Carotid Intraplaque Hemorrhage: MRI of Therapeutic Response and Clinical Sequelae

摘要 磁共振成像（MRI）是一种经过验证的技术，可以非侵入性地识别关键的病理性 颈动脉粥样硬化的特征。先前的MRI研究表明，颈动脉斑块内出血（IPH） 和管腔表面破坏与未来缺血性事件的风险增加有关，IPH是 与更快的斑块进展和更大的炎症活动的存在相关， 新生血管形成 在我们目前的队列研究中，我们验证了一个假设，即尽管他汀类药物治疗和积极的调节， 血压，IPH的颈动脉病变的稳定性受到损害。迄今为止的调查结果支持我们最初的 假说.此外，初步的中期分析我们的数据表明，潜在的危险因素和MRI信号 与IPH进展相关的特征。然而，长期随访对于 证实了这些有希望的初步发现。 这种竞争性更新的中心假设是：i）血流动力学因素和斑块增加 新生血管形成与新发或复发IPH的发生相关，以及ii）斑块发生率 进展是由反复的IPH驱动的，其特征可以通过MR T1和T2映射来表征，这是一个定量的 评估IPH消退和复发的方法。 我们研究的长期目标是在前瞻性临床研究中利用MRI来深入了解 高危颈动脉斑块的发病机制，以确定与更快进展相关的风险因素， 并最终建立颈动脉斑块成像作为临床诊断工具，以减少中风的发生。 在全球范围内，中风仍然是严重的长期残疾和死亡的主要原因之一， 动脉粥样硬化是一个重要因素。迫切需要更好地了解其发病机制， 开发更有效的一级和二级预防中风的方法。

Abstract Magnetic resonance imaging (MRI) is a proven technique that can non-invasively identify key pathological features of carotid atherosclerosis. Prior MRI studies have shown that carotid intraplaque hemorrhage (IPH) and lumen surface disruption are associated with increased risk for future ischemic events, and that IPH is associated with more rapid plaque progression and presence of greater inflammatory activity and neovascularization. In our current cohort study, we tested the hypothesis that despite statin therapy and aggressive regulation of blood pressure, stability of carotid lesions with IPH is compromised. Findings to date support our original hypothesis. Further, preliminary interim analysis of our data suggest potential risk factors and MