1] Toshiba Stroke and Vascular Research Center, University at Buffalo, Clinical and Translational Research Center, Buffalo, New York, USA [2] Department of Biomedical Engineering, Buffalo, New York, USA.
1] Toshiba Stroke and Vascular Research Center, University at Buffalo, Clinical and Translational Research Center, Buffalo, New York, USA [2] Department of Mechanical & Aerospace Engineering, Buffalo, New York, USA.
J Cereb Blood Flow Metab. 2014 Mar;34(3):415-24. doi: 10.1038/jcbfm.2013.209. Epub 2013 Dec 11.
Carotid occlusions are associated with de novo intracranial aneurysm formation in clinical case reports, but this phenomenon is not widely studied. We performed bilateral carotid ligation (n=9) in rabbits to simulate carotid occlusion, and sham surgery (n=3) for control. Upon euthanasia (n=3 at 5 days, n=6 at 6 months post ligation, and n=3 at 5 days after sham operation), vascular corrosion casts of the circle of Willis (CoW) were created. Using scanning electron microscopy, we quantified gross morphologic, macroscopic, and microscopic changes on the endocasts and compared findings with histologic data. At 5 days, CoW arteries of ligated animals increased caliber. The posterior communicating artery (PCom) increased length and tortuosity, and the ophthalmic artery (OA) origin presented preaneurysmal bulges. At 6 months, calibers were unchanged from 5 days, PComs further increased tortuosity while presenting segmental dilations, and the OA origin and basilar terminus presented preaneurysmal bulges. This exploratory study provides evidence that flow increase after carotid occlusion produces both compensatory arterial augmentation and pathologic remodeling such as tortuosity and saccular/fusiform aneurysm. Our findings may have considerable clinical implications, as these lesser-known consequences should be considered when managing patients with carotid artery disease or choosing carotid ligation as a therapeutic option.
在临床病例报告中，颈动脉闭塞与新发性颅内动脉瘤形成有关，但这种现象尚未得到广泛研究。我们通过双侧颈动脉结扎（n=9）来模拟颈动脉闭塞，并进行假手术（n=3）作为对照。在安乐死时（n=3 例在结扎后 5 天，n=6 例在结扎后 6 个月，n=3 例在假手术后 5 天），制作Willis 环（CoW）的血管腐蚀铸型。使用扫描电子显微镜，我们对内膜的大体形态、宏观和微观变化进行了定量，并将发现与组织学数据进行了比较。在 5 天时，结扎动物的 CoW 动脉口径增大。后交通动脉（PCom）长度和迂曲度增加，眼动脉（OA）起源处出现前动脉瘤样膨出。在 6 个月时，CoW 动脉的口径与结扎后 5 天相比没有变化，PComs 的迂曲度进一步增加，同时出现节段性扩张，OA 起源和基底动脉末端出现前动脉瘤样膨出。这项探索性研究提供了证据，表明颈动脉闭塞后血流增加会导致代偿性动脉增粗和病理性重塑，如迂曲和囊状/梭形动脉瘤。我们的发现可能具有重要的临床意义，因为在处理颈动脉疾病患者或选择颈动脉结扎作为治疗选择时，应该考虑到这些鲜为人知的后果。
