自适应统计迭代重建技术在低剂量CT结肠成像中息肉检出能力的评价  

Discussion of the detection ability of ASIR-V technique on polyps in CTC with low-dose

作　　者：刘晓冬[1] 刘爱连[1] 刘义军[1] 付维利[2] 刘静红[1] 方鑫[1] 赵莹[1] 徐明哲[1] 袁刚[1] LIU Xiao-dong;LIU Ai-lian;LIU Yi-jun(Department of Radiology,The First Affiliated Hospital of Dalian Medical University,Dalian 116011,China)

机构地区：[1]大连医科大学附属第一医院放射科,辽宁大连116011 [2]大连市友谊医院肝胆外二科,辽宁大连116001

出　　处：《中国医学装备》2020年第12期40-44,共5页China Medical Equipment

摘　　要：目的:评价不同水平自适应统计迭代重建(ASIR-V)算法对提高CT结肠造影(CTC)息肉检出率及其降低辐射剂量的价值。方法:选用离体猪结肠获得模拟息肉30个,按息肉直径(D)不同分为1~5 mm组、5~10 mm组和10~15 mm组,每组息肉10个。使用Revolution CT在管电压120 k Vp及不同管电流条件下扫描,应用6种不同权重(0、10%、30%、50%、70%和90%)ASIR-V算法进行图像重建。由两名医师进行息肉检出评分,并计算息肉检出率,比较其检出评分的一致性,采用线性回归分析息肉大小、管电流及ASIR-V算法权重变化与息肉检出率的相关性。统计息肉全部检出的最低辐射剂量,计算辐射剂量的降低幅度。结果:两名医师息肉检出评分一致性好(kappa=0.831);管电流及ASIR-V权重变化与息肉检出评分呈显著正相关(r=0.884,r=0.861;P<0.05)。息肉为1~15 mm时,当管电流为30 mA、权重为50%时ASIR-V算法重建与全部息肉检出率显著相关(r=0.677,r=0.644;P<0.05);息肉大小与检出率显著相关(r=0.688,P<0.05)。1~5 mm组息肉全部检出最低管电流为30 mA,权重为50%时ASIR-V算法重建与息肉检出率显著相关(r=0.924,P<0.05)。5~10 mm组息肉全部检出的最低管电流为30 mA,权重为30%时ASIR-V算法重建。管电流为10 mA或30 mA时,随ASIR-V算法权重增高,检出率提高。10~15 mm组的息肉检出,所有条件下检出率均达100%。当管电流为30 mA时,有效剂量为0.61 mSv,较50 mA(1.02 mSv)时降低67%。结论:应用ASIR-V算法可提高结肠息肉检出率,并有效降低辐射剂量,为低剂量CT结肠成像筛查提供了可能。Objective:To evaluate the values of adaptive statistical iterative reconstruction-veo(ASIR-V)algorithm so as to improve detection rate of computed tomography colonography(CTC)on polyp and reduce radiation dose.Methods:The in vitro pig colon was selected to obtain the simulated polyp(30 cases),and these polyps were divided into 1-5mm group,5-10mm group and 10-15 mm group according to the different diameter(D),with 10 polyps in each group.Used Revolution CT to scan under 120 kVp tube voltage and different tube current conditions.Images were reconstructed with six different weight(0,10%,30%,50%,70%and 90%)ASIR-V algorithm.Two doctors performed polyp detection scores,and calculated the polyp detection rate,and compared the consistency of the two observers for detection scores.And Linear regression was adopted to analyze the correlation between the weight changes in polyp size,tube current and ASIR-V algorithm and the detection rate of polyp.And the lowest radiation dose of all detected polyps was counted by statistic method,and the reduction range of radiation dose was calculated.Results:The consistence of polyp detection scores of two doctors were favorable(kappa=0.831).The changes of tube current and ASIR-V weight were significantly positively correlative with the polyp detection score(r=0.884,r=0.861,P<0.05).The ASIR-V algorithm reconstruction was significantly correlative with the detection rate of all polyps when the polyp size was 1-15 mm,the tube current was 30 mA and the weight was 50%(r=0.677,r=0.644,P<0.05).The polyp size was significantly correlative with the detection rate(r=0.688,P<0.05).The lowest tube current detected all polyps was 30 mA in 1-5 mm group,and the ASIR-V algorithm reconstruction was significantly correlative with polyp detection rate when the weight was 50%(r=0.924,P<0.05).The lowest tube current detected all polyps was 30 mA in 5-10 mm group,and the ASIR-V algorithm was used for reconstruction when the weight was 30%.The detection rate increased with the enhancing of ASIR-V algorithm we

关 键 词：计算机体层成像(CT) 自适应统计迭代重建(ASIR-V) 算法 CT结肠造影(CTC) 

分 类 号：R816.5[医药卫生—放射医学]