Objective:To explore the clinical application value of MRI ultra-short echo time sequence (MRI-UTE) in the diagnosis of pulmonary nodules.Methods:This study was a cross-sectional study. A total of 101 consecutive patients were recruited prospectively from January to August 2024 at Huazhong Fuwai Hospital of Zhengzhou University. All of the included patients were diagnosed with pulmonary nodules by chest CT examination and intended for treatment. All patients underwent low-dose CT examination and MRI-UTE examination. The number, classification, and lung imaging reporting and data system (lung-RADS) grading of the pulmonary nodules were analyzed. Nodules classification was determined as solid nodules or sub-solid nodules, and sub-solid nodules included part-solid nodules and pure ground-glass nodules. Taking the evaluation results of radiologists with 10 and 12 years of experience in chest imaging diagnosis as the reference standard, the Kappa test was used to analyze the agreement of CT and MRI-UTE in terms of the accurate diagnosis, classification, and lung-RADS grading of pulmonary nodules. Results:Among the 101 patients, a total of 216 pulmonary nodules were identified. MRI-UTE accurately diagnosed 180 pulmonary nodules, while 203 pulmonary nodules were detected by CT. The concordance was moderate ( Kappa=0.48, P<0.001). In terms of nodule classification, CT correctly classified 167 nodules as solid and 36 as sub-solid, whereas MRI-UTE correctly classified 153 as solid and 23 as sub-solid, with good agreement (weighted Kappa=0.73, P<0.001). For lung-RADS grading, CT correctly graded 186 nodules, with 85 graded as category 2, 46 as category 3, 33 as category 4A, 12 as category 4B, and 10 as category 4X; MRI-UTE correctly graded 155 nodules, with 74 graded as category 2, 30 as category 3, 30 as category 4A, 12 as category 4B, and 9 as category 4X. The agreement between the two modalities in determining lung-RADS grade was also good (weighted Kappa=0.74, P<0.001). Conclusion:MRI-UTE demonstrates good agreement with CT in the accurate diagnosis, classification, and lung-RADS grading of pulmonary nodules, indicating certain clinical application value.

Objective:To assess the prognostic impact of the thoracic aorta and aortic valve calcification volume (TAC, AVC) score based on CT measurementsin patients undergoing transcatheter aortic valve implantation (TAVI).Methods:We retrospectively analyzed 102 patients who underwent TAVI for severe aortic stenosis from March 2018 to April 2022 at Fuwai Central China Cardiovascular Hospital. The patients were stratified into low TAC and AVC group (TAC low, AVC low) and high TAC and AVC group (TAC high, AVC high) based on median TAC and AVC. The independent risk factors affecting the prognosis of TAVI patients were analyzed using univariate and multivariate Cox proportional risk regression, and the independent risk factors affecting the prognosis of TAVI were analyzed by survival curve. Results:A total of 102 patients were included with a median follow-up of 695 (602, 923) days, during which 9 (8.8%) all-cause deaths and 33 (32.4%) composite end-point events occurred. Univariate Cox risk regression analysis found that TAC was a risk factor for all-cause mortality events in TAVI patients ( P=0.039), TAC and AVC were risk factors for composite endpoint events in TAVI patients ( P=0.047, 0.035).TAC was an independent predictor of all-cause mortality after TAVI in multivariate analysis ( HR=8.971, 95% CI 1.121-71.790, P=0.039), and TAC and AVC were independent risk factors for composite endpoint events after TAVI ( HR=2.243, 95% CI 1.099-4.578, P=0.026; HR=2.346, 95% CI 1.146-4.804, P=0.020). Kaplan-Meier survival curves showed that high TAC and AVC scores increased the risk of end-point events ( P<0.05). Conclusion:CT-quantified TAC and AVC volume scores are independent prognostic markers in TAVI patients, with greater calcification burden portending poorer clinical outcomes.

Objective To observe the value of artificial intelligence iterative reconstruction(AIIR)for low-dose chest CT images of infants with congenital heart disease.Methods Totally 262 infants with congenital heart disease who would undergo chest CT scanning were prospectively enrolled and randomly divided into low-dose group(n=142)and conventional dose group(n=120).Chest CT scanning with tube voltage of 80 kVp and tube current of 10 mAs was performed in low-dose group,and hybrid iterative reconstruction(HIR,group A)and AIIR(group B)were used to reconstruct images,respectively.In conventional dose group,chest CT scanning with tube voltage of 80 kVp and tube current of 100 mAs was performed,and HIR was used to reconstruct images(group C).Then subjective and objective evaluation on image quality were performed,the results were compared among 3 groups,and the value of AIIR was analyzed.Results Significant differences of image quality and clarity of displaying structures were found among 3 groups(all P＜0.001).Among them,except for the clarity of interlobar fissure,no significant difference of subjective scores was found between low-dose AIIR images and conventional dose HIR images(all corrected P＞0.05),while subjective scores of low-dose HIR images were all lower than those of low-dose AIIR images and conventional dose HIR images(all corrected P＜0.05).Significant differences of standard deviation(SD),signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)were found among 3 groups(all P＜0.001)and between each 2 groups(all corrected P＜0.05).The effective dose of low-dose group and conventional dose group was 0.09(0.08,0.10)and 0.85(0.75,1.03)mSv,respectively,and the former was lower than the latter(Z=-13.942,P＜0.001).Conclusion Using AIIR could obtain low-dose chest CT images of infants with quality comparable to conventional chest CT images.

