Objective To compare the response capability of active personal dosimeters (APDs) in the pulse radiation field of interventional radiology, and to find APDs that can be used for dose optimization monitoring for interventional radiology staff. Methods Seven models of APDs and dose monitoring systems were tested in the following four types of radiation fields: continuous radiation field (Cs-137), single-pulse radiation field (80 kV, 10 mA, 10～1000 ms), multi-pulse standard radiation field (70 kV, 20～500 mA, 1～20 ms/pulse, frames per second 1～20), and multi-pulse scattering field (angiography machine, irradiation field: 15 cm × 15 cm, 22 cm × 22 cm, 27 cm × 27 cm, angiography: 65～74 kV, 6.2～8.2 mA; photography: 65 kV, 343～479 mA). Results All APDs showed good dose responses in the continuous radiation field. The ratio of the results obtained with and without phantom was 1～1.1. In the single-pulse radiation field, DMC3000 and TruDose showed good dose response, linearity, and repeatability. Under the main ray of the multi-pulse radiation field, DMC3000 and TruDose showed good dose response, linearity, and repeatability as the dose rate increased, and there were 5%～13% differences in the response ability between the two models. In angiography machine scattering field, the ratios of the results obtained from DMC3000, TruDose, and RaySafei3 to those from thermoluminescence dosimeter were 1.08 ± 0.09, 0.95 ± 0.11, and 1.13 ± 0.11, respectively. Conclusion DMC3000, TruDose, and RaySafei3 can be used in clinics as auxiliary dosimeters to optimize radiation dose monitoring and radiation protection measures for people at high risk of occupational diseases. Interventional radiology workers can implement actions to reduce the cumulative dose based on real-time dose information, thereby reducing the radiation dose.

Objective To measure the air-absorbed dose rate of gamma radiation in public areas for the situation of the local radiation environment. Methods Using a large-volume γ spectrometer system with a NaI(Tl) detector mounted on a UAV, we conducted large-scale airborne radiation monitoring in public areas in southwestern China, to measure the air-absorbed dose rate at a height of 1 m from the earth’s surface. Results The airborne radiation monitoring data were used to analyze the local radiation environment. The mean air-absorbed dose rate at a height of 1 m was 43.6 ± 12.9 nGy/h. Seven abnormal radiation points were detected, and two of them were located where construction was ongoing. At one of the abnormal radiation points, FH40G meter measurements showed that the air-absorbed dose rate at a height of 1 m was up to 22.0 μGy/h. Field soil samples were collected for HPGe γ spectrometer analysis: the ²³²Th radionuclide activity concentration was 96.0 kBq/kg, and the ²²⁶Ra radionuclide activity concentration was 9.9 kBq/kg. Conclusion Using the UAV-mounted large-volume γ spectrometer system with NaI(Tl) detectors for large-scale airborne monitoring is a fast and effective method for dragnet monitoring of the level of radiation in public areas.

Objective To track and evaluate the scientificity, applicability, and operability of the current implementation of the Radiation Shielding Specifications for Radiotherapy Treatment Rooms—Part 2: Radiotherapy Room of Electron Linear Accelerators (GBZ/T 201.2—2011) among personnel in medical radiation technology service institutions, and to provide scientific evidence for further improvement of the standard. Methods Following the Guidelines for Health Standards Tracking Evaluation Work (WS/T 536—2017) and the project implementation plan, a survey was conducted among 140 personnel engaged in shielding testing and evaluation of electron linear accelerator rooms in medical radiation technology service institutions from 24 provinces in China. The methods of pre-investigation, on-site research, mailing, and email were used to collect data for analysis. Results Questionnaires were completed by 140 respondents from 98 medical radiation service institutions, including 63 public institutions and 77 private institutions. Of the surveyed individuals, 86.68% claimed to have a good or very good understanding of the standard, while only 64.3% had participated in training related to the standard. The survey indicated a low level of mastery of the standard content among the personnel and insufficient efforts in training and dissemination. Although only 3.57% of the respondents considered the existing standard to be inapplicable in the context of new radiotherapy equipment and technological advancements, 95.71%, 93.57%, and 96.43% believed that shielding calculation examples should be added for tomotherapy devices, CyberKnife systems, and ring accelerators with self-shielding bodies. Furthermore, 65% of the respondents felt that neutron shielding should be considered for 10 MV X-ray accelerator rooms. Conclusion The GBZ/T 201.2—2011 has been widely used for radiation protection in radiotherapy. However, it is imperative to update this standard. Additionally, due to the technical complexity of the standard, it can be challenging for professionals to fully understand and implement it. Therefore, publicity goals should be tailored to different groups and the training of key personnel should be strengthened. A nationwide communication and cooperation mechanism should be established to ensure uniform implementation of the standard.

