AVT). Monitoring of dynamic changes in liver fibrosis after treatment is essential for establishing prognosis and formulation of a follow-up surveillance program. Routine surveillance of fibrosis after AVT by liver biopsy, the gold standard for fibrosis assessment, is hindered by its invasive nature, sampling error and observer variability. Elastography is a noninvasive quantitative alternative that has been widely used and validated for the staging of liver fibrosis prior to treatment. Recently, increasing research interest has been focused on the role of elastography in longitudinal assessment of liver fibrosis after AVT. In this review, the basic principles, acquisition techniques, diagnostic performances, and strengths and limitations of ultrasound elastography and magnetic resonance elastography are presented. Emerging evidence regarding the use of elastography techniques for the monitoring of liver fibrosis after AVT is summarized. Current challenges and future directions are also discussed, designed to optimize the application of these techniques in clinical practice.

Computed Tomographic Portography with Esophageal Variceal Measurements in the Evaluation of Esophageal Variceal Severity and Assessment of Esophageal Variceal Volume Efficacy.

RATIONALE AND OBJECTIVES: The aim of our study is to evaluate the severity of esophageal varices (EV), based on the computed tomographic portography (CTP) measurement of EV in the distal esophagus and to assess the prediction value of EV volume. PATIENTS AND METHODS: A total of 53 EV patients examined by CTP within 4 weeks of upper endoscopy were evaluated, the patients were divided into a nonconspicuous EV group (mild-to-moderate EV, n = 28) and a conspicuous EV group (severe EV, n = 25) according to endoscopy results. The diameter, cross-sectional surface area (CSA), and volume of EV were measured independently using 3D-slicer (Boston) by two experienced abdominal radiologists blinded to endoscopy findings. The averaged values measured by the two observers were used in the final dataset, these indicators' predictive performances were studied by using receiver operating characteristic curve analysis, and the area under the curve (Az) and the cutoff values were calculated to distinguish mild-to-moderate from severe EV. RESULTS: The Az values of volume, diameter and CSA in differentiating severe EV were 0.817, 0.794, and 0.784 for observer-1, corresponding values for observer-2 were 0.796, 0.774, and 0.707, there was almost perfect interobserver agreement for all measurements. All indices were larger in the conspicuous group than the nonconspicuous group in both observers (p ≤ 0.01). In the final dataset, application of a 654.0-mm3-volume criterion yielded sensitivity, specificity of 96%, 50%, application of a 5.2-mm-diameter criterion yielded sensitivity, specificity of 80%, 75%, and application of a 68.6-mm2-CSA criterion yielded sensitivity, specificity of 52%, 93%. CONCLUSION: The volume of EV could be used as a new effective indictor for evaluating EV, and use of volume, diameter, and CSA of EV based on CTP allows discrimination between mild-to-moderate and severe EV in cirrhotic patients.

Role of medical imaging for immune checkpoint blockade therapy: From response assessment to prognosis prediction.

Immune checkpoint blockade (ICB) represents a promising approach in cancer therapy. Owing to the peculiar biologic mechanisms of anticancer activity, checkpoint blockers are accompanied with distinctive response patterns and toxicity profiles. Medical imaging is the cornerstone for response assessment to immunotherapy and plays a critical role in monitoring of immune-related adverse events (irAEs). Imaging-based biomarkers have shown tremendous potential for the prediction of therapeutic efficacies and clinical outcomes in patients treated with checkpoint inhibitors. In this article, the landscape of current response assessment systems for immunotherapy was reviewed with a special focus on the latest advances in the assessment of responses to ICB. Emerging imaging biomarkers were discussed along with the challenges regarding their clinical transformation. In addition, the biological mechanisms and clinical applications of ICB and irAEs were also within the scope of this review.

3D Multi-Echo Dixon technique for simultaneous assessment of liver steatosis and iron overload in patients with chronic liver diseases: a feasibility study.

