Objective To provide the administrative departments in the health sector with a method for estimating hospital beds when making regional health plans. Methods The method of general surveys was adopted to make relevant investigation on all the cities and districts in Shandong Province. Data collected were estimated by borrowed and self-developed formulas. Results By 2005, the total number of hospital beds in the province will be reduced by 5.19%, the number of beds in the city seats will be reduced by 4.97%, the number of beds in the county seats will be reduced by 1.03%, and the number of beds in the township seats will be reduced by 9.68%. Conclusion The findings of the study have filled in a gap at present when there is a lack of estimating methods. They are viable and yet still need to be polularized and perfected in practice.

Objective To investigate the factors associated with delay in decision to seek treatment in patients with acute myocardial infarction(AMI) in Beijing. Methods This prospective,cross-sectional,multicenter survey was conducted from November 1,2005 and December 31 ,2006. The participants consisted of 799 patients with STEMI admitted within 24 h of symptom onset to 19 hospitals in Beijing. Data were collected by semi-structured interviews and medical records review. The patients were categorized into an early decision group and the a late decision group based on the 30 min cut-off. Results The median(25%,75%) decision delay in STEMI patients was 60(20, 180)min. Factors associated with late decision in an univariate analysis were age ≥65 years, retirement or unemployment, history of myocardial infarction,symptom onset at home and intermittent symptoms, whereas presence of bystanders such as friends,coworkers or even strangers,unbearable symptoms,dyspnea,sweating,syncope and attribution of symptoms to cardiac origin were related to early decision. Multivariate logistic analysis showed that history of myocardial infarction,absence of syncope, intermittent symptoms,bearable symptoms and attribution of symptoms to noncardiac origin were independent predictors of decision delay＞30 min. Patients in the early decision group had more chances to receive acute reperfusion therapies(P=0.001) and shorter time intervals from symptom onset to reperfusion therapies(P＜0.001). Conclusions To a great extent patients with AMI in Beijing delayed in decision to seek treatment. History of myocardial infarction, symptom characteristics and symptom attribution were associated with decision delay.

Objective:To investigate the impact of artificial intelligence imaging optimization technique on the image quality and radiation dose of low-dose chest CT scan.Methods:Eighty patients who underwent chest CT examination in the Jilin University 1st hospital from July to August, 2019 were randomly divided into two groups(A, B), with 40 patients in each. The voltage of group A was 100 kV, while the other was 120 kV. According to different reconstruction method , group A was divided into two subgroups, group A1 and group A2. The images of A1 were reconstructed by iterative algorithm (ClearView 50%), while A2 images were optimized A1 by NeuAI imaging optimization technique. Group B used iterative algorithm (ClearView 50%) to reconstruct the image. The CT dose index (CTDI vol), dose-length product (DLP) and effective radiation dose ( E) of group A and group B were recorded and compared.Objective the evaluation indicators were CT noise (SD), signal-to-noise ratio (SNR) and comparative noise ratio (CNR) of ROI. Subjective evaluation was done by 2 chief radiologists using double-blind method and image quality was graded by 5-point Likert scale. Results:The patient characteristics between group A and group B showed no significant differences( P>0.05). Compared with group B, the effective radiation dose in group A was reduced by 72.1% [(1.48±0.49) mSv vs. (5.30±1.40) mSv]. The SD in group A1 was higher than that in group B, while SNR and CNR were lower ( ZSD=-4.24, ZSNR=-2.54, tCNR=-2.27, P<0.05). The SD in group A2 was significantly lower than that in group B ( ZSD=-28.24, P<0.001), and SNR and CNR were significantly higher than that in group B ( tSNR=-26.04, tCNR=-36.88, P<0.001). There was no significant difference in subjective scores of image noise between group A2 and group B, while subjective scores of lung structure in group B were better than those in group A2( χ2=4.96、7.04, P<0.05). Conclusions:Although the radiation dose was reduced by 72.1%, the low-dose chest CT images optimized by AI could reach the image quality level of standard dose.