CT is a commonly examination method in pediatric clinical practice.Formulating and popularizing low-dose pediatric CT scanning protocols and constructing a standard image quality evaluation system are the key directions of low-dose pediatric CT imaging.In recent years,domestic CT equipment achieved technological breakthroughs in hardware performance and image reconstruction algorithms,which could provide new paths for pediatric low-dose CT imaging in children combining with artificial intelligence technology.The current status of scanning protocols,the establishment of imaging quality evaluation system and the clinical promotion,as well as challenges of domestic CT in pediatric low-dose CT imaging were reviewed in this article.

Objective:To explore the clinical application value of MRI ultra-short echo time sequence (MRI-UTE) in the diagnosis of pulmonary nodules.Methods:This study was a cross-sectional study. A total of 101 consecutive patients were recruited prospectively from January to August 2024 at Huazhong Fuwai Hospital of Zhengzhou University. All of the included patients were diagnosed with pulmonary nodules by chest CT examination and intended for treatment. All patients underwent low-dose CT examination and MRI-UTE examination. The number, classification, and lung imaging reporting and data system (lung-RADS) grading of the pulmonary nodules were analyzed. Nodules classification was determined as solid nodules or sub-solid nodules, and sub-solid nodules included part-solid nodules and pure ground-glass nodules. Taking the evaluation results of radiologists with 10 and 12 years of experience in chest imaging diagnosis as the reference standard, the Kappa test was used to analyze the agreement of CT and MRI-UTE in terms of the accurate diagnosis, classification, and lung-RADS grading of pulmonary nodules. Results:Among the 101 patients, a total of 216 pulmonary nodules were identified. MRI-UTE accurately diagnosed 180 pulmonary nodules, while 203 pulmonary nodules were detected by CT. The concordance was moderate ( Kappa=0.48, P<0.001). In terms of nodule classification, CT correctly classified 167 nodules as solid and 36 as sub-solid, whereas MRI-UTE correctly classified 153 as solid and 23 as sub-solid, with good agreement (weighted Kappa=0.73, P<0.001). For lung-RADS grading, CT correctly graded 186 nodules, with 85 graded as category 2, 46 as category 3, 33 as category 4A, 12 as category 4B, and 10 as category 4X; MRI-UTE correctly graded 155 nodules, with 74 graded as category 2, 30 as category 3, 30 as category 4A, 12 as category 4B, and 9 as category 4X. The agreement between the two modalities in determining lung-RADS grade was also good (weighted Kappa=0.74, P<0.001). Conclusion:MRI-UTE demonstrates good agreement with CT in the accurate diagnosis, classification, and lung-RADS grading of pulmonary nodules, indicating certain clinical application value.

Objective:To assess the prognostic impact of the thoracic aorta and aortic valve calcification volume (TAC, AVC) score based on CT measurementsin patients undergoing transcatheter aortic valve implantation (TAVI).Methods:We retrospectively analyzed 102 patients who underwent TAVI for severe aortic stenosis from March 2018 to April 2022 at Fuwai Central China Cardiovascular Hospital. The patients were stratified into low TAC and AVC group (TAC low, AVC low) and high TAC and AVC group (TAC high, AVC high) based on median TAC and AVC. The independent risk factors affecting the prognosis of TAVI patients were analyzed using univariate and multivariate Cox proportional risk regression, and the independent risk factors affecting the prognosis of TAVI were analyzed by survival curve. Results:A total of 102 patients were included with a median follow-up of 695 (602, 923) days, during which 9 (8.8%) all-cause deaths and 33 (32.4%) composite end-point events occurred. Univariate Cox risk regression analysis found that TAC was a risk factor for all-cause mortality events in TAVI patients ( P=0.039), TAC and AVC were risk factors for composite endpoint events in TAVI patients ( P=0.047, 0.035).TAC was an independent predictor of all-cause mortality after TAVI in multivariate analysis ( HR=8.971, 95% CI 1.121-71.790, P=0.039), and TAC and AVC were independent risk factors for composite endpoint events after TAVI ( HR=2.243, 95% CI 1.099-4.578, P=0.026; HR=2.346, 95% CI 1.146-4.804, P=0.020). Kaplan-Meier survival curves showed that high TAC and AVC scores increased the risk of end-point events ( P<0.05). Conclusion:CT-quantified TAC and AVC volume scores are independent prognostic markers in TAVI patients, with greater calcification burden portending poorer clinical outcomes.

