Objective To observe the correlations of chest CT quantitative parameters and one-year readmission in patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Methods Totally 225 AECOPD patients were included and divided into the readmission group(group A,n=61)and non-readmission group(group B,n=164)according to whether readmitted due to acute exacerbation within one year or not.Quantitative CT parameters,including the percentage of low attenuation area volume to total lung volume(LAA％)and intrapulmonary vascular volume(IPVV)of the whole lung,left/right lung and each lobe,as well as the bronchial lumen area(LA)and percentage of bronchial wall area(WA％)of grades 3-8 were compared between groups.Spearman correlations were used to analyze the correlations between quantitative CT parameters and one-year readmission.Results LAA％of the whole lung,right lung,upper lobe of both lungs,middle lobe of the right lung,and lower lobe of the right lung in group A were higher than that in group B(all P＜0.05),which were weakly positively correlated with readmissions within one year(r=0.142-0.187,all P＜0.05).Significant differences of the upper lobe of right lung LAgrade 6,lower lobe of left lung LAgrade 6,lower lobe of left lung LAgrade 8,upper lobe of right lung WA％grade 5,upper lobe of right lung WA％grade 8 and lower lobe of left lung WA％grade 8 were found between groups,which were all correlated with readmissions within one year except for the lower lobe of the left lung LAgrade 6(all P＜0.05).Conclusion One-year readmission in AECOPD patients might be associated with severe airway remodeling and emphysema.

Objective To evaluate the application value of the MR three-dimensional double inversion recovery(3D DIR)sequence in the diagnosis of optic neuritis(ON).Methods A retrospective analysis was conducted on MRI images from 40 patients with sus-pected ON.All patients underwent conventional T2 WI fat suppression(FS)and 3D DIR sequences.The lesion detection rate and diag-nostic accuracy of the intraorbital,intracanalicular,and intracranial segments of the optic nerve were compared between the two sequences,respectively.The receiver operating characteristic(ROC)curves were used to assess the diagnostic performance,and the intraclass correlation coefficient(ICC)were used to analyze interobserver consistency.Imaging assessments were independently performed by two senior and two junior radiologists.Results The sensitivity(SEN),specificity(SPE),and accuracy(ACC)in lesion detection of 3D DIR sequence were significantly better than those of conventional T2 WI FS sequence[odds ratio(OR)221 vs 104,P＜0.001].Notably,3D DIR sequence exhibited superior performance in detecting lesions in the intraorbital segment[area under the curve(AUC)0.915,OR=102]and intracanalicular segment(AUC 0.858,OR=51)compared with conventional T2WI FS sequence.Additionally,3D DIR sequence significantly improved diagnostic consistency among junior radiologists(ICC value increased from 0.469 to 0.655),bring-ing their diagnostic performance closer to that of senior radiologists(AUC improved to 0.883,ACC reached 90.1％).Conclusion The 3D DIR sequence has outstanding diagnostic efficacy in detecting ON lesions,significantly improving ACC and interobserver consistency,thereby offering strong support for the precise diagnosis of ON.

Objective To evaluate the application value of the MR three-dimensional double inversion recovery(3D DIR)sequence in the diagnosis of optic neuritis(ON).Methods A retrospective analysis was conducted on MRI images from 40 patients with sus-pected ON.All patients underwent conventional T2 WI fat suppression(FS)and 3D DIR sequences.The lesion detection rate and diag-nostic accuracy of the intraorbital,intracanalicular,and intracranial segments of the optic nerve were compared between the two sequences,respectively.The receiver operating characteristic(ROC)curves were used to assess the diagnostic performance,and the intraclass correlation coefficient(ICC)were used to analyze interobserver consistency.Imaging assessments were independently performed by two senior and two junior radiologists.Results The sensitivity(SEN),specificity(SPE),and accuracy(ACC)in lesion detection of 3D DIR sequence were significantly better than those of conventional T2 WI FS sequence[odds ratio(OR)221 vs 104,P＜0.001].Notably,3D DIR sequence exhibited superior performance in detecting lesions in the intraorbital segment[area under the curve(AUC)0.915,OR=102]and intracanalicular segment(AUC 0.858,OR=51)compared with conventional T2WI FS sequence.Additionally,3D DIR sequence significantly improved diagnostic consistency among junior radiologists(ICC value increased from 0.469 to 0.655),bring-ing their diagnostic performance closer to that of senior radiologists(AUC improved to 0.883,ACC reached 90.1％).Conclusion The 3D DIR sequence has outstanding diagnostic efficacy in detecting ON lesions,significantly improving ACC and interobserver consistency,thereby offering strong support for the precise diagnosis of ON.