Objective:To investigate the value of the virtual monoenergetic image (VMI) obtained by a new dual-layer detector spectral CT combined with metal artifact reduction algorithms(O-MAR) in reduction of different types of artifacts caused by 125I seeds implantation and in improvement of the post-operative CT image quality. Methods:This was a cross-sectional study. Thirty-five patients who underwent dual-layer detector spectral CT scanning of the chest and abdomen after 125I seeds implantation were retrospectively included at the First Affiliated Hospital of Zhengzhou University from March to September 2022. The spectral data were collected and reconstructed into conventional CT image (CI), VMI image (50-150 keV, 20 keV/level), CI+O-MAR image, and VMI+O-MAR image (50-150 keV, 20 keV/level). The artifacts′ removal effects and image quality improvement in each group were evaluated. Two slices with the strongest artifacts were selected for analysis for each patient, resulting in a total of 70 slices. Objective indicators including artifact index (AI), signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of soft tissue regions affected by artifacts were measured and calculated. Subjective indicators including the overcorrected artifacts and new artifacts, the different forms of artifacts, the diagnosis of artifacts, and the image quality were assessed. One-way analysis of variance was used for comparisons among multiple groups. Paired t test was used to compare the quantitative indicators between the combined O-MAR group and the non-O-MAR group. Kappa statistics was used to evaluate the consistency between observers. Results:In high/low-density artifacts (ROI H/L), the AI values in all groups showed decrease with increasing VMI keV. In artifact-affected tissue (ROI T), SNR of the CI/VMI (70-150 keV)+O-MAR group were significantly higher than those of the CI/VMI group ( P<0.05), CNR of the CI/VMI(50-150 keV)+O-MAR group were significantly higher than those of the CI/VMI group ( P<0.05). Both overcorrection and new artifacts mainly presented in VMI 50 keV and VMI 70 keV groups; Compared with VMI (50-70 keV) group, significantly less numbers of overcorrection and new artifacts were found in VMI (50-70 keV)+O-MAR group ( P<0.05); regarding the comparison of artifact types, with the VMI keV increasing, the number of a-type banded artifacts gradually decreased on images with high-density artifacts, reaching a minimum of 3 in the VMI 150 keV+O-MAR group; while the number of e-type artifacts with little or no artifacts increased, with the highest number of 23 in the VMI 150 keV+O-MAR group. The total number of high-density artifacts in each type decreased with increasing VMI keV. As VMI keV increased, the diagnostic and image quality scores of high-density artifacts in each group were significantly higher than those of low-density artifacts in the VMI+O-MAR group ( P<0.05). Conclusions:VMI combined with O-MAR can significantly improve the objective and subjective image quality of follow-up CT imaging after 125I seed implantation, enhancing lesion visibility and diagnostic confidence. Additionally, VMI+O-MAR showed more pronounced correction effect on high-density artifacts.

Objective:To explore the clinical value of quantitative parameters on spectral CT in predicting the invasiveness of lung adenocarcinoma manifesting as ground-glass nodules (GGN).Methods:The clinical and imaging data of 129 patients with pathologically confirmed lung adenocarcinoma who were surgically resected in the First Affiliated Hospital of Zhengzhou University from March to October 2022 were retrospectively analyzed, including 45 males and 84 females, aged from 33 to 81. According to the pathological results, they were divided into the minimally invasive adenocarcinoma (MIA) group ( n=64) and the invasive adenocarcinoma (IAC) group ( n=65). All patients underwent enhanced spectral CT within two weeks before surgery. The iodine density map, Z-Effective (Z eff) map, and electron density (ED) map were reconstructed on the post-processing workstation, and the spectral parameters, including normalized iodine concentration (NIC), arterial enhancement fraction (AEF), Z eff, and ED were measured and calculated. Conventional CT features were analyzed, including maximum diameter, CT value, nodule types, margin, lobulation sign, spiculation sign, bubble sign, pleural retraction sign, abnormal vascular sign, and air bronchial sign. The clinical features, conventional CT characteristics and spectral CT parameters of two groups were compared using the independent sample t test, the Mann-Whitney U test, and the χ 2 test. Multivariate logistic regression analysis was used to evaluate the independent risk factors of lung adenocarcinoma invasiveness, and the model was constructed. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the performance of parameters and models in predicting the invasiveness of lung adenocarcinoma. Results:There were significant differences between the MIA group and IAC group in maximum diameter, CT value, nodule type, margin, spiculation sign, pleural retraction sign, air bronchial sign, venous phase NIC, AEF, venous phase Z eff, arterial phase ED, venous phase ED ( P<0.05). Multivariate logistic regression analysis showed that the maximum diameter (OR=1.183, 95%CI 1.062-1.318), CT value (OR=1.004, 95%CI 1.001-1.007), venous phase NIC (OR=1.185, 95%CI 1.083-1.298), AEF(OR=0.975, 95%CI 0.957-0.994), venous phase Z eff (OR=0.031, 95%CI 0.005-0.196) were independent influence factors for the invasiveness of lung adenocarcinoma. The conventional CT model was established with the maximum diameter and CT value, and the spectral CT model was established with venous phase NIC, AEF, and venous phase Z eff. The combined model was established with all the parameters above. Areas under the ROC curve of the conventional CT model, the spectral CT model, and the combined model for predicting the invasiveness of lung adenocarcinoma were 0.828, 0.854, and 0.902, respectively. Conclusion:The quantitative parameters of double-layer detector spectral CT can be used as an indicator to predict the invasiveness of lung adenocarcinoma manifesting as GGN, and AEF has the highest diagnostic efficacy. Spectral CT combined with conventional CT features can further improve the diagnostic efficiency.