Objective To track and evaluate the implementation of the Radiation Shielding Requirements in Room of Radiotherapy Installations—Part 1: General Principle (GBZ/T 201.1–2007) among relevant personnel in medical radiation institutions, and to provide a scientific basis for revising the standard. Methods According to the Guidelines for Health Standards Tracking Evaluation (WS/T 536–2017) and the implementation protocol of standard evaluation, an online survey was conducted among 212 relevant workers from 146 medical radiation institutions across 18 provinces in China. The data were aggregated and analyzed with the use of Microsoft Excel 2010. Results A total of 215 questionnaires were returned, of which 212 were valid. Among the valid respondents, 77.8% believe that this standard is universally applied; 96.2% believe that this standard can meet work needs; 63.7% have participated in relevant training on this standard; 74.1% use this standard once or more per year; and 10.8% believe that this standard needs to be revised. Conclusion Medial radiation workers have a high rate of awareness of the basic information and content of the standard, but the understanding and application of the standard content need to be improved. We recommend that relevant departments further strengthen the promotion of and training on the standard, revise some content based on actual situation, and improve workers’ ability to use the standard.

Objective To develop a large-volume sample cassette in the shape of a formalin cup suitable for portable HPGe γ spectrometer, to determine the detection limits of the cassette at different detection times through fresh sample measurements, and to provide a reference for responding to and monitoring of nuclear and radiation emergencies. Methods According to the formula for calculation of detection limit described in the GB/T 16145—2022, ¹³¹I and ¹³⁷Cs were measured using the sourceless efficiency calibration software Angle and the portable HPGe γ spectrometer for the optimization of the large-volume sample cassette. Fresh salmon samples were measured using a formalin cup-shaped large-volume sample cassette. The detection times were 2, 4, 6, 8, 10, 19, 19, 22, and 24 hours. The relationship between detection time and detection limit was assessed. Results Using sample cassettes with 15 cm radius and 10 L volume, the simulated detection efficiency of the formalin cup-shaped large-volume sample cassette was 30%-46% higher and the detection limit was lower as compared with the cake-shaped large-volume sample cassette. The detection limit obtained by measuring fresh salmon samples decreased with the extension of the detection time. These results provided a reference for the detection limits of measuring fresh samples for nuclides of concern in nuclear contaminated water with different detection times. Conclusion The formalin cup-shaped large-volume sample cassette developed by combining the optimization of detection limit provides a geometry for quantitative analysis in on-site monitoring of γ nuclides in the case of emergencies. Measurement of fresh samples using the cassette with different detection times showed that 8-10 hours of detection was optimal in balancing the detection limit and the detection time.

Objective To investigate the exposure level of radioactive hazard factors and the health management of radiation workers in non-medical radiation institutions (excluding military institutions) in Jinan, China through radioactive hazard factor monitoring, to identify the weak links, and to provide a scientific basis for future work priorities. Methods According to the monitoring plan formulated by Jinan Municipal Health Commission, the task undertaking institutions at all levels in Jinan investigated the types of radioactive hazard factors, detection, training, and health monitoring of 101 non-medical radiation institutions in Jinan. In addition, the workplace radiation levels were detected in 25 institutions of 6 types of monitoring objects, including industrial flaw detection, non-medical accelerator, non-sealed radioactive material workplace, nuclear instrument, baggage detector, and others. Results The investigation objects included institutions engaged in industrial flaw detection, nuclear instrument, luggage detector, non-medical accelerator, non-sealed source workplace, and others. Of these institutions, 91.84% were equipped with radiation protection detectors, 92.86% were equipped with personal dose alarm, 97.73% were equipped with personal protective equipment, 94.36% performed radiation protection training, 92.69% employed radiation workers with certificates, 95.77% performed personal dose detection, 94.83% performed occupational health examination, and 100.00% were qualified for radiation protection detection in workplace. Conclusion There is still a gap between the radiation protection status of non-medical institutions in Jinan and the national regulations and standards, so it is necessary to further strengthen supervision and law enforcement and make greater efforts in training and publicity.

