METHODS: We retrospectively evaluated consecutive patients who underwent endovascular thrombectomy for acute ICAO. Contrast filling of the extracranial ICA in preprocedural CTA was considered apparent ICAO. Non-contrast filling of the extracranial ICA was evaluated according to the contrast-filled lumen configuration, lumen margin and location, Hounsfield units of the non-attenuating segment, and presence of calcification or an intimal flap. Digital subtraction angiography findings were the reference standard for ICAO etiology and the occlusion site. A diagnostic tree was derived using significant variables according to pseudo-occlusion, atherosclerotic vascular disease (ASVD), thrombotic occlusion, and dissection.
RESULTS: A total of 114 patients showed apparent ICAO (n = 21), pseudo-occlusion (n = 51), ASVD (n = 27), thrombotic occlusion (n = 9), or dissection (n = 6). Most pseudo-occlusions (50/51, 98.0%) showed dependent locations with ill-defined contrast column margins and classic flame or beak shapes. The most common occlusion site of pseudo-occlusion was the petro-cavernous ICA (n = 32, 62.7%). Apparent ICAO mainly appeared in cases with occlusion distal to the posterior communicating artery orifice. ASVD showed beak or blunt shapes in the presence of low-density plaques or dense calcifications. Dissection revealed flame- or beak-shaped appearances with circumscribed margins. Thrombotic occlusions tended to appear blunt-shaped. The decision-tree model showed a 92.5% overall accuracy.
CONCLUSIONS: CTA characteristics may help diagnose ICAO etiology. We provide a simple and easy decision-making model to inform endovascular thrombectomy.
方法:我们回顾性评估了因急性ICAO行血管内血栓切除术的连续患者。术前CTA中颅外ICA的对比填充被认为是明显的ICAO。根据造影剂填充管腔构型评估颅外ICA的非造影剂填充。管腔边缘和位置,非衰减段的亨氏单位,和钙化或内膜瓣的存在。数字减影血管造影结果是ICAO病因和闭塞部位的参考标准。根据伪遮挡,使用显著变量得出诊断树,动脉粥样硬化性血管疾病(ASVD),血栓性闭塞,和解剖。
结果:共有114例患者表现出明显的ICAO(n=21),伪遮挡(n=51),ASVD(n=27),血栓性闭塞(n=9),或解剖(n=6)。大多数假性闭塞(50/51,98.0%)显示出依赖位置,对比柱边距不明确,经典的火焰或喙形状。假性闭塞最常见的闭塞部位是海绵样ICA(n=32,62.7%)。表观ICAO主要出现在后交通动脉口远端闭塞的病例中。在存在低密度斑块或致密钙化的情况下,ASVD显示喙或钝形。解剖显示火焰状或喙状外观,边缘有限。血栓闭塞倾向于呈钝形。决策树模型显示出92.5%的总体准确率。
结论:CTA特征可能有助于诊断ICAO病因。我们提供了一个简单易行的决策模型来告知血管内血栓切除术。