Hemodynamics in aneurysm blebs with different wall characteristics

作者：Seyedeh Fatemeh Salimi Ashkezari, Fernando Mut, Bong Jae Chung, Alexander Kwong-Tak Yu, Christopher J. Stapleton, Alfred Pokmeng See, Sepideh Amin‐Hanjani, Fady T. Charbel, Behnam Rezai Jahromi, Mika R. Niemela, Juhana Frösén, Spandan Maiti, Anne M. Robertson, Juan Raul Cebral · 发表于：Journal of NeuroInterventional Surgery · 年份：2020 · DOI：10.1136/neurintsurg-2020-016601 · 被引用次数：43 · 研究领域：Intracranial Aneurysms: Treatment and Complications、Aortic aneurysm repair treatments、Vascular Malformations Diagnosis and Treatment

BACKGROUND: Blebs are important secondary structures of intracranial aneurysms associated with increased rupture risk and can affect local wall stress and hemodynamics. Mechanisms of bleb development and evolution are not clearly understood. We investigate the relationship between blebs with different wall characteristics and local hemodynamics and rupture sites. METHODS: Blebs with different wall appearances in intra-operative videos were analyzed with image-based computational fluid dynamics. Thin red blebs were compared against thick atherosclerotic/hyperplastic white/yellow blebs. Rupture points were identified in videos of ruptured aneurysms harboring blebs. RESULTS: Thin blebs tended to be closer to the inflow than atherosclerotic blebs of the same aneurysm (P=0.0234). Blebs near the inflow had higher velocity (P=0.0213), vorticity (P=0.0057), shear strain rate (P=0.0084), wall shear stress (WSS) (P=0.0085), and WSS gradient (P=0.0151) than blebs far from the inflow. In a subset of 12 ruptured aneurysms harboring blebs, rupture points were associated with thin blebs in 42% of aneurysms, atherosclerotic blebs in 25%, and were away from blebs in the remaining 33%. CONCLUSIONS: Not all blebs are equal; some have thin translucent walls while others have thick atherosclerotic walls. Thin blebs tend to be located closer to the inflow than atherosclerotic blebs. Blebs near the inflow are exposed to stronger flows with higher and spatially variable WSS than blebs far from the i...