Objective:To investigate the status and diagnostic reference levels (DRLs) of adult CT radiation dose based on survey result from some hospitals in Beijing.Methods:From September to December 2023, the survey results for 50 hospitals were collected in Beijing, including 47 tertiary hospitals and 3 second grade general hospitals. The CT data sets in total of 20 items including head (sequential scanning), head (spiral scanning), head perfusion, sinus, neck, chest, chest (low dose scanning), abdomen, pelvis, abdomen-pelvis, chest-abdomen-pelvis, lumbar spine, CT urography, coronary CTA (retrospective), coronary CTA (prospective), head CTA, neck CTA, aorta CTA, leg CTA and knee were collected on clinical commonly used CT scanners with annual qualified state inspection. For each item, radiation dose data was collected continuously and randomly for up to 50 cases for every CT scanner. Using the volume CT dose index (CTDI vol) and dose length product (DLP) as dose parameters, the median value of each item in each hospital was obtained. The median CTDI vol and DLP values of all hospitals were arranged, and the local DRL of each item was set as the 75th percentile of the median values. The obtained DRLs were compared with the DRLs issued by domestic and international radiological protection organizations. Results:A total of 26 031 dose values of adult patients were collected and 25 996 dose values were left while 35 invalid values removed.For different CT users, CTDl vol, DLP and scanning phases were different for the same item. The five items with the highest CTDI were head perfusion, head sequential scanning, head spiral scanning, coronary CTA (retrospective mode), and sinus. The five items with the highest DLP were CTU, head perfusion, leg CTA, chest-abdomen-pelvis and aortic CTA. The CTDI vol of CTU was only 16.9 mGy (75th percentile), while the DLP was as high as 2 394.9 mGy·cm (75th percentile). The survey showed that the DRLs of most items in Beijing was lower than the national DRLs of domestic and foreign standards, and the DRLs of a small number of items were slightly higher. Conclusion:The current CT dose level in Beijing is not consistent with national DRLs released at home and abroad, so it is necessary to establish local DRLs according to the clinical status in Beijing.

Objective:To investigate the radiation dose levels of digital radiography (DR) in adult patients and explore the diagnostic reference level (DRL) of radiation dose in Beijing.Methods:Radiation dose data were collected from 39 medical institutions in Beijing on 18 930 DR examinations of chest anterior and lateral view, abdomen anterior and posterior view, abdomen standing view, cervical spine anterior and lateral view, lumbar spine anterior and lateral view, knee joint anterior and lateral view as well as 5 266 digital mammography (CC view and MLO view). For ordinary DR examinations, the incident air kinetic energy ( Ka, i), incident air specific kinetic energy area product ( PKA) and effective dose ( E) to the examined individuals were used for the investigation and estimation of radiation dose. For digital mammography, the average glandular dose (AGD) was calculated. DRLs should be set at the 75 th percentile of median values obtained in each medical institution. Results:The Ka, i, PKA and E of DRL for Chest (PA), Chest (lateral), abdominal(PA), abdominal (AP), Pelvic(AP), Cervical (AP), Cervical (lateral), Lumbar (AP), Lumbar (lateral), Knee joint (AP) and Knee joint (lateral) of conventional DR were 0.14, 0.31, 1.25, 2.18, 1.86, 0.51, 0.14, 2.97, 8.39, 0.37, 0.37 mGy, 159, 259, 1 917, 2 336, 2 867, 312, 301, 3 500, 3 359, 269, 255 mGy·cm 2, 0.03, 0.05, 0.20, 0.43, 0.23, 0.03, 0.02, 0.47, 0.35, <0.001, <0.001 mSv. The DRLs for digital mammography were calculated to be 1.87 mGy (CC view), 1.94 mGy (MLO view) and 3.99 mGy (accumulated for one examination). Conclusions:The radiation dose from DR examinations is relatively low. In clinical practice, the selection of imaging parameters should be further standardized on the basis of the local DRL.