BACKGROUND: Patients with chronic liver diseases (CLDs) often suffer from lipidosis or siderosis. Proton density fat fraction (PDFF) and R2* can be used as quantitative parameters to assess the fat/iron content of the liver. The aim of this study was to evaluate the influence of liver fibrosis and inflammation on the 3D Multi-echo Dixon (3D ME Dixon) parameters (MRI-PDFF and R2*) in patients with CLDs and to determine the feasibility of 3D ME Dixon technique for the simultaneous assessment of liver steatosis and iron overload using histopathologic findings as the reference standard. METHODS: Ninety-nine consecutive patients with CLDs underwent T1-independent, T2*-corrected 3D ME Dixon sequence with reconstruction using multipeak spectral modeling on a 3T MR scanner. Liver specimen was reviewed in all cases, grading liver steatosis, siderosis, fibrosis, and inflammation. Spearman correlation analysis was performed to determine the relationship between 3D ME Dixon parameters (MRI-PDFF and R2*) and histopathological and biochemical features [liver steatosis, iron overload, liver fibrosis, inflammation, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL)]. Multiple regression analysis was applied to identify variables associated with 3D ME Dixon parameters. Receiver operating characteristic (ROC) analysis was performed to determine the diagnostic performance of these parameters to differentiate liver steatosis or iron overload. RESULTS: In multivariate analysis, only liver steatosis independently influenced PDFF values (R2=0.803, P<0.001), liver iron overload and fibrosis influenced R2* values (R2=0.647, P<0.001). The Spearman analyses showed that R2* values were moderately correlated with fibrosis stages (r=0.542, P<0.001) in the subgroup with the absence of iron overload. The area under the ROC curve of PDFF was 0.989 for the diagnosis of steatosis grade 1 or greater, and 0.986 for steatosis grade 2 or greater. The area under the ROC curve of R2* was 0.815 for identifying iron overload grade 1 or greater, and 0.876 for iron overload grade 2 or greater. CONCLUSIONS: 3D Multi-Echo Dixon can be used to simultaneously evaluate liver steatosis and iron overload in patients with CLDs, especially for quantification of liver steatosis. However, liver R2* value may be affected by the liver fibrosis in the setting of CLDs with absence of iron overload.

IVIM improves preoperative assessment of microvascular invasion in HCC.

PURPOSE: To prospectively evaluate the potential role of intravoxel incoherent motion (IVIM) and conventional radiologic features for preoperative prediction of microvascular invasion (MVI) in patients with hepatocellular carcinoma (HCC). METHODS: Institutional review board approval and written informed consent were obtained for this study. A cohort comprising 115 patients with 135 newly diagnosed HCCs between January 2016 and April 2017 were evaluated. Two radiologists independently reviewed the radiologic features and the apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudodiffusion coefficient (D*), and pseudodiffusion component fraction (f) were also measured. Interobserver agreement was checked and univariate and multivariate logistic regressions were used for screening the risk factors. Receiver operating characteristics (ROC) curve analyses were performed to evaluate the diagnostic performance. RESULTS: Features significantly related to MVI of HCC at univariate analysis were reduced ADC (odds ratio, 0.341; 95% CI, 0.211-0.552; p < 0.001), D (odds ratio, 0.141; 95% CI, 0.067-0.299; p < 0.001), and irregular circumferential enhancement (odds ratio, 9.908; 95% CI, 3.776-25.996; p < 0.001). At multivariate analysis, only D value (odds ratio, 0.096; 95% CI, 0.025-0.364; p < 0.001) was the independent risk factor for MVI of HCC. The mean D value for MVI of HCC showed an area under ROC curves of 0.815 (95% CI, 0.740-0.877). CONCLUSION: IVIM model-derived D value is superior to ADC measured with mono-exponential model for evaluating the MVI of HCC. Among MR imaging features, tumor margin, enhancement pattern, tumor capsule, and peritumoral enhancement were not predictive for MVI. KEY POINTS: • Diffusion MRI is useful for non-invasively evaluating the microvascular invasion of hepatocellular carcinoma. • IVIM model is advantageous over mono-exponential model for assessing the microvascular invasion of hepatocellular carcinoma. • Decreased D value was the independent risk factor for predicting MVI of HCC.

Intravoxel incoherent motion diffusion-weighted imaging for assessment of histologic grade of hepatocellular carcinoma: comparison of three methods for positioning region of interest.

