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Objective:To evaluate the reliability of cardiac late iodine enhancement dual-energy CT (LIE-DECT) multiparameter post-processing technique for evaluating the presence, location, and extent of cardiac scars in patients with heart failure (HF), using cardiac MR (CMR) late gadolinium enhancement (LGE) as a reference standard.Methods:Thirty-nine HF patients who underwent cardiac LIE-DECT and LGE-CMR examinations in the Second Affiliated Hospital of Nantong University from November 2019 to November 2021 were prospectively collected, all enrolled HF patients underwent LIE-DECT post-processing to reconstruct monoenergetic plus (Mono+) map (40 keV), iodine map and Rho/Z map, to evaluate the enhancement degree, location and extent of left ventricular myocardial LIE on the left ventricular short-axis map, respectively, and compared with LGE-CMR. Cohen′s Kappa test was used to assess the intra-and inter-observer consistency of LIE by DECT multiparameter technique and the consistency of LIE presence and location by DECT multiparameter technique and by CMR. The diagnostic efficacy of DECT multiparameter technique in diagnosing myocardial scar was calculated.Results:Of the 39 patients included, 32 patients were detected by CMR with LGE in 147 segments, including 37 subendocardial patterns, 19 transmural patterns, 74 mid-wall patterns, and 17 epicardial patterns. The intra-observer consistency Kappa values of 40 keV Mono+map, iodine map and Rho/Z map were 0.878, 0.930 and 0.835 ( P all<0.001), respectively. The inter-observer consistency Kappa values were 0.838, 0.892 and 0.808 ( P all<0.001), respectively. The LIE of 40 keV Mono+map, iodine map and Rho/Z map were in good agreement with CMR, Kappa values were 0.903, 0.883 and 0.810 ( P all<0.001), respectively. For the per-patient analysis, the accuracies of 40 keV Mono+map, iodine map and Rho/Z map were 92.3% (36/39), 92.3% (36/39) and 82.1% (32/39), respectively. For the segment-based analysis, the accuracies of 40 keV Mono+map, iodine map and Rho/Z map accuracy were 96.1% (492/512), 95.3% (488/512) and 92.6% (474/512), respectively. In Bland-Altman analysis, the consistency bias between scar extent measured by 40 keV Mono+map, iodine map, Rho/Z map and that measured by LGE-CMR were -2.03%, -2.21%, -2.65%, and the 95% limit of agreement were -12.20%-8.14%, -12.69%-8.28% and -14.85%-9.58%, respectively. Conclusion:LIE-DECT multiparameter technique can detect myocardial scar in HF patients well, which is consistent with LGE-CMR.
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Objective:To investigate the value of ADC map-based radiomics model for identifying the ischemic penumbra (IP) in acute ischemic stroke (AIS).Methods:From January 2014 to October 2019, data of 241 patients with AIS involving the anterior cerebral circulation within 24 h after stroke onset in the First People′s Hospital of Nantong City was analyzed retrospectively. All patients received routine T 1WI, T 2WI, DWI and dynamic susceptibility contrast-perfusion weighted imaging (DSC-PWI). Considering the PWI-DWI mismatch model as the gold standard for determining IP, patients were divided into the PWI-DWI mismatch (84 cases) and PWI-DWI non-mismatch (157 cases) groups. The ROI of the low signal area and the surrounding area was drawn by two doctors at the maximum level of the lesions on the ADC maps. Then the images were imported into AK analysis software to extract the features. Firstly, the inter-class correlation coefficient was used to screen out the features with high consistency, then the maximum relevance and minimum redundancy (mRMR) and least absolute shrinkage and selection operator (Lasso) regression analysis were used to screen the features. The selected features were used to construct their own radiomics model. ROC curve was used to evaluate the performance of the models, and Delong test was used to compare the area under the curve (AUC) of the two models. Results:After screening, 12 features (LongRunLowGreyLevelEmphasis_angle135_offset7, LongRunLowGreyLevelEmphasis_AllDirection_offset7, GLCMEntropy_AllDirection_offset4_SD, GLCMEnergy_angle45_offset1, ColGE_W11B25_16, ColGE_W11B25_24, HaraEntropy, SurfaceVolumeRatio, Sphericity, Quantile0.025, uniformity and Percentile75) were used to construct the radiomics model based on the low signal area of the ADC map. The area under the ROC curve in