Objective To evaluate the influence of the wearing position of dosimeters outside lead aprons on effective dose estimation for interventional radiology workers, analyze the differences between single and double dosimeter methods in effective dose estimation, and provide a reference for the personal dose monitoring of interventional radiology workers. Methods This study employed a combined approach of on-site monitoring and Monte Carlo simulation to evaluate the impact of the wearing position of dosimeters outside lead aprons on effective dose estimation, as well as the differences between effective doses measured using single and double dosimeters. Interventional radiology workers wore dosimeters at three positions: the neck outside the lead collar, the left chest outside the lead apron, and inside the lead apron. Effective doses were estimated using the single and double dosimeter methods specified in GBZ 128-2019 Specifications for individual monitoring of occupational external exposure, and the impact of different wearing positions on the estimation results was compared. Geant4 Monte Carlo simulations were used to model dose distributions at the neck outside the lead collar and at the left chest outside the lead apron for operators performing cardiovascular interventions under tube voltages of 70, 80, 90, and 100 kVp and exposure angles of posteroanterior (PA), anteroposterior (AP), and left anterior oblique 45° (LAO45°) positions. The study assessed the impact of dosimeter wearing position on effective dose estimation. Results Monte Carlo simulations demonstrated that neck doses consistently exceeded left chest doses across different tube voltages and exposure angles, with neck-to-chest dose ratios of 0.80-0.90. Under identical tube voltage conditions, AP showed the highest doses, followed by LAO45°, and PA demonstrated the lowest doses. The single and double dosimeter methods exhibited consistent patterns in effective dose estimation. Single dosimeter method generally yielded higher effective doses with relative deviations of 9.9% to 83%, though these deviations decreased under high tube voltages. Field monitoring data indicated that most interventional radiology workers maintained relative deviations between single and double dosimeter calculations below 6%, with neck-to-chest dose ratios of 0.95-1.1. The estimation patterns remained consistent across both methods, though single dosimeter method showed slightly higher results. Conclusion Under PA, AP, or LAO45°, the doses at the neck consistently exceeded those at the left chest. Therefore, when wearing lead protective equipment, the dosimeter should be properly positioned at the neck outside the lead collar to accurately reflect the radiation doses of surgeons. Some interventional radiology workers improperly positioned the dosimeter (intended at the neck outside the lead collar) at the left chest outside the lead apron, and this may result in an underestimation of the effective dose.

Objective To discuss the influence of coronary computed tomography angiography(CCTA)on correctness of assessing revascularization in patients with coronary artery disease. Methods A retrospective study method was conducted,605 cases underwent CCTA before coronary angiography(CAG)from 2008 to 2009 in Chinese PLA General Hospital were selected as CCTA before CAG group,and meanwhile 616 cases examined by CAG directly were selected as direct CAG group. Patients with multiple procedures of CAG were excluded. The proportions of various treatment strategies were compared,including per-cutaneous coronary intervention(PCI),coronary artery bypass grafting(CABG),medical therapy(MT),normal rate of CAG and the correctness of assessing revascularization between the two groups. Results The comparison between the baseline of the two groups showed that in the CCTA before CAG group,there were more severe lesions than those in the direct CAG group,such as Syntax score(11.31±8.90 vs. 10.23±9.73,P<0.05). Compared with direct CAG group,the triage of PCI and CABG in the CCTA before CAG group was significantly increased〔PCI:65.3%(395/605)vs. 57.1%(352/616),CABG:16.5%(100/605)vs. 3.4%(21/616)〕,while the percentages of medical treatment and normal CAG were obviously reduced〔medical treatment:11.7%(71/605)vs. 19.3%(119/616),normal rate of CAG:6.4%(39/605)vs. 20.1%(124/616),all P<0.01〕. With the guidance of CCTA,the correctness of assessing revascularization was increased〔81.8%(495/605)vs. 60.6%(373/616),P<0.01〕. Conclusion Compared with the direct induction by CAG,the CCTA examination carried out before CAG is capable of increasing the rate of correctness in the determination of revascularization in coronary heart diseases.

Objective To improve the diagnosis and treatment of pulmonary lymphangiomyomatosis (PLAM). Methods The clinical data of 1 PLAM case in our hospital was analysed, along with a review of the related literatures.Results PLAM was a rare diffuse interstitial plumonary disease of unknown cause, which was oiraracterized by recurrent spontaneous pneumothorax shortness of breath (dyspnea) with physical activity, haemopthsis and chylothorax. Radiological appearances were extensive bilateral linear pattern, and honeycomb pattern in the end. High resolution CT scan (HRCT) showed multiple thin walled cysts distributed evenly throughout the bilateral lung fields with normal intervening lung parenchyma. Pathological characters were abnormal, pervasice multiplication of smooth muscle of cell in and around the small airway, lymphatic and small blood vessels. Immunohistochemical test showed HMB45(+).Conclusion It should be considered the probability of PLAM when women of childbearing ages have some clinical manifestations as follows, the increasing dyspnoea that can not be relieved similar to emphysema, high- resolution CT scan (HRCT) shows multiple thin walled cysts distributed evenly throughout the bilateral lung fields with normal intervening lung parenchyma, and recurrent pneumothorax or chylothorax. The optimal confirm diagnostic method is lung tissue biopsy.