安徽医科大学学报2017，Vol.52Issue(6)：887-891,5.DOI:10.19405/j.cnki.issn1000-1492.2017.06.024
大尺度非局部均值伪影抑制技术对提高低剂量腹部CT图像质量的价值研究
Study on the value of large-scale non-local mean artifacts suppression technique in improving the quality of low-dose CT images
摘要
Abstract
Objective To evaluate the feasibility of the artifact suppressed-large neighborhood nonlocal means for improving the quality of low dose abdominal CT images.Methods With institutional review board approval 26 patients who underwent routine-dose and low-dose abdominal CT examination were enrolled.The routine dose and low dose abdominal raw data were reconstructed with FBP,40% ASIR respectively,and the reconstructed thickness of image was 0.625 mm.Two reconstruction algorithms of low dose data were processed the artifact suppressed large neighborhood nonlocal means.The application of processing station was used to analyze the CT images.The image noises were measured,and the noise,contrast to noise ratio(CNR) and the signal to noise ratio(SNR) of the liver,spleen and abdominal aorta were compared.The subjective evaluation was described for the abdominal image quality.Radiation dose by CT dose index volumes(CTDIvol) and dose length product(DLP) were recorded,and effective dose(ED) and the average reduction rate was calculated.Results For the image quality of the abdominal,the AS-LNLM low dose images had lower noise values,higher CNR and SNR than conventional and low dose images without using this technique(P<0.05).The conventional dose images had lower noise values,higher CNR and SNR than low-dose images(P<0.05).For the FBP reconstruction algorithm,the subjective scores of low dose images used AS-LNLM technology and low dose images without using this technique were approximately(4.23±0.43) and (1.95±0.72)(P<0.05).For the 40% ASIR reconstruction algorithm,the subjective scores of low dose images used AS-LNLM technology and low dose images without using this technique were approximately(4.36±0.49) and (2.18±0.66)(P<0.05).The subjective scores of conventional dose images of FBP and 40% ASIR were approximately (4.73±0.46) and (4.82±0.40),respectively.CTDIvol,DLP and ED of low-dose CT images were (1.84±0.01) mGy,(4.96±2.63) mGy/cm and (0.74±0.04) mSv,and for conventional dose CT images were (7.61±0.03) mGy,(204.18±11.19) mGy/cm and (3.06±0.17) mSv,respectively.Conclusion Compared with conventional scanning,AS-LNLM can significantly reduce the scanning dose and improve the image CNR and SNR,and the quality of image can meet the diagnostic requirements.关键词
体层摄影技术/X线计算机/大尺度非局部均值伪影抑制/低剂量扫描/滤波反投影法/自适应统计迭代重建/伪影抑制Key words
X-ray computed tomography/artifact suppressed large neighborhood nonlocal means/low dose scan/filtered back projection/adaptive statistical iterative reconstruction/artifacts suppressed分类
医药卫生引用本文复制引用
余广海,吴越,刘斌,陈阳,刘文冬,刘福军,王胜峰..大尺度非局部均值伪影抑制技术对提高低剂量腹部CT图像质量的价值研究[J].安徽医科大学学报,2017,52(6):887-891,5.基金项目
安徽省科技计划项目(编号:1604a0802079) （编号:1604a0802079）
