Objective To explore the solution of local water-fat separation swap artifacts(WFS-SA)on nasopharyngeal T1WI-itera-tive decomposition of water and fat with echo asymmetry and least-squares estimation(T1WI-IDEAL)enhanced examination images.Methods Thirty-seven patients with obvious WFS-SA on nasopharyngeal enhanced examination using the A group T1WI-IDEAL param-eters were collected.Scans with modified parameters B,C,and D groups were subsequently performed based on the A group parame-ters.Subjective ratings of image quality were conducted on the four image groups,and the image signal-to-noise ratio(SNR)of the posterior wall of the nasopharynx and medulla oblongata was quantified.The total number of artifact slices(TAS),total artifact area(TAA),and maximum single-slice artifact area(SSAAmax)of the WFS-SA in the four image groups were recorded.The consistency of image quality ratings between the two technologists was analyzed via the intraclass correlation coefficient(ICC),and one-way analysis of variance or rank-sum test was used to compare the SNR,TAS,TAA,and SSAAmax among the four image groups.Results The subjective rating for modified B,C,and D groups of T1WI-IDEAL images by two technologists was deemed satisfactory(ICC=0.721-0.928,P<0.001).Significant variations in image quality ratings were observed among the three groups(H=45.131,P<0.001),with ratings for C and D groups surpass-ing those for B group(P<0.001).The TAS,TAA,and SSAAmax exhibited a decreasing pattern on T1WI-IDEAL images across A,B,C,and D groups,with statistically significant variances observed among all groups(P<0.001).Moreover,the SNR of the medulla oblongata layer in D group displayed a notably higher value compared to A,B groups,with statistically significant distinctions(P<0.001).Conclusion By combining the reduction of the echo train length(ETL)to 2 with the implementation of a double shimming,the occurrence of WFS-SA on nasopharyngeal T1WI-IDEAL enhanced examination images can be minimized and the overall image quality can be enhanced.

Objective:To explore the value of the vesical imaging-reporting and data system (VI-RADS) score based on multiparametric MRI (mpMRI) combined with quantitative tumor MRI parameters in assessing the muscle invasion of bladder cancer.Methods:The study was a case-control study. The data of 87 bladder cancer patients confirmed by pathology who underwent mpMRI of the bladder were retrospectively collected from the First Medical Center of Chinese PLA General Hospital between January 2019 and April 2023 The pathological findings were used as the gold standard to categorize them into the muscle invasive bladder cancer (MIBC) group (29 cases) and non-muscle invasive bladder cancer (NMIBC) group (58 cases). Quantitative parameters were measured based on preoperative mpMRI images, including the length of tumor bladder wall contact, the perpendicular distance between the bladder tumor and the tangent of the bladder wall, the maximal diameter of the bladder tumor, and the volume of the bladder tumor. Bladder cancer was classified according to the VI-RADS scoring criteria. The Mann-Whitney U test was used for intergroup comparisons. Multivariate logistic regression analysis was performed to obtain the independent risk factors related to muscle invasion of bladder cancer and to establish the model. The receiver operating characteristic curves were analyzed for MRI quantitative parameters and logistic regression models, and area under the curve (AUC) comparisons were performed using the DeLong test. Results:The differences in tumor bladder wall contact length, perpendicular distance from the tumor to the tangent line of the bladder wall, maximum diameter, bladder tumor volume, and the VI-RADS scores were statistically significant between the MIBC group and the NMIBC group ( P<0.05). Multifactorial logistic regression analysis showed that tumor bladder wall contact length ( OR=21.07, 95% CI 3.56-124.89, P=0.001) and VI-RADS score ( OR=11.90, 95% CI 3.53-40.12, P<0.001) were the independent risk factors for evaluating the muscle invasion of bladder cancer. The difference between the VI-RADS score and the tumor bladder wall contact length for assessing muscular infiltration of bladder cancer had AUCs of 0.802 (95% CI 0.704-0.899) and 0.759 (95% CI 0.652-0.865). The combined model of VI-RADS score combined with tumor bladder wall contact length had an AUC of 0.891 (95% CI 0.812-0.970), which was higher than the diagnostic efficacy of applying tumor bladder wall contact length or VI-RADS score alone ( Z=3.05, 2.37, P=0.002, 0.018). Conclusion:Tumor contact length with the bladder wall is an independent risk factor for assessing muscle invasion of bladder cancer and the combination of VI-RADS score may enhances diagnostic accuracy.

