Wang Yi-ning, Jin Zheng-yu, Kong Ling-yan, Zhang Zhu-hua, Song Lan, Zhang Shu-yang, Zhang Li-ren, Lin Song-bai, Wang Yun, Zhao Wen-min
Department of Radiology, PUMC Hospital, CAMS and PUMC, Beijing 100730, China.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao. 2006 Feb;28(1):26-31.
To compare the image quality and visibility of arteries of 64-slice spiral coronary CT angiography (CTA) with those of 16-slice spiral coronary CTA, and to evaluate the diagnostic accuracy of 64-slice spiral CT for the assessment of coronary artery stenosis.
Totally 100 patients (Group A) with suspected coronary artery diseases (CAD) were examined by 64-slice spiral CT, 48 of whom also underwent conventional coronary angiography (CAG). Another 100 patients (Group B) with suspected CAD were studied by 16-slice spiral CT. Patients with a heart rate above 70 bpm received oral beta-blockers before the scan. Data were retrospectively analyzed and reviewed by two observers. Image quality was assessed by using a 3-point grading scale from excellent (1) to non-assessable (3) and the rate of displayed coronary branches was calculated. The left main artery (LM), left anterior descending artery (LAD), circumflex artery (CX), and right coronary artery (RCA) were screened for the presence of over 50% stenosis.
The mean heart rates of two groups showed no significant difference [(61 +/- 8) bpm vs. (61 +/- 7) bpm, P > 0.05]. The mean scan time of Group A was significantly shorter than that of Group B [(11.9 +/- 0.9) s vs. (22.2 +/- 1.1) s, P < 0.01]. In the evaluation of image quality, better results were obtained in Group A than in Group B (1.20 +/- 0.47 vs. 1.37 +/- 0. 63, P < 0.05). The visibility of proximal arteries was similar between two groups, while the visibility of some distal arteries and small branches was found higher in Group A than in Group B (LAD distal 92% vs. 48%, CX distal 98% vs. 89%, the first obtuse marginal (OMI) 93% vs. 84%, cone branch (CB) 86% vs. 71%, P < 0.05). Compared with CAG, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 64-slice spiral coronary CTA to identify over 50% stenosis were 94.9% (56/59), 93.2% (124/133), 86.2% (56/65), and 97.6% (124/127), respectively.
With higher temporal and spatial resolution, 64-slice spiral CT provides improved image quality and visibility of small branches as compared with 16-slice spiral CT. 64-slice spiral coronary CTA allows reliable non-invasive diagnosis of obvious coronary artery stenosis.
比较64层螺旋冠状动脉CT血管造影（CTA）与16层螺旋冠状动脉CTA的图像质量及动脉显示情况，并评估64层螺旋CT对冠状动脉狭窄的诊断准确性。
对100例疑似冠心病（CAD）患者（A组）行64层螺旋CT检查，其中48例同时接受了传统冠状动脉造影（CAG）。另100例疑似CAD患者（B组）行16层螺旋CT检查。心率高于70次/分的患者在扫描前口服β受体阻滞剂。数据由两名观察者进行回顾性分析。图像质量采用3分制分级评估，从优（1分）到不可评估（3分），并计算冠状动脉分支显示率。筛查左主干（LM）、左前降支（LAD）、回旋支（CX）和右冠状动脉（RCA）是否存在超过50%的狭窄。
两组患者的平均心率无显著差异[（61±8）次/分 vs.（61±7）次/分，P>0.05]。A组的平均扫描时间显著短于B组[（11.9±0.9）秒 vs.（22.2±1.1）秒，P<0.01]。在图像质量评估中，A组的结果优于B组（1.20±0.47 vs.1.37±0.63，P<0.05）。两组近端动脉的显示情况相似，而A组一些远端动脉和小分支的显示率高于B组（LAD远端92% vs.48%，CX远端98% vs.89%，第一钝缘支（OMI）93% vs.84%，圆锥支（CB）86% vs.71%，P<0.05）。与CAG相比，64层螺旋冠状动脉CTA识别超过50%狭窄的敏感性、特异性、阳性预测值（PPV）和阴性预测值（NPV）分别为94.9%（56/59）、93.2%（124/133）、86.2%（56/65）和97.6%（124/127）。
与16层螺旋CT相比，64层螺旋CT具有更高的时间和空间分辨率，图像质量更好，小分支显示更清晰。64层螺旋冠状动脉CTA能够可靠地对明显的冠状动脉狭窄进行无创诊断。
