Neurosurgery, Kantonsspital Aarau AG, Aarau, Switzerland
Cerebrovascular Research Group, Department for BioMedical Research, University of Bern, Bern, Switzerland.
J Neurointerv Surg. 2022 Dec;14(12):1258-1263. doi: 10.1136/neurintsurg-2021-018297. Epub 2022 Feb 2.
Unlike clipping that forms an immediate barrier of blood flow into intracranial aneurysms, endovascular treatments rely on thrombus organization and neointima formation. Therefore, a continuous endothelial cell layer is crucial to prevent blood flow in the former aneurysm. This study investigates the origin of endothelial cells in the neointima of endovascular treated aneurysms, specifically whether cells from the parent artery play a role in neointima formation.
In male rats, decellularized and vital side wall aneurysms were treated by coil (n=16) or stent embolization (n=15). The cell tracer CM-Dil dye was injected into the clamped aorta before aneurysm suture to mark initial endothelial cells in the parent artery and enable tracking of their proliferation during follow-up. Aneurysms were analyzed for growth, thrombus formation, and recurrence. Histological evaluation followed with cell counts for specific regions-of-interest.
During follow-up, none of the 31 aneurysms ruptured. Macroscopic residual perfusion was observed in 12/16 rats after coiling and in 1/15 after stenting. Amounts of CM-Dil +cells in coiled versus stented decellularized aneurysms significantly decreased in the thrombus on day 7 (p=0.01) and neointima on day 21 (p=0.04). For vital aneurysms, the number of CM-Dil +cells in the neointima on day 21 showed no significant difference.
Healing patterns were worse in coil-treated than stent-treated aneurysms. Cell migration forming a neointima seemed mainly dependent on the adjacent vessel in decellularized aneurysms, but appeared buoyed by recruitment from aneurysm wall cells in vital aneurysms. Therefore, a cell-rich parent artery might be crucial.
不同于夹闭术直接形成阻止颅内动脉瘤内血流的屏障，血管内治疗依赖于血栓形成和新生内膜形成。因此，连续的内皮细胞层对于防止先前动脉瘤内的血流至关重要。本研究旨在探讨血管内治疗后动脉瘤的新生内膜中内皮细胞的来源，特别是母动脉中的细胞是否在新生内膜形成中发挥作用。
在雄性大鼠中，去细胞化和有活力的侧壁动脉瘤分别接受线圈（n=16）或支架栓塞（n=15）治疗。在缝合动脉瘤前，将细胞示踪剂 CM-Dil 染料注入夹闭的主动脉内，以标记母动脉中最初的内皮细胞，并能够在随访期间追踪其增殖。分析动脉瘤的生长、血栓形成和复发情况。进行组织学评估并对特定的感兴趣区域进行细胞计数。
在随访期间，31 个动脉瘤均未破裂。线圈治疗后 16 只大鼠中的 12 只和支架治疗后 15 只大鼠中的 1 只观察到宏观残余灌注。在第 7 天（p=0.01）和第 21 天（p=0.04）的血栓中，线圈与支架处理的去细胞化动脉瘤中的 CM-Dil+细胞数量明显减少。对于有活力的动脉瘤，第 21 天新生内膜中的 CM-Dil+细胞数量无显著差异。
线圈治疗的动脉瘤比支架治疗的动脉瘤愈合情况更差。在去细胞化动脉瘤中，形成新生内膜的细胞迁移似乎主要依赖于相邻的血管，但在有活力的动脉瘤中，似乎是由动脉瘤壁细胞的募集所推动。因此，富含细胞的母动脉可能至关重要。
