Objective To evaluate the accuracy of multiparametric imaging on the dual-source CT through acceptance and commissioning testing, and to provide a reference for standardized clinical application. Methods Both the adult and pediatric dual-source CT scanning modes were used to scan the electron density phantom, and identical multiparametric image reconstruction tasks were performed, including the conventional CT images, the mixed CT images, the virtual monoenergetic images, the iodine images, the electron density images, and the effective atomic number images. Results In the adult scanning mode, the virtual monoenergetic CT numbers showed the greatest difference for the cortical bone (1722 HU at 40 keV vs. 30 HU at 80 keV), with smaller differences observed for other materials as their atomic numbers decreased. The pediatric scanning mode exhibited a similar trend, with the largest difference occurring at 40 keV (1393 HU). In the adult scanning mode, the deviations between the theoretical and measured iodine concentration values were all within 5%, whereas in the pediatric scanning mode, the largest deviation was 15% for an iodine concentration of 2.0 mg/mL. For the electron density, the largest deviation between the theoretical and measured values occurred in the LN450 lung (9.18% in the adult scanning mode and 8.96% in the pediatric scanning mode); the deviations for the LN300 lung were all below 7.2%, for aluminum below 6.3%, and for other tissues within 3%. For the effective atomic number, the deviations between the theoretical and measured values were all within 5% in both scanning modes. Conclusion To ensure the accuracy and reproducibility of the dual-source CT applications, a comprehensive acceptance testing protocol should be established to guarantee the safety and precision of the CT localization process.

Objective:To investigate the impact of chromate exposure on pulmonary function indices in occupational populations and explore the potential role of alterations in inflammatory indicators in this process.Methods:In July 2024, A cross-sectional analysis was conducted using occupational health examination data of 30875 workers from chromate-related enterprises in Jiangsu Province in 2020 and 2021. Based on the occupational positions and whether there is chromium acid salt exposure in the occupational hazards of the research subjects over the years, they are divided into chromium acid salt exposure group and non-exposure group. For those exposed to chromium acid salts, based on job position descriptions and duration of chromium acid salt exposure, they are further categorized into intermittent exposure group and continuous exposure group; among them, the actual exposure time in the intermittent exposure group is less than half of the working shift time, and the exposure duration is less than the total working life. Pulmonary function test indicators include forced vital capacity (forced vital capacity, FVC) %, first-second forced expiratory volume (forced expiratory volume in one second, FEV 1.0) %, and the ratio of first-second forced expiratory volume to forced vital capacity (FEV 1.0/FVC) %. Peripheral blood samples from the upper limbs of the research subjects were collected on an empty stomach for routine blood tests, selecting neutrophil count, platelet count, and lymphocyte count results, calculating the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). Quantitative data that meet normal distribution are expressed using Mean±SD, while variables that do not meet normal distribution are represented by M ( Q1, Q3). Categorical data are expressed using frequency or proportion (%). Linear variable comparisons between groups use t-tests. Generalized linear models were employed to assess the correlation between chromate exposure and pulmonary function indices, while mixed regression models were utilized to explore potential underlying effects. Results:Compared with the non-exposed group, the pulmonary function indices FVC (%), FEV 1.0/FVC (%), and FEV 1.0 (%) in the chromate-exposed group showed a decreasing trend ( P<0.01), indicating statistically significant differences. As the frequency of chromate exposure increased, the prevalence of pulmonary dysfunction rose. The prevalence rates of obstructive, restrictive, and mixed respiratory dysfunction among the chromate-exposed population (including intermittent exposure and continuous exposure groups) were 0.26%, 4.67%, and 0.12%, which were higher than those in the non-exposed group (0.09%, 0.84%, and 0.07%, respectively). All these differences were statistically significant ( P<0.05). After stratification by gender, a negative correlation was observed between chromate exposure and the inflammatory indicator platelet-to-lymphocyte ratio (PLR) ( P<0.05). Potential effect analysis revealed that PLR played a certain mediating role between chromate exposure and the decline in pulmonary function indices, with a mediating proportion of 2.2%. Conclusion:Chromate exposure in occupational populations may lead to a decline in pulmonary ventilatory function and alterations in peripheral blood inflammatory indicators. Inflammatory indicators may be involved in the pulmonary function decline caused by chromate exposure.

Objective:By systematically evaluate the implementation of GBZ 2.1, so as to provide technical basis for the future revisions of this standard.Methods:From May to October 2023, Based on the pre survey questionnaire, the semi-structured interview method was used to interviews with experts from CDC, Occupational disease prevention and control hospital institutes, employers, occupational hygiene technical service intermediaries and universities, and the inductive method was used to extract the topics and relevant suggestions.Results:Generally, GBZ 2.1 is scientific, practical, progressiveness and operable. There are still some issues such as OELs overlapping and the correspondence between Chinese and English names. The outstanding problem is the coordination with other standard contents.Conclusion:The technical indicators in GBZ 2.1 could adapt to the needs of current practical work. The coordination between standards needs to be clarified, and the new recommended content needs further promotion and exploration on how to implement it.