Objective To observe the correlations of chest CT quantitative parameters and one-year readmission in patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Methods Totally 225 AECOPD patients were included and divided into the readmission group(group A,n=61)and non-readmission group(group B,n=164)according to whether readmitted due to acute exacerbation within one year or not.Quantitative CT parameters,including the percentage of low attenuation area volume to total lung volume(LAA％)and intrapulmonary vascular volume(IPVV)of the whole lung,left/right lung and each lobe,as well as the bronchial lumen area(LA)and percentage of bronchial wall area(WA％)of grades 3-8 were compared between groups.Spearman correlations were used to analyze the correlations between quantitative CT parameters and one-year readmission.Results LAA％of the whole lung,right lung,upper lobe of both lungs,middle lobe of the right lung,and lower lobe of the right lung in group A were higher than that in group B(all P＜0.05),which were weakly positively correlated with readmissions within one year(r=0.142-0.187,all P＜0.05).Significant differences of the upper lobe of right lung LAgrade 6,lower lobe of left lung LAgrade 6,lower lobe of left lung LAgrade 8,upper lobe of right lung WA％grade 5,upper lobe of right lung WA％grade 8 and lower lobe of left lung WA％grade 8 were found between groups,which were all correlated with readmissions within one year except for the lower lobe of the left lung LAgrade 6(all P＜0.05).Conclusion One-year readmission in AECOPD patients might be associated with severe airway remodeling and emphysema.

Objective To observe the correlations of chest CT quantitative parameters in patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD)with blood eosinophil(EOS)level.Methods Chest CT data of 162 AECOPD patients with elevated eosinophils were retrospectively analyzed.The patients were divided into low EOS group(n=105)and high EOS group(n=57)according to the absolute counting of blood EOS.The quantitative CT parameters,including the number of whole lung bronchi and the volume of blood vessels,low-attenuation area percentage(LAA％)of whole lung,of left/right lung and each lobe of lung,as well as the luminal diameter(LD),wall thickness(WT),wall area(WA)and WA percentage of total bronchial cross-section(WA％)of grade 3 to 8 bronchi were compared between groups.Spearman correlations were performed to analyze the correlations of quantitative CT parameters with blood EOS level.Results LAA％of the whole lung,of the left/right lung and each lobe of lung,as well as of the upper lobe of right lung LDgrade4,middle lobe of right lung WTgrade5,upper lobe of right lung WAgrade4,middle lobe of right lung WAgrade5 and lower lobe of left lung WAgrade3 in low EOS group were all higher than those in high EOS group(all P＜0.05).Except for the upper lobe of right lung LDgrade4,the above quantitative CT indexes being significant different between groups were all weakly and negatively correlated with blood EOS level(r=-0.335 to-0.164,all P＜0.05).Conclusion Chest CT quantitative parameters of AECOPD patients were correlated with blood EOS level,among which LAA％,a part of WT and WA were all weakly negatively correlated with blood EOS level.

