摘要
目的探讨80 kVp管电压联合迭代模型重建技术（IMR）并采用MPR重组在结肠CT造影中应用的可行性与价值。方法选取经肠镜证实为结肠癌或结肠息肉的32例患者,采用低辐射剂量（80 kV,150 mAs）进行CT结肠造影检查,以滤波反投影重建算法（FBP）和混合迭代重建技术（iDOSE4）及迭代模型重建技术（IMR level 1-3）分别对原始数据进行重建,后行MPR三维重组。图像质量的客观评估指标：图像噪声（SD）、图像信噪比（SNR）及对比噪声比（CNR）、有效辐射剂量。图像质量的主观评估：采用4分法对结肠病变图像整体质量进行主观评分。结果图像质量客观评估结果,SD依FBP、iDOSE4、IMR（1-3）顺序逐渐降低,组间差异明显（P〈0.01）,组内两两比较,FBP、iDOSE4、IMR之间差异明显（P〈0.01）,IMR 1、IMR 2、IMR 3之间SD无明显统计学差异;SNR及CNR依FBP、iDOSE4、IMR（1-3）顺序逐渐升高,组间差异显著（P〈0.01）,具有显著统计学差异;组内两两比较,FBP与iDOSE4之间差异无统计学意义,而IMR 1、IMR 2、IMR 3之间差异显著（P〈0.01）,具有明显统计学差异。图像质量主观评分结果,低对比分辨率以IMR重建得分最高,iDOSE4、FBP得分依次降低;病灶边缘锐利度评分中,IMR 1评分最高,FBP最低;图像失真评分中,FBP图像得分最高,依FBP、iDOSE4、IMR（1-3）顺序依次降低;诊断信心评分中,IMR 1图像得分最高。IMR 1图像的整体主观评分最高,两名医师主观评分一致性良好,Kappa值在0.62-0.86之间。结论 80 k V低剂量结肠CT扫描联合迭代模型重建技术及MPR三维重组,由于其较低的辐射剂量和较高的图像质量,可作为结肠镜检查的重要补充检查手段,用于正常体型人群结肠病变的诊断与筛查。
Objective To explore the feasibility and value of computed tomography colonography with 80 kVp tube voltage combined with knowledge-based iterative reconstruction（ IMR） algorithm and MPR reconstruction. Methods 32 patients confirmed by colonoscopy for colon carcinoma or colonic polyps were selected,in patients with body mass index（ BMI）of 19-24 kg/m2,using low radiation dose（ 80 kVp,150 mAs） CT enhanced scanning. The raw data were reconstructed by filtered back projection（ FBP） and hybrid iterative reconstruction（ iDOSE4） and knowledge-based iterative reconstruction（ IMR level1-3）. The original images were reconstructed by MPR 3 D reconstruction. Objective evaluation indexes of image quality include image noise（ SD）,signal-to-noise ratio（ SNR）,contrast-to-noise ratio（ CNR）,and effective radiation dose.Subjective evaluation of image quality： subjective grading of colonic lesion images was performed by 4 points method. Results In the objective evaluation results of image quality,SD decreased gradually in the order of FBP,iDOSE4 and IMR（ 1-3）,and the difference of FBP,iDOSE4 and IMR was obvious,P〈0. 01. There was no statistically significant difference in SD between IMR 1,IMR 2 and IMR 3. SNR and CNR increased gradually in the order of FBP,iDOSE4 and IMR（ 1-3）,the difference of FBP,iDOSE4 and IMR was significant,P〈0. 01. There was no significant difference between the two groups in the comparison of FBP and iDOSE4,but there was significant difference between IMR 1,IMR 2 and IMR 3,and P〈0. 01. Subjective evaluation of image quality： Low contrast resolution with IMR reconstruction scored the highest,iDOSE4 and FBP decreased gradually. In the margin sharpness score,the IMR1 score was the highest,the FBP score was the lowest. On mage distortion score,the FBP score was the highest,and the score decreased gradually in the order of FBP,iDOSE4 and IMR（ 1-3）. In the diagnostic confidence score,IMR 1 was the highest. The overall subjective score of IMR1 images was the
作者
张妤
张征宇
胡春洪
李勇刚
ZHANG Yu;ZHANG Zhengyu;HU Chunhong;et al.(Department of Radiology, the Affiliated No. 1 Hospital of Soochow University, Suzhou, Jiangsu Province 215006, P. R. China)
出处
《临床放射学杂志》
CSCD
北大核心
2018年第4期703-707,共5页
Journal of Clinical Radiology
基金
国家自然科学基金面上项目(编号:81671743)
2016年江苏省高层次卫生人才“六个一工程”项目(编号:LGY2016035)
关键词
CT结肠成像
辐射剂量
迭代模型重建算法
图像质量
Computed tomography colonography Radiation dosage Iterative model reconstruction Image quality