Purpose To investigate the application value of MRI in distinguishing Association Research Circulation Osseous(ARCO)stage II and IIIA of osteonecrosis of the femoral head.Materials and Methods A total of 48 patients with ARCO stage II/IIIA non-traumatic osteonecrosis of the femoral head in the Fourth Medical Center of Chinese PLA General Hospital from October 2022 to September 2023 were retrospectively included,with a total of 75 hips.The hips were divided into ARCO stage II group(26 hips)and stage IIIA group(49 hips)based on CT.The MRI findings(including irregular articular surface of femoral head,similar closed-loop shape of necrotic-viable interface,fibrous granulation tissue and cystic change in necrotic area,perinecrotic bone marrow edema,articular effusion and synovitis)were compared between the two groups,and the diagnostic efficiencies were evaluated.Results Irregular articular surface of femoral head,cystic change and fibrous granulation tissue in necrotic area and synovitis were more common in stage IIIA group than in stage II group,the range of bone marrow edema was larger than that in stage II group,the grade of articular effusion was larger than that in stage II group,and similar closed-loop shape of the necrotic-viable interface was found in stage II group,but no such sign was found in stage IIIA group,with statistical difference of all the above(χ2/Z=-5.727-54.764,all P<0.001).The area under the curve of irregular articular surface of femoral head,bone marrow edema,synovitis,articular effusion,fibrous granulation tissue in necrotic area,cystic change in the necrotic area,and similar closed-loop shape of the necrotic-viable interface in distinguishing ARCO stage II and IIIA were 0.931,0.891,0.845,0.799,0.772,0.724 and 0.692,respectively.The diagnostic efficiency of irregular articular surface of femoral head was not statistically significant with bone marrow edema and synovitis(both P>0.05),and higher than articular effusion,fibrous granulation tissue in necrotic area,cystic change in necrotic area,and similar closed-loop shape of the necrotic-viable interface(Z=2.054,2.711,4.182,4.003,all P<0.05).Conclusion MRI is helpful to distinguish ARCO stage II from stage IIIA of osteonecrosis of the femoral head.The diagnostic efficiencies of irregular articular surface of femoral head,bone marrow edema and synovitis are higher.

Objective To explore the solution of local water-fat separation swap artifacts(WFS-SA)on nasopharyngeal T1WI-itera-tive decomposition of water and fat with echo asymmetry and least-squares estimation(T1WI-IDEAL)enhanced examination images.Methods Thirty-seven patients with obvious WFS-SA on nasopharyngeal enhanced examination using the A group T1WI-IDEAL param-eters were collected.Scans with modified parameters B,C,and D groups were subsequently performed based on the A group parame-ters.Subjective ratings of image quality were conducted on the four image groups,and the image signal-to-noise ratio(SNR)of the posterior wall of the nasopharynx and medulla oblongata was quantified.The total number of artifact slices(TAS),total artifact area(TAA),and maximum single-slice artifact area(SSAAmax)of the WFS-SA in the four image groups were recorded.The consistency of image quality ratings between the two technologists was analyzed via the intraclass correlation coefficient(ICC),and one-way analysis of variance or rank-sum test was used to compare the SNR,TAS,TAA,and SSAAmax among the four image groups.Results The subjective rating for modified B,C,and D groups of T1WI-IDEAL images by two technologists was deemed satisfactory(ICC=0.721-0.928,P<0.001).Significant variations in image quality ratings were observed among the three groups(H=45.131,P<0.001),with ratings for C and D groups surpass-ing those for B group(P<0.001).The TAS,TAA,and SSAAmax exhibited a decreasing pattern on T1WI-IDEAL images across A,B,C,and D groups,with statistically significant variances observed among all groups(P<0.001).Moreover,the SNR of the medulla oblongata layer in D group displayed a notably higher value compared to A,B groups,with statistically significant distinctions(P<0.001).Conclusion By combining the reduction of the echo train length(ETL)to 2 with the implementation of a double shimming,the occurrence of WFS-SA on nasopharyngeal T1WI-IDEAL enhanced examination images can be minimized and the overall image quality can be enhanced.