the training set was 0.900, and the sensitivity, specificity and accuracy were 84.5%, 81.4% and 83.4%, respectively. The area under the ROC curve in the validation set was 0.870, and the sensitivity, specificity and accuracy were 80.9%, 84.0% and 81.9%, respectively. Eleven features(RunLengthNonuniformity_AllDirection_offset1_SD, ShortRunLowGreyLevelEmphasis_angle45_offset1, HighGreyLevelRunEmphasis_AllDirection_offset1_SD, ShortRunLowGreyLevelEmphasis_AllDirection_offset7, HaralickCorrelation_AllDirection_offset4_SD, ClusterShade_angle45_offset7, InverseDifferenceMoment_AllDirection_offset7_SD, ColGE_W3B20_0, sumAverage, SurfaceVolumeRatio and VolumeMM) were used to construct the radiomics model based on the surrounding area of ADC map. The area under ROC curve in training set was 0.820, the sensitivity, specificity and accuracy were 80.5%, 80.2% and 80.4%, respectively; the area under ROC curve in validation set was 0.800, the sensitivity, specificity and accuracy were 78.7%, 80.0% and 79.2%, respectively. The AUC of the radiomics model based on the low signal area of the ADC map was larger than that based on the surrounding area of the ADC map (training set: Z=3.017, P=0.003; validation set: Z=0.604, P=0.002). Conclusion:The radiomics model based on ADC map has a good diagnostic efficacyin identifying the IP.
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Objective To investigate the effects of human urinary kallidinogenase (HUK) on cerebral perfusion,inflammatory marker level,neurological deficits,and short-term clinical outcomes in patients with acute ischemic stroke who exceeded the time window of thrombolytic therapy.Methods Patients with acute ischemic stroke exceeded the time window of thrombolytic therapy and treated in the Department of Neurology,the Second Affiliated Hospital of Nantong University from June 2016 to March 2018,and performed magnetic resonance perfusion imaging on the 1st and 14th d after admission were enrolled retrospectively.Patients were divided into HUK and control groups according to whether they received HUK treatment or not.All patients underwent magnetic resonance perfusion imaging and serum inflammatory markers measurement on the 1st and 14th d after admission.The National Institute of Health Stroke Scale (NIHSS) scores,cerebral perfusion levels,and serum inflammatory marker levels were compared between the 2 groups.On the 14thd after admission,the outcome was determined according to the modifiel Rankin Scale (mRS) scores.0-2 was defined as good outcome and ＞2 was defined as poor outcome.Multivariate logistic regression analysis was used to determine the independent influencing factors of outcome.Results A total of 62 patients with acute ischemic stroke exceeded the time window of thrombolytic therapy were enrolled,including 37 patients in the HUK group and 25 in the control group.There were no significant differences in the demographic and other baseline data between the HUK group and the control group,except for baseline NIHSS score (P =0.049).The reduction of NIHSS score after treatment in the HUK group was more significant than that in the control group (P ＜0.01).Serum high-sensitivity C-reactive protein level in the HUK group decreased significantly after treatment (P ＜ 0.01),and plasma lipoprotein-associated phospholipase A2 also showed a downward trend.In terms of perfusion imaging parameters,the relative cerebral blood flow was significantly increased after treatment in the HUK group,and the relative mean transit time and relative peak time were significantly decreased.The above increase and decrease were statistically significant compared with the control group (all P＜0.05).On the 14th d after admission,the mRS score showed that 51 patients had a good outcome and 11 had a poor outcome.Multivariate logistic regression analysis showed baseline NIHSS scores (odd ratio [OR] 2.545,95％ confilence interval [CI]1.124-5.541;P=0.024),atrial fibrillation (OR 5.712,95％ CI 1.737-24.685;P=0.039),and cardiogenic embolism (OR 4.485,95％ CI 1.148-18.262;P =0.040) were the independent risk factors for poor outcomes,and whether using HUK was not significantly associated with the outcomes.Conclusion For patients with acute ischemic stroke that exceeds the time window for thrombolysis,HUK improves cerebral perfusion,reduces inflammation,and improves neurological deficits in patients,but does not improve short-term neurological outcomes.
