目的:对于一些巨大的颅内动脉瘤(GIA),常规的夹闭和血管内治疗是很难应用的。有时颅外至颅内(EC-IC)旁路成为可选的选择。然而,并非所有GIA患者都能从中受益。本研究旨在认识潜在的问题。
方法:我们纳入了符合条件的患者。然后,我们从三个层面进行了研究:临床数据的回顾性回顾,来自两个代表性的患者特定模型的流体结构分析,以及理想化模型的流体-结构相互作用分析,以研究血液动力学和生物力学机制。
结果:在本文中,我们报告了9例接受EC-IC手术的GIA患者.其中,三个人经历了危险的术后出血,一名患者死亡。在这三个病人中,两个缺乏大脑前动脉(ACA)的A1段。数值模拟表明,手术后,对于动脉瘤未破裂且存在ACA的患者,墙体变形,壁应力,压力,振荡剪切指数(OSI)>0.2的面积减少了43%,39%,33%,13%,而没有A1段的患者术后出血占36%,45%,13%,增加了55%,分别。因此,在这种情况下,我们假定了危险的“残端现象”,并从具有不同大小的ACA的理想化模型中进一步证明了这一点。最后,我们发现较大的吻合角度和较小的移植物直径可以减轻这种影响。
结论:神经外科医生在做出临床决定时,应谨慎评估ACAA1段发育不全患者的机会和风险。
OBJECTIVE: Conventional clipping and endovascular treatment are difficult to apply for some giant intracranial aneurysms (GIAs), and sometimes extracranial-to-intracranial (EC-IC) bypass becomes the optional choice. However, not all GIA patients can benefit from it. This study aims to recognize the underlying problems.
METHODS: We included eligible patients in our care. Then, we researched from three levels: a retrospective review of clinical data, fluid-structural analysis from two representative patient-specific models, and fluid-structural interaction analysis for idealized models to investigate the hemodynamic and biomechanical mechanisms.
RESULTS: In this article, we report nine patients with GIA who underwent EC-IC surgery. Of them, three experienced dangerous postoperative hemorrhage, and one patient died. Among these three patients, two lacked the A1 segment of the anterior cerebral artery (ACA). The numerical simulation showed that after surgery, for the patient with an unruptured aneurysm and existence of ACA, the wall deformation, wall stress, pressure, and area of the oscillatory shear index (OSI) > 0.2 were decreased by 43%, 39%, 33%, and 13%, while the patient without A1 segment having postoperative hemorrhage showed 36%, 45%, 13%, and 55% increased, respectively. Thus, we postulated a dangerous \"stump phenomenon\" in such conditions and further demonstrated it from idealized models with different sizes of ACA. Finally, we found a larger anastomosis angle and smaller diameter of the graft can alleviate this effect.
CONCLUSIONS: Neurosurgeon should cautiously evaluate the opportunity and risk for such patients who have aplasia of the A1 segment of ACA when making clinical decisions.