摘要
目的评估双能量CT（DECT）肾脏成像线性融合方式（LB）中不同加权因子的混合能量图像质量,以确定双能量成像在肾癌诊断中的最佳加权因子。方法对32例肾癌患者行肾实质期双能量CT扫描,并将140 k V和80 k V两种能量图像进行不同加权因子下的线性融合,比较加权因子从0-1.0混合能量图像的噪声（SD）、信噪比（SNR）、对比噪声比（CNR）,并对加权因子分别为0、0.3-0.6的图像进行醒目度评分。结果图像SD在加权因子为0.3、0.4的混合能量图像中较低。图像的SNR和CNR在加权因子为0.4、0.5、0.6的三组混合能量图像中较高,在加权因子为0.6的混合能量图像上最高。加权因子分别为0、0.3、0.4、0.5、0.6的图像质量评分一致性较好,评分总体比较,差异有统计学意义（P〈0.05）,其中加权因子为0.6的混合能量图像评分最高。结论肾癌双能量扫描中加权因子为0.6的混合能量图像具有相对较低的SD和较高的SNR、CNR,为肾癌的诊断提供了良好的图像质量保证。
Objective To evaluate the effect of different energy-weighted factors on the CT image quality of dual-energy linear fusion imaging for the diagnosis of renal cell carcinoma so as to determine the best energy-weighted factor.Methods A total of 32 patients with renal cell carcinoma underwent dual-energy CT scanning in renal cortex phase.The images using 140 k V and 80 k V were input to computer for postprocessing,then 8 sets of mixed-energy images were made from 140 k V and 80 k V images with various methods.The background noise,signal-noise rate（ SNR） and contrast-noise ratio（ CNR） of renal cell carcinoma were determined.The results were compared between each other among 80 k V,0.3LB,140 k V images,which were obtained from mainframe and 8 sets mixed linear blending energy images.The image quality score was ranked among 0.0LB,0.3LB,0.4LB,0.5LB,0.6LB images.Results The noise of 0.3LB and 0.4LB images was lower,with the noise of 0.3LB images being the lowest and the noise of 80 k V images the highest.In image sets of0.4LB,0.5LB,0.6LB,the SNR and CNR were much higher,with 0.6LB image set being the highest.The results of image quality score evaluation in 0.0LB,0.3LB,0.4LB,0.5LB groups were essentially consistent with each other,and statistically significant difference existed between each other among these four groups（ P 〈0.05）,with the score of mixed-energy 0.6LB group being the highest.Conclusion Dual-energy CT scanning with 0.6LB can provide less noise and higher SNR and CNR images,which ensure the necessary image quality for the diagnosis of renal cell carcinoma.
出处
《临床放射学杂志》
CSCD
北大核心
2014年第11期1720-1724,共5页
Journal of Clinical Radiology
基金
宁夏科技公关项目
关键词
双能量
体层摄影术
X线计算机
肾癌
线性融合成像
Dual energy Tomography X-ray computed Renalcell carcinoma Linear blending imaging