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Objective@#To assess the collateral grade based on 4-dimensional magnetic resonance angiography (4D-MRA) in predicting short-term outcome in patients with acute ischemic stroke (AIS) .@*Methods@#Forty-seven patients with unilateral MCA stroke were enrolled in this study. All patients underwent multi-modality MRI within 4.5 to 24.0 hours onset of stroke. The collateral grade was assessed through the dynamic MRI angiograms derived from perfusion raw data. The AIS patients were divided into favorable and unfavorable outcome group according to the improvement of national institutes of health stroke scale (NIHSS) score. The differences in baseline data, infarct volume, the ratio of volume of ischemic tissue on perfusion to infarct core on diffusion (rVPD) and collateral grade between the two groups were analyzed. Logistic regression analysis was used to identify variable influencing the short-term clinical outcomes. The Kappa coefficient was used to analyze the consistency of the collateral grade assessed between the two observers. Spearman rank-order correlation test was used to analyze the relationship between the collateral grade, infarct volume, hypoperfusion volume and rVPD.@*Results@#The collateral grade used ASITN/SIR based on 4D-MRA was performed in 47 patients. Grade 1 in 4 patients, grade 2 in 21paitients, grade 3 in 16 patients and grade 4 in 6 patients, respectively. The collateral grade had a high consistency among the observers (Kappa=0.806, P<0.01). Of the patients who enrolled the study, the median of infarct volume was 29.63 (4.92, 69.17) ml, the hypoperfusion volume was 73.76 (29.75, 178.42) ml, and the rVPD was 3.1 (1.5, 5.8). It was negatively correlated with initial infarct volume (r=-0.627, P<0.01) and hypoperfusion volume (r=-0.354, P<0.01) . There was a significant positive correlation between the collateral grade and rVPD (r=0.575, P<0.001). There was also significant differences in infarct volume, rVPD, and collateral grade between favorable and unfavorable outcome group (P<0.05). The collateral grade based on 4D-MRA was an independent predictor of favorable clinical outcome (OR=4.419, P<0.05) .@*Conclusions@#The collateral circulation classification based on 4D-MRA proved to be a significant predictor of clinical outcome, it can be considered as a reliable method for analyzing the cerebral hemodynamic changes and collateral grade in AIS patients.
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Objective To compare the effect of fluoroscopic triggering method and empirical delay method on image quality in the liver Gd-EOB-DTPA dynamic enhanced MRI,and to investigate the value of fluoroscopic triggering method in Gd-EOB-DTPA dynamic enhanced MRI.Methods The patients underwent Gd-EOB-DTPA dynamic enhanced MRI were randomly divided into two groups according to the starting modes in the artery phase.Group A used fluoroscopic triggering method and group B used empirical delay method.Eliminating the images with severe respiratory motion artifacts,the quality of the remaining images in 78 cases of group A and 85 cases of group B were assessed in scores (excellent=5 scores;good=4 scores).Data was statistically analyzed with Mann-whitney tests,and P<0.05 was considered statistically significant.Results The excellent rate of the images in group A was 96.15% (75/78).The excellent rate of the images in group B was 67.06% (57/85).There were significant differences between the two groups in the excellent rate (χ2=27.889, P<0.001)and the image quality scores (Z=-4.747,P<0.001).Conclusion For the liver Gd-EOB-DTPA dynamic enhanced MRI, fluoroscopic triggering method is more likely to get better image quality and higher success rate in artery phase than empirical delay method,which indicates that fluoroscopic triggering method have obviously advantages in clinical applications.
