CTA无创功能性评估颈内动脉狭窄

Noninvasive functional assessment of internal carotid artery stenosis using CT angiography

目的探索建立一种基于CTA的无创性评估颈内动脉(ICA)狭窄技术。方法将研究对象CTA断层图像导入Mimics 10.0图像处理软件并重建ICA三维模型,再导入ANSYS 13.0有限元分析软件,赋予边界条件后运算得出评估ICA的功能性指标——虚拟的狭窄段前后压力梯度(TSPG)和血流储备分数(FFR)。结果 DSA检查提示研究对象左侧ICA起始段管腔不规则狭窄约50%,且可见硬化斑块形成。根据本无创性评估技术,成功模拟得出研究对象左侧ICA虚拟TSPG为13.04 mm Hg,虚拟FFR为0.93,提示左侧ICA无功能性狭窄,未达到临床介入治疗标准。结论本研究建立了一种基于CTA的无创性评估ICA狭窄模拟技术,并与临床DSA检查结果一致。

Objective To establish a noninvasive technique, which is based on CT angiography（CTA）, to evaluate the stenosis of internal carotid artery（ICA）. Methods The cross- sectional images of a study subject were imported into Mimics 10 image processing software, and an ICA 3D model was reconstructed. Then, ANSYS 13.0 finite element analysis software was imported, after boundary conditions were defined the functional indicators for assessment of ICA, including virtual trans- stenotic pressure gradient（TSPG） and fractional flow reserve（FFR）, were calculated. Results DSA examination of the study subject showed that the initial segment of left ICA had an irregular stenosis of about 50% with the formation of atherosclerotic plaque. This noninvasive assessment technique successfully simulated the left ICA of the study subject, which revealed that the left ICA virtual TSPG was 13.04 mm Hg, and the virtual FFR was 0.93,indicating that the left ICA had no functional stenosis, which meant that the lesion had not yet developed to the standard that required for clinical treatment. Conclusion In this study, a CTA- based noninvasive assessment virtual technique of ICA stenosis is successfully established, and the results are quite consistent with the clinical DSA findings.