kV X-ray radiotherapy was the primary mode of radiotherapy widely used to treat many types of cancer, including deep tumors, before the invention of the Co-60 therapy machine and the electron linear accelerator, which gradually replaced kV X-ray radiotherapy. kV X-ray radiotherapy equipment requires less space and shielding, and still has application value in the treatment of skin lesions and superficial tumors. Especially in recent years, kV X-ray has been used in the treatment of keloid, and electronic brachytherapy equipment has been used in intracavitary, intraoperative, and superficial radiotherapy. Therefore, kV X-ray radiotherapy has seen renewed application. The quality control of kV X-ray radiotherapy equipment is the key to ensure the treatment effect and safety of patients. This paper reviews the current status of quality control of kV X-ray radiotherapy equipment and provides a reference for the formulation of quality control assessment standards for kV X-ray radiotherapy equipment.

Objective To provide data base for the development of X-ray computed tomography (CT) diagnostic reference levels suitable for the physical characteristics of residents in Qingdao City, China. Methods A total of 3351 cases of adult CT scan data derived from 14 devices were randomly selected from three tertiary hospitals and one primary hospital from January 1 to December 31, 2022. CT examination was performed on the brain, paranasal sinus, neck, chest, abdomen, cervical vertebrae, and lumbar vertebrae. The cases also included CT angiography (CTA) data on the brain, neck artery, pulmonary artery, and aorta. The data types included tube voltage (kV), effective tube current (mAs), computed tomography dose index volume (CTDI_vol), and dose length product (DLP). The 1st, 2nd, 3rd quartile values of CTDI_vol and DLP were calculated. Results Large differences were observed in DLP among different body parts of adults. The DLP value showed a descending order of craniocerebral CTA, craniocerebral CT, abdomen CT, lumbar vertebral spiral CT, aorta CTA, pulmonary artery CTA, paranasal sinus CT, chest CT, cervical vertebral spiral CT, and neck CT. The 3rd quartile DLP values of the brain and neck were 657.9 and 228.1 mGy·cm, respectively. The CTDI_vol of the brain was largest (3rd quartile, 52.0 mGy) and the CTDI_vol of the chest was smallest (3rd quartile, 8.2 mGy). Conclusion There are significant differences in CTDI_vol and DLP between different body parts of adults in Qingdao City, and CT radiation dose levels are relatively low compared to other regions in China and other countries.

Objective To investigate the role of hydrogen therapy in reducing radiation-induced lung injury and the specific mechanism. Methods Forty C57BL/6 mice were randomly divided into four groups: normal control group, model group, hydrogen therapy group I, and hydrogen therapy group II. A mouse model of radiation-induced lung injury was established. The pathological changes in the lung tissue of the mice were examined with HE staining. Immunofluorescence staining was used to detect the expression of surface markers of M1 and M2 macrophages to observe macrophage polarization. The expression of interleukin (IL)-6, tumor necrosis factor-α (TNF-α), and IL-10 in the lung tissue was measured by immunohistochemistry. The expression of nuclear factor-kappa B (NF-κB) p65 and phosphorylated NF-κB (P-NF-κB) p65 was measured by Western blot. Results HE staining showed that compared with the control group, the model group exhibited alveolar septal swelling and thickening, vascular dilatation and congestion, and inflammatory cell infiltration in the lung tissue; the hydrogen groups had significantly reduced pathological damage and inflammatory response than the model group, with more improvements in hydrogen group II than in hydrogen group I. Immunohistochemical results showed that compared with those in the control group, the levels of the inflammatory cytokines IL-6 and TNF-α were significantly increased in the model group; the hydrogen groups showed significantly decreased IL-6 and TNF-α levels and a significantly increased level of the anti-inflammatory factor IL-10 than the model group, which were more marked in hydrogen group II than in hydrogen group I. Immunofluorescence results showed that compared with the control group, the expression of the surface marker of M1 macrophages in the model group was significantly upregulated; the hydrogen groups showed significantly downregulated M1 marker and significantly upregulated M2 marker, and hydrogen group II showed significantly increased M2 marker compared with hydrogen group I. Western blot results showed that compared with that in the control group, the ratio of P-NF-κB p65/NF-κB p65 in the model group was significantly increased; the P-NF-κB p65/NF-κB p65 ratio was significantly reduced in the hydrogen groups than in the model group, and was significantly lower in hydrogen group II than in hydrogen group I. Conclusion Hydrogen inhalation therapy may reduce the inflammatory response of radiation-induced lung injury by inhibiting the NF-κB signaling pathway to promote the polarization of the macrophage M1 subtype to the M2 subtype.

