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1.
Korean Journal of Radiology ; : 502-512, 2021.
Artigo em Inglês | WPRIM | ID: wpr-902401

RESUMO

Objective@#To objectively and subjectively assess and compare the characteristics of monoenergetic images [MEI (+)] and polyenergetic images (PEI) acquired by dual-energy CT (DECT) of patients with breast cancer. @*Materials and Methods@#This retrospective study evaluated the images and data of 42 patients with breast cancer who had undergone dual-phase contrast-enhanced DECT from June to September 2019. One standard PEI, five MEI (+) in 10-kiloelectron volt (keV) intervals (range, 40–80 keV), iodine density (ID) maps, iodine overlay images, and Z effective (Z eff) maps were reconstructed. The contrast-to-noise ratio (CNR) and the signal-to-noise ratio (SNR) were calculated. Multiple quantitative parameters of the malignant breast lesions were compared between the arterial and the venous phase images. Two readers independently assessed lesion conspicuity and performed a morphology analysis. @*Results@#Low keV MEI (+) at 40–50 keV showed increased CNR and SNR breast lesion compared with PEI, especially in the venous phase ([CNR: 40 keV, 20.10; 50 keV, 14.45; vs. PEI, 7.27; p < 0.001], [SNR breast lesion: 40 keV, 21.01; 50 keV, 16.28; vs.PEI, 10.77; p< 0.001]). Multiple quantitative DECT parameters of malignant breast lesions were higher in the venous phase images than in the arterial phase images (p < 0.001). MEI (+) at 40 keV, ID, and Z eff reconstructions yielded the highest Likert scores for lesion conspicuity. The conspicuity of the mass margin and the visual enhancement were significantly better in 40-keV MEI (+) than in the PEI (p = 0.022, p = 0.033, respectively). @*Conclusion@#Compared with PEI, MEI (+) reconstructions at low keV in the venous phase acquired by DECT improved the objective and subjective assessment of lesion conspicuity in patients with malignant breast lesions. MEI (+) reconstruction acquired by DECT may be helpful for the preoperative evaluation of breast cancer.

2.
Korean Journal of Radiology ; : 502-512, 2021.
Artigo em Inglês | WPRIM | ID: wpr-894697

RESUMO

Objective@#To objectively and subjectively assess and compare the characteristics of monoenergetic images [MEI (+)] and polyenergetic images (PEI) acquired by dual-energy CT (DECT) of patients with breast cancer. @*Materials and Methods@#This retrospective study evaluated the images and data of 42 patients with breast cancer who had undergone dual-phase contrast-enhanced DECT from June to September 2019. One standard PEI, five MEI (+) in 10-kiloelectron volt (keV) intervals (range, 40–80 keV), iodine density (ID) maps, iodine overlay images, and Z effective (Z eff) maps were reconstructed. The contrast-to-noise ratio (CNR) and the signal-to-noise ratio (SNR) were calculated. Multiple quantitative parameters of the malignant breast lesions were compared between the arterial and the venous phase images. Two readers independently assessed lesion conspicuity and performed a morphology analysis. @*Results@#Low keV MEI (+) at 40–50 keV showed increased CNR and SNR breast lesion compared with PEI, especially in the venous phase ([CNR: 40 keV, 20.10; 50 keV, 14.45; vs. PEI, 7.27; p < 0.001], [SNR breast lesion: 40 keV, 21.01; 50 keV, 16.28; vs.PEI, 10.77; p< 0.001]). Multiple quantitative DECT parameters of malignant breast lesions were higher in the venous phase images than in the arterial phase images (p < 0.001). MEI (+) at 40 keV, ID, and Z eff reconstructions yielded the highest Likert scores for lesion conspicuity. The conspicuity of the mass margin and the visual enhancement were significantly better in 40-keV MEI (+) than in the PEI (p = 0.022, p = 0.033, respectively). @*Conclusion@#Compared with PEI, MEI (+) reconstructions at low keV in the venous phase acquired by DECT improved the objective and subjective assessment of lesion conspicuity in patients with malignant breast lesions. MEI (+) reconstruction acquired by DECT may be helpful for the preoperative evaluation of breast cancer.