Purpose To investigate the application value of MRI in distinguishing Association Research Circulation Osseous(ARCO)stage II and IIIA of osteonecrosis of the femoral head.Materials and Methods A total of 48 patients with ARCO stage II/IIIA non-traumatic osteonecrosis of the femoral head in the Fourth Medical Center of Chinese PLA General Hospital from October 2022 to September 2023 were retrospectively included,with a total of 75 hips.The hips were divided into ARCO stage II group(26 hips)and stage IIIA group(49 hips)based on CT.The MRI findings(including irregular articular surface of femoral head,similar closed-loop shape of necrotic-viable interface,fibrous granulation tissue and cystic change in necrotic area,perinecrotic bone marrow edema,articular effusion and synovitis)were compared between the two groups,and the diagnostic efficiencies were evaluated.Results Irregular articular surface of femoral head,cystic change and fibrous granulation tissue in necrotic area and synovitis were more common in stage IIIA group than in stage II group,the range of bone marrow edema was larger than that in stage II group,the grade of articular effusion was larger than that in stage II group,and similar closed-loop shape of the necrotic-viable interface was found in stage II group,but no such sign was found in stage IIIA group,with statistical difference of all the above(χ2/Z=-5.727-54.764,all P<0.001).The area under the curve of irregular articular surface of femoral head,bone marrow edema,synovitis,articular effusion,fibrous granulation tissue in necrotic area,cystic change in the necrotic area,and similar closed-loop shape of the necrotic-viable interface in distinguishing ARCO stage II and IIIA were 0.931,0.891,0.845,0.799,0.772,0.724 and 0.692,respectively.The diagnostic efficiency of irregular articular surface of femoral head was not statistically significant with bone marrow edema and synovitis(both P>0.05),and higher than articular effusion,fibrous granulation tissue in necrotic area,cystic change in necrotic area,and similar closed-loop shape of the necrotic-viable interface(Z=2.054,2.711,4.182,4.003,all P<0.05).Conclusion MRI is helpful to distinguish ARCO stage II from stage IIIA of osteonecrosis of the femoral head.The diagnostic efficiencies of irregular articular surface of femoral head,bone marrow edema and synovitis are higher.

Objective:To explore the value of the vesical imaging-reporting and data system (VI-RADS) score based on multiparametric MRI (mpMRI) combined with quantitative tumor MRI parameters in assessing the muscle invasion of bladder cancer.Methods:The study was a case-control study. The data of 87 bladder cancer patients confirmed by pathology who underwent mpMRI of the bladder were retrospectively collected from the First Medical Center of Chinese PLA General Hospital between January 2019 and April 2023 The pathological findings were used as the gold standard to categorize them into the muscle invasive bladder cancer (MIBC) group (29 cases) and non-muscle invasive bladder cancer (NMIBC) group (58 cases). Quantitative parameters were measured based on preoperative mpMRI images, including the length of tumor bladder wall contact, the perpendicular distance between the bladder tumor and the tangent of the bladder wall, the maximal diameter of the bladder tumor, and the volume of the bladder tumor. Bladder cancer was classified according to the VI-RADS scoring criteria. The Mann-Whitney U test was used for intergroup comparisons. Multivariate logistic regression analysis was performed to obtain the independent risk factors related to muscle invasion of bladder cancer and to establish the model. The receiver operating characteristic curves were analyzed for MRI quantitative parameters and logistic regression models, and area under the curve (AUC) comparisons were performed using the DeLong test. Results:The differences in tumor bladder wall contact length, perpendicular distance from the tumor to the tangent line of the bladder wall, maximum diameter, bladder tumor volume, and the VI-RADS scores were statistically significant between the MIBC group and the NMIBC group ( P<0.05). Multifactorial logistic regression analysis showed that tumor bladder wall contact length ( OR=21.07, 95% CI 3.56-124.89, P=0.001) and VI-RADS score ( OR=11.90, 95% CI 3.53-40.12, P<0.001) were the independent risk factors for evaluating the muscle invasion of bladder cancer. The difference between the VI-RADS score and the tumor bladder wall contact length for assessing muscular infiltration of bladder cancer had AUCs of 0.802 (95% CI 0.704-0.899) and 0.759 (95% CI 0.652-0.865). The combined model of VI-RADS score combined with tumor bladder wall contact length had an AUC of 0.891 (95% CI 0.812-0.970), which was higher than the diagnostic efficacy of applying tumor bladder wall contact length or VI-RADS score alone ( Z=3.05, 2.37, P=0.002, 0.018). Conclusion:Tumor contact length with the bladder wall is an independent risk factor for assessing muscle invasion of bladder cancer and the combination of VI-RADS score may enhances diagnostic accuracy.

