低对比剂浓度结合最佳单能量图像对心肌双能量图像质量的影响  

The effects of low contrast agent concentration combined with optimal monochromatic energy image on myocardial dual energy image quality

作　　者：田蔚莉 潘存雪 刘文亚 党军 王海涛 张娟 Tian Weili;Pan Cunxue;Liu Wenya;Dang Jun;Wang Haitao;Zhang Juan(Imaging Center, First Hospital, Xinjiang Medical University, Urumqi 830054, Chin)

机构地区：[1]新疆医科大学第一附属医院影像中心,乌鲁木齐830054

出　　处：《中华放射学杂志》2018年第2期140-143,共4页Chinese Journal of Radiology

基　　金：新疆维吾尔自治区自然科学基金面上项目（2013211A083）

摘　　要：目的探讨在双源CT双能量冠状动脉CT成像（CCTA）中，低对比剂浓度结合最佳单能量图像对心肌图像质量的影响。方法前瞻性连续纳入2016年1月至6月新疆医科大学第一附属医院，临床疑诊为冠心病拟行双源双能量CCTA检查的60例患者，采用随机数字表法分为A、B两组，每组30例。均行冠状动脉双源CT双能量扫描，A、B组对比剂分别采用含碘量为370、320 mg/ml的碘帕醇，其他参数一致。将原始图像分别重组出A、B两组的常规混合能量图像及60、65、70、75、80、85、90 keV单能量图像，分别为A1～A8、B1～B8组。分别测量A1～A8、B1～B8组图像的CT值、噪声、信噪比（SNR）和对比噪声比（CNR），筛选出最佳单能量图像组。采用秩和检验比较A1～A8组间、B1～B8组间CT值、噪声、SNR及CNR的差异；采用独立样本t检验比较A1组与B5组、A5组与B5组各项指标的差异。结果A1～A8组间、B1～B8组间CT值、噪声、SNR及CNR的差异均有统计学意义（P均〈0.05）。A5组CNR和SNR高于A1组，且A5组图像噪声低于A1组，差异均有统计学意义（P均〈0.05），A5组（75 keV）图像为最佳单能量图像。B5组左心室侧壁的SNR、CNR高于B1组，噪声低于B1组，差异均有统计学意义（P均〈0.05），B5组（75 keV）图像为最佳单能量图像。A1和B5组间的图像噪声差异有统计学意义（t=6.59，P〈0.05），SNR、CNR差异均无统计学意义（t值分别为－1.63、－1.94，P均〉0.05）。A5组与B5组间的图像的噪声、SNR、CNR差异均无统计学意义（t值分别为1.45、－1.53、－1.89，P均〉0.05）。结论应用含碘320 mg/ml对比剂行CCTA心肌检查时，单能量扫描75 keV水平图像和常规含碘370 mg/ml对比剂混合能量图像质量相当，在满足临床诊断需求的同时，有效地减少了对比剂用量。ObjectiveTo investigate the effects of low contrast agent concentration and optimal monoenergetic image on myocardial image quality in dual source, dual energy coronary CT angiography （CCTA）.MethodsSixty patients, who were clinically suspected of coronary heart disease and referred to perform dual energy CCTA examination, were prospectively collected between January and June 2016 in the first affiliated hospital of Xinjiang Medical University and then randomly divided into two groups with thirty cases in each group. Dual-energy CCTA was performed in both groups with the same parameters expect the iodine contrast agent concentration. The iopamidol concentrations were 370 and 320 mg/ml for groups A and B, respectively. The raw images of the two groups were reconstructed to get conventional mixed energy images and 60, 65, 70, 75, 80, 85, 90 keV single energy images, respectively labeled as group A1 to A8 and group B1 to B8. The CT attenuation, noise, signal-to-noise ratio （SNR） and contrast to noise ratio （CNR） were measured in images from groups A1 to A8 and B1 to B8. And the optimal monoenergetic image set was selected. Rank sum test was used to compare the CT value, noise, SNR and CNR between groups A1 to A8 and B1 to B8. The differences of above-mentioned parameters between A1 and B5 group, A5 group and B5 group were compared by independent sample t test.ResultsThe differences of CT value, noise, SNR and CNR between groups A1 and A8, B1 and B8 were statistically significant （P〈0.05）. The CNR and SNR of group A5 were significantly higher than that of group A1, and the image noise of group A5 was lower than that of group A1 （all P〈0.05）, and the images of A5 group （75 keV） were the optimal monoenergetic image. The SNR and CNR of the left ventricular lateral wall in group B5 were significantly higher than those in group B1, and the noise was lower than that in group B1 （all P〈0.05）, and the image of B5 group （75 keV） was the optimal monoenergetic image. The difference of image

关 键 词：造影剂 体层摄影术 X线计算机 对比研究 

分 类 号：R816.2[医药卫生—放射医学]