含服硝酸甘油对64层螺旋CT冠状动脉成像质量影响的分析

目的 定量评估64层CT在冠状动脉成像中含服和不含服硝酸甘油对冠状动脉显示的差异.方法 分别在相对时段中对含服硝酸甘油(A组)和不含服硝酸甘油(B组)的各100例患者进行64层CT冠状动脉检查,2组受检者均采用回顾性后门控智能mA扫描技术.分别选取左、右冠状动脉的最佳期相进行MPR、MIP、CPR、VR重组.对2组图像分别进行冠状动脉10个测量点管径的测量,并对右冠状动脉、前降支、回旋支3支冠状动脉显示的分支数目进行统计,然后对2组图像管径测量值和分支数目采用完全随机的两样本均数t检验进行统计学比较.结果 右冠状动脉近、中、远段管径A组比B组分别增加0.29、0.17、0.11mm,扩张率分别为8.0%、5.0%、4.0%;前降支分别增加0.40、0.23、0.10 mm,扩张率分别为11.0%、8.0%、4.7%;回旋支分别增加0.42、0.35、0.12 mm,扩张率分别为13.5%、12.5%、5.5%;左主干增加0.31 mm,扩张率7.8%.A组较B组分支数目增加率,右冠状动脉、前降支、回旋支分别为83%、80%、113%.A、B 2组冠状动脉10个血管节段中,右冠状动脉近段、左主干、前降支近、中段、回旋支近、中段差异有统计学意义(t值分别为3.86、3.74、5.35、3.58、5.29、4.64,P值均＜0.01);右冠状动脉中、远段、前降支远段、回旋支远段差异亦有统计学意义(t值分别为2.13、2.58、2.35、2.14,P值均＜0.05).结论 服用硝酸甘油能有效扩张冠状动脉并能有效增加冠状动脉分支的显示,从而提高64层CT冠状动脉成像质量.

Quantitative evaluation of image quality about taking nitroglycerin on 64-slice spiral coronary angiography

Objective To quantitatively evaluate the influence of taking nitroglycerin on the lumen diameter of coronary arteries and segments visualized on 64-MSCT angiography.Methods Two hundred patients were recruited in this study:half of the patients (group A) received nitroglycerin,the other half (group B) served as the control group and did not receive nitroglycerin.CT anglography was performed using 64-MSCT scanner with ECG modulated mA turned on.MPR,MIP,CPR and VR images in best phase were used to display coronary arteries.Lumen diameters of each coronaries were measured from 10 different slices and number of segments visualized were documented.All the data was analyzed using t test.Results For right coronary artery (RCA),in proximal,middle and distant segments,the lumen diameters in group A increased 0.29,0.17,0.11 mm (8.0% ,5.0% ,4.0%) than group B,respectively. For left anterior descending branch (LAD),the lumen diameters increased 0.40,0.23,0.10 mm(11.0% ,8.0% ,4.7%)respectively.For left circumflex (LCX),the lumen diameters increased 0.42,0.35,0.12 mm(13.5%,12.5% ,5.5%) respectively.For left main artery (LMA),the lumen diameters increased 0.31 mm and the increased percentage was 7.8%.The visualized segments were significantly more in group A than in group B.The percentage of increased number was 83% for RCA,80% for LAD,and 113% for LCX,respectively.In proximal,middle segments of LAD and LCX,together with RCA and LMA,the diameters were statistically different between group A and group B (t=5.35,3.58,5.29,4.64,3.86 and 3.74,P＜0.01).In distant segments of LAD,LCX and RCA,together with middle segments of RCA,there were differences in diameters between group A and group B (t=2.35,2.14,2.58,2.13,P＜ 0.05).Conclusion Using nitroglycerin can significantly improve the image quality by expanding the diameter of coronary arteries and increasing the number of visualized segments in 64-MSCT coronary angiography.