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Objective:To investigate the effect of adjusting density exposure steps on image quality and radiation dose in digital mammography.Methods:Using the automatic exposure control (AEC) mode of the digital mammography machine, five different gland thicknesses of 4.3, 5.3, 6.3, 7.3, and 8.3 cm were simulated by attaching 0, 1, 2, 3, and 4 PMMA plexiglass plates under the RMI-156 modal body, and the density exposure steps were adjusted to -3, -2, -1, 0, 1, 2, 3, and 4 for each thickness. The target/filter combination, tube voltage, tube current, incident body surface dose (ESD), incident surface air kerma (ESAK), half-value layer (HVL) and the average glandular dose displayed by the device (displayed AGD) were recorded at each step and thickness, and the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), figure of merit (FOM) and the calculated average glandular dose (calculated AGD) were calculated. Then, the display effects of simulated fibers, simulated calcifications and simulated masses within the modal body were scored subjectively, and the changes in image quality and radiation dose at different steps were analyzed, and the relationships between ESD and ESAK, displayed AGD and calculated AGD, and displayed AGD/ESD and calculated AGD/ESAK were analyzed. A linear fit was used for the steps with SNR, CNR, and FOM, and an exponential function curve fit was used for the steps with mAs, ESAK, and calculated AGD. The differences between ESD and ESAK, displayed AGD and calculated AGD, and displayed AGD/ESD and calculated AGD/ESAK were analyzed by paired-samples t test. Results:The CNR and SNR of mammographic images rose and fell by about 8% with each increase or decrease of one step. The scores of image simulated fibers, simulated calcifications, and simulated masses showed an overall upward trend with increasing steps, but there were still cases where the scores decreased with increasing grades. FOM varied from 97% to 104% at each grade with little variability. ESD, ESAK, displayed AGD, and calculated AGD, which could measure radiation dose, showed an exponential trend of increasing function with increasing steps, with a variation of about 63% to 165%. There were statistically significant differences ( t=-9.61, P=0.001) between ESD (15.14±10.08) and ESAK (16.66±11.07). However, there were no statistically significant differences ( t=1.20, P=0.240) between displayed AGD and calculated AGD, which were 3.66±2.18 and 3.61±1.99, respectively. Conclusions:The adjustment of density exposure steps can make the image quality change linearly and the radiation dose change exponentially with increasing speed, and the mode and magnitude of the adjustment are appropriately stable with high application value.
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Objective:To evaluate the effect of reducing mAs on image quality when different target/filter combinations are used in digital mammography.Methods:In different target/filter combinations, based on the mAs of automatic exposure control(AEC), the reduction of mAs by 10%, 20%, 30%, 40% and 50% respectively were used to expose the phantom with 4.4 cm thickness. The contrast to noise ratio(CNR), signal to noise ratio(SNR), figure of merit(FOM)and average glandular dose(AGD) of the resulting image were calculated. While the image quality was ensured, the optimal mAs and the corresponding AGD under the two target/filter combination were conducted by calculating the FOM. The image features of three tissues of phantom were subjectively evaluated, and the relationship between the calculated AGD and displayed AGD was compared. The mAs that meets the image quality requirements is corresponded with the density exposure gear, and the average values of the mAs for two method were calculated and compared.Results:In two targets/filters combinations, the displayed AGD was less than the calculated AGD, and Mo/Mo was underestimated by 22.5% to 23.7%. The calculated and displayed AGD values were statistically different ( F=4 982.86, 5 555.48, P<0.05). W/Rh was underestimated by 13.1% to 14.2%. The calculated and displayed AGD values were statistically different ( F=18 859.09, 15 973.55, P<0.05). In the Mo/Mo combination, when the mAs was reduced by 20%, the FOM could be increased by 9.6% for the maximum value, and the calculated AGD was decreased by 18.8%. In the W/Rh combination, when the mAs was reduced by 10%, the FOM was increased by 5.1% for the maximum value, and the calculated AGD was decreased by 11.9%. While the image quality was ensured, the mAs was reduced by 30% for evaluating simulated fibers, and by 20% for evaluating simulated specks in the two targets/filter combinations. For evaluating simulated masses, Mo/Mo combination reduced the mAs by 40%, and the W/Rh combination reduced the mAs by 30%. And the image quality scores in above were not significantly different from those in AEC method ( P>0.05). The density exposure gear(-1 to -3) could correspond with the reduced mAs(10%-30%). Conclusions:Under different target/filter combination, the tube mAs could be reduced when the image quality was ensured.
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Objective To review the research progress in new formulations of norcantharidin. Methods The foreign and domestic literature search in the new formulations of norcantharidin was conducted. The research and development of norcantharidin formulations were summarized and commented. Results The drug delivery systems, such as microspheres, nanoparticles, liposomes, and microemulsions, have great development potential as the new formulations for norcantharidin. Conclusion Norcantharidin is an excellent anti-tumor drug. The traditional injections and tablets have serious side effects in clinical application. The new formulations reduced the renal and urinary toxicity and side effects. Those formulations provided better therapeutic effects as target medication. Therefore, the new norcantharidin formulations have great development prospects.