Objective:To investigate devices for radiodiagnosis used in medical institutions in Beijing, China, as well as radiation workers and the devices′ application frequencies, in order to provide data support for determining radiation protection measures and allocating resources for clinical radiodiagnosis.Methods:In October 2023, questionnaires were distributed to the members of the Radiation Technology Branch of the Beijing Medical Association who work in medical institutions at different levels across varying districts of Beijing. The collected data included information about devices for radiodiagnosis and radiation workers, as well as the application frequencies of various medical X-ray imaging devices during 2018-2022, in 38 medical institutions of Level 3 Grade A, Level 3, and Level 2 in 14 municipal districts of Beijing. Then, the collected data were organized using the Microsoft Power BI software to form report models, followed by the statistical analysis of data on the devices, radiation workers, and application frequencies were using the RStudio software.Results:The 38 medical institutions in Beijing possess 591 devices for radiodiagnosis and 2 018 staff in the departments of radiology, including 1 037 radiologic technologists and 738 physicians, with 1.77 technologists and 1.26 physicians arranged for a single device on average. From 2018 to 2022, among all examinations of radiodiagnosis, computed tomography (CT) scans showed the highest frequencies, with total and average annual growth rates of 138.06% and 108.40%, respectively. Specifically, chest CT scans exhibited total and average annual growth rates of 225.20% and 122.50%, respectively. X-ray imaging ranked second in application frequency, with total average annual growth rates of 70.20% and 91.53%, respectively. Notably, chest X-ray imaging showed total and average annual growth rates of 63.89% and 89.41%, respectively.Conclusions:From 2018 to 2022, X-ray imaging examinations displayed significantly fluctuating frequencies with an overall decline trend in the 38 medical institutions. In contrast, the CT scans showed increased frequencies, with chest CT scans displaying an increased frequency and proportion. This necessitates ensuring the justification of CT scans.

Objective:To investigate the status and diagnostic reference levels (DRLs) of adult CT radiation dose based on survey result from some hospitals in Beijing.Methods:From September to December 2023, the survey results for 50 hospitals were collected in Beijing, including 47 tertiary hospitals and 3 second grade general hospitals. The CT data sets in total of 20 items including head (sequential scanning), head (spiral scanning), head perfusion, sinus, neck, chest, chest (low dose scanning), abdomen, pelvis, abdomen-pelvis, chest-abdomen-pelvis, lumbar spine, CT urography, coronary CTA (retrospective), coronary CTA (prospective), head CTA, neck CTA, aorta CTA, leg CTA and knee were collected on clinical commonly used CT scanners with annual qualified state inspection. For each item, radiation dose data was collected continuously and randomly for up to 50 cases for every CT scanner. Using the volume CT dose index (CTDI vol) and dose length product (DLP) as dose parameters, the median value of each item in each hospital was obtained. The median CTDI vol and DLP values of all hospitals were arranged, and the local DRL of each item was set as the 75th percentile of the median values. The obtained DRLs were compared with the DRLs issued by domestic and international radiological protection organizations. Results:A total of 26 031 dose values of adult patients were collected and 25 996 dose values were left while 35 invalid values removed.For different CT users, CTDl vol, DLP and scanning phases were different for the same item. The five items with the highest CTDI were head perfusion, head sequential scanning, head spiral scanning, coronary CTA (retrospective mode), and sinus. The five items with the highest DLP were CTU, head perfusion, leg CTA, chest-abdomen-pelvis and aortic CTA. The CTDI vol of CTU was only 16.9 mGy (75th percentile), while the DLP was as high as 2 394.9 mGy·cm (75th percentile). The survey showed that the DRLs of most items in Beijing was lower than the national DRLs of domestic and foreign standards, and the DRLs of a small number of items were slightly higher. Conclusion:The current CT dose level in Beijing is not consistent with national DRLs released at home and abroad, so it is necessary to establish local DRLs according to the clinical status in Beijing.