OBJECTIVES: To prospectively compare the diagnostic performances of three methods of region of interest (ROI) placement for the measurements of intravoxel incoherent motion (IVIM) diffusion-weighted MR imaging in differentiating the histologic grade of hepatocellular carcinoma (HCC). METHODS: Eighty-seven patients with 91 newly diagnosed HCCs were studied using IVIM imaging. Two attending radiologists separately identified the selection of tumour tissue for ROI positioning. Three different ROI positioning methods, namely the whole tumour volume (WTV) method, three-ROI method and one-section method, were used for the measurement. Kruskal-Wallis rank test or one-way ANOVA was used to compare the difference in IVIM parameters and ADC across the three different ROI positioning methods. Spearman correlation analysis was used to determine the correlation between each parameter and Edmondson-Steiner (E-S) grade. Receiver operating characteristics (ROC) curve analyses were performed to evaluate the diagnostic performance. RESULTS: For the ADC and ADCslow, the mean value measured by using the WTV method was significant higher than the one-section and three-ROI methods (all p < 0.01). For the ADCslow, the highest area under curve (AUC) with a value of 0.969 was obtained by using the WTV method, followed by the one-section method (AUC = 0.938) and three-ROI method (AUC = 0.873). Additionally, for the ADC, AUC values were 0.861 for WTV method, 0.840 for one-section method and 0.806 for three-ROI method. CONCLUSIONS: Different ROI positioning methods used significantly affect the IVIM parameters and ADC measurements. Measurements of ADCslow value derived from WTV method entailed the highest diagnostic performance in grading HCC. KEY POINTS: • Diffusion MRI is useful for non-invasively differentiating the histologic grade of hepatocellular carcinoma. • Different ROI positioning methods used significantly affect the IVIM parameters and ADC measurements. • IVIM model is advantageous over mono-exponential model for assessing the histologic grade of hepatocellular carcinoma.

2D/3D CMR tissue tracking versus CMR tagging in the assessment of spontaneous T2DM rhesus monkeys with isolated diastolic dysfunction.

BACKGROUND: Spontaneous T2DM in rhesus monkeys manifests as isolated diastolic dysfunction in the early stage of diabetic cardiomyopathy, similar to humans. Myocardial deformation measurements have emerged as a superior way to measure left ventricular (LV) function in the early stage of cardiac dysfunction, making it possible to further evaluate early-stage LV dysfunction in spontaneous T2DM rhesus monkeys. METHODS: Spontaneous T2DM rhesus monkeys with isolated diastolic dysfunction (T2DM-DD, n = 10) and corresponding nondiabetic healthy animals (ND, n = 9) were prospectively scanned for a CMR study. Circumferential and longitudinal peak systolic strain (Ecc, Ell), time to peak strain (tEcc, tEll) and peak diastolic strain rate (CSR, LSR) obtained from 2D/3D CMR-TT were compared with those obtained from CMR tagging separately. In addition, all CMR imaging protocols were performed twice in 9 ND animals to assess test-retest reproducibility. RESULTS: Compared with the ND group, the T2DM-DD monkeys demonstrated significantly impaired LV Ecc (- 10.63 ± 3.23 vs - 14.18 ± 3.19, p < 0.05), CSR (65.50 ± 14.48 vs 65.50 ± 14.48, p < 0.01), Ell (- 9.11 ± 2.59 vs - 14.17 ± 1.68, p < 0.05), and LSR (59.43 ± 19.17 vs 108.46 ± 22.33, p < 0.01) with the tagging. Only Ecc (- 13.10 ± 2.47 vs - 19.03 ± 3.69, p < 0.01) and CSR (148.90 ± 31.27 vs 202.00 ± 51.88, p < 0.01) were significantly reduced with 2D CMR-TT, and only Ecc (- 13.77 ± 1.98 vs - 17.26 ± 3.78, p < 0.05) was significantly reduced with 3D CMR-TT. Moreover, 2D/3D CMR-TT-derived Ecc and CSR correlated with the corresponding tagging values collectively, with a statistically significant ICC value (p < 0.05). Test-retest repeatability analysis showed that most tagging-derived biomarkers had acceptable repeatability (p < 0.01). In addition, 2D CMR-TT-derived indicators were poorer than those derived from the tagging method but better than those obtained using the 3D method, with larger ICCs except for tEcc (p < 0.05). CONCLUSIONS: LV systolic and diastolic deformations were impaired in spontaneous T2DM rhesus monkeys previously diagnosed with isolated diastolic dysfunction by echocardiography. The 2D CMR-TT-derived Ecc and CSR were effective in the evaluation of the myocardial systolic and diastolic functions of early-diabetic cardiomyopathy, with relatively higher test-retest reproducibility and acceptable correlation with the tagging method compared with the 3D CMR-TT method.

Chromosome-level assembly, genetic and physical mapping of Phalaenopsis aphrodite genome provides new insights into species adaptation and resources for orchid breeding.