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Objective To investigate the diagnostic value of full-field digital mammography (FFDM) combined with three-dimentional digital breast tomosynthesis (3D-DBT) in the lesions of dense breast mass. Methods A total of 121 patients with breast mass (135 lesions) in Shanxi Provincial People's Hospital from January 2018 to May 2018 were retrospectively analyzed. The differences of FFDM combined with 3D-DBT technique and FFDM alone in the diagnosis of dense breast mass lesions were compared and analyzed by using American Radiological Society's Breast Imaging Reporting and Data System (BI-RADS) grading diagnosis, and then the pathological results were compared. Results The sensitivity, accuracy rate and specificity of FFDM combined with 3D-DBT in the diagnosis of breast cancer among 135 lesions was 97.3％ (36/37), 80.0％ (108/135) and 73.5％ (72/98), respectively. The sensitivity, accuracy rate and specificity of FFDM in the diagnosis of breast cancer was 86.5％ (32/37), 70.4％ (95/135) and 64.3％ (63/98), respectively. Area under the receiver operating characteristic curve of FFDM combined with 3D-DBT was higher than that of FFDM alone (0.854 vs. 0.754). Compared with FFDM, mass diameter measured by 3D-DBT was close to the pathological results. The detection rates of mass, burr features and suspected malignant aggregation calcification by using FFDM combined with 3D-DBT were superior than those by using FFDM [100.0％ (72/72) vs. 81.9％ (59/72), 52.8％ (19/36) vs. 41.7％ (15/36), 75.0％ (27/36) vs. 66.7％ (24/36), respectively]. Conclusions For the focal mass of compact glands, compared with FFDM alone, the accuracy rate of the mass measurement, the detection rate of the suspected mass, the malignant mass burr, and themicro-calcification of aggregation treated by FFDM combined with 3D-DBT have been increased in a varying degree.
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Objective To evaluate the short-term effects of three-dimensional conformal radiotherapy (3D-CRT) associated with transcatheter arterial chemoembolization (TACE) in the treatment of primary hepatic carcinoma and 3D-CRT associated with chemotherapy in the treatment of metastatic hepatic carcinoma. Methods In 52 patients with primary hepatic carcinoma, first of all a single TACE was conducted. Then after an interval of 2 weeks, the conformal radiotherapy was given, with a radiation dose of 2~3 Gy every fraction, once daily or once every other day and 3~5 fractions every week. The total radiation dose to the target was 42.2~60.0 Gy (mean, 52.2 Gy). Afterwards, 2 additional TACEs were given after the radiotherapy. In 35 patients with metastatic hepatic carcinoma, chemotherapy was carried out for 1 treatment course firstly. Then 3D-CRT was employed. After the radiotherapy, another 2 courses of consolidating chemotherapy were administrated. The patient continued with the chemotherapy for additional 3 treatment courses (a total of 6 courses) if efficacy evaluation showed the patient had responded to the chemotherapy. Results The response outcomes were: complete remission (CR) 23 0% (20/87), partial remission (PR) 39 1% (34/87), stable disease (SD) 34 5% (30/87) and progressive disease (PD) 3 4% (3/87), the response rate (RR) being 62 1% (54/87). Conclusions 3D-CRT with TACE for primary hepatic carcinoma and 3D-CRT with chemotherapy for metastatic hepatic carcinoma offers high local control rates and good short-term effects.
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Objective To explore the adjustment of interleukin II combining lifein for CD+4 T lymphocyte, Th1 and Th2 of patients with malignant tumor. Methods CD+4 T lymphocyte were measured by flow cytometer. Th1 lymphocyte and Th2 lymphocyte were measured by ELISA. Thirty- eight patients with malignant tumor were enrolled in the study. Interleukin II were administered at the dose of 500 000 U, i.h Qd, from day 1 to day 5. Lifein were administered at the dose of 10mg/d, i.m Qd, from day 6 to day 21 or form day 6 to day 27. The count of CD+4 T lymphocyte, Th1 lymphocyte and Th2 lymphocyte were studied before treatment, 2 weeks and 1 month after treatment. Conduct ANOYA using SPSS software. Results The expression of CD+4 T lymphocyte in patients as with increase tendency. The counts of Th1 lymphocyte, Th2 lymphocyte and Th1/Th2 were not significantly different after treatment. Conclusions The dose of this treatment could enhance the count of CD+4 T, but it could not adjust the count of Th1 lymphocyte, Th2 lymphocyte. The target of treatment about interleukin II combining lifein for patients with malignant tumor is CD+4 T lymphocyte's other subsets.