Objective To analyze the magnetic resonance images (MRI) of patients with spinal epidural lipomatosis (SEL) in high-altitude areas and to determine the optimal cut-off value for diagnosis with epidural fat thickness. Methods This retrospective study included patients who underwent lumbosacral MRI examination for lumbosacral pain in Ping’an District Hospital of Traditional Chinese Medicine, Haidong City, China from January 1, 2021 to December 31, 2022. The epidural fat thickness in vertebral segments T12/L1 to L5/S1 was compared between the SEL group and the non-SEL group. The diagnostic efficacy with different cut-off values at each vertebral segment was evaluated. Between-group comparisons were performed using the t-test, Mann-Whitney U test, chi-square test, or modified chi-square test. The area under the receiver operating characteristic (AUC) was used to evaluate the diagnostic efficiency. The DeLong test was used to compare AUC between the two groups. Results A total of 370 patients were included (60 in the SEL group and 310 in the non-SEL group). There were no significant differences in age, sex, height, body weight, and body mass index between the two groups (all P > 0.05). At different vertebral segments, the epidural fat thickness was significantly higher in the SEL group than in the non-SEL group (all P < 0.05). The cut-off values for SEL diagnosis with epidural fat thickness in segments T12/L1 to L5/S1 were 2.23, 4.25, 4.85, 5.57, 7.21, and 8 mm, respectively. The AUC of MRI SEL diagnosis with epidural fat thickness in segment L5/S1 was the highest (0.945, 95% confidence interval [CI]: 0.916-0.966, P < 0.001). SEL diagnosis with epidural fat thickness > 8 mm in segment L5/S1 was the most accurate, with an AUC of 0.931 (95% CI: 0.901-0.955, P < 0.001), a sensitivity of 95.0%, and a specificity of 91.3%; this AUC was significantly higher than those of diagnosis with other cut-off values (all P < 0.05). Conclusion SEL patients have significantly increased epidural fat in the spinal canal. Epidural fat thickness > 8 mm in segment L5/S1 can be used for diagnosis of SEL with improved efficiency and accuracy.

Objective To evaluate the application of three deep learning algorithms in automatic segmentation of clinical target volumes (CTVs) in high-dose-rate brachytherapy after surgery for endometrial carcinoma. Methods A dataset comprising computed tomography scans from 306 post-surgery patients with endometrial carcinoma was divided into three subsets: 246 cases for training, 30 cases for validation, and 30 cases for testing. Three deep convolutional neural network models, 3D U-Net, 3D Res U-Net, and V-Net, were compared for CTV segmentation. Several commonly used quantitative metrics were employed, i.e., Dice similarity coefficient, Hausdorff distance, 95th percentile of Hausdorff distance, and Intersection over Union. Results During the testing phase, CTV segmentation with 3D U-Net, 3D Res U-Net, and V-Net showed a mean Dice similarity coefficient of 0.90 ± 0.07, 0.95 ± 0.06, and 0.95 ± 0.06, a mean Hausdorff distance of 2.51 ± 1.70, 0.96 ± 1.01, and 0.98 ± 0.95 mm, a mean 95th percentile of Hausdorff distance of 1.33 ± 1.02, 0.65 ± 0.91, and 0.40 ± 0.72 mm, and a mean Intersection over Union of 0.85 ± 0.11, 0.91 ± 0.09, and 0.92 ± 0.09, respectively. Segmentation based on V-Net was similarly to that performed by experienced radiation oncologists. The CTV segmentation time was < 3.2 s, which could save the work time of clinicians. Conclusion V-Net is better than other models in CTV segmentation as indicated by quantitative metrics and clinician assessment. Additionally, the method is highly consistent with the ground truth, reducing inter-doctor variability and treatment time.