Objective To analyze the prevalence of chronic diseases and its influencing factors of dust-exposed male workers in a coal mine. Methods A total of 9 782 dust-exposed male workers from a coal mine in Shanxi Province were selected as the study subjects using the purposive sampling method. Their occupational health examination results were collected to analyze the prevalence of chronic diseases and its influencing factors. Results The prevalence of dyslipidemia, hyperuricemia, hypertension and diabetes were 40.3%, 30.7%, 23.5% and 5.6%, respectively. The prevalence of chronic diseases was 64.8%. Among them, the prevalence of having one, two, three or more chronic diseases were 36.5%, 21.6% and 6.7%, respectively. The prevalence of comorbid chronic diseases was 28.3%, with the highest prevalence of concurrent dyslipidemia and hyperuricemia of 11.0%. The results of binary logistic regression analysis showed that the risk of chronic disease was higher in workers <40 years old, smoking, overweight, obesity and total working years >20 years (all P<0.05). The results of multinomial logistic regression analysis showed that workers <40 years old, overweight, obesity and total working years >20 years were risk factors for having one chronic disease (all P<0.05). The workers <40 years old, smoking, overweight, obesity and total working years >20 years were risk factors for having two chronic diseases (all P<0.05). The workers <40 years old, smoking, alcohol consumption, overweight, obesity, other types of work, and working years >20 years were risk factors for having three or more chronic diseases (all P<0.05). Conclusion The prevalence of chronic diseases is high and the comorbidity of chronic diseases is common among dust-exposed male workers. The main influencing factors were age, smoking, alcohol consumption, overweight, obesity, type of work, and working year. Workers with more contributing factors have higher risk of chronic comorbidities.

The accurate assessment of burn injuries is complex and difficult. The emergence of some new skin imaging techniques, such as hyperspectral imaging, unilateral magnetic resonance imaging, laser Doppler perfusion imaging, etc., has made great progress in research on burn injury assessment. With the continuous progress of imaging technology and medical imaging, medical imaging technologies such as digital radiography, computed tomography, magnetic resonance imaging, and ultrasonography, and so on, have played an important role in burn injury assessment. However, there are still relatively few research reports on burn injury imaging, which may be due to the fact that the imaging techniques and diagnostic experience used for burn injury assessment are not yet fully popular in some medical institutions, and the imaging manifestations related to burns are complex and lack of specificity. This article mainly reviews the application research progress of various imaging techniques in the assessment of burn injury in recent years, aiming to explore the application value of various imaging techniques in burn injury assessment.