Objective:To investigate the impact of chromate exposure on pulmonary function indices in occupational populations and explore the potential role of alterations in inflammatory indicators in this process.Methods:In July 2024, A cross-sectional analysis was conducted using occupational health examination data of 30875 workers from chromate-related enterprises in Jiangsu Province in 2020 and 2021. Based on the occupational positions and whether there is chromium acid salt exposure in the occupational hazards of the research subjects over the years, they are divided into chromium acid salt exposure group and non-exposure group. For those exposed to chromium acid salts, based on job position descriptions and duration of chromium acid salt exposure, they are further categorized into intermittent exposure group and continuous exposure group; among them, the actual exposure time in the intermittent exposure group is less than half of the working shift time, and the exposure duration is less than the total working life. Pulmonary function test indicators include forced vital capacity (forced vital capacity, FVC) %, first-second forced expiratory volume (forced expiratory volume in one second, FEV 1.0) %, and the ratio of first-second forced expiratory volume to forced vital capacity (FEV 1.0/FVC) %. Peripheral blood samples from the upper limbs of the research subjects were collected on an empty stomach for routine blood tests, selecting neutrophil count, platelet count, and lymphocyte count results, calculating the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). Quantitative data that meet normal distribution are expressed using Mean±SD, while variables that do not meet normal distribution are represented by M ( Q1, Q3). Categorical data are expressed using frequency or proportion (%). Linear variable comparisons between groups use t-tests. Generalized linear models were employed to assess the correlation between chromate exposure and pulmonary function indices, while mixed regression models were utilized to explore potential underlying effects. Results:Compared with the non-exposed group, the pulmonary function indices FVC (%), FEV 1.0/FVC (%), and FEV 1.0 (%) in the chromate-exposed group showed a decreasing trend ( P<0.01), indicating statistically significant differences. As the frequency of chromate exposure increased, the prevalence of pulmonary dysfunction rose. The prevalence rates of obstructive, restrictive, and mixed respiratory dysfunction among the chromate-exposed population (including intermittent exposure and continuous exposure groups) were 0.26%, 4.67%, and 0.12%, which were higher than those in the non-exposed group (0.09%, 0.84%, and 0.07%, respectively). All these differences were statistically significant ( P<0.05). After stratification by gender, a negative correlation was observed between chromate exposure and the inflammatory indicator platelet-to-lymphocyte ratio (PLR) ( P<0.05). Potential effect analysis revealed that PLR played a certain mediating role between chromate exposure and the decline in pulmonary function indices, with a mediating proportion of 2.2%. Conclusion:Chromate exposure in occupational populations may lead to a decline in pulmonary ventilatory function and alterations in peripheral blood inflammatory indicators. Inflammatory indicators may be involved in the pulmonary function decline caused by chromate exposure.

Objective:By systematically evaluate the implementation of GBZ 2.1, so as to provide technical basis for the future revisions of this standard.Methods:From May to October 2023, Based on the pre survey questionnaire, the semi-structured interview method was used to interviews with experts from CDC, Occupational disease prevention and control hospital institutes, employers, occupational hygiene technical service intermediaries and universities, and the inductive method was used to extract the topics and relevant suggestions.Results:Generally, GBZ 2.1 is scientific, practical, progressiveness and operable. There are still some issues such as OELs overlapping and the correspondence between Chinese and English names. The outstanding problem is the coordination with other standard contents.Conclusion:The technical indicators in GBZ 2.1 could adapt to the needs of current practical work. The coordination between standards needs to be clarified, and the new recommended content needs further promotion and exploration on how to implement it.

