运用CTA影像定量评价冠脉重构及斑块发展

目的目前运用CT血管造影(computed tomography angiography,CTA)对冠脉斑块的定量评估多采用自动分析软件,进行由于CTA影像存在斑块伪影极易导致测量不准确,且多数研究只分析冠脉局部病变部位的即时斑块情况,本文将采用手动测量方法,追踪研究整支右侧冠状动脉(right coronary artery,RCA)的斑块发展。方法选择RCA无支架植入、随访时间约12个月的急性冠脉综合征患者12例,获取患者基线和随访时的CTA影像数据,然后利用Osiri X影像处理软件进行整支RCA的弯曲多平面重建,随后按照每隔3mm进行RCA分割和横断面重建,并在一定窗宽和窗口水平条件下进行横断面测量,最后采用类似IVUS分析方法测量获取斑块形态学评价参数,即最小管腔面积、斑块负荷、斑块体积及冠脉重构等,并通过观察这些参数的变化研究整支RCA的动脉粥样硬化斑块的发展。结果对于纳入研究的365段冠脉血管段,在12个月的随访过程中,RCA最小管腔面积减小了0.16 mm2,斑块负荷轻微增加了0.38%,但斑块体积几乎无变化。发生冠脉正性重构占39.2%,负性重构占43.3%,没有重构占17.5%。结论当合理设置窗宽和窗口水平时,运用CTA影像定量评价技术可以纵向评估冠脉斑块的发展。

Quantitative assessment of the coronary plaque progression and arterial remodeling with computed tomography angiography

Objective Quantitative assessment of coronary plaque by computed tomography angiography ( CTA)is usually acquired by automatic analysis software,which causes inaccuracy in measurement due to CTA artifact. And most studies commonly investigate the immediate local lesion of the coronary plaques. We use the manual measurement method and trace the development of plaques along the entire right coronary artery ( RCA)in this paper. Methods Twelve patients with acute coronary syndrome who have not been stented in RCA at baseline CTA and followed-up for about 12 months were selected. First we used the image processing software OsiriX and processed the CTA image data. Then we acquired the curved multiplanar reformatted ( CMPR)rendering of entire RCA at baseline and followed up. Followed by dividing the RCA into consequent segments with 3mm long,we acquired the cross-sectional reconstruction and drew the plaque morphology of each segment in a reference window width and window level condition. Finally we utilized the IVUS-like analysis method to obtaln the paramaters,including the minimum lumen area,plaque burden,plaque volume and coronary reconstruction, and evaluate the atherosclerotic plaque development of entire RCA by the changes from baseline to follow-up. Results Total of the 365 segments of RCA were included in this study. Compared with the baseline,the minimum lumen area of RCA at 12-month follow-up reduced 0 . 16 mm2 ,the plaque burden increased slightly by 0 . 38%,however the plaque volume almost did not change. The positive remodeling of RCA accounted for 39. 2%,negative remodeling for 43. 3%, and absence of remodeling for 17 . 5%. Conclusions A quantitative evaluation of the coronary plaque development is avallable when setting up the reasonable window width and window level.