3.
Chongqing Medicine ; (36): 2907-2909, 2014.
Artigo em Chinês | WPRIM | ID: wpr-455247

RESUMO

Objective To evaluate the value of 320 row CT upper abdominal computed tomography angiography (CTA) in the follow up of transjugular intrahepatic portosystemic shunt(TIPSS) .Methods 21 cases after TIPSS therapy underwent upper ab-dominal CTA .Post-processing images ,including MPR ,VR ,MIP ,and CPR ,were used to determine the position and patency of the stent .The best images of the portal veins were obtained .Results Among the 21 cases ,CPR image clearly demonstrated endovascu-lar stent thrombosis in 3 cases(14 .29% ) with stent occlusion and 1 case(4 .76% ) with stent stenosis ;there were no stent stenosis or occlusion in 17 cases(80 .95% ) ,their CPR image showed the contrast agent was filled completely in the stent and no low-density thrombosis was found .The best phase of the portal vein was 45 s .Conclusion 320 row CT upper abdominal CTA can clearly dis-play the stent position and patency situation in patients ,therefore ,should be regarded as the first choice for the follow-up of patients after TIPSS therapy .

4.
Journal of Environment and Health ; (12)1993.
Artigo em Chinês | WPRIM | ID: wpr-540606

RESUMO

Objective To establish a method of GS-MS for determination of polychlorinated biphenyls (PCBs) in human cerumen. Methods The PCBs in cerumen samples was separated by n-hexane extraction, liquid-liquid extraction separation and column chromatography purification, then was analyzed quantitatively by gas chromatography and affirmed qualitatively by mass spectroscopy. Results The detection limit, average recovery rate and precision of this method were 0.15 ?g/g fat, 92.1% and 3.0%-4.6% (n=12) respectively. The contents of PCBs in 90 cerumen samples collected in polluted and control areas were detected. The levels(0.00-18.42 ?g/g fat) of PCBs in cerumen collected in polluted area were significantly higher than that in the control area(P

5.
Journal of Environment and Health ; (12)1992.
Artigo em Chinês | WPRIM | ID: wpr-544960

RESUMO

Objective To investigate the distribution and environmental pollution of dioxin-like polychlorinated biphenyls(PCBs) in a place of disused transformer and other electronic waste disassembled. Methods The ambient air, aerosol, water, soil and vegetable samples were collected to analyze the dioxin-like PCBs level with isotope internal standards and HRGC-HRMS techniques. Results The concentration of dioxin-like PCBs in ambient air was 4 031.77-4 942.34 pg/m3(namely 1.832-2.666 pg TEQ/m3), while in aerosol it was 325.45-3 499.77 pg/m3(0.370 9-1.536 3 pg TEQ/m3). In the soil sample, the value was 2 316.59-19 100.30 pg/g(1.358-15.264 pg TEQ/g) dry weight. In water it was 5.731-237.640 ng/L(2.585-73.046 pg TEQ/L). In vegetable it was 1 078.45-1 620.04 pg/g(0.778 3-1.126 2 pg TEQ/g) wet weight. In all air, aerosol, soil, water and vegetable samples, the content of PCB-118 was the most. PCB-126 had the highest TEQ value. In non-ortho PCBs, PCB-77 was of maximum content. In mono-ortho PCBs, PCB-118 was the most, and the followings were PCB-105, PCB-156 and PCB-167. All the 12 kinds of PCBs were investigated in all samples except PCB-169 absent in ambient air. Conclusions The investigated area around the disassembly of obsolete solid waste has been badly contaminated by dioxin-like polychlorinated biphenyls(PCBs), and PCBs already exist in the vegetables. According to the results of the present paper, some further studies should be carried out to evaluate the toxic effects on food and people health.

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