智能冠状动脉运动追踪平台Snapshot Freeze在冠状动脉CT血管成像中的应用  

Study of cardiac motion-correction algorithm—Snapshot Freeze in coronary CT angiography

作　　者：高建华[1] 陈晓霞[1] 王贵生[1] 韩文娟[1] 赵国全[1] 

机构地区：[1]武警总医院CT科,北京100039

出　　处：《中国医学影像技术》2014年第12期1822-1826,共5页Chinese Journal of Medical Imaging Technology

摘　　要：目的探讨智能冠状动脉运动追踪平台Snapshot Freeze（SSF）在冠状动脉CT血管成像（CCTA）中的应用价值。方法连续选取61例患者,使用Discovery CT750 HD Freedom进行冠状动脉扫描,扫描后分别使用和不使用SSF重建,得到A、B两组图像;根据扫描实时心率将患者分为低心率组（心率≤70次/分,n=34）,中高心率组（心率71～80次/分,n=14）和高心率组（心率〉80次/分,n=13）。对比分析A、B组间和不同心率组间的图像质量差异。结果除左主干（S5）外,B组冠状动脉各节段图像质量评分均优于A组（P均〈0.05）;S5段剔除评分为5分者后,其余7例B组图像质量均优于A组（P=0.008）;未使用SSF重建时不可诊断的42个节段经用SSF重建后全部可用于诊断。未使用SSF重建的不同心率组间除S7、S9段外,其余各节段图像质量评分差异均有统计学意义（P均〈0.05）,图像质量随心率增加而下降;使用SSF重建后,不同心率组间各节段图像质量评分差异均无统计学意义（P均〉0.05）。未使用SSF重建的右冠状动脉中段（S2）在15段中评分最低（2.88±0.91）分,S3次之（3.65±1.32）分,且S2在低心率组亦有17例出现移动伪影影响其评估;使用SSF重建后,S2、S3移动伪影显著改善,评分分别提升至（4.32±0.59）分和（4.49±0.59）分,均满足诊断需求。结论 SSF能够有效地纠正高心率及心率波动导致的冠状动脉血管移动伪影,优化CCTA图像质量,尤其对右冠状动脉移动伪影有显著意义。Objective To analyze the effect of cardiac motion-correction algorithm—Snapshot Freeze（SSF）on image quality in coronary CT angiography（CCTA）.Methods Sixty-one consecutive patients underwent CCTA on a Discovery CT 750 HD Freedom.The images of every patient were reconstructed with a standard algorithm（group A）and with the SSF algorithm（group B）.Patients were further divided into 3subgroups based on their heart rates：low heart rate（≤70bpm,n=34）,medium heart rate（71—80bpm,n=14）and high heart rate（〉80bpm,n=13）.The image quality with 2reconstructions among the various heart rate subgroups was evaluated.Results Image quality scores in group B were significantly higher than those in group A in every segment（all P〈0.05）except the left main coronary artery（S5）.For S5,if patients with image quality score of 5were excluded,image quality score in group B were higher than that in group A（P=0.008）.The 42non-diagnostic segments in group A were fully recovered in group B.There were differences in image quality scores for all the segments except S7 and S9in group A with the standard reconstruction.However,there was no image quality difference for these segments in group B with motion correction（all P〉0.05）.With the standard reconstruction（group A）,the middle right coronary artery segment（S2）had the lowest image quality score of 2.88±0.91,followed by S3 with 3.65±1.32.The motion artifacts in S2 and S3were dramatically reduced with motion correction in group B and image scores were improved to the respective 4.32±0.59 and 4.49±0.59.Conclusion The cardiac motion correction algorithm（SSF）can effectively overcome the influence of high heart rate on image quality in CCTA,improves the image quality and success rate in cardiac imaging.It is especially effective in significantly correcting for the motion artifacts in the middle right coronary artery.

关 键 词：冠状血管 体层摄影术 X线计算机 图像质量 SNAPSHOT Freeze 

分 类 号：R814.42[医药卫生—影像医学与核医学] R543.3[医药卫生—放射医学]