论文部分内容阅读
目的探讨冠状动脉追踪冻结技术(snapshot freeze,SSF)对冠状动脉多层螺旋CT血管成像图像质量的优化价值。方法回顾性分析北京军区总医院2013年3月~5月期间85例未服用控制心率药物的冠状动脉CTA检查患者影像学资料,应用SSF技术前后CT图像质量差异情况比较。患者按心率是否大于65次/min分为AB两组,其中A组26例,心率≤65次/min;B组59例,心率>65次/min。应用冠状动脉追踪冻结技术对冠状动脉图像进行处理,测量应用SSF技术前后,左冠状动脉前降支、左回旋支及右冠状动脉的血管轴截面、运动伪影及邻近脂肪的SD值,计算运动伪影指数(MAI)数值;并采用盲法由两名高年资主治医师对图像质量进行五分制评分,对评分结果进行比较及量化分析。结果 A组患者平均心率(58.5±5.69)次/min;MAI:使用SSF技术为(12.65±5.96),低于未使用SSF技术(None-SSF)(24.10±8.62),差异有统计学意义(P<0.05);主观图像评分:使用SSF技术为SSF(4.15±0.45),高于None-SSF(3.00±1.04),差异有统计学意义(P<0.05)。B组患者平均心率(77.73±9.67)次/min;MAI:使用SSF技术为(18.09±9.00),低于None-SSF(66.99±17.49),差异有显著统计学意义(P<0.01);主观图像评分使用SSF技术为(3.82±0.78),高于None-SSF(1.96±0.67),差异有显著统计学意义(P<0.01)。A组患者应用SSF处理后MAI平均下降48%,B组患者应用SSF处理后MAI平均下降73%,下降幅度明显大于A组。结论冠状动脉追踪冻结技术(SSF)可以提高冠状动脉CTA的图像质量,作用在患者心率超过65次/min时更为明显。
Objective To investigate the optimization of the coronary artery MSCT angiography image quality by using the snapshot freeze (SSF) technique. Methods A retrospective analysis of 85 patients with coronary artery CTA in Beijing Military Region General Hospital from March 2013 to May 2013 without coronary heart rate control was performed. The differences of CT images before and after application of SSF were compared. The patients were divided into two groups according to whether the heart rate was greater than 65 beats / min, including 26 cases in group A with heart rate ≤65 beats / min, and 59 cases in group B with heart rate> 65 beats / min. Coronary artery images were processed by coronary artery tracking and freezing technique. The arterial axis cross sections of the left anterior descending coronary artery, the left circumflex artery and the right coronary artery before and after SSF were measured, and the SD values of motion artifact and adjacent fat were calculated. Artifact index (MAI) values; and blind physique by two senior physicians on the image quality score of five points, the score comparison and quantitative analysis. Results The mean heart rate (58.5 ± 5.69) / min in group A was significantly lower than that in non-SSF (24.10 ± 8.62) using MAF SSF (12.65 ± 5.96) (P <0.05). Subjective image score: SSF was used as SSF (4.15 ± 0.45), higher than None-SSF (3.00 ± 1.04), the difference was statistically significant (P <0.05). The average heart rate of patients in group B was 77.73 ± 9.67 times / min. The MAI was significantly lower in patients with SSF (18.09 ± 9.00) and lower than that of None-SSF (66.99 ± 17.49) (P <0.01) The image score using SSF was (3.82 ± 0.78), higher than None-SSF (1.96 ± 0.67), the difference was statistically significant (P <0.01). After treatment with SSF, the MAI in group A decreased by 48% on average, and in group B, the mean MAI decreased by 73% after SSF treatment, which was significantly lower than that in group A. Conclusions Coronary artery tracking and freezing technique (SSF) can improve the image quality of coronary CTA. The effect is more obvious when the patient’s heart rate exceeds 65 beats / min.