Objective:To investigate the radiation dose levels of digital radiography (DR) in adult patients and explore the diagnostic reference level (DRL) of radiation dose in Beijing.Methods:Radiation dose data were collected from 39 medical institutions in Beijing on 18 930 DR examinations of chest anterior and lateral view, abdomen anterior and posterior view, abdomen standing view, cervical spine anterior and lateral view, lumbar spine anterior and lateral view, knee joint anterior and lateral view as well as 5 266 digital mammography (CC view and MLO view). For ordinary DR examinations, the incident air kinetic energy ( Ka, i), incident air specific kinetic energy area product ( PKA) and effective dose ( E) to the examined individuals were used for the investigation and estimation of radiation dose. For digital mammography, the average glandular dose (AGD) was calculated. DRLs should be set at the 75 th percentile of median values obtained in each medical institution. Results:The Ka, i, PKA and E of DRL for Chest (PA), Chest (lateral), abdominal(PA), abdominal (AP), Pelvic(AP), Cervical (AP), Cervical (lateral), Lumbar (AP), Lumbar (lateral), Knee joint (AP) and Knee joint (lateral) of conventional DR were 0.14, 0.31, 1.25, 2.18, 1.86, 0.51, 0.14, 2.97, 8.39, 0.37, 0.37 mGy, 159, 259, 1 917, 2 336, 2 867, 312, 301, 3 500, 3 359, 269, 255 mGy·cm 2, 0.03, 0.05, 0.20, 0.43, 0.23, 0.03, 0.02, 0.47, 0.35, <0.001, <0.001 mSv. The DRLs for digital mammography were calculated to be 1.87 mGy (CC view), 1.94 mGy (MLO view) and 3.99 mGy (accumulated for one examination). Conclusions:The radiation dose from DR examinations is relatively low. In clinical practice, the selection of imaging parameters should be further standardized on the basis of the local DRL.

Objective:To investigate devices for radiodiagnosis used in medical institutions in Beijing, China, as well as radiation workers and the devices′ application frequencies, in order to provide data support for determining radiation protection measures and allocating resources for clinical radiodiagnosis.Methods:In October 2023, questionnaires were distributed to the members of the Radiation Technology Branch of the Beijing Medical Association who work in medical institutions at different levels across varying districts of Beijing. The collected data included information about devices for radiodiagnosis and radiation workers, as well as the application frequencies of various medical X-ray imaging devices during 2018-2022, in 38 medical institutions of Level 3 Grade A, Level 3, and Level 2 in 14 municipal districts of Beijing. Then, the collected data were organized using the Microsoft Power BI software to form report models, followed by the statistical analysis of data on the devices, radiation workers, and application frequencies were using the RStudio software.Results:The 38 medical institutions in Beijing possess 591 devices for radiodiagnosis and 2 018 staff in the departments of radiology, including 1 037 radiologic technologists and 738 physicians, with 1.77 technologists and 1.26 physicians arranged for a single device on average. From 2018 to 2022, among all examinations of radiodiagnosis, computed tomography (CT) scans showed the highest frequencies, with total and average annual growth rates of 138.06% and 108.40%, respectively. Specifically, chest CT scans exhibited total and average annual growth rates of 225.20% and 122.50%, respectively. X-ray imaging ranked second in application frequency, with total average annual growth rates of 70.20% and 91.53%, respectively. Notably, chest X-ray imaging showed total and average annual growth rates of 63.89% and 89.41%, respectively.Conclusions:From 2018 to 2022, X-ray imaging examinations displayed significantly fluctuating frequencies with an overall decline trend in the 38 medical institutions. In contrast, the CT scans showed increased frequencies, with chest CT scans displaying an increased frequency and proportion. This necessitates ensuring the justification of CT scans.

Objective:To investigate the effect of different scanning modes, detector width and location in detector on high and low contrast resolution of wide-detector CT image.Methods:The Catphan600 phantom with high and low contrast resolution modules was scanned with GE Revolution CT at the same CTDI vol. The scans were performed with the detector widths of 40, 80 and 160 mm for sequential scanning mode and with the detector width/pitch combinations of 40 mm/0.516, 40 mm/0.984, 80 mm/0.508 and 80 mm/0.992 for spiral scanning mode. The resolution modules were placed at the adjacent region between two sequential scans, central and foot side edge in the longitudinal scanning range seperately. The subjective evaluation of the high and low contrast resolution was performed by two radiologists. Results:The high contrast resolution was 8 LP/cm at adjacent region between two sequential scans with the detector width of 80 mm or 160 mm in sequential scanning mode, and at the pitch of 0.5 in spiral scanning mode, while it was 7 LP/cm for the rest of detector combinations. The distinguishable diameter was 3 mm at 1% low contrast resolution at foot side edge with the detector widths of 80 mm or 160 mm in the sequential scanning mode, and it was 2 mm for all the other conditions. The distinguishable diameter was 2 mm at 1% low contrast resolution with the detector width of 40 mm and pitch 0.516 in the spiral scanning mode and it was worse with the wider detector and larger pitch.Conclusions:For the wide-detector CT, scanning mode, detector width, location in detector and pitches will affect the high and low contrast resolution to some degree. Appropriate selection should be done according to actual needs in clinical practice.

