三种不同高压注射增强方式对CT图像质量的影响

目的:探讨高压注射器三种不同的增强方式对图像质量的影响。方法:搜集150例病例均使用Lightspeed 16层螺旋CT和Medrad的Stellant D型高压注射器。注射流率4.0ml/s,注射总量80ml,分为甲、乙、丙三组行增强扫描。甲组50例,只使用单管注射,不注射生理盐水冲洗;乙组50例,随即注射生理盐水冲洗;丙组50例使用A筒对比剂和B筒生理盐水按A筒60%B筒40%的比例通过三腔连接管同步注射。评价方式:采用双盲观片法。结果:甲组有伪影40例,占80%,无伪影例数是10例,占20%;乙组有伪影26例,占52%,无伪影24例,占48%;丙组有伪影23例,占46%,无伪影是27例,占54%(P<0.05)。结论:双筒高压注射器以A筒60%B筒40%成比例同步注射时,干扰主动脉内部结构观察的上腔静脉高密度伪影较采用单筒高压注射方法少,与双筒前后注射方法无明显差别。

Comparative Study of Three Methods of High Pressure Injector in CT Contrast Enhancement Image Quality

Objective:To study the influence of three different injection methods on the CT enhancement image quality.Methods:150 patients underwent Lightspeed 16 spiral CT contrast enhancement using Stellant D type power injector (Medrad).The injection rate was 4.0ml/s,and total amount of contrast medium was 80ml.The 150 patients were divided in 3 groups.In group A,only contrast medium was injected without saline flush.In group B,injection of contrast medium was followed by saline flush.In group C,the contrast medium and saline were injected simultaneously with the amount of contrast medium 60% to amount of saline 40%.The image quality was evaluated in a double blinded manner.Results:In group A,image artifacts were observed in 40 cases (80%),in group B,artifacts were observed in 26 cases (52%),and in group C,artifacts were present in 23 cases (46%) (P<0.05).Conclusion:The simultaneous injection of contrast medium and saline flush with the amount of contrast medium 60% to amount of saline 40% produce less artifact than the injection of contrast medium without saline flush.There is no significant difference between the simultaneous injection and the injection of contrast medium followed by saline flush.