Objective To explore the application value of deep learning image reconstruction(DLIR)with coronary computed tomography angiography(CCTA)using 100 kV.Methods Sixty patients who underwent CCTA were selected.The tube voltage of 100 kV,noise index of 24 were applied.The 60％adaptive statistical iterative reconstruction-Veo(ASIR-V)and DLIR-low(DLIR-L),DLIR-medium(DLIR-M)and DLIR-high(DL1R-H)were reconstructed.The CT values and standard deviation(SD)values of the aortic root,left main artery,left anterior descending artery,left circumflex artery,right coronary artery and pericardial fat of the four groups of images were measured,and the signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)were calculated.Two radiologists with five-year working experience subjectively evaluated the image quality using a five-point method double-blindly.Results The differences in noise(SD values),SNR values and CNR values among the four groups of images were statistically significant(P＜0.001).As the reconstruction gradually changed of 60％ASIR-V,DLIR-L,DLIR-M and DLIR-H,the coronary SD values gradually decreased,while the SNR values and CNR values gradually increased,among which the DLIR-H had the lowest SD values and the highest SNR values and CNR values.The subjective scores of the four groups of images by two radiologists showed good consistency(Kappa value=0.929,P＜0.001),and the subjective scores were all above 3 points which met the clinical diagnosis criteria.The subjective scores of DLIR-L,DLIR-M and DLIR-H were significantly higher than those of 60％ASIR-V(P＜0.001),with the DLIR-H achieving the highest subjective score.Conclusion DLIR can significantly reduce image SD value and improve image quality of CCTA with 100 kV,among which DLIR-H has the best effect on improving CCTA image quality.

Objective To develop the UHPLC-MS/MS method for the determination of amygdalin, paeoniflorin, ferulic acid, calycosin glucosidase, quercetin and formononetin in Buyang-Huanwu decoction. Methods Isocratic elution was carried out with mobile phase consisting of methanol- 2 mM ammonium formate. The separation was performed on Agilent ZORBAX SB-C18 maintained at 35 ℃. The flow rate was 200 μl/min, and the injection volume was 2 μl. The mass spectrometer was operated in the positive and negative ionization electrospray (ESI) mode using multiple monitoring (MRM) for analysis of six components. The mass spectrometric conditions were that ion source temperature 400 ℃, dry gas flow 500 L/h, atomization gas flow rate 75.8 Kpa, spray voltage 4000 V, dry gas temperature 400 ℃. Results The amygdalin, paeoniflorin, ferulic acid, calycosin glucosidase, quercetin and formononetin were all analyzed exactly, and the linear ranges were 0.5-32, 0.2-12.8, 0.1-6.4, 0.8-51.2, 0.4-25.6, 0.08-5.12 ng, respectively. The r were 0.9921, 0.9945, 0.9928, 0.9958, 0.9947, 0.9966, respectively. The recoveries of six analytes ranged from 99.21％ to 101.44％ and the relative standard deviations were all below 2.05％. Conclusions A sensitive, accuracy and suitable UHPLC-MS/MS method has been developed, and the method could be applied for the determination of amygdalin, paeoniflorin, ferulic acid, calycosin glucosidase, quercetin and formononetin in Buyang-Huanwu decoction.

Objective: A predictive model of WHO/ISUP grading of renal clear cell carcinoma was constructed based on CT radiomics. Methods: The clinical data of 104 patients with ccRCC confirmed by operation or biopsy from March 2014 to December 2018 in the Affiliated Hospital of Shaanxi University of Traditional Chinese Medicine were retrospectively analyzed. There were 70 males and 34 females, and the age was 61.2±11.7 years. The patients were randomly divided into development cohort (73 cases) and validation cohort (31 cases) by stratified sampling according to 7∶3 ratio. According to the WHO/ISUP pathological grading criteria of renal cancer in 2016, Ⅰ and Ⅱ were defined as low-grade group, Ⅲ and Ⅳ were defined as high-grade group. The radiomics features of ccRCC were calculated in cortical phase images of CT enhanced scanning. LASSO regression was used to reduce the radiomics feature dimensionality in the training group, and to establish radiomics risk scores. The binary logistic regression was used to build the prediction model, which was used in the validation group. Bootstrap method was used to validate the model of training and validation group. AUC, sensitivity and specificity were calculated respectively. Hosmer-Lemeshow goodness-of-fit test was used to evaluate model calibration degree. Results: After dimensionality reduction, the radiomics risk score of ccRCC was established. The low and high-level risk scores of the training group were -2.49±1.73 and 1.23±2.17, with significant difference (t=-7.785, P < 0.01). The binary logistic regression multivariate analysis showed that the radiomics risk score was an independent risk factor in identifying low or high-grade ccRCC with odds ratio of (OR=3.576, 95%CI 1.964~6.513). The predictive model was Y=1/[1+ exp(-Z)], Z=1.274×radiomics risk score+ 0.072. The AUC of radiomics risk score in training group was 0.940 (95%CI 0.883-0.998) with 95.5% sensitivity and 88.2% specificity after internal verification by Bootstrap method, and good Hosmer-Lemeshow goodness-of-fit test (χ²=4.463, P>0.05). The low and high-level risk scores of the Validation group were -2.27±2.02 and 0.82±2.08, with significant difference (t=-3.832, P<0.01). The AUC in validation group was 0.859(95%CI 0.723-0.995) with 77.8% sensitivity and 81.8% specificity, and with good Hosmer-Lemeshow goodness-of-fit test (χ²=14.554, P=0.068) as well. Conclusions The prediction model based on CT radiomics has high accuracy in predicting high or low grade of ccRCC.

