目的:通过比较在不同管电压、不同浓度对比剂的条件下肺动脉成像的影像质量以及患者所接受的辐射剂量,探讨"双低"技术肺动脉成像的可行性。方法:将60例临床怀疑肺动脉栓塞的患者分为C、L1、L2 3组,扫描条件:C组为120 k V、350...目的:通过比较在不同管电压、不同浓度对比剂的条件下肺动脉成像的影像质量以及患者所接受的辐射剂量,探讨"双低"技术肺动脉成像的可行性。方法:将60例临床怀疑肺动脉栓塞的患者分为C、L1、L2 3组,扫描条件:C组为120 k V、350 mg I/ml,L1组为100 k V、350 mg I/ml,L2组为100 k V、270 mg I/ml。3组管电流均为500 m A,对比剂用量、生理盐水用量和流速一致,分别为25 ml、40 ml、4.5 ml/s。应用SPSS 19.0统计学软件,对比分析肺动脉节段、上腔静脉、升主动脉的CT值,肺动脉主干噪声,图像质量以及容积扫描的辐射剂量。结果:各肺动脉主干及其分支显示清晰,满足诊断要求。L1组肺动脉主干及其分支CT值均高于C组,图像噪声大于C组,辐射剂量小于C组,差异均有统计学意义(P<0.01)。L2组肺动脉主干及其分支CT值与C组相当,差异无统计学意义(P>0.05);图像噪声大于C组,辐射剂量小于C组,差异均有统计学意义(P<0.01)。L2组肺动脉主干及其分支CT值均小于L1组,差异有统计学意义(P<0.01);图像噪声、辐射剂量与L1组相当,差异无统计学意义(P>0.05)。结论:低辐射剂量、低浓度对比剂可用于肺动脉CT成像,并且具有明显的优势。展开更多
目的探讨颈部CTA检查中进行64排CT "双低"扫描模式的应用研究。方法方便选择2015年6月—2016年2月来该院进行颈部CTA检查者90例,根据随机数字表法分为对照组和观察组,每组45例,观察组进行64排CT"双低"扫描模式,300 ...目的探讨颈部CTA检查中进行64排CT "双低"扫描模式的应用研究。方法方便选择2015年6月—2016年2月来该院进行颈部CTA检查者90例,根据随机数字表法分为对照组和观察组,每组45例,观察组进行64排CT"双低"扫描模式,300 mgI/mL碘海醇对比剂,100 k V管电压,对照组进行常规64排CT扫描模式,即350 mgI/mL碘海醇对比剂,120 k V管电压,由两名资质较高的影像科医师评价图像质量,比较两组的对比噪声比(CNR)、信噪比(SNR)、噪声、CT值等临床指标情况;比较两组的颈部动脉血管1分节段、2分节段、3分节段、4分节段的图像质量情况。结果观察组的对比噪声比(CNR)、信噪比(SNR)、噪声、CT值等临床指标情况分别为(40.2±6.3)、(40.6±7.9)、(9.1±2.3)、(388.6±40.3)HU,对照组分别为(58.9±10.8)、(69.7±15.7)、(7.4±0.5)、(490.8±60.2)HU,差异有统计学意义(t=10.03,11.11,4.85,9.46,P<0.05);而观察组与对照组的颈部动脉血管1分节段、2分节段、3分节段、4分节段的图像质量比较,差异无统计学意义(P>0.05)。结论颈部CTA检查中应用64排CT"双低"扫描模式可显著降低患者所受的碘总量和辐射剂量,同时可获得较佳的图像质量。展开更多
AIM: To evaluate the image quality of hepatic multidetector computed tomography(MDCT) with dynamic contrast enhancement. METHODS: It uses iodixanol 270 mg/m L(Visipaque 270) and 80 kVp acquisitions reconstructed with ...AIM: To evaluate the image quality of hepatic multidetector computed tomography(MDCT) with dynamic contrast enhancement. METHODS: It uses iodixanol 270 mg/m L(Visipaque 270) and 80 kVp acquisitions reconstructed with sinogram affirmed iterative reconstruction(SAFIRE?) in comparison with a standard MDCT protocol. Fiftythree consecutive patients with known or suspected hepatocellular carcinoma underwent 55 CT examinations, with two different four-phase CT protocols. The first group of 30 patients underwent a standard 120 kVp acquisition after injection of Iohexol 350 mg/m L(Accupaque 350~?) and reconstructed with filtered back projection. The second group of 25 patients underwent a dual-energy CT at 80-140 kVp with iodixanol 270. The 80 kVp component of the second group was reconstructed iteratively(SAFIRE?-Siemens). All hyperdense and hypodense hepatic lesions ≥ 5 mm were identified with both protocols. Aorta and portal vessels/liver parenchyma contrast to noise ratio(CNR) in arterial phase, hypervascular lesion/liver parenchyma CNR in arterial phase, hypodense lesion/liver parenchyma CNR in portal and late phase were calculated in both groups.RESULTS: Aorta/liver and focal lesions altogether/liver CNR were higher for the second protocol(P = 0.0078 and 0.0346). Hypervascular lesions/liver CNR was not statistically different(P = 0.86). Hypodense lesion/liver CNR in the portal phase was significantly higher for the second group(P = 0.0107). Hypodense lesion/liver CNR in the late phase was the same for both groups(P = 0.9926).CONCLUSION: MDCT imaging with 80 kVp with iterative reconstruction and iodixanol 270 yields equal or even better image quality.展开更多
