Department of Radiology, Affiliated Beijing Tiantan Hospital, Capital Medical University, Beijing 100050, China.
Chin Med J (Engl). 2011 May;124(10):1465-9.
Wall shear stress is an important factor in the destabilization of atherosclerotic plaques. The purpose of this study was to assess the distribution of wall shear stress in advanced carotid plaques using high resolution magnetic resonance imaging and computational fluid dynamics.
Eight diseased internal carotid arteries in seven patients were evaluated. High resolution magnetic resonance imaging was used to visualize the plaque structures, and the mechanic stress in the plaque was obtained by combining vascular imaging post-processing with computational fluid dynamics.
Wall shear stresses in the plaques in all cases were higher than those in control group. Maximal shear stresses in the plaques were observed at the top of plaque hills, as well as the shoulders of the plaques. Among them, the maximal shear stress in the ruptured plaque was observed in the rupture location in three cases and at the shoulder of fibrous cap in two cases. The maximal shear stress was also seen at the region of calcification, in thrombus region and in the thickest region of plaque in the other three cases, respectively.
Determination of maximal shear stress at the plaque may be useful for predicting the rupture location of the plaque and may play an important role in assessing plaque vulnerability.
壁面切应力是导致动脉粥样硬化斑块不稳定的一个重要因素。本研究旨在应用高分辨率磁共振成像和计算流体动力学技术评估颈动脉粥样硬化斑块中壁面切应力的分布。
对 7 例患者的 8 处病变颈内动脉进行评估。高分辨率磁共振成像用于显示斑块结构，通过血管成像后处理与计算流体动力学相结合，获得斑块中的力学应力。
所有斑块中的壁面切应力均高于对照组。在斑块的山顶以及斑块肩部观察到斑块中的最大壁面切应力。其中，3 例在破裂斑块的破裂部位观察到最大壁面切应力，2 例在纤维帽肩部观察到最大壁面切应力。在其他 3 例中，分别在钙化区、血栓区和斑块最厚处观察到最大壁面切应力。
确定斑块中的最大壁面切应力可能有助于预测斑块的破裂部位，并可能在评估斑块易损性方面发挥重要作用。
