冠状动脉多层螺旋CT成像技术及临床应用研究

【作者】 吴春根；

【导师】 周康荣；

【作者基本信息】 复旦大学 ， 影像医学与核医学， 2003， 博士

【摘要】 第一部分 多层螺旋CT冠状动脉血管成像技术研究目的：探讨MSCT冠状动脉血管成像技术的影响因素。材料与方法：85例病人通过MSCT扫描，采用回顾性心电门控方法重建冠状动脉图像，根据螺距分为0.375、0.5和0.625三部分，每部分按心率分为四组，即≦60次/分、61～70次/分、71～80次/分、﹥80次/分。由两名放射科医师评估重建图像，根据图像质量评分。比较不同心率组以及不同螺距组各组之间的差异。结果：在心率≦60次/分组和61～70次/分组，两组图象质量差异无显著性（P>0.05）；在心率为71～80次/分与心率>80次/分组，两者差异无统计学意义（P>0.05）；而在相对低心率组（≦60次/分、61～70次/分）与相对高心率组（71～80次/分、≧80次/分）间，两者差异有统计学意义（P<0.05）。在不同螺距组中，小螺距组比大螺距组图像质量高，螺距为0.375组图像质量最高，螺距为0.5组高于0.625组。在R-R间期重建图像，40%～80%期间图像伪影明显比其他期间少。重建方式中VR和CPR图像明显比MIP图像质量好。结论：多层螺旋CT冠状动脉血管成像中心脏的搏动伪影是影响冠状动脉重建图像质量的重要因素。心率越低越有助于冠状动脉显影。其次小螺距扫描因减少伪影有助于改善冠状动脉图像质量。关键词 体层摄影术，X线计算机；冠状血管造影术第二部分 冠状动脉病变多层螺旋CT与选择性冠状动脉造影对照研究目的：探讨MSCT检测冠状动脉病变的临床应用价值。材料与方法：共计50例拟诊冠心病的住院病人均作了MSCT和选择性冠状动脉造影。间隔1～3天。所有病人均为窦性心律。MSCT采用4×1mm准直宽度、500ms/周旋转速度和0.375～0.625螺距的扫描方案。用回顾性心电门控重建冠脉图像。首先盲法评价冠状动脉MSCT图像质量和MSCT所显示的冠脉病变。将MSCT检查结果与选择性冠脉造影对照研究。结果：450段冠脉中381段（85%）可用于诊断。共计69段冠脉不同程度狭窄，MSCT检出60段（87%）。21段轻度狭窄中的16段（76%）MSCT检出。8段中度狭窄MSCT检出7段（86%）。重度狭窄和次全狭窄检出率分别为83%(15/18)和93%(14/15)。7段完全闭塞MSCT全部检出（100%）。MSCT判断冠脉狭窄的敏感性为87%、特异性89%、准确性89%、阳性预测值65%、阴性预测值<WP=5>97%。MSCT检查出4例冠脉开口异常；MSCT检出37段冠脉钙化，而冠脉造影只显示13段。MSCT诊断冠脉狭窄除了直接征象外，狭窄前冠脉分支代偿性扩张、狭窄后冠脉造影剂充盈不良、狭窄冠脉供血区心肌灌注不良、狭窄冠脉供血区心肌梗死以及大块钙化斑块等征象有助于冠脉狭窄的诊断。另外，50例心绞痛病人中MSCT检出5例（10%）肺栓塞。结论：虽然MSCT诊断冠状动脉狭窄一定程度受心脏搏动伪影的影响，但诊断低心率病人的冠脉狭窄仍具有较高的准确性。同时MSCT可以检出冠脉造影一些难以显示的病变，包括冠脉钙化和冠脉开口异常。更多还原

【Abstract】 PART ONETechnical study of coronary angiography with multislice helical computed tomography Objective: to investigate the factors that could influence the quality of coronary angiography with multislice helical computed tomography(MSCT). Methods: A total of 85 consecutive patients were studied by MSCT. The coronary axial images were reconstructed by retrospective ECG-gated technique. First of all, the patients were divided into three groups according to the scan pitches which were 0.375,0.5 and 0.625,then each group was divided into four subgroups by the patient heart beat rate, which were ≦60bpm,61～70bpm,71～80bpm and ﹥80bpm respectively. The image qualities of the four groups were evaluated and scored by two radiologists. The scores of all groups were statistically compared with each other. Results: The difference of coronary image qualities was not statistically significant between the ≦60bpm group and 61～70bpm (P>0.05).The same result was also found between 71～80bpm group and ≧80bpm.while the relative lower rate of heart groups(≦60bpm and 61～70bpm) compared with relative higher (71～80bpm and ≧80bpm),the differences of the image quality were statistically significant(P<0.O5). Among the different pitch groups, the image quality of smaller pitch group was better than that of larger one. The image of 0.375 pitch was the best of all. And it was better with 0.5 pitch than 0.625 pitch. The artifacts of the images reconstructed in phases of 40%～80% R-R cycle were less than the other phases. The image reconsctructed with both VR and CPR methods were better than thant with MIP method. Conclusion: The motion artifact due to heartbeat is the most important factor that influences the quality of coronary MSCT image. The lower heartbeat rate, the better is the quality of coronary image. The small pitch scan can improve the quality of the coronary MSCT image by<WP=7>reducing motion artifact. Key words: Tomography,X-ray computed,Coronary angiography更多还原