Objective: To prospectively compare single-shot (SS) echo-planar imaging (EPI) and field-of-view optimized and constrained undistorted single-shot multiplexed sensitivity-encoding (FOCUS MUSE) for diffusion-weighted imaging (DWI) in evaluating thyroid-associated ophthalmopathy (TAO). Materials and Methods: SS EPI and FOCUS MUSE DWIs were obtained from 39 patients with TAO (18 male; mean ± standard deviation: 48.3 ± 13.3 years) and 26 healthy controls (9 male; mean ± standard deviation: 43.0 ± 18.5 years). Two radiologists scored the visual image quality using a 4-point Likert scale. The image quality score, signal-to-noise ratio (SNR), contrast-tonoise ratio (CNR), and apparent diffusion coefficient (ADC) of extraocular muscles (EOMs) were compared between the two DWIs. Differences in the ADC of EOMs were also evaluated. The performance of discriminating active from inactive TAO was assessed using receiver operating characteristic curves. The correlation between ADC and clinical activity score (CAS) was analyzed using Spearman correlation. Results: Compared with SS EPI DWI, FOCUS MUSE DWI demonstrated significantly higher image quality scores (P < 0.001), a higher SNR and CNR on the lateral rectus muscle (LRM) and medial rectus muscle (MRM) (P < 0.05), and a non-significant difference in the ADC of the LRM and MRM. Active TAO showed higher ADC than inactive TAO and healthy controls with both SS EPI and FOCUS MUSE DWIs (P < 0.001). Inactive TAO and healthy controls did not show a significant ADC difference with both DWIs. Compared with SS EPI DWI, FOCUS MUSE DWI demonstrated better discrimination of active from inactive TAO (AUC:0.925 vs. 0.779; P = 0.007). The ADC was significantly correlated with CAS in SS EPI DWI (r = 0.391, P < 0.001) and FOCUS MUSE DWI (r = 0.645, P < 0.001). Conclusion FOCUS MUSE DWI provides better images for evaluating EOMs and better performance in diagnosing active TAO than SS EPI DWI. The application of FOCUS MUSE will facilitate the DWI evaluation of TAO.

Objective:To construct a model for predicting early recurrence of hepatocellular carcinoma (HCC) patients after radiofrequency ablation by different machine learning models based on multimodal MRI and clinical indicators, and to evaluate the predictive efficacy of the model.Methods:The data of patients with HCC who underwent radiofrequency ablation in Fourth Medical Center of Chinese PLA General Hospital and the First Medical Center of Chinese PLA General Hospital from January 2015 to December 2021 were retrospectively analyzed. A total of 169 patients with HCC were enrolled, including 152 males and 17 females, aged (57.2±9.2) years. The training set ( n=135) and the test set ( n=34) were randomly divided according to 8∶2. There were 49 cases recurrence in training set and 12 cases recurrence in test set. Based on the training set, the clinical influencing factors of early recurrence in patients with HCC after radiofrequency ablation were screened by univariated and multivariate logistic analysis, and the imaging features were sequentially screened by variance threshold method, select K-best and LASSO regression. Support vector machine (SVM), logistic regression and random forest (RFOREST) were used to construct the prediction models of early postoperative recurrence with simple imagomics alone or combined clinical features, respectively, and the receiver operating characteristic (ROC) curve was used to evaluate the prediction efficiency of the models. Results:Multivariate logistic regression analysis showed that preoperative alpha-fetoprotein >20 μg/L, platelet count >140×10 9 and tumor location were the influential factors for early recurrence of HCC patients after radiofrequency ablation (all P<0.05). Through variance threshold analysis, select K-best and LASSO regression, 16 optimal image omics features were selected. SVM, logistic regression and RFOREST were used to construct a simple imaging omics model for predicting early recurrence of HCC patients after radiofrequency ablation. The areas under ROC curve of the test set were 0.826, 0.830 and 0.826, respectively. And the areas under ROC curve of the constructed imagomics combined clinical model of test set were 0.830, 0.830 and 0.909, respectively. The area under ROC curve of RFOREST in the test set was better than that of SVM and logistic regression ( Z=2.19, 3.98, P=0.008, 0.008). Conclusion:The combined model constructed by SVM, logistic regression and RFOREST based on clinical indicators and image omics features is effective in predicting the early recurrence of patients with HCC after radiofrequency ablation, and the model constructed by RFOREST is the best.