Objective To understand the levels and trends of personal doses of occupational external exposure among radiation workers in medical institutions in Huizhou City and to improve radiation protection management. Methods Thermoluminescent dosimetry was employed to monitor the personal doses of occupational external exposure of radiation workers over monitoring cycles spanning three months each. Results From 2019 to 2023, a total of 25 796 monitoring instances were recorded for radiation workers in medical institutions in Huizhou City. Diagnostic radiology workers accounted for the largest proportion of workforce in the occupational categories, followed by interventional radiology workers. The average annual effective dose per person ranged from 0.21 to 0.30 mSv, with an average of 0.26 mSv. The majority of annual effective dose per person was below 1.0 mSv, with no instances exceeding 20 mSv. Among all occupational categories, nuclear medicine workers had the highest average annual effective dose per person at 0.43 mSv, followed by interventional radiology workers at 0.37 mSv. There was a significant difference in the average annual effective dose per person among different occupational categories (P < 0.05), with nuclear medicine and interventional radiology workers having higher doses than workers in diagnostic radiology, dental radiology, and other applications (all P < 0.05). Conclusion The personal dose monitoring results for radiation workers in medical institutions in Huizhou City are at low levels, indicating that the radiation protection in the local medical institutions is sufficient and can effectively protect the occupational health of radiation workers.

Objective To investigate the clinical characteristics and dosimetric parameters associated with acute hematologic toxicity (AHT) resulting from radiation-induced damage to hematopoietic organs in patients undergoing chemoradiotherapy for cervical cancer and to provide a reference for establishing dose constraints in relevant regions of interest (ROIs) and predicting adverse tissue reactions during the development of clinical treatment plans. Methods A retrospective analysis was conducted on 556 patients with cervical cancer who underwent chemoradiotherapy at our hospital. Univariate (χ² and t-test) and multivariate (binary logistic regression analyses) methods were employed to investigate the association of clinical factors and pelvic dose-volume parameters with grade ≥ 3 AHT in patients with cervical cancer. Clinical factors comprised patients’ age, clinical stage, pathologic stage, whether the patient had received chemotherapy in the radiotherapy cycle of interest, and dose-volume dosimetric parameters V_x and D_mean for pelvic bone marrow (BM) and femoral head (FH) structures. Results The incidence of AHT among the included cases was 30.4% (169/556). Chi-square analysis of the clinical factors revealed that whether the patient had received chemotherapy, patient’s age, and pathologic stage had a significant impact on AHT. Univariate analysis showed that the factors associated with AHT were mean dose, V₅, V₁₀, V₁₅, V₂₀, and V₂₅ of BM and FH; dosimetric parameters such as V₃₅ of FH had a significant impact on the development of AHT. Multivariate logistic regression analysis identified V₁₅ of pelvic BM as an independent risk factor for AHT (P=0.041), with a threshold value of 84.29% as determined by a receiver operating characteristic (ROC) curve. Conclusion Whether a patient had received chemotherapy in the radiotherapy cycle of interest, and patient’s age and pathologic stage can serve as predictors of AHT. V₁₅ of BM is an independent risk factor for AHT development. Therefore, when formulating a treatment plan, it is crucial to ensure that pelvic V₁₅ remains below 84.29% to effectively reduce the incidence of grade ≥ 3 acute bone marrow depression.