The Orchidaceae is a diverse and ecologically important plant family. Approximately 69% of all orchid species are epiphytes, which provide diverse microhabitats for many small animals and fungi in the canopy of tropical rainforests. Moreover, many orchids are of economic importance as food flavourings or ornamental plants. Phalaenopsis aphrodite, an epiphytic orchid, is a major breeding parent of many commercial orchid hybrids. We provide a high-quality chromosome-scale assembly of the P. aphrodite genome. The total length of all scaffolds is 1025.1 Mb, with N50 scaffold size of 19.7 Mb. A total of 28 902 protein-coding genes were identified. We constructed an orchid genetic linkage map, and then anchored and ordered the genomic scaffolds along the linkage groups. We also established a high-resolution pachytene karyotype of P. aphrodite and completed the assignment of linkage groups to the 19 chromosomes using fluorescence in situ hybridization. We identified an expansion in the epiphytic orchid lineage of FRS5-like subclade associated with adaptations to the life in the canopy. Phylogenetic analysis further provides new insights into the orchid lineage-specific duplications of MADS-box genes, which might have contributed to the variation in labellum and pollinium morphology and its accessory structure. To our knowledge, this is the first orchid genome to be integrated with a SNP-based genetic linkage map and validated by physical mapping. The genome and genetic map not only offer unprecedented resources for increasing breeding efficiency in horticultural orchids but also provide an important foundation for future studies in adaptation genomics of epiphytes.

Quantification of pancreatic fat with dual-echo imaging at 3.0-T MR in clinical application: how do the corrections for T1 and T2* relaxation effect work and simplified correction strategy.

Background Dual-echo imaging is a routine clinical magnetic resonance (MR) sequence affected by T1 and T2* relaxation effect in fat quantification. The separate impacts of T1 and T2* relaxation effect in pancreatic fat quantification using dual-echo imaging at 3.0-T MR have not been reported in detail. Purpose To demonstrate the separate T1 and T2* relaxation effect on pancreatic fat quantification by dual-echo imaging at 3.0-T MR and the simplified correction strategy is discussed for convenient clinical application. Material and Methods Twenty-one non-alcoholic fatty liver disease (NAFLD) participants with high risk of pancreatic steatosis were included. Pancreatic fat fractions (FF) by dual-echo imaging with different corrections were compared to that of proton magnetic resonance spectroscopy (1H-MRS). Correlation analysis and Bland-Altman analysis were applied. Results The FF by 1H-MRS was 5.9 ± 1.7%. Significant positive correlation (all P < 0.01) was found between FF by 1H-MRS and each dual-echo imaging, in which T1 and T2* correction showed the best correlation (r = 0.95, FF = 6.2 ± 1.7%) and no correction showed the worst correlation (r = 0.86, FF = 5.2 ± 2.0%), and the simplified T1 and T2* correction manifested as r = 0.93 and FF = 6.3 ± 1.8%. FF by T1 and T2* correction showed the best agreement, while T1 correction showed the worst agreement as compared to that of 1H-MRS. Conclusion T1 and T2* correction shows the best performance while no correction dual-echo imaging remains clinical available which may benefit from prior OP echo. Simplified correction using single T2* (32.6 ms) of water and fat is recommended for convenient clinical application in absence of obvious pancreatic iron overload.

Qualitative and Quantitative Assessment of Abdominal and Pelvic CT Image Quality Using Iopromide With Different Concentrations of Iodine (300 and 370 mg I/mL).

OBJECTIVE: The purpose of this study was to analyze the quality of MDCT images obtained using iopromide with two different concentrations of iodine (300 and 370 mg I/mL) in daily clinical settings. SUBJECTS AND METHODS: Patients from 38 hospitals in China undergoing abdominal or pelvic CT with iopromide were prospectively recruited. MDCT was performed using iopromide with an iodine concentration of 300 or 370 mg I/mL. CT quality image was graded as excellent, good, adequate, and poor. Objective indicators were the contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR). Outcomes were compared according to organ studied, tumor type (benign vs malignant), saline usage, and type of MDCT (16-MDCT vs 64-MDCT). RESULTS: A total of 4506 patients (63.7% men) with a mean (± SD) age of 56.3 ± 14.1 years and mean body mass index (weight in kilograms divided by the square of height in meters) of 23.2 ± 3.3 were included. Iopromide with 300 mg I/mL was used for 3042 patients (67.5%), and 370 mg I/mL was used for 1464 patients (32.2%). A total of 1847 scans (41.0%) had excellent image quality, 2454 (54.5%) had good quality, 176 (3.9%) had adequate quality, and 29 (0.6%) had poor quality. No differences were noted between CT scans that did or did not use saline, 16-MDCT versus 64-MDCT scans, and 300 versus 370 mg I/mL iopromide. Variations in the CNR and SNR were noted between the two iodine concentrations with respect to other parameters examined. CONCLUSION: Iopromide with both concentrations of iodine provided acceptable image quality, though according to CNR and SNR, one or the other may provide better quality in different situations.

Exposure of the murine RAW 264.7 macrophage cell line to dicalcium silicate coating: assessment of cytotoxicity and pro-inflammatory effects.