Objective To observe the value of artificial intelligence iterative reconstruction(AIIR)for low-dose chest CT images of infants with congenital heart disease.Methods Totally 262 infants with congenital heart disease who would undergo chest CT scanning were prospectively enrolled and randomly divided into low-dose group(n=142)and conventional dose group(n=120).Chest CT scanning with tube voltage of 80 kVp and tube current of 10 mAs was performed in low-dose group,and hybrid iterative reconstruction(HIR,group A)and AIIR(group B)were used to reconstruct images,respectively.In conventional dose group,chest CT scanning with tube voltage of 80 kVp and tube current of 100 mAs was performed,and HIR was used to reconstruct images(group C).Then subjective and objective evaluation on image quality were performed,the results were compared among 3 groups,and the value of AIIR was analyzed.Results Significant differences of image quality and clarity of displaying structures were found among 3 groups(all P＜0.001).Among them,except for the clarity of interlobar fissure,no significant difference of subjective scores was found between low-dose AIIR images and conventional dose HIR images(all corrected P＞0.05),while subjective scores of low-dose HIR images were all lower than those of low-dose AIIR images and conventional dose HIR images(all corrected P＜0.05).Significant differences of standard deviation(SD),signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)were found among 3 groups(all P＜0.001)and between each 2 groups(all corrected P＜0.05).The effective dose of low-dose group and conventional dose group was 0.09(0.08,0.10)and 0.85(0.75,1.03)mSv,respectively,and the former was lower than the latter(Z=-13.942,P＜0.001).Conclusion Using AIIR could obtain low-dose chest CT images of infants with quality comparable to conventional chest CT images.

CT is a commonly examination method in pediatric clinical practice.Formulating and popularizing low-dose pediatric CT scanning protocols and constructing a standard image quality evaluation system are the key directions of low-dose pediatric CT imaging.In recent years,domestic CT equipment achieved technological breakthroughs in hardware performance and image reconstruction algorithms,which could provide new paths for pediatric low-dose CT imaging in children combining with artificial intelligence technology.The current status of scanning protocols,the establishment of imaging quality evaluation system and the clinical promotion,as well as challenges of domestic CT in pediatric low-dose CT imaging were reviewed in this article.

Myocarditis has diverse clinical manifestations,which might develop into acute heart failure,cardiogenic shock and chronic dilated cardiomyopathy.Early diagnosis of myocarditis is crucial for improving prognosis.Cardiac MRI(CMRI)can display myocardial necrosis,fibrosis and edema,having become the best imaging method for evaluating myocarditis.The progresses in multi-parameter CMRI researches of acute myocarditis were reviewed in this article.

Objective To observe the value of cardiac MR(CMR)compressed sensing(CS)sequence and conventional movie(CM)sequence for evaluating biventricular function in patients with congenital heart disease(CHD).Methods A total of 71 patients with CHD,including 31 cases with regular heart rhythm(regular heart rhythm group)and 40 cases with arrhythmia(arrhythmia group)were prospectively collected and scanned with CM and CS sequences.The scanning time of 2 sequences were recorded,and subjective scores of imaging quality of 2 kinds of images were compared.The differences,consistency and correlation between quantitative parameters of biventricular function measured on 2 kinds of images were analyzed.Results The acquisition time of CS was(18.87±1.75)s,of CM was(147.56±5.23)s,which was shortened by 87.21％than CS.The quality of both 2 kinds of images met the diagnostic requirements.The subjective scores of CS images were lower than that of CM in regular heart rhythm group(4[3,5]vs.4[4,5],Z=-2.070,P=0.038),while of CS images were higher than that of CM images in arrhythmia group(4[4,4]vs.3[4,4],Z=-2.673,P=0.008).No significant difference of the left ventricular function parameters was detected obtained based on 2 kinds of images in all 71 cases,nor in regular heart rhythm group as well as in arrhythmia group(all P＞0.05).Meanwhile,the right ventricular(RV)end-diastolic volume index(EDVI)obtained based on CM and CS images were not significantly different(all P＞0.05),but significant differences of ejection fraction(EF),end-systolic volume index(ESVI)and stroke volume index(SVI)were found in all 71 cases,in regular heart rhythm group and in arrhythmia group(all P＜0.05).CMR parameters of biventricular function measured on CM and CS images were all consistent and positively correlated(all P＜0.05).Conclusion CS sequence could be used to accurately assess biventricular function of CHD patients,significantly improve imaging quality and shorten scanning time.