摘要
目的分析滤波反投影算法与低剂量迭代算法在肺结节CT筛查中的差异。方法采用回顾性分析,选取本院85例行CT筛查的肺结节患者临床资料,均行滤波反投影算法扫描,其中20例患者另行低剂量迭代算法重建图像,比较这两种重建方法的肺结节信噪比、对比信噪比、肺组织信噪比和小结构可见性、密度分辨率、空间分辨率评分等差异。结果相比滤波反投影算法,低剂量迭代算法iDose 1~3级的对比信噪比、肺组织信噪比、肺结节信噪比均明显下降(P<0.05),而iDose 4~7级的对比信噪比、肺组织信噪比、肺结节信噪比与滤波反投影算法比较,差异均无统计学意义(P>0.05)。低剂量迭代算法iDose 1~4级小结构可见性评分与滤波反投影算法比较,差异均无统计学意义(P>0.05);iDose 5~7级小结构可见性评分均低于滤波反投影算法评分(P<0.05)。两种重建方法在密度分辨率和空间分辨率评分上的比较,差异均无统计学意义(P>0.05)。结论在64排螺旋CT肺结节筛查中,低剂量迭代算法薄层重建图像中iDose 4级可能为最优水平,其图像质量与滤波反投影算法图像较接近,同时可明显减少辐射剂量。
Objective To analyze the difference between filtered back projection algorithm and low dose iterative algorithm in CT screening of pulmonary nodules.Methods A retrospective study was carried out to collect the clinical data of 85 patients with pulmonary nodules screened by CT in our hospital,all of them were scanned by filter back projection algorithm,and 20 of them were reconstructed by low dose iterative algorithm.The differences of signal-to-noise ratio,contrast signal-to-noise ratio,signal-to-noise ratio of lung tissue and small structure visibility,density resolution and spatial resolution score between the two methods were compared.Results Compared with the filter back projection algorithm,the contrast signal-to-noise ratio,lung tissue signal-to-noise ratio and lung nodule signal-to-noise ratio of iDose 1~3 algorithm decreased significantly(P<0.05),while the contrast signal-to-noise ratio,lung tissue signal-to-noise ratio and lung nodule signal-to-noise ratio of iDose 4~7 algorithm had no significant difference(P>0.05).There was no significant difference(P>0.05)between the low-dose iterative algorithm iDose 1~4 small structure visibility score and the filter back projection algorithm(P<0.05),and the iDose 5~7 small structure visibility score was lower than the filter back projection algorithm(P<0.05).There was no significant difference between the two reconstruction methods in density resolution and spatial resolution score(P>0.05).Conclusion In 64 slice spiral CT pulmonary nodule screening,iDose4 may be the optimal level in the thin-layer reconstruction image of low dose iterative algorithm,and its image quality is close to that of filter back projection algorithm,and radiation dose can be significantly reduced.
作者
木拉提·木合买提
玉苏甫·肉孜
夏迎洪
任永芳
MUHEMATI Mulati;ROUZI Yusufu;XIA Yinghong;REN Yongfang(Department of Radiology, Uygur Autonomous Region, People’s Hospital of Xinjiang, Urumqi 830001, P.R.China)
出处
《医学影像学杂志》
2020年第11期2010-2013,共4页
Journal of Medical Imaging
关键词
肺结节
体层摄影术
X线计算机
滤波反投影算法
低剂量迭代算法
Pulmonary nodules
Tomography,X-ray computed
Filtered back projection algorithm
Low-dose iterative algorithm