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Objective To evaluate the relationship between myocardial perfusion imaging quality and reconstruction time of dual-souce CT (DSCT).Methods Myocardial perfusion imaging was performed in 28 subjects using second-generation DSCT.The coronary arteries of all selected subjects were normal.280 ms temporal resolution was used,and the image of 30 ％-80 ％ R-R phase was reconstructed by retrospective ECG gating interval 5 ％.The artifact area of myocardial perfusion iodine map image of each R-R interval were obtained.Average segment artifacts of the heart bottom,central,apical,apical level of heart level were calculated and statistical analyzed.Results The artifact area of myocardial perfusion iodine map of the heart bottom,central,apical,and the whole heart had statistically significant differences (all P＜0.01),and the minimum artifact area was in60％ R-R phase ([0.31±±0.28]cm2,[0.18±0.23]cm2,[0.13±0.13]cm2,[0.22± 0.18]cm2).There was no difference between different phases of the heart apical level (P=0.634).The minimum artifact area of myocardial perfusion iodine map of the heart bottom,central,apical,apical level in 60％ R-R phase at the heart apical,the difference had statistically significant (F 3.701,P=0.014),there was no difference between the heart apical and central (P＞0.05),but the difference between the heart apical and other parts had statistically significant (P＜0.05).Conclusion Using 280 ms temporal resolution,second-generation DSCT can achieve the optimal myocardial perfusion imaging quality using 60％ R-R phase reconstruction.
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Objective To evaluate the diagnostic ability of fusion images of SWI and DWI in ischemic penumbra(IP)of patients with acute ischemic stroke(AIS).Methods 47 AIS patients were retrospective analyzed.Two neuroradiologists analyzed the fusion images of SWI and DWI respectively.SDM was defined as that the hypo-intensity signals of intramedullary or sulcal veins were dilated or increased on fusion images compared with contralateral areas.The results compared with the PDM,which was considered as the“gold standard”.Areas under the receiver operating characteristic curve(AUC)were used to assess the efficacy of SDM which determined by fusion images and compared to PDM.Chi-square test was used to analyze the consistency between the two neuroradiologists and also the consistency between SDM and PDM in IP assessment Results The fusion images of SWI and DWI had a high diagnostic efficacy compared to PDM, AUC of the two radiologists were 0.885,0.877,the diagnostic sensitivity were 84.2%,78.9% and specificity were 92.9%,96.4%respectively.There was also a high consistency in SDM assessment through fusion images between the two neuroradiologists (Kappa=0.908,P >0.05). Conclusion Fusion images of SWI and DWI have a high diagnostic efficacy in IP assessment,which may be considered as a simple approach for IP assessment in patients with AIS.
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Objective To evaluate the diagnostic value of intra-arterial thrombi under went susceptibility weighted imaging(SWI) in patients with acute ischemic stroke(AIS).Methods The MRI images of 133 patients with AIS was analyzed,included time of flight MR angiography(TOF-MRA )and SWI.The patients were divided into two groups according to the time between onset of symptoms and MR imaging (group A,interval time<24 h;group B,interval time 24-72 h).Two neuroradiologists who were blin-ded to the patients clinical information,documented the number and location of susceptibility vessel sign (SVS)in SWI and embolic occlusion or stenosis on TOF-MRA in AIS patients.Results The thrombus detection rate in group A was higher than that in group B.There was no significant difference in the overall detection rate of thrombi between SWI and TOF-MRA in all AIS patients,but the thrombi detection rate in M3 segement of middle cerebral artery(MCA)with SWI was higher than that with TOF-MRA in group A(P <0.05).Conclusion SWI performs a high diagnostic value for thrombus detection in AIS patients,especially for the thrombus detection of M3 segement in early period of AIS.
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Objective To evaluate the value of low-dose computed tomographic colonography (CTC) performed with 64-slice CT in the diagnosis of incidental extracolonic lesions and its clinical significance .Methods The image data in 158 CTC examinations with two positions were retrospectively analyzed .All abdominal extracolonic lesions were recorded .According to the age ,the pa-tients were divided into two groups :elderly and non-elderly groups .The extracolonic lesions were divided into 4 groups(E1- E4) according to the clinical importance .The incidence rates in two groups were calculated respectively .Results The incidence rate of the E2-E4 level extracolonic lesions in the elderly group was higher than that in the non -elderly group ,the difference between them had statistical signficance (P< 0 .05) .Conclusion Low-dose CTC has the high diagnostic value in finding extracolonic le-sions ,and the incidence rate of extracolonic lesions with important clinical significance is increased with the age increase ,especially for the elder patients over the age of 60 years .