16层螺旋CT颈动脉成像:智能触发阈值的合理选择  

16 MDCT Angiography of Carotid Arteries:Comparison of Different Automatic Bolus Tracking Thresholds

作　　者：缪熙音[1] 周建军[1] 陈刚[1] 刘豪[1] 陆海峰[1] 曾良斌[1] 顾君英[1] 张晓骅[1] 曾蒙苏[1] 

机构地区：[1]复旦大学附属中山医院放射科上海市影像医学研究所,上海200032

出　　处：《放射学实践》2007年第9期922-925,共4页Radiologic Practice

摘　　要：目的:研究不同智能触发监测点阈值条件下的CTA扫描效果,以期提高颈动脉CTA图像质量。方法:60例病例随机分为3组进行检查。3组监测阈值分别为80HU、100HU、120HU,监测点选在主动脉弓降部,比较3组双侧颈总动脉、颈静脉胸廓入口处(A点),入口处与分叉处之中点处(B点),颈总动脉分叉处(C点)以及颈静脉孔处(D点)的动静脉强化CT值。结果:在3种监测阈值下,各点的颈动脉强化CT值分别是:A点287.75～316.70,B点338.35～359.30,C点334.70～357.65,D点316.55～320.40,无统计学差异(P>0.05)。各点的颈静脉强化CT值分别是:A点68.10～104.15,B点100.60～169.60,C点120.10～216.70,D点176.10～247.30,而B、C、D点颈静脉强化CT值显示,监测阈值越低,静脉强化CT值越小。监测阈值为80HU时的静脉强化显影明显低于100、120HU两组,有统计学差异(P<0.05)。结论:对于16层螺旋CT而言,以主动脉弓降部为监测点,监测阈值为80HU时,可获得更为理想的颈动脉CTA图象。Objective：To compare the quality of the images using different thresholds of automatic bolus tracking in multi-row detector CT angiography （MDCTA） of carotid arteries. Methods：Sixty patients undergoing MDCTA were randomly allocated to three groups. The automatic bolus tracking thresholds of 80HU, 100HU and 120HU in the descending aorta was used for three groups, respectively. The location of CT value measurements in carotid artery and vein was recorded as follows：the level of proximal common carotid artery （A） ,carotid bifurcation （C） ,jugular foramen （D）, and the midpoint between A and C （B）. Results： Using three different thresholds, the CT attenuation of carotid artery in the four regions were A 287.75-316.70, B 38.35- 359.30, C 334.70-357.65, D 316.55- 320.40 retrospective, there were no statistical difference （P〉0.05）. The CT attenuation of carotid vein in the four regions were A 68.10-104.15 ,B 100.60-169.60,C 120.10-216.70,D 176.10-247.30. However, the CT values of carotid vein in B,C and D regions tended to be lower with lower tracking threshold. The degree of vein enhancement in the group of 80HU were significantly lower than that of 100 H U and 120 H U, and has statistical difference （P〈0.05）. Conclusion： For MDCTA of carotid arteries, the bolus tracking threshold of 80HU in the descending aorta is preferable.

关 键 词：颈动脉 体层摄影术 X线计算机 阈值 

分 类 号：R816.1[医药卫生—放射医学]