Objective To demonstrate the feasibility of high-resolution computed tomography(HRCT)reconstructed with a model-based iterative reconstruction (MBIR)for evaluating early peripheral lung cancer (≤3 cm),by comparing image quality obtained from MBIR,filtered back proj ection reconstruction(FBP)and state of the art adaptive statistical iterative reconstruction(ASIR)algorithm respectively.Methods A total of 30 patients confirmed with lung cancer by postoperative pathology were enrolled in the study.A chest phantom was also used to evaluate image noise,spatial resolution and density resolution.Both patients and chest phantom were received HRCT,and the images were reconstructed using FBP,ASIR(40% ASIR and FBP mix)and MBIR.The objective CT value, standard deviation(SD)and signal noise ratio(SNR)were measured.Two radiologists used a semi-quantitative to rate subjective image quality of lung nodules.Results There was no significant difference in CT value between the three reconstruction algorithms (P>0.05).But significant improvements in objective image noise were observed in MBIR compared with FBP and ASIR (P<0.05):including the SD value in back muscle [(12.63±1.70)with MBIR vs (31.58±5.21)with FBP and (24.55±4.14)with ASIR],and in subcutaneous fat [(12.77±2.53)vs (24.39±5.08)and (19.20±4.11)].Subjective image noise of the three group were also significantly difference:FBP with lowest subjective noise score;and MBIR with highest subjective noise score.The sharpness of small vessels and bronchi and diagnostic acceptability with MBIR were significantly better than with FBP and ASIR (P< 0.05).Conclusion Lung HRCT reconstructed with MBIR provides diagnostically more acceptable images for the detailed analyses of peripheral lung cancer compared with FBP and ASIR.

Objective To compare the spatial resolution and density resolution balance algorithm(MBIRSTND)and spatial resolution preference algorithm (MBIRRP20)from new version of model-based iterative reconstruction(MBIRn),and adaptive statistical iterative reconstruction(ASIR) with lung kernel in routine dose about the performance of computer-aided detection (CAD)for quantitative analysis of airway.Methods 30 patients were involved who were scanned for pulmonary disease with spectrum CT.Data with a slice thinkness 0.625 mm were reconstructed with ASIR,MBIRSTNDand MBIRRP20.Airway dimensions from three reconstruction algorithm images were measured using an automated and quantitative software(Dexin-FACT)that was designed to segment and quantify the bronchial tree,and a skeletonization algorithm to extract the center-line of airway trees automatically.For each patient,reconstruction algorithm chose the right middle lobe bronchus,and the bronchial length of the matched airways was measured by this scheme.Two radiologists used a semiquantitative 5 scale (Score 0 stands for its image quality is similar to that with ASIR;Score±1 stand for a little better or a little worse;Score±2 stand for obviously better or obviously worse)to rate subjective image quality of airway trees about images reconstructed with MBIRSTNDand MBIRRP20.Paired t test and Wilcoxon signed-rank test were used.Results Algorithm impacts the measurement variability of bronchus length in chest CT.The bronchial length with MBIRRP20was longer than with MBIRSTND, while the length with ASIR were the shortest(P<0.05).In addition, the optimal reconstruction algorithm was found to affect the subjective noise,the continuity and completeness of bronchial wall,and the show of bronchial end.The subjective noise of MBIRSTNDwas better than that of MBIRRP20.The show of bronchial end of MBIRRP20was better than that of MBIRSTND(P<0.05).There was no significant difference in the continuity and completeness of bronchial wall compared with MBIRRP20and MBIRSTND(P>0.05),which was much better than with ASIR(P<0.05).Conclusion MBIRn can inmprove the analyzing ability of CAD airway.The MBIRSTNDcan significantly reduce the image noise,the MBIRRP20significantly improve the branching of the bronchial arteries,both of which can allow the desired airway quantification accuracy of CAD for chest CT of the bronchial wall.

