CAJ | 학술논문

目的比较双源CT冠状动脉CT成像中应用等渗低浓度对比剂与迭代重建时,与常规浓度及滤波反投影(FBP)成像时的碘摄入量、图像质量及辐射剂量.方法连续收集50例(A组)拟行冠状动脉CT检查者行常规浓度对比剂及FBP重建,再连续收集50例(B组)使用迭代重建及等渗低浓度对比剂进行冠状动脉CT检查,2组均采用前瞻性心电门控序列扫描模式.由2名有经验的医师对2组图像质量进行双盲法评分,利用Kappa检验比较观察者间评分的一致性;采用两独立样本t检验比较2组患者的有效辐射剂量、平均CT值、图像噪声、信噪比(SNR)、对比信噪比(CNR)、图像质量评分等,并对2组患者的总碘量以及碘注入率进行比较.结果 100例受检者均成功完成检查.2组患者一般资料及扫描参数之间比较差异无统计学意义.A、B组冠状动脉图像质量主观评分分别为(4.4±0.7)、(4.3±0.8)分,2组间差异无统计学意义(t=0.924,P＞0.05).2名医师评分的一致性较高(Kappa值为0.887,P＜0.01).所有患者图像CT值均高于300 HU,A、B组图像平均CT值分别为(386.1±51.5)、(384.1±77.1)HU,差异无统计学意义(t=0.157,P＞0.05).2组间SNR、CNR差异无统计学意义(P值均＞0.05).B组的有效辐射剂量为(1.09±0.19) mSv,较A组[(2.85±0.59) mSv]降低约61.8％,2者间差异有统计学意义(t=20.260,P＜0.01).A组总碘量以及碘注入率分别为21.0 g、17.5g/s,B组分别为16.2 g、13.5 g/s,B组较A组总碘量以及碘注入率均下降了22.9％.结论使用迭代重建和等渗低浓度对比剂进行低剂量冠状动脉CT检查时,可以大幅度降低辐射剂量和碘摄入量,可达到原高浓度、高电压而无迭代重建时的图像质量.
목적 비교쌍원CT관상동맥CT성상중응용등삼저농도대비제여질대중건시,여상규농도급려파반투영(FBP)성상시적전섭입량、도상질량급복사제량.방법 련속수집50례(A조)의행관상동맥CT검사자행상규농도대비제급FBP중건,재련속수집50례(B조)사용질대중건급등삼저농도대비제진행관상동맥CT검사,2조균채용전첨성심전문공서렬소묘모식.유2명유경험적의사대2조도상질량진행쌍맹법평분,이용Kappa검험비교관찰자간평분적일치성;채용량독립양본t검험비교2조환자적유효복사제량、평균CT치、도상조성、신조비(SNR)、대비신조비(CNR)、도상질량평분등,병대2조환자적총전량이급전주입솔진행비교.결과 100례수검자균성공완성검사.2조환자일반자료급소묘삼수지간비교차이무통계학의의.A、B조관상동맥도상질량주관평분분별위(4.4±0.7)、(4.3±0.8)분,2조간차이무통계학의의(t=0.924,P＞0.05).2명의사평분적일치성교고(Kappa치위0.887,P＜0.01).소유환자도상CT치균고우300 HU,A、B조도상평균CT치분별위(386.1±51.5)、(384.1±77.1)HU,차이무통계학의의(t=0.157,P＞0.05).2조간SNR、CNR차이무통계학의의(P치균＞0.05).B조적유효복사제량위(1.09±0.19) mSv,교A조[(2.85±0.59) mSv]강저약61.8％,2자간차이유통계학의의(t=20.260,P＜0.01).A조총전량이급전주입솔분별위21.0 g、17.5g/s,B조분별위16.2 g、13.5 g/s,B조교A조총전량이급전주입솔균하강료22.9％.결론 사용질대중건화등삼저농도대비제진행저제량관상동맥CT검사시,가이대폭도강저복사제량화전섭입량,가체도원고농도、고전압이무질대중건시적도상질량.
Objective To compare the iodine intake,image quality and radiation dose of dual-source CT coronary artery angiography between the low concentration isotonic contrast agent with iterative reconstruction technique of sinogram affirmed iterative rEconstruction (SAFIRE) and common concentration contrast agent with filtered back projection (FBP).Methods One hundred patients [58 men,42 women; age:(62± 11)y] were enrolled in this study.Fifty consecutive patients (Group A) were scanned with FBP and common concentration contrast agent and another 50 consecutive patients (Group B) were scanned with low concentration isotonic contrast agent and iterative reconstruction technique.The image quality were assessed by two experienced radiologists with a double blinded fashion in a five score scale.The attenuation of coronary artery,scan time,imaging noise,signal-to-noise ratio (SNR),contrast-to-noise ratio (CNR),radiation dose and iodine intake between these two groups were compared using two sample t test.The observer agreement for image quality was calculated using Kappa statistics.Results All examinations were completed successfully.There was no statistical difference (P＞0.05) between two groups in clinical characteristics and scan parameters.There was no statistical difference for the mean subjective image quality of group A (4.4±0.7) and group B (4.3±0.8) (t=0.924,P＞0.05).The Kappa value between two radiologists was 0.887 (P＜0.01)on image quality.The mean attenuation of coronary artery segments was higher than 300 HU,especially in group A (386.1±51.5) HU,which was slightly higher than the group B (384.1±77.1) HU,but there was no statistical difference (t=0.157,P＞0.05).The SNR and CNR in two groups did not have significant differences (P＞0.05).The total iodine and iodine injection rates were 21.0 g,17.5 g/s in Group A and 16.2 g,13.5 g/s in Group B,respectively.The iodine intake was decreased by 22.9％ in Group B.The effective radiation dose in Group B (1.09±0.19) mSv was significantly (t=20.260,P＜0.01) lower than that in Group A (2.85±0.59) mSv,with the radiation dose reduced by 61.8％.Conclusion Low concentration isotonic contrast agent and iterative reconstruction technique can significantly reduce the radiation dose and iodine intake in CT coronary artery angiography and achieve the same image quality using common concentration contrast agent with FBP.