电子束CT增强容积扫描检测早期实验性心肌缺血的方法及初步结果

目的：探讨电子束ＣＴ增强容积扫描检测早期实验性心肌缺血的方法，并报告初步结果。材料和方法：用Ｉｍａ－ｔｒｏｎＣ－１５０型电子束ＣＴ机对冠状动脉结扎后１．５ｈ的５例实验犬进行心脏的碘造影剂增强容积扫描。仔细观察左心室心肌缺血在电子束ＣＴ图像上的形态学表现，测定并对比分析心肌缺血区和正常区的ＣＴ值及两者与左心室腔ＣＴ值的比值（Ｍ／Ｌ值）。结果：电子束ＣＴ增强容积扫描能清晰地显示心肌低密度缺血区的部位、范围、形态、密度等；缺血区的ＣＴ值及Ｍ／Ｌ值显著低于正常心肌区。结论：电子束ＣＴ可作为检测、分析心肌缺血早期形态学表现和定量分析其ＣＴ值变化的一种高敏感性的非创伤性方法。

The Detection of Experimental Myocardial Ischemia in Early Stage with Enhanced Volume Scans of EBCT: A Report of the Methods and Preliminary Results

Purpose: Reporting the methods and preliminary results of the studies on morphology and quantitative assessment of density of experimental myocardial ischemia in early stage with enhanced volume scans of electron beam computed tomography (EBCT). Materials and methods: At 1 5 hour after ligating the branches of coronary arteries of five dogs, myocardial enhanced volume scans were done by EBCT scanner (Imatron C 150 type) with iodinated contrast medium. The morphologic findings of myocardial ischemia in EBCT images were carefully observed. We measured and compared the CT numbers (Hu) and the ratio of left ventricular myocardial and luminal CT number (M/L values) in the myocardial ischemia and normal areas. Results: The site, extent, shape, density and so on of the myocardial ischemic areas can be shown clearly by EBCT enhanced volume scan. The CT numbers and the M/L values of the myocardial ischemic areas were significantly lower than that of the normal myocardial areas (P<0 002). Conclusion: Evaluating and analysing the morphologic findings of myocardial ischemia in early stage and quantitative assessment its CT value change with EBCT is noninvasive and highly sensitive.