Objective To explore the value of intravoxel incoherent motion DWI (IVIM-DWI) combined with single-voxel MRS in distinguishing osteoporotic fractures from metastatic vertebral compression fractures.Methods Totally 70 patients with vertebral compression fractures,who underwent CT scanner were enrolled.The patients were divided into osteoporotic group or metastatic group based on pathological results or clinical follow-up.All patients underwent conventional sagittal T1W,T2W,STIR,IVIM-DWI and single-voxel MRS scanning.Relative peak areas of the signal of water at 4.7 ppm and lipid at 1.3 ppm were determined.IVIM-DWI parameters (diffusion coefficient [D],pseudo diffusion [D*],perfusion fraction [f]) and MRS parameters (lipid water ratio [LWR],fat fraction [FF]) were also recorded.The diagnostic performance of MRS,IVIM-DWI,as well as MRS combined with IVIM-DWI in distinguishing osteoporotic fractures from metastatic vertebral compression fractures were evaluated by using ROC curve,and the area under curve (AUC) was calculated.Results The f,D and FF in metastatic group were significantly lower than those in osteoporotic group,while D* in metastatic group was significantly higher than that in osteoporotic group (all P＜0.05).The sensitivity,specificity and accuracy in differentiating osteoporotic fractures from metastatic vertebral compression fractures was 87.50％ (28/32),57.89 (22/38) and 71.43％ (50/70) of MRS,78.13％ (25/32),89.47％ (34/38) and 84.28％ (59/70) of IVIM-DWI,90.63％ (29/32),97.37％ (37/38) and 94.29％ (66/70) of MRS combining with IVIM-DWI,respectively.AUC of MRS,IVIM-DWI,as well as MRS combined with IVIM-DWI was 0.73,0.88 and 0.94 (all P ＜0.05),respectively.Conclusion Combination of IVIM-DWI and MRS can improve the diagnostic efficiency of differentiating osteoporotic fractures from metastatic vertebral compression fractures.

Objective To assess image quality of adaptive statistical iterative reconstruction (ASIR),conventional modelbased iterative reconstruction (MBIRc) and a new lung-specific setting (MBIRRP20 and MBIRNR40) from the new version of model-based iterative reconstruction (MBIRn) in submillisievert chest CT comparing with ASIR in standard-dose.Methods Two chest CT examinations were performed with standard-dose and low-dose in 30 patients.Low-dose CT images were reconstructed with ASIR,MBIRc and MBIRn,while standard-dose CT images were reconstructed with ASIR only.Objective image noise and SNR were measured on the same part from the back muscle and subcutaneous fat which located at the level of thoracic entry,trachea carina and hepatic portal.Image quality of lung,mediastinum and upper abdomen structures were evaluated on a 5-point scale.The results were compared with one-way ANOVA and Wilcoxon signed-rank tests.Results The effective dose equivalent for standard-dose CT was (3.01 ± 1.89) mSv,compared with (0.88 ± 0.83) mSv for low dose CT,which decreased by 70.76％.The mean image noise for low-dose MBIRNR40 was significantly lower than that of conventional-dose ASIR,low-dose ASIR and MBIRc (P＜0.05).The mean SNR for low-dose MRIRNR40 was significant ly higher than that of conventional dose ASIR,low-dose ASIR and MBIRc (P＜0.05).The subjective image noise score was significantly lower than that of ASIR and MBIRc,and the score of sharpness of details of the structures score for low dose MBIRn was significantly better than that of the ASIR and MBIRc (P＜0.05).Conclusion MBIRNR40 can significantly reduce image noise and improve SNR compared to ASIR and MBIRc in low-dose,even better than ASIR in standard dose,which reduce radiation dose by about 70％.In low-dose,MBIRPP20 can well display lung structures,and MBIRNR40 can display mediastinal and the upper abdominal structures.

Purpose To explore the value of spectral coronary CT angiography (CCTA) in reducing radiation dose and contrast dose using individualized optimal monochromatic imaging.Materials and Methods Sixty patients with suspected coronary disease were recruited in the study,who were randomly divided into two groups:group A (n=30) using conventional CT protocol with 350 mgI/ml contrast agent;group B (n=30) using low dose spectral CT imaging mode with 300 mgI/ml contrast agent.The images of group A were reconstructed with conventional process,and the images of group B were reconstructed with Optimal CNR to obtain the optimal monochromatic energy images.The images of both groups were transferred to an Advanced Workstation for analysis.Double-blinded method was carried out to qualify the images.CT values of coronary artery segments,as well as standard deviations (SD),the signal-to-noise ratio (SNR),contrast-to-noise ratio (CNR) of aortic sinus were measured.Radiation doses and iodine intake were compared between the two groups.The optimal keV distribution in group B was analyzed.Results There was no significant difference for the subjective scoring of image quality,CT value of each coronary artery segment,SD,SNR,and CNR values between the two groups (P＞0.05).The effective radiation dose and total iodine load in group B were less than that in group A (P＜0.05).The optimal energy distribution for group B was 60-75 keV,average at (66.50+3.91) keV.Conclusion Compared with the conventional CT protocol,spectral CT imaging at optimal energy levels combined with iterative reconstruction can effectively reduce the radiation dose and iodine load,and obtain better images than usual protocol.

