IDream与ASiR迭代重建算法对主动脉CT血管造影图像质量改善比较效果研究  

Comparative analysis of the quality improvements between IDream and ASiR iterative reconstruction algorithms for CTA image on aorta

作　　者：牛磊 张淳 谢汝明 NIU Lei;ZHANG Chun;XIE Ru-ming(Department of Medical Engineering,Beijing Ditan Hospital Capital Medical University,Beijing 100015,China;不详)

机构地区：[1]首都医科大学附属北京地坛医院医学工程处,北京100015 [2]首都医科大学附属北京地坛医院放射科,北京100015

出　　处：《中国医学装备》2023年第10期24-30,共7页China Medical Equipment

摘　　要：目的:探讨IDream与GE ASiR两种迭代重建算法对主动脉CT血管造影(CTA)检查图像质量改善效果的差异。方法:前瞻性选取在医院行主动脉CTA检查的40例患者,根据患者检查时所使用的设备,将其分为观察组和对照组,每组20例。观察组使用Insitum CT768型设备检查,对照组使用GELight SpeedVCT型设备检查。两组设置相同的扫描参数,均采用管电压120 kV和自动管电流(mA)控制技术。观察组分别采用滤波反投影(FBP)重建算法和IDream迭代算法级别1~5档位重建图像,对照组同样分别采用FBP重建及ASi R迭代重建算法10%、30%、50%、70%和90%档位重建图像。对两组的FBP重建及迭代重建各档位图像进行客观评价,对比两组主动脉感兴趣区的CT值及噪声(SD)值、信噪比(SNR)和对比噪声比(CNR),计算两组各迭代档位重建针对FBP重建的降噪百分比,评价拟合斜率迭代算法降噪效果的客观指标。比较两组辐射剂量指标中CT容积剂量指数(CTDI_(vol))、剂量长度乘积(DLP)和有效剂量(ED)。结果:观察组随着FBP重建及IDream迭代算法5个级别升高(1、2、3、4和5),SD依次显著降低,差异具有统计学意义(t=10.13,t=14.83,t=13.20,t=12.36,t=14.90;P<0.05)。对照组随着FBP重建及ASi R的5个档位升高(10%、30%、50%、70%和90%),SD依次显著降低,差异具有统计学意义(t=18.671,t=18.096,t=18.191,t=17.034,t=17.071;P<0.05)。观察组的拟合斜率大于对照组;两组辐射剂量评价指标CTDI_(vol)、DLP和ED比较,差异均无统计学意义(Z=-1.953,Z=-1.621,Z=-1.621;P>0.05)。结论:在同等辐射剂量水平下,IDream迭代技术与ASi R重建技术相比,对降低图像噪声及提升图像质量效果更为显著,具有较高临床实用价值。Objective:To investigate the difference of the effects of quality improvements between two kinds of iterative reconstruction algorithms(IDream and GE ASiR)for the images of compute tomography angiography(CTA)examination on aorta.Methods:A total of forty patients who underwent CTA examination on aorta in hospital were prospectively collected and they were divided into observation group and control group according to the used equipment of patients in examination,with 20 cases in each group.The observation group was examined by InsitumCT 768 equipment,and the control group was examined by GE LightSpeed VCT equipment.The same scanning parameters were set in the two groups,and both two groups adopted the tube voltage of 120 kV and the automatic mA control technique.The observation group used respectively filtered back projection(FBP)reconstruction algorithm and IDream iterative algorithm to reconstruct images at levels 1-5.The control group used respectively FBP reconstruction and ASiR iterative reconstruction algorithm to reconstruct the images at 10%,30%,50%,70%and 90%levels.The images of each level of FBP reconstruction and iterative reconstruction of two groups were objectively evaluated,and the CT value,noise(SD)value,signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of the region of interest of aorta were compared between the two groups.The percentage of noise reduction of each iterative reconstruction level for FBP reconstruction was calculated in the two groups,and the objective indicator of the effect of noise reduction of the iterative algorithm of fitting slope was evaluated.The CT volume dose index(CTDIvol),dose length product(DLP)and effective dose(ED)of the radiation dose indicators were compared between the two groups.Results:In the observation group,with the increasing of the level of FBP reconstruction and IDream iterative algorithm(1,2,3,4 and 5),the SD decreased significantly in turn,and the differences were statistically significant(t=10.13,t=14.83,t=13.20,t=12.36,t=14.90,P<0.05),repectivel

关 键 词：迭代重建 主动脉CT血管造影(CTA) 体层摄影术 图像质量控制 

分 类 号：R816.2[医药卫生—放射医学]