Objective:To investigate the safety and therapeutic effect of split liver transplantation (SLT) in clinical application.Methods:This is a retrospective case-series study. The clinical data of 203 consecutive SLT, 79 living donor liver transplantation (LDLT) and 1 298 whole liver transplantation (WLT) performed at the Third Affiliated Hospital of Sun Yat-sen University from July 2014 to July 2023 were retrospectively analyzed. Two hundred and three SLT liver grafts were obtained from 109 donors. One hundred and twenty-seven grafts were generated by in vitro splitting and 76 grafts were generated by in vivo splitting. There were 90 adult recipients and 113 pediatric recipients. According to time, SLT patients were divided into two groups: the early SLT group (40 cases, from July 2014 to December 2017) and the mature SLT technology group (163 cases, from January 2018 to July 2023). The survival of each group was analyzed and the main factors affecting the survival rate of SLT were analyzed. The Kaplan-Meier method and Log-rank test were used for survival analysis.Results:The cumulative survival rates at 1-, 3-, and 5-year were 74.58%, 71.47%, and 71.47% in the early SLT group, and 88.03%, 87.23%, and 87.23% in the mature SLT group, respectively. Survival rates in the mature SLT group were significantly higher than those in the early SLT group ( χ2=5.560, P=0.018). The cumulative survival rates at 1-, 3- and 5-year were 93.41%, 93.41%, 89.95% in the LDLT group and 87.38%, 81.98%, 77.04% in the WLT group, respectively. There was no significant difference among the mature SLT group, the LDLT group and the WLT group ( χ2=4.016, P=0.134). Abdominal hemorrhage, infection, primary liver graft nonfunction,and portal vein thrombosis were the main causes of early postoperative death. Conclusion:SLT can achieve results comparable to those of WLT and LDLT in mature technology liver transplant centers, but it needs to go through a certain time learning curve.

Objective:To investigate the safety and therapeutic effect of split liver transplantation (SLT) in clinical application.Methods:This is a retrospective case-series study. The clinical data of 203 consecutive SLT, 79 living donor liver transplantation (LDLT) and 1 298 whole liver transplantation (WLT) performed at the Third Affiliated Hospital of Sun Yat-sen University from July 2014 to July 2023 were retrospectively analyzed. Two hundred and three SLT liver grafts were obtained from 109 donors. One hundred and twenty-seven grafts were generated by in vitro splitting and 76 grafts were generated by in vivo splitting. There were 90 adult recipients and 113 pediatric recipients. According to time, SLT patients were divided into two groups: the early SLT group (40 cases, from July 2014 to December 2017) and the mature SLT technology group (163 cases, from January 2018 to July 2023). The survival of each group was analyzed and the main factors affecting the survival rate of SLT were analyzed. The Kaplan-Meier method and Log-rank test were used for survival analysis.Results:The cumulative survival rates at 1-, 3-, and 5-year were 74.58%, 71.47%, and 71.47% in the early SLT group, and 88.03%, 87.23%, and 87.23% in the mature SLT group, respectively. Survival rates in the mature SLT group were significantly higher than those in the early SLT group ( χ2=5.560, P=0.018). The cumulative survival rates at 1-, 3- and 5-year were 93.41%, 93.41%, 89.95% in the LDLT group and 87.38%, 81.98%, 77.04% in the WLT group, respectively. There was no significant difference among the mature SLT group, the LDLT group and the WLT group ( χ2=4.016, P=0.134). Abdominal hemorrhage, infection, primary liver graft nonfunction,and portal vein thrombosis were the main causes of early postoperative death. Conclusion:SLT can achieve results comparable to those of WLT and LDLT in mature technology liver transplant centers, but it needs to go through a certain time learning curve.

Objective:To propose a markless patient setup workflow based on the optical surface monitoring system (AlignRT) and open-face mask immobilization for whole-course head tumor radiotherapy, assess the setup time and repositioning frequency of the proposed workflow, and conduct a comparative analysis of the differences, correlation, and consistency of the setup errors of the AlignRT and cone beam CT (CBCT) systems.Methods:A retrospective analysis was conducted for the data on the errors of 132 fractionated setup based on open-face mask immobilization of 33 head tumor patients. AlignRT-guided markless patient setup workflow was applied throughout the radiotherapy. Meanwhile, the body structures automatically generated by the treatment planning system were used as body references. The 6-degree-of-freedom (6DoF) setup errors (lateral, vertical, longitudinal, rotation, pitch, roll, and yaw directions), setup time, and repositioning frequency of the AlignRT and CBCT systems were recorded and analyzed. The Wilcoxon and Spearman analyses were used to statistically assess the differences and correlation of the setup errors of the two systems. Moreover, the Bland-Altman analysis was employed to evaluate the consistency of the two systems.Results:The 6DoF setup errors of CBCT were within the clinical tolerance (linear motions: -0.30 to 0.30 cm; rotational motions: -2.0° to 2.0°). The setup time and repositioning frequency of CBCT were (98 ± 31) s and 1.51% (2/132), respectively. There was no significant difference in setup errors between the two systems except those in x-axis ( Z = -3.11, P= 0.002), y-axis ( Z = -7.40, P<0.001), and Pitch ( Z= -4.48, P<0.001). There was a significant positive correlation between the setup errors along lateral ( rs = 0.47, P<0.001) and vertical ( rs = 0.29, P = 0.001) directions, rotation (Rtn; rs = 0.47, P<0.001), pitch (Pitch; rs = 0.28, P = 0.001) and roll (Roll; rs = 0.45, P<0.001) of the two systems. The 95% limits of agreement (95% LoA) of 6DoF setup errors were -0.12 to 0.09 cm, -0.07 to 0.17 cm, -0.19 to 0.20 cm, -1.0° to 0.9 °, -1.0° to 1.5°, and -0.9° to 1.0°, respectively. The 95% confidence interval (95% CI) of 95% LoA was -0.14 to 0.11 cm, -0.09 to 0.19 cm, -0.23 to 0.23 cm, -1.2° to 1.1°, -1.2° to 1.7°, and-1.0° to 1.1°, respectively, all of which were within the permissible error ranges. The 6DoF setup error difference of 3.41% (27/792< 5%) was beyond the 95% LoA. The maximum absolute differences of 6DoF setup errors within the 95% LoA were 0.12, 0.16, 0.19 cm, 0.9°, 1.5°, and 1.0°, respectively. Conclusions:The proposed markless setup workflow based on AlignRT combined with open-face mask immobilization for whole-course head tumor radiotherapy exhibits reasonable agreement and consistency with the patient setup using CBCT, with acceptable clinical efficiency. It can be applied to the first radiotherapy and the real-time monitoring of therapy to improve the safety and thus is of value in clinical applications.