文摘目的:通过比较在不同管电压、不同浓度对比剂的条件下肺动脉成像的影像质量以及患者所接受的辐射剂量,探讨"双低"技术肺动脉成像的可行性。方法:将60例临床怀疑肺动脉栓塞的患者分为C、L1、L2 3组,扫描条件:C组为120 k V、350 mg I/ml,L1组为100 k V、350 mg I/ml,L2组为100 k V、270 mg I/ml。3组管电流均为500 m A,对比剂用量、生理盐水用量和流速一致,分别为25 ml、40 ml、4.5 ml/s。应用SPSS 19.0统计学软件,对比分析肺动脉节段、上腔静脉、升主动脉的CT值,肺动脉主干噪声,图像质量以及容积扫描的辐射剂量。结果:各肺动脉主干及其分支显示清晰,满足诊断要求。L1组肺动脉主干及其分支CT值均高于C组,图像噪声大于C组,辐射剂量小于C组,差异均有统计学意义(P<0.01)。L2组肺动脉主干及其分支CT值与C组相当,差异无统计学意义(P>0.05);图像噪声大于C组,辐射剂量小于C组,差异均有统计学意义(P<0.01)。L2组肺动脉主干及其分支CT值均小于L1组,差异有统计学意义(P<0.01);图像噪声、辐射剂量与L1组相当,差异无统计学意义(P>0.05)。结论:低辐射剂量、低浓度对比剂可用于肺动脉CT成像,并且具有明显的优势。
文摘目的探讨颈部CTA检查中进行64排CT "双低"扫描模式的应用研究。方法方便选择2015年6月—2016年2月来该院进行颈部CTA检查者90例,根据随机数字表法分为对照组和观察组,每组45例,观察组进行64排CT"双低"扫描模式,300 mgI/mL碘海醇对比剂,100 k V管电压,对照组进行常规64排CT扫描模式,即350 mgI/mL碘海醇对比剂,120 k V管电压,由两名资质较高的影像科医师评价图像质量,比较两组的对比噪声比(CNR)、信噪比(SNR)、噪声、CT值等临床指标情况;比较两组的颈部动脉血管1分节段、2分节段、3分节段、4分节段的图像质量情况。结果观察组的对比噪声比(CNR)、信噪比(SNR)、噪声、CT值等临床指标情况分别为(40.2±6.3)、(40.6±7.9)、(9.1±2.3)、(388.6±40.3)HU,对照组分别为(58.9±10.8)、(69.7±15.7)、(7.4±0.5)、(490.8±60.2)HU,差异有统计学意义(t=10.03,11.11,4.85,9.46,P<0.05);而观察组与对照组的颈部动脉血管1分节段、2分节段、3分节段、4分节段的图像质量比较,差异无统计学意义(P>0.05)。结论颈部CTA检查中应用64排CT"双低"扫描模式可显著降低患者所受的碘总量和辐射剂量,同时可获得较佳的图像质量。
文摘AIM: To evaluate the image quality of hepatic multidetector computed tomography(MDCT) with dynamic contrast enhancement. METHODS: It uses iodixanol 270 mg/m L(Visipaque 270) and 80 kVp acquisitions reconstructed with sinogram affirmed iterative reconstruction(SAFIRE?) in comparison with a standard MDCT protocol. Fiftythree consecutive patients with known or suspected hepatocellular carcinoma underwent 55 CT examinations, with two different four-phase CT protocols. The first group of 30 patients underwent a standard 120 kVp acquisition after injection of Iohexol 350 mg/m L(Accupaque 350~?) and reconstructed with filtered back projection. The second group of 25 patients underwent a dual-energy CT at 80-140 kVp with iodixanol 270. The 80 kVp component of the second group was reconstructed iteratively(SAFIRE?-Siemens). All hyperdense and hypodense hepatic lesions ≥ 5 mm were identified with both protocols. Aorta and portal vessels/liver parenchyma contrast to noise ratio(CNR) in arterial phase, hypervascular lesion/liver parenchyma CNR in arterial phase, hypodense lesion/liver parenchyma CNR in portal and late phase were calculated in both groups.RESULTS: Aorta/liver and focal lesions altogether/liver CNR were higher for the second protocol(P = 0.0078 and 0.0346). Hypervascular lesions/liver CNR was not statistically different(P = 0.86). Hypodense lesion/liver CNR in the portal phase was significantly higher for the second group(P = 0.0107). Hypodense lesion/liver CNR in the late phase was the same for both groups(P = 0.9926).CONCLUSION: MDCT imaging with 80 kVp with iterative reconstruction and iodixanol 270 yields equal or even better image quality.
