| Part one The influencing factor for the coronary imaging technique and image quality of 64-section MSCTObjective: To approach the chief factor for coronary artery imaging in 64-section MSCTA, summarize the skill and experience to gain the best image. Methods: A total of 78 patients who was clinical diagnosed or suspicious patients of coronary atherosclerotic heart disease underwent 64-MSCTA. The age, gender, the average heart rate of scan , the variation of heart rate and coronary artery calcification index were calculated. The coronary artery diameter was measured in cross section reconstruction image, the CT value of aortic root in arterial phase was also calculated. The image quality were divided into four groups according to the image score, to evaluate the coronary segments whose diameters exceed 2mm. Analyzing the influence of heart rate, reconstruction phase window, the density and noise of contrast medium in coronary artery, coronary artery calcification and respiratory movement on picture quality.Results: There were 999 coronary segments which can be assessed for their diameters exceed 2mm, all of these, 1 grade image quality are 739 segments, 2 grade image quality are 123 segments, 3 grade image quality are 120 segments, and 17 coronary segments could not be assessed due to poor image quality. Among the patients whose heart rate 60 heat per min, 1 and 2 grade image quality occupy 93.4%, among the group of patients whose heart rate between 60 to 70 heat per min, 1 and 2 grade image quality occupy 87.2%, among the group of patients whose heart rate exceed 70 heat per min, 1 and 2 grade image quality occupy 61.1%, which has statistical significance byχ2 check-up. The image quality obtain best in 75%R-R phase window in 727 segments which accounts 72.8%, while in 45%R-R phase window in 213 segments.Conclusion:Heart rate,cardiac rhythm and coronary artery calcification accounts the key point for image quality. To apply retrospective electrocardio-gating technology, different reconstruction phase window and also to control heart rate well is the key point for image quality.Part two The correlation research of 64-section MSCTA coronary remodeling and the stability of atheromatous plaqueObjective: To investigate the coronary remodeling in 64-section MSCTA, analyze the correlation between coronary remodeling and acute coronary artery syndrome, stable angina, calcification index and CT value of plaque, to evaluate the role of coronary remodeling in judging the stability of plaque.Methods: 76 patients who were diagnosed as of having CAD clinically had undergone 64-MSCT angiography. They were divided into two groups according to clinical materials: ACS and SA. The reconstitution index of coronary artery, calcification index were obtained. Compare the reconstitution index of coronary artery between ACS and SA, between different calcification index.Results: The rate of positive remodeling in ACS group was 58.1%, while this rate is 24.7% in SA group which demonstrated significant difference between the two groups. The calcification index of coronary artery between ACS and SA has significant difference. The calcification index of coronary artery grow as the age increase in two groups, the calcification index of SA obviously exceed ACS in the same year group. With the calcification index of coronary artery increases, the rate of positive remodeling cuts down. Conclusion:Coronary remodeling has a great correlation with CAD in the process of coronary atherosclerosis. 64-section MSCT not only can evaluate the component of plaque but also can predict the risk of acute coronary artery in the crowd of having coronary risk factor or coronary artery disease by analyzing the plaque and the type of coronary remodeling. |
PDF Full Text Request