Objective:To investigate the benefits of artificial intelligence (AI)-based image optimization technique on image quality of coronary CT angiography (CCTA).Methods:Sixty patients, who were referred for CCTA, were prospectively enrolled between May and June 2018 in Peking Union Medical College Hospital and were randomly divided into two groups. Group A was scanned with a low tube voltage of 80 kVp and a reduced contrast media volume of lopamiro at 0.7 ml /kg and group B was scanned with a standard 120 kVp tube voltage and an injection of 70 ml lopamiro. According to the different reconstruction methods, group A was divided into two subgroups. The images of group A1 were reconstructed with iterative reconstruction (IR). IR and further AI-based image optimization were used in group A2. Group B was also reconstructed by IR. To evaluate image quality objectively, the mean attenuation of contrast-enhancement values, background noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured and calculated in the region of interests (ROIs) of the aortic root (Ao), left main coronary artery (LM), left anterior descending branch (LAD), left circumflex branch (LCX) and right coronary artery (RCA), respectively. In addition, the subjective evaluation was performed by two radiologists using Likert 4 scale (1 for excellent and 4 for poor) to evaluate the image quality of coronary artery branches and segments. The estimated radiation dose in terms of volume CT dose index (CTDI vol), dose length product (DLP) and effective dose (ED) was recorded and compared between group A and group B. Analyses of the differences between groups were compared with image quality, radiation dose by t test or Wilcoxon signed ranks test, and subjective assessments were compares with χ 2 test. Results:In terms of lumen enhancement, compared to group A2, there was no significant difference in CT value of each ROI ( P>0.05); CT value of group A1 and group A2 at Ao was significantly higher than that of group B ( P<0.01), but there was no significant difference in other ROI ( P>0.05). By comparing noise, SNR and CNR, it could be seen that compared to group B, A2 group optimized by AI had a significantly lower noise level at Ao than group B ( P<0.001), and there was no statistical difference in ROI for the rest (all P>0.05).SNR at Ao was significantly higher than that of group B ( P<0.001), and there was no statistical difference in ROI for the rest ( P>0.05).However, the CNR of group A2 was significantly higher than that of group B in all ROI ( P<0.001). Compared to the AI-optimized A2 group, the noise of A2 group was significantly lower than that of A1 group at all ROI, and SNR and CNR were significantly higher than that of A1 group ( P<0.001). The subjective evaluation results of coronary segments showed that image quality of group A2 and group B was significantly better than that of group A1 ( P=0.002,0.038). There was no significant difference between group A2 and group B ( P=0.543). The radiation dose indexes of CTDI vol, DLP and ED in group A were significantly lower than those in group B (all P<0.001). The ED was decreased by 70.4%. Meanwhile, the volume of contrast media in group A was reduced by 37.1% than that that in group B. Conclusion:Compared to conventional scanning, CCTA images optimized by AI technology improved subjective and objective image quality.

To explore the basics of integrated curriculums and the reform plan of integrated organ-system based curriculum of clinical subjects, this paper takes the integrated musculoskeletal system based curriculum in the third semester for undergraduates majoring in clinical medicine as an example, elaborates on the following five aspects: the organ system-centered curriculum system, the integration of teaching content, curriculum implementation plans, curriculum advantages, major issues and measures for improvement. This paper puts forward some urgent problems such as writing teaching materials, changing teachers' traditional teaching concepts, arranging the course reasonably, achieving learning outcomes, and deepening the integration of knowledge in various subjects. It is also provides suggestions for building a coherent and complete teaching model and knowledge system of the integrated organ-system based curriculum, helping students better understand the organic relationships between various disciplines, and promoting the curriculum reform. The reform of the integrated organ-system based curriculum has achieved initial results.