Objective To establish a method to characterize the size and density of the female breast based on three-dimensional images of breast cone-beam computed tomography (CBCT), and describe the breast characteristics of women in a region of China, and to explore its value in dosimetric assessment for breast CBCT examinees. Methods We retrospectively surveyed the breast CBCT images of 203 women in a grade A tertiary hospital in a southwestern city of China from January 2021 to March 2023. The effective diameter of the breast at the chest-wall (D_eff), chest wall-to-nipple length (CNL), the effective diameter of the breast at half of CNL (D_h/2), breast volume (BV), glandular volume (GV), and volumetric breast density (VBD) were measured using the specific tools of the Koning Imaging Viewer system. The differences between groups were assessed using the Kruskal-Wallis H test. The correlation between variables was assessed using the Spearman’s correlation coefficient. Results The median values of D_eff, D_h/2, CNL, BV, GV, and VBD of the surveyed population were 11.9 cm, 8.3 cm, 6.5 cm, 327.7 cm³, 47.0 cm³, and 15.4%, respectively. GV and VBD had significant negative correlations with age. D_eff, D_h/2, CNL, and BV were significantly negatively correlated with VBD. Conclusion We established a quantitative method to analyze female breast characteristics based on three-dimensional breast CBCT images, and preliminarily characterized the female breast in a region of China, which can provide methodological support for the investigation of female breast characteristics in various regions of China in the future.

Objective To clarify the effects of 5G mobile phone radiofrequency radiation exposure on male mouse fertility and to preliminarily explore the underlying mechanisms. Methods Healthy male C57BL/6 mice aged 7-8 weeks were randomly assigned to Sham group, 3.5 GHz radiofrequency radiation group, and 4.9 GHz radiofrequency radiation group, with 16 mice in each group. The mice were exposed to 3.5 GHz or 4.9 GHz mobile phone radiofrequency radiation for 42 consecutive days (1 h per day). The sperm quality was evaluated using sperm count, deformity rate, and motility. H&E staining was performed to assess testicular tissue structure by observing the morphology of spermatogenic cells at various development stages, the diameter of seminiferous tubules, and the thickness of seminiferous epithelium. The sperm mitochondrial function was assessed using sperm mitochondrial membrane potential and testicular ATP content. The fertility of mice was evaluated through fertility rate, litter size, and survival rate of offspring. The underlying mechanisms were explored by detecting the methylation of LRGUK gene and its mRNA and protein levels. Results Compared with the Sham group, there were no significant changes in sperm count in the 3.5 GHz and 4.9 GHz groups; however, the sperm abnormality rate significantly increased (P < 0.05) and sperm motility significantly decreased (P < 0.05). The structure of testicular tissue, the function of sperm mitochondria, and fertility of mice showed no significant changes as compared with the Sham group. The methylation level of LRGUK gene in the testes significantly increased, while the mRNA and protein expression levels significantly decreased. Conclusion Exposure to 3.5 GHz and 4.9 GHz mobile phone radiofrequency radiation for 42 consecutive days can lead to an increase in sperm deformity rate and a decrease in sperm motility in mice, but has no significant effect on fertility, which may be related to an increase in methylation level of the LRGUK gene in the testes.

As the clinically most common endocrine system disease, thyroid disorder is a global health problem characterized by high incidence and high disease burden. Currently, surgery remains the standard treatment of most thyroid cancers; however, active surveillance remains a feasible option for treatment of low-risk thyroid disorders. As the currently most widely used approach of thermal ablation, radiofrequency ablation is a safe and effective treatment for a variety of thyroid disorders. The review presents the advances in the efficacy and complications of radiofrequency ablation for treatment of benign thyroid nodules, follicular thyroid adenoma, and primary and recurrent thyroid cancers.

