胸部低剂量CT扫描中迭代重建算法与滤波反投影算法肺结节检出率和准确性比较  

Comparison of pulmonary nodule detection rate and accuracy in low-dose chest CT between iterative reconstruction algorithm and filtered back projection algorithm

作　　者：王杰[1] 曾勇明[1] 彭刚[1] 郁仁强[1] 孙静坤[1] 金瑞[1] 

机构地区：[1]重庆医科大学附属第一医院放射科,重庆400016

出　　处：《吉林大学学报（医学版）》2014年第5期1098-1103,I0006,共7页Journal of Jilin University：Medicine Edition

基　　金：重庆市卫生局科研基金资助课题(08-2-29)

摘　　要：目的：比较胸部CT中原始数据域迭代重建（SAFIRE）算法与滤波反投影（FBP）算法重建图像肺结节检出率的差异，评价其检出的准确性。方法：在新双源 CT上预设80、100和120 kV 3组管电压值，采用自动毫安秒技术对置入模拟肺结节的仿真胸部体模进行扫描，分别用 SAFIRE（等级1～5）及 FBP算法重建图像，比较SAFIRE（等级1～5）与FBP胸部CT重建图像中模拟肺结节的检出率，并测量其直径及CT值。结果：相同管电压胸部CT扫描， SAFIRE（等级1～5）与 FBP模拟肺结节检出率比较差异无统计学意义（P＞0.05）， SAFIRE （等级3）模拟结节直径偏差度小于 FBP，且 SAFIRE（等级3）与 FBP模拟结节的平均 CT值比较差异无统计学意义（P＞0.05）；100 kV模拟结节检出率与120 kV模拟结节检出率相同，80 kV模拟结节（-800 HU和3 mm）检出率低于120 kV模拟结节检出率；随着管电压降低、模拟结节直径减小、模拟结节密度降低，模拟结节直径偏差度增大。结论：与 FBP比较， SAFIRE算法对于不同密度、不同大小肺结节检出有相同的能力，并有助于肺结节的准确显示，可用于低剂量CT肺癌筛查方案。Objective To compare the differences of pulmonary nodule detection rates between iterative reconstruction （sinogram affirmed iterative reconstruction,SAFIRE）algorithm and filtered back projection （FBP） algorithm in chest CT, and to evaluate the detection accuracy.Methods Three groups of tube voltage values of 80,100,and 120 kV were defaulted on the new dual-source CT,with automatic mAs care dose 4D technology, the chest phantom with simulated pulmonary nodules was scanned, then the images were reconstructed with FBP and SAFIRE （grade 1-5 ）,respectively. The detection rates of simulated pulmonary nodules in the chest CT images reconstructed of SAFIRE （grade 1-5 ）and FBP were compared, and their diameters and CT values were measured.Results With the same tube voltage, no significant difference was found in the detection rate of simulated pulmonary nodules between SAFIRE （grade 1-5 ）and FBP （P〉0.05 ）, the diameter deviation of simulated nodules of SAFIRE （grade 3 ）was less than FBP, and the difference in the average CT value of the simulated nodules between SAFIRE （grade 3）and FBP was not statistically significant （P〉0.05）;the simulated nodule detection rate of 100 kV was equivalent to the detection rate of 120 kV,the simulated nodule （-800 HU and 3 mm ）detection rate of 80 kV was less than that of 120 kV;as the tube voltage reduced,or simulated nodule diameter decreased,or the density of simulated nodule reduced,the nodule’s diameter deviation was increased. Conclusion Compared with FBP,the capabilities of SAFIRE in pulmonary nodule detection in different densities and different sizes are same,and SAFIRE algorithm is helpful for accurate displaying of pulmonary nodules,and it can be used for low-dose CT lung cancer screening program.

关 键 词：体层摄影术 X线计算机 肺结节 图像重建 计算机辅助 

分 类 号：R734.2[医药卫生—肿瘤]