Objective To establish a simple and practical superparamagnetic immunochromatographic test strip for rapidly monitoring human serum level of CA72-4. Methods Water-soluble carboxylated super-paramagnetic nanoparticles were prepared with a modified one-step hydrothermal synthesis method. Magnetic probe was prepared by immobilizing specific antibody (mAb1) onto the surface of nanoparticles. Following with optimization and assembly of the test strip , we evaluated sensitivity , specificity , stability of this method for serum CA72-4 detection. Results The optimized test strip provided not only the qualitative results, but also the high sensitivity quantitative detection through stable magnetic signal. The detection limit was 0.83 IU/mL. One hundred clinical samples ( 70 positive and 30 negative ) were measured to assess these test strips with high sensitivity (99%) and high specificity (93%). The test strip and magnetic signal possessed high stability. Conclusion A rapid and quantitative detection of CA72-4 by the test strip was accomplished. This method is rapid, sensitive and quantitative, possessing great potential in large sample screening or in-home testing.

BACKGROUND:Bisphosphonates that can suppress osteoclast activity strongly is a powerful inhibitor for bone resorption, which has been reported to have good effects in the treatment of fibrous dysplasia.
OBJECTIVE:To evaluate the clinical effect of surgical treatment combined with bisphosphonate therapy in the treatment of fibrous dysplasia.
METHODS: Fifteen patients with fibrous dysplasia of the long bone were subjected to surgical treatment and oral bisphosphonate therapy postoperatively. Limb pain, limb function, local X-ray manifestations and blood alkaline phosphatase activity were observed before and at 3, 6, 12, 24 months after treatment. The therapeutic effects were evaluated using modified Macnab standards.
RESULTS AND CONCLUSION:Al the 15 patients were folowed up for more than 24 months, and their pain symptoms were significantly relieved after the combined treatment of surgery and bisphosphonates, excelent in 12 cases and effective in 1 case, and the total efficiency was 100%. X-ray films showed that the density slightly decreased in operation areas after 3 months, but at 6 months after treatment, the cortical bone was thickened and the marrow cavity density increased in the operation areas, and non-focal zone was continuously enlarged. No fractures and recurrence were found in al patients. At 6 months after treatment, the serum alkaline phosphatase activity decreased significantly (P < 0.05). The results suggest that surgical operation with bisphosphonate treatment for bone fibrous dysplasia can effectively inhibit the bone resorption, promote bone formation, increase the intensity of the lesion, reduce fractures and recurrence rate, so as to achieve a better therapeutic effect in clinic.

Objective To explore the effects on image quality and dose reduction to the lens when using bismuth shielding in head and neck MSCT.Methods The standard phantom and the cadaveric head with none,1,2 and 3 layers of bismuth shielding were scanned with protocols of brain,temporal bone and paranasal sinuses using a 16-MDCT scanner.The organ dose to the lens in each scanning was measured with thermoluminescence dosimeters(TLD).The above scanning with sinus protocol was repeated with a sponge with thickness of 5,10,15 and 20 mm placed between the shielding and phantom/head.The CT attenuation of phantom with the distance of 2,4,6 and 8 cm to shielding were measured.The image quality was subjectively evaluated by 2 physicians.Results The organ doses of the lens with protocols of brain,temporal bone and sinuses were 24.31,27.60 and 20.01 mGy,respectively.The doses were decreased significantly when using bismuth shielding.With the increase of the shield gap,the degree of dose reduction was reduced,but the increasing degree of CT attenuation significantly reduced.Using 2-layer and 3-layer bismuth shield in brain and temporal bone CT scan,the radiation doses were reduced by 47.1％ and 59.1％,respectively while maintaining the diagnostic image quality.Using 1-layer shield without gap and 2-layer shield with 1.5 cm gap in sinus CT,the radiation doses were reduced by 31.5％ and 34.5％,respectively.Conclusions Reasonable usage of bismuth shielding can effectively reduce the radiation dose to the lens of eye in head and neck MSCT.