Objective To compare the value of low-dose spiral CT and conventional-dose CT for diagnosis of benign and malignant pulmonary nodules, so as to provide a reference for early screening of lung cancer. Methods A total of 288 patients diagnosed with pulmonary nodules in Ningguo Municipal People’s Hospital during the period from January 2019 to August 2023 were enrolled, and all patients underwent low-dose chest spiral CT and conventional-dose CT scans. The pathological biopsy of pulmonary nodules served as a gold standard. The sensitivity, specificity, and accuracy of low-dose spiral CT and conventional-dose CT for diagnosis of benign and malignant pulmonary nodules and the detection rates of vascular aggregation sign, pleural indentation sign, lobulation sign, and spiculation sign were compared. Results The 288 patients with pulmonary nodules included 186 men and 102 women, with a mean age of 61.12 ± 8.34 years. Among these patients, 218 had benign pulmonary nodules and 70 had malignant pulmonary nodules. There were no significant differences between patients with benign and malignant pulmonary nodules in terms of sex, mean age, and the size, location, and characteristics of pulmonary nodules (all P values > 0.05). However, significant differences were observed in terms of changes in pulmonary nodule size, history of smoking, history of pulmonary infections, and family history of cancers (all P values < 0.05). With pathological biopsy of pulmonary nodules as a gold standard, the sensitivity, specificity, and accuracy of conventional-dose CT and low-dose spiral CT for diagnosis of benign and malignant pulmonary nodules were 94.29% and 92.86%, 93.57% and 92.20%, and 93.75% and 92.36%, respectively, with no significant differences (χ² = 1.975, 1.012, and 1.911, all P values > 0.05). There was no significant difference in the area under the receiver operating characteristic curve between conventional-dose CT and low-dose spiral CT (0.937 vs. 0.921; t = 1.021, P > 0.05). The detection rates of vascular aggregation sign, pleural indentation sign, lobulation sign, and spiculation sign were 20.49% and 19.79%, 23.26% and 22.57%, 37.50% and 35.76%, and 29.17% and 27.43%, respectively, for conventional-dose CT and low-dose spiral CT, with no significant differences (χ² = 0.171, 0.212, 1.012, and 1.110, all P values > 0.05). Conclusion The diagnostic sensitivity, specificity, and accuracy of benign and malignant pulmonary nodules and the detection rate of pulmonary nodule signs are comparable between conventional-dose CT and low-dose spiral CT. However, low-dose spiral CT has lower radiation dose and higher safety, which deserves extensive applications in early screening for lung cancer.

Objective To investigate the correlations of computed tomography (CT), clinical, and pathological features in patients with invasive lung adenocarcinoma positive and negative for spread through air spaces (STAS). Methods A total of 236 patients with invasive lung adenocarcinoma confirmed by surgery and pathology were selected, including 118 patients in STAS-positive group and 118 patients in STAS-negative group. The clinical data, CT signs, and pathological features of the two groups were collected and analyzed. Results There was a correlation between age and the occurrence of STAS. The age of the positive group was higher than that of the negative group. Smoking history and family history of tumor had no correlation with the occurrence of STAS. CT features signs such as nodule type and shape, tumor-lung interface, lobulation sign, spiculation sign, vacuole/cavity, air-bronchogram, pleural indentation sign, vascular changes, mean diameter of tumor, mean diameter of solid component, and the percentage of tumor solid components were significantly different between patients with and without STAS. The incidence of STAS in patients with solid nodules and partial solid nodules was significantly higher than that in patients with ground glass nodules. Multivariate analysis showed that the percentage of tumor solid components, air-bronchogram sign, lobulation sign, and tumor-lung interface were independent risk factors for predicting the occurrence of STAS. Conclusion The clinical data and CT signs of patients with invasive lung adenocarcinoma are related to the occurrence of STAS. CT signs such as the percentage of tumor solid components, air-bronchogram, lobulation sign, and tumor-lung interface are of great significance to STAS prediction. Our findings provide an important basis for selection of personalized clinical treatment plans.

Objective To investigate the clinical application of three-dimensional intracavitary/free-hand interstitial brachytherapy technique in radical radiotherapy for cervical cancer. Methods A retrospective study was conducted on the clinical data of patients with cervical cancer who underwent radical radiotherapy using CT-guided three-dimensional intracavitary/free-hand interstitial brachytherapy technique in The Affiliated Cancer Hospital of Nanjing Medical University from April 2019 to September 2021. The short-term efficacy and adverse reactions were analyzed, and the independent predictors affecting short-term efficacy were evaluated by logistic risk regression model. Results A total of 182 patients were included, and all patients successfully completed the treatment. Clinical efficacy assessment performed 3 months after treatment revealed an overall response rate of 90.65%; the incidence of grade 3 and 4 adverse reactions in the lower gastrointestinal tract was 4.4% during treatment. After reclassifying stage IIIC patients according to the International Federation of Gynecology and Obstetrics (FIGO) 2009 staging system and including factors affecting the stage, it was found that the tumor volume before brachytherapy was the main factor affecting the clinical efficacy of patients at this stage (P = 0.004). Conclusion As a key method in radical radiotherapy for cervical cancer, three-dimensional intracavitary/free-hand interstitial brachytherapy technique is safe and effective and can be quickly popularized in primary hospitals beyond regional cancer centers for cervical cancer brachytherapy.