Objective:To investigate the feasibility of classifying imaging patterns of dermatomyositis/polymyositis-related interstitial lung disease (DM/PM-ILD) into subtypes based on chest CT radiomics features and a model was constructed by machine learning algorithms.Methods:From November 2011 to November 2020, 107 patients diagnosed with PM/DM-ILD at the First Affiliated Hospital of Xi′an Jiaotong University were retrospectively analyzed. A total of 315 cases with chest CT were collected. Doctors pre-classified image patterns, including 105 cases with non-specific interstitial pneumonia (NSIP), 90 cases with organizing pneumonia (OP), and 66 cases with non-specific interstitial pneumonia combined with organizing pneumonia (NSIP+OP), 35 cases with common interstitial pneumonia (UIP), and 19 cases with diffuse alveolar damage (DAD), ANOVA was used to test the difference of baseline clinical information among the imaging classification groups. All images were divided into the training set and the est set by stratified random sampling at a ratio of 4∶1. In each CT scan, 3D slicer was used to segment each lung lobe, and then reconstructed into 3 mm 3 of voxels, and Pyradiomics library was used to extract the radiomic features of the whole lung and each lobe. The multi-classification goal was achieved by constructing random forest base classifiers for each of the five groups and then voting as the final model. In the process of constructing the base classifier, firstly, the balance between sample groups was achieved by SMOTETomek comprehensive sampling, and the optimal feature set was selected by independent sample t test and L1 regularized least absolute shrinkage and selection operator (LASSO) regression. In this study, the Radiomics model was constructed based on chest CT radiomics features, and the Radiomics + model was constructed by introducing gender and age information. The base classifier and the integration model use the mean accuracy and the area under the receiver operator characteristics analysis curve (AUC) to evaluate the performance, respectively. Results:There was a statistically significant difference ( P<0.05) between the ages of the NSIP, OP, NSIP+OP, UIP, and DAD groups [(57±13),(53±8),(54±10),(44±11), and (46±8)years old, respectively], F=11.82, P<0.001. In the Radiomics model, for each group of NSIP, OP, NSIP+OP, UIP, and DAD, the AUCs of the training set were 0.87, 0.91, 0.91, 0.96, and 0.99, respectively, and the AUC of the test set were 0.81, 0.82, 0.79, 0.93, 0.89. In the final Radiomics + model, for each group of NSIP, OP, NSIP+OP, UIP, and DAD, the AUCs of the training set were 0.89, 0.91, 0.92, 0.97, and 0.99, respectively, and the AUCs of the test set were 0.84, 0.82, 0.78, 0.94, 0.90. Conclusion:Based on chest CT radiomics features and key clinical features (sex, age), the Radiomics + model constructed by machine learning has good classification performance for the imaging patterns of PM/DM-LD.

【Objective】 To investigate the airway parameters of adult-onset eosinophilic asthma （EA） and analyze the correlation between airway remodeling and lung function by quantitative CT. 【Methods】 From March 2015 to November 2016， totally 94 subjects from the “FACT-Digital Lung” Multi-research Center were divided into three groups： 30 normal subjects， 33 EA patients and 31 non-eosinophilic asthma （NEA） patients. We measured and recorded the bronchial parameters of RB1， LB1+2， RB10， and LB10， and small airway disease parameters. The indicators for quantitative evaluation of bronchial parameters include lumen area （LA）， wall thickness （WT）， wall area （WA）， and wall area percentage （WA%）. The parameters for the quantitative assessment of small airway disease included the percentage of inspiratory voxels below -950HU （IN-950）， the mean lung density （MLDin）， and the whole volume of the lung in inspiration （Vin）. Pearson or Spearman rank correlation analysis was used to evaluate the correlation between these parameters and lung function. 【Results】 The differences in LA/BSA， WT/√BSA， and WA/BSA between the three groups were statistically significant （P<0.05）. FEV1% had a significant correlation with IN-950 and MLDin （P<0.01）. FEV1/FVC had a significant correlation with Vin， IN-950， and MLDin （P<0.01）. EOS counts were positively related to IN-950 （r=0.343， P=0.011）， while EOS had a negative correlation with FEV1% （r=－0.343， P=0.015）. 【Conclusion】 With the increase of eosinophils counts in peripheral blood， the airway's stenosis in asthma patients gradually increased， and the extent of airflow limitation steadily increased. The IN-950 may be a sensitive imaging biomarker for evaluating the small airway disease in adult-onset eosinophilic asthma patients.

