双能量CT非线性融合技术对胰腺占位显示的初步研究  

Study of Reconstruction Parameters of Non-Linear Image Blending in Dual Energy CT Imaging for Pancreatic Mass

作　　者：王慧慧[1] 刘婧[1] 刘建新[1] 曹新鸣[1] 王子岩[1] 王霄英[1] 

机构地区：[1]北京大学第一医院医学影像科,北京100034

出　　处：《临床放射学杂志》2017年第8期1195-1198,共4页Journal of Clinical Radiology

摘　　要：目的探讨双能量CT非线性融合技术对胰腺占位显示的情况及最优重组参数。方法回顾性分析32例胰腺占位患者的双能量CT(80 k Vp/Sn140 k Vp)增强扫描图像。将胰腺实质期图像数据进行不同方式的非线性融合重组,融合中心(BC)为胰腺占位与胰腺正常实质CT值的平均值,融合宽度(BW)分别设置为0、50 HU、100HU、200 HU、500 HU,最终得到5组非线性融合图像。以常规线性融合(M=0.3)的图像为参考,比较各组非线性融合图像中病灶的对比度和对比噪声比(CNR),并进行主观评价。结果所有非线性融合图像质量均高于参考图像。实性占位BW=50 HU、囊性占位BW=0时CNR值最高(P<0.001),主观评价结果示读片者倾向对实性占位选择BW=0~100 HU重建图像,对囊性占位选择BW=0~200 HU重建图像。结论非线性融合技术显示胰腺占位优于常规线性融合图像,推荐使用较窄的融合宽度(BW=0~100 HU)进行重建。Objective To evaluate the image quality of dual-energy abdominal computed tomography（ DECT） with a non-linear image blending reconstruction algorithm as compared to the conventional linear blending reconstruction images.Methods Thirty-two patients suspected of pancrentic lesions（ 15 solid lesion and 17 cystic lesion） underwent dualsource,dual-energy abdominal CT（ 80 kVp/Sn140 kVp） examination. Conventional linear blending algorithm（ M = 0. 3）was used to reconstruct CT data of pancreatic parenchymal phase,which was taken as the reference image. Non-linear blending images of the pancreatic parenchymal phase were also obtained by using different reconstruction protocols. The blending center was set as the median value between the lesion and the normal pancreatic parenchyma with different blending width（ BW = 0,BW = 50,BW = 100,BW = 200 and BW = 500 HU,respectively）. Contrast of lesion,lesion CNR and image noise were calculated and compared with the reference image and various nonlinear blending images. Two radiologists assessed subjective image quality,lesion contrast and conspicuity and selected the preferred images. Results For solid lesions,the non-linear blending image sets with level width of BW = 0,BW = 50 and BW = 100 HU were estimated as the most preferred image sets. For cystic lesions,the non-linear blending image set with level width of BW = 0,BW = 50,BW = 100 and BW = 200 HU were estimated as the most preferred ones. There was no significant difference in noise of all images（ P = 0. 147）. CNR in non-linear blending image was significantly higher（ P〈0. 001 for both solid and cystic lesions） than that of reference image. Among non-linear blending images,CNR of solid lesion was the highest in BW = 50 HU without statistical difference compared with BW = 0 and BW = 100 HU（ P = 0. 819,0. 117）,and CNR of cystic lesion was the highest in BW = 0 HU without statistical difference compared with BW = 50 HU（ P = 0. 053）. Conclusion The non-linear blending images provide improved

关 键 词：双能量CT 线性融合 非线性融合 胰腺 

分 类 号：R735.9[医药卫生—肿瘤] R816.5[医药卫生—临床医学]