能谱CT在局部心肌活性检测中的临床应用探讨

Clinical Applied of Dual Energy Spectral CT in the Detection of Regional Myocardial Activity

目的:通过研究评价能谱CT成像的功能参数的有效性,探讨结合心功能评估软件在心肌活性检测方面的临床应用价值,从而为评估心肌活性提供一种新颖可靠的影像学方法。方法:收集我院40例行心功能检查的缺血性心脏病患者,均在一次扫描中行宝石能谱CT高分辨率模式(HD模式)的回顾性心电门控冠脉CTA扫描和宝石能谱成像(GSI模式)。患者均在一周内行心脏MRI扫描。在GSI能谱图像上找出心肌灌注稀疏区。在高分辨率冠脉CTA图像上分析冠状动脉的狭窄程度。将采集的冠脉CTA图像从0%到95%期相,以5%为间隔重建成20个期相,输入AW 4.4工作站心功能分析软件包,自动计算得到左室心功能牛眼图。分别记录GSI能谱图像上心肌灌注稀疏区和灌注正常区,在心功能牛眼图上对应的各节段的平均室壁运动度和室壁增厚率,用独立样本t检验对结果做分析比较,并将评估结果和MRI评估结果做一致性比较。结果:能谱成像图像上找出27个心肌灌注稀疏区,对应心功能牛眼图共126个节段,能谱CT检测出的心肌灌注稀疏区均有区域供血冠脉50%以上狭窄。能谱CT图像上心肌灌注稀疏区与灌注正常区对应心功能牛眼图上的节段平均室壁运动度和室壁增厚率存在显著差异,分别是(3.51±1.54与7.57±1.94,P=0.00)和(26%±8.8%与62%±11.3%,P=0.00)。MRI灌注图像上找出的心肌灌注稀疏区域和灌注正常区域以及其在电影图像上对应的区域室壁运动度和室壁增厚率的结果与CT定量分析结果完全吻合。结论:能谱CT其冠脉CTA扫描结合能谱CT双能量延迟扫描一次扫描,不但可以通过分析冠状动脉血管形态和通过物质分离成像以及其他能谱定量分析参数判断心肌血供情况,提高缺血心肌的检测效率,还可以结合心功能分析软件评估心肌功能的情况,且与MRI电影成像和心肌灌注成像有较高的一致性。

Objective： To study the clinical application value of spectral CT combined with cardiac function assessment software in detecting myocardial activity, so as to provide a novel and reliable imaging diagnostic system for the detection of regional myocardial activity. Methods： 40 patients with coronary heart disease were scanned with the high resolution density coronary CT angiography （HDCTA） and the gemstone spectral imaging （GSI） modes. In addition, all cases had the Cardiac MR/ scan within a week. HDCTA images were used to measure stenoses. Detect the myocardial perfusion sparse areas on the GSI images. HDCTA images were reconstructed into 20 phases, from 0% to 95%, with 5% interval, and then input them into the cardiac fimction analysis software package of AW4.4 workstation, it automatically calculate the bullseye map of left ventricular function. Record the average segmental wall motion and wall thickening of the bullseye map corresponding to the myocardial perfusion sparse areas and normal areas of GSI images, and were performed with two-sample t test. Do the consistency test between CT and MRI evaluation results. Results： Spectral CT have detected 27 regions of myocardial perfusion sparse areas on the GSI images, a total of 126 segments corresponding to the bullseye map. All myocardial perfusion sparse areas of the GSI images had associated coronary artery with more than 50% stenosis of the intravascular diameter. There were significant differences in the average segmental wall motion and wall thickening of the bullseye map corresponding to the myocardial perfusion sparse areas and normal areas of GSI images： （3.51 ± 1.54 and 7.57± 1.94, P = 0.00）, （26% ± 8,8% and 62% ±11.3%, P = 0.00）. The results have high consistency with cardiac cine-MRI imaging and myocardial perfusion imaging. Conclusions： The coronary CTA scan combined with the delayed scan of dual energy spectral imaging in the same scan of Spectral CT, not only can analyze the coronary artery morphology and evaluate the myocardial blood supply, improve the efficiency of the detection of myocardial ischemia, but also can evaluate myocardial function with functional analysis software.