Objective:To assess the three-dimensional dose distribution in radiotherapy plans using the structural similarity index(SSIM), compare the performance of SSIM with commonly used quality assessment indices, and develop a SSIM-based quality assessment method of multiple prescribed doses.Methods:The SSIM was introduced to providea quality score of various voxels by comparing actual and ideal three-dimensional dose data and combining the spatial location information of the voxels. Then the average value in a region of interest (ROI) was calculated as the quality score of the region. Fifty-three cases of cervical cancer were selected to analyze the correlation of the SSIM with the uniformity index (HI), conformity index (CI) of the dose distribution in various ROIs and to explore the capability of the SSIM to reflect the uniformity and conformity of dose distribution.Two types of quality defects were individually introduced into two of 53 radiotherapy plans. Then the two plans were compared with normal plans to characterize the response of the SSIM.Results:There was no correlation between HI and SSIM in positive lymph nodes(PGTVnd) due to the decrease in the HI sensitivity, while there was a significant negative correlation between them in regions where PGTVnd was removed from the planning target volume(PTV, R=-0.86, P<0.01). Meanwhile, there was a significant positive correlation between CI and SSIM in PGTVnd ( R=0.83, P<0.01). Therefore, the SSIM can be used to identify the artificial design defects in plans by determining abnormal dose gradients. Conclusions:Apart from reducing the defects of previous assessment parameters, the SSIM has the capability to assess the quality of radiotherapy plans by combining the uniformity and conformity of dose distribution and can provide accurate feedback on the spatial locations of quality defects.

Objective To evaluate the effect of microvascular invasion (MVI) on prognosis of recipients after liver transplantation for primary liver cancer (liver cancer). Methods Clinical data of 177 recipients after liver transplantation for liver cancer were retrospectively analyzed. All patients were divided into the MVI-positive group (n=64) and MVI-negative group (n=113) according to postoperative pathological examination results. Clinical data were statistically compared of all recipients between the negative and positive MVI groups. The prognosis and risk factors of liver transplantation recipients for liver cancer were analyzed. Results Among 177 recipients, 64 cases (36.2%) were positive for MVI and 113 (63.8%) negative for MVI. Compared with the MVI-negative recipients, MVI-positive recipients had significantly lower degree of tumor differentiation, higher preoperative alpha-fetaprotein (AFP) level, larger maximal tumor diameter, a larger quantity of tumors, more satellite lesions and more recipients who did not meet the Milan criteria (all P < 0.05). The 1-, 3- and 5-year overall survival (OS) and recurrence-free survival (RFS) of recipients after liver transplantation for liver cancer were 80.2%, 62.1%, 58.5% and 66.3%, 57.5%, 51.2%, respectively. The 1-, 3- and 5-year OS and RFS of MVI-positive recipients were 70%, 39%, 35% and 53%, 39%, 33%, significantly lower than 86%, 75%, 72% and 73%, 68%, 63% of their counterparts negative for MVI (all P < 0.05). Cox regression analysis showed that the maximal tumor diameter >8 cm, preoperative AFP level ≥20 ng/mL, low degree of tumor differentiation and positive MVI were the independent risk factors for OS of recipients after liver transplantation for liver cancer (all P < 0.05). Positive MVI, low degree of tumor differentiation and preoperative down-staging failure were the independent risk factors for RFS of recipients after liver transplantation for liver cancer (all P < 0.05). Conclusions MVI is of significant clinical value in predicting clinical prognosis of recipients after liver transplantation for liver cancer.