Objective To compare the effect on image quality of low-dose upper abdominal CT reconstructed with the new version of model-based iterative reconstruction (MBIRn) focused on low-contrast resolution (MBIRNR40),conventional model-based iterative reconstruction (MBIRc),adaptive statistical iterative reconstruction (ASIR) and routine-dose CT reconstructed with filtered back projection (FBP).Methods Water plantom at rest was scanned with CT,and spatial resolution and density resolution were compared among FBP,ASIR,MBIRc,and MBIRNR40.Sixty patients with 2 times CT in the upper abdomen within a year were enrolled.The initial examination was acquired at a standard radiation dose (noise index [NI] of 10 HU) and reconstructed with the conventional FBP algorithm.The follow-up scan was acquired at a lowdose (NI=20 HU) and reconstructed with the standard ASIR,MBIRc and MBIRNR40.All images were obtained with 0.625 mm slice thickness.CT values and noise of fat,muscle as well as the liver and kidney parenchyma were measured and CNR of liver and kidney parenchyma using the fat SD as background image noise were calculated.Two radiologists independently graded images for noise,sharpness of details of structures and lesion.The quantitative image quality scores of different reconstructions were analyzed with one-way ANOVA using FBP reconstruction as reference of standard.The degree of interobserver consistency was evaluated using Kappa test.Results The phantom study revealed the highest spatial resolution with MBIRc and highest density resolution with MBIRNR40 among all reconstructions.The dose-length product and radiation dose for the first inspection was (93.18 ± 41.21) mGy · cm,(1.40 ± 0.62) mSv,respectively,and were (368.03 ± 146.25)mGy · cm,(5.52 ± 2.19)mSv for the second inspection,representing an approximate overall dose reduction of 74.68％ and 74.64％.The mean image noise of muscle and fat for MBIRNR40 was significantly lower than that of MBIR,ASIR and FBP(P＜0.05).The mean CNR values of liver and spleen for MBIRNR40 were significantly higher than that of ASIR,MBIRc and FBP (P＜0.05).Two radiologists had a good subjective score consistency.Low-dose MBIRNR40 subjective image noise was the lowest,showing the most detailed on the upper abdominal detail structure and lesion edge,better than MBIRc,MBIRc was superior to routine-dose FBP,low dose ASIR was worst,the difference was statistically significant (P＜0.05).Conclusion With 75％ dose reduction in upper abdominal CT,the MBIRNR40 can provide well objective and subjective image quality than MBIRc and ASIR40,and the routine-dose FBP.

[Abstraet] Purpose To explore the application of noise reduction settings among modelbased iterative reconstruction (MBIRn) on decreasing radiation dose in CTA through experimental study.Materials and Methods Spectral CT was used to scan vessel model which could accommodate 8 tubes under static condition under 120 kVp fixed tube voltage at 10 mA,50 mA,150 mA and 600 mA.The tubes were filled with purified water,1,2,5,10,20 and 30 mgI/ml solutions and 30 mgCa/ml solution.Algorithms of FBP (standard),ASIR40 (combined by 40％ ASIR and FBP),MBIRc and MBIRn with optimized spatial resolution setting as MBIRRP20,MBIRstnd (standard setting),and MBIRNR40 (noise reduction setting) were adopted for original scanning data to reconstruct images of 0.625 mm slice thickness for contrastive analysis.Three fixed layers were chosen and regions of interest were placed on central tube and surrounding ester matrix,and CT value and standard variation (SD) were measured to represent noise.Noise reduction setting MBIRNR40 and solution noise of other reconstruction algorithm images were calculated and compared and average value of contrast noise ratio (CNR) was compared.Results Compared to FBP under different tube currents,ASIR40,MBIRc,MBIRRP20,MBIRstnd and MBIRNR40 reduce noise and increase CNR at different levels.Average noise of MBIRNR40 was the lowest (reduced by 78.33％) and CNR the highest (increased by 241.74％),making it superior to other reconstruction algorithm images (P＜0.05).Meanwhile,the lower the radiation dose was,the more obvious its advantage was.Reconstruction image noise of MBIRNR40 at 10 mA was close to that of FBP and ASIR40 at 600 mA.CNR was obvious greater than that of FBP and ASIR40 at other tube voltage.Conclusion Reconstruction algorithms of MBIRc,MBIRn and ASIR can help enhance CTA image quality and reduce radiation dose.Noise reduction setting MBIRNR40 from MBIRn has the lowest noise and greatest CNR.The lower the radiation dose is,the more obvious its advantage is.