能谱CT消除肺动脉CTA中上腔静脉伪影的应用价值  

The application value of Gemstone spectral CT for reducing beam-harding artifacts of the superior vein in the CTPA

作　　者：史自锋 程琦[1] 赵娜[1] 金启安[1] 李丹[1] 许实成[1] 赵英明[1] 何峰[1] 

机构地区：[1]安徽医科大学附属省立医院影像科,合肥230001

出　　处：《安徽医科大学学报》2014年第2期210-213,共4页Acta Universitatis Medicinalis Anhui

摘　　要：目的研究能谱CT最佳单能量成像在消除肺动脉CT血管成像(CTPA)中上腔静脉造影剂硬化伪影方面的应用价值。方法对50例肺动脉CTA检查者行能谱扫描(GSI),在ADW4.5工作站以上腔静脉伪影为背景获得最佳对比噪声比(CNR)单能量显示肺动脉图像,对单能量图像和混合能量图像分别从上腔静脉伪影和肺动脉干的CT值和噪声值、图像的相对伪影指数(AI)和图像质量主观评分及噪声的相对比7个方面进行比较,采用配对t检验和Kappa检验及均数的参数估计进行分析及最佳keV值95%置信区间的估计。结果最佳CNR单能量组上腔静脉伪影平均CT值低于混合能量组(P<0.01),肺动脉干平均CT值单能量组高于混合能量组(P<0.01);肺动脉干平均噪声值(SD值)单能量组低于混合能量组(P=0.021);相对AI(上腔静脉伪影CT值/肺动脉CT值)单能量组低于混合能量组(P<0.01);图像质量主观评分单能量组平均分高于混合能量组(Kappa=0.180,P=0.031),噪声值的相对比较(肺动脉干SD值/上腔静脉伪影SD值)单能量组低于混合能量组(P<0.05)。上腔静脉伪影平均噪声值(SD值)单能量组与混合能量组比较差异无统计学意义。结论能谱CT最佳单能量成像技术,能有效消除上腔静脉造影剂硬化伪影,明显提高肺动脉CTA图像的质量。Objective To evaluate the value of monochromatic images of Gemstone spectral CT for reducing the beam-hardening artifacts cause by contrast media of the superior vein in CT pulmonary angiography（ CTPA） . Meth-ods 50 patients of CTPA were scaned with Gemstone spectral imaging （ GSI ） examination, in workstation of ADW4.5 using the superior vein artifacts vein as the background for best contrast to noise ratio（ CNR）;obtaining monochromtic images to show the pulmonary artery;comparing the monochromatic images with mixture energy image from seven aspects as the superior vein artifacts and pulmonary CT number and noise,artifact index （ AI） and sub-jective scores of image quality and relative noise;using paired t test and Kappa test and parameter estimation of mean for best keV number analysis and 95% interval estimation. Results The superior vein artifacts average CT number of monochromatic images group was below mixture energy image group （ P＆lt;0.01 ） . Pulmonary average CT number of monochromatic images group was higher than mixture energy group（P＆lt;0.01）. The pulmonary artery av-erage noise number （ SD number ） of monochromatic images group was lower than mixture energy group （ P =0.021 ） . Relative AI of two groups （ the superior vein artifacts CT number/pulmonary CT number ） monochromatic images group was lower than mixture energy group（P＆lt;0.01）. The subjective average score of image monochromat-ic images group points was higher than mixture energy group（Kappa=0.180,P=0.031）. Relative noise number （ pulmonary SD number/the superior vein artifacts SD number） monochromatic images group was lower than mix-ture energy group（P＆lt;0.05）. Those 6 aspects all had statistical significance. Average noise number （SD umber） of the superior vein artifacts monochromatic images group and mixture energy group had no statistical significance. Conclusion The best single energy spectrum CT imaging technology can effectively reduce the beam-hardening ar-tifacts caus

关 键 词：能谱成像 体层摄影术 X线计算机 肺动脉 伪影 

分 类 号：R814.42[医药卫生—影像医学与核医学]