Objective To establish and validate a voxel-based method for the quantitative detection of air trapping (AT),and to explore its diagnostic value by preliminarily apply this method in chronic obstructive pulmonary disease (COPD) patients.Methods From March 2015 to February 2016,fifty healthy young volunteers and eighteen COPD patients who underwent both end-inspiratory and end-expiratory CT were included from the Digital Lung Multi-center Study.The quantitative parameters of AT and emphysema were measured by both the voxel-based quantitative method and the conventional threshold method,respectively.All subjects underwent pulmonary function examination within 3 days after CT examination.For healthy volunteers,paired sample rank-sum test was used to compare the difference of quantitative parameters between voxel-based method and threshold method,Spearman rank correlation analysis was used to investigate the correlation between quantitative parameters of the two methods and pulmonary function.For COPD patients,the distribution and extent of AT and emphysema in patients with similar degree of pulmonary function (PFT) injury were observed.Results There were varying degrees of AT in the asymptomatic youth,with a median value of 5.70％ for the voxel-based method and with a median value of 7.96％ for the conventional threshold method,there was significant difference(Z=-4.015,P＜0.001).The correlation between AT and emphysema parameters of the voxel-based method and PFT parameters (r=-0.399 and-0.494,-0.335 and-0.439 separately,P＜0.05) were higher than that of the conventional threshold method,respectively (r=-0.357 and-0.453,-0.284 and-0.391,respectively;all P＜0.05).Furthermore,the voxel-based method can classify COPD patients with similar degree of pulmonary function injury into three subtypes:AT-dominant,emphysema-dominant,and mixed.Conclusions The voxel-based AT quantitative measurement method not only has high sensitivity and accuracy,but also provides imaging phenotype for the diagnosis of COPD and provides assistant decision-making for clinical management.

Objective To evaluate the extent and anatomic distribution of air trapping in lung in young asymptomatic female subjects to achieve early diagnosis of small airway diseases.Methods Fifty young females with normal pulmonary function were included retrospectively in this study.All subjects underwent both inspiratory and expiratory CT scans,the percentage of the area of air trapping(AT)and the percentage of the area of emphysema(Emph)were quantitatively analyzed.Comparison between bilateral lungs was analyzed using independent-samples t test;Comparisons among lobes were done using one-way ANOVA or Kruskal-Wallis rank sum test;Pairwise comparisons between lobes were conducted using LSD test or paired comparison;The effects of each lobe on AT were analyzed using Spearman's rank correlation coefficient,simple linear regression and multiple stepwise regression.Results There was a certain degree of air trapping in lung and a small amount of emphysema in young asymptomatic females.Air trapping was mainly located in the right middle lobe (RML)and bilateral upper lobes.The ratio of air trapping to volume was the highest in RML and the change of air trapping in the bilateral upper lobes had the greatest influence on the air trapping degree of the whole lung.Conclusion There is a certain degree of air trapping in lung in young asymptomatic females.The occurrence and development of air trapping in RML may be a sensitive biomarker for the early detection of pathophysiological changes in small airway diseases using imaging procedures.

Objective To study feasibility of differentiation of benign and malignant by using eccentric rate of calcification in pulmonary spherical lesions.Methods Two hundred and forty cases with pulmonary spherical lesions(malignant in 170 and benign in 70) confirmed by pathology or clinical follow-up were collected in this study.All cases were underwent chest CT examinations.Nodule CAD software was used to demarcation of pulmonary spherical lesions and internal calcification.Calcification was defined as an area more than 3 pixel with calcification density(CT value＞120 HU).Furthermore,the ratio of calcification center distanceand calcification edge distance was calculated as Ecc.Mann-Whitney U test was used to compare the eccentric calcification rates between the malignant and the benign pulmonary spherical lesions.Taking pathological results as golden standard,the diagnostic efficacy of Ecc was analyzed using ROC curves.Results In 240 lesions,65 calcifications were detected,of which 18 were malignant calcification distributed in 10 lesions,and 47 were benign calcifications distributed in 16 lesions.The median of Ecc in benign and in malignant lesions were 0.80(0.28-1.29) and 3.01(1.52-4.47).The Ecc of calcification in benign lesions were lower than those in malignant lesions (U=183.000,P＜0.01).Under the cut-off value of 1.00,benign calcifications were more likely to lie inner 1/2 part of lesion [61.70％(29/47)],while malignant calcifications were more likely to lie outer 1/2 part of lesion [77.78％(14/18)].The difference was statistically significant(x2=8.117,P＜0.01).Under the cut-off value of 1.72,the resultant sensitivity,specificity,accurate rate were 83.1％,77.8％,81.5％ respectively.The area under the ROC was 0.804.Conclusions Ecc exhibits the location characteristics of calcification and may be an ideal parameter in quantitative diagnostic modeling for providing evidence of quantitative diagnosis.