Inflammatory effects are significant elements of the immune response to biomaterials. Previously, we reported inflammatory effects in response to dicalcium silicate (Ca2SiO4, C2S) particles. However, the immunological effects of C2S coatings have not been studied. C2S often used as coatings materials in orthopedic and dentistry applications. It may have different effect from C2S particles. Further, it remains unclear whether C2S coating is equally biocompatible as 45S5 coating. The aim of this study was to test the cytotoxicity and pro-inflammatory effects of C2S coating on RAW 264.7 macrophages. C2S and 45S5 coatings were characterized using scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive analysis (EDS) and X-ray diffraction (XRD). inductively coupled plasma optical emission spectroscopy (ICP-OES) was used to detect ionic concentrations after soaking coated discs in medium. The cytotoxicity of C2S and 45S5 coatings against RAW 264.7 macrophages was measured using the LDH Cytotoxicity Assay Kit, Cell Counting Kit-8 (CCK-8) assays and flow cytometry for apoptosis assays. The gene and protein expression of TNF-α, IL-6 and IL-1ß were detected using RT-q PCR and ELISA, respectively. The tested coating materials are not cytotoxic to macrophages. The C2S-coated surface stimulated macrophages to express pro-inflammatory mediators, such as TNF-α, IL-6 and IL-1ß, and C2S coating caused less IL-6 but greater IL-1ß production than the 45S5 coating. C2S coating have no cytotoxicity when directly cultured with macrophages. C2S and 45S5 coatings both have the potential to induce pro-inflammatory effects, and the biocompatibility of C2S is similar to that of 45S5.

Correlation analysis of computed tomography imaging score with the presence of acute kidney injury in severe acute pancreatitis.

OBJECTIVES: The aim of the study is to investigate the CT imaging findings of severe acute pancreatitis (SAP) complicated with acute kidney injury (AKI) and evaluate the correlation between the CT imaging score and the presence of AKI in SAP. MATERIALS AND METHODS: Contrast-enhanced CT scanning was performed for all 145 patients. Related CT indices such as Balthazar CT grading, CTSI and EPIC scores were calculated. Clinical data, including APACHE II, Ranson scores, serum creatinine levels, urine output, and mortality, were then collected and compared with CT indices. RESULTS: The EPIC score showed a larger area under the receiver operating characteristic curve than either of the CTSI or Balthazar score. However, the change of APACHE II score, but not EPIC score, was significantly associated with the prognosis of AKI and eventual clinical outcome. In addition, the CT manifestation of fluid encapsulation was a good predictor of recovery from AKI. CONCLUSIONS: Among the CT indices, the EPIC score, which possessed a good correlation with both APACHE II and Ranson scores, provided a better prediction of AKI in SAP patients than CTSI and Balthazar scores. Encapsulation of inflammatory exudates might be used in the future as imaging-based prognostic criteria of recovering from AKI in patients with SAP.

Assessment of intrarenal oxygenation in renal donor with blood oxygenation level-dependent magnetic resonance imaging.

OBJECTIVE: To examine change of the apparent relaxation rate R2* values in living kidney donors after uninephrectomy using blood oxygenation level-dependent magnetic resonance imaging. METHODS: Between July 2011 and January 2012, 45 kidney donors were enrolled into this study. Blood oxygenation level-dependent magnetic resonance imaging scanning was performed before surgery, 3 and 7 days postoperatively. Participants were followed up for 1 year. RESULTS: The R2* values in medulla (mR2*) were significantly greater than that of cortex (cR2*), both in resected kidney and remaining one. cR2* values of the remaining kidney was 17.52 ± 1.36 s(-1) and then decrease significantly by 8.97% to 15.95 ± 1.14 s(-1) at 3 days (P <.001) and by 7.82% to 16.15 ± of 1.05 s(-1) at 7 days. No significant modification occurred in mR2* after surgery. Multivariate regression analysis showed that the decrease in cR2* values of the remaining kidney was positively associated with sex (r = 0.418), body surface area (r = 0.307), and preoperative cR2* values (r = 0.659). Comparing with glomerular filtration rate at 7 days, a further increment in the glomerular filtration rate was noted at 1 year in patients with cR2* values decrease of ≥ 10% at 1 week (62.63 ± 11.69 vs 56.97 ± 7.51 mL/min/1.73 m(2), P = .02) but not in the other patients (66.43 ± 10.89 vs 62.78 ± 13.74, P = .064). CONCLUSION: Kidney donation will induce early, profound oxygenation modification within the renal cortex of the remaining kidney. Donors with cR2* value decrease of ≥ 10% at 1 week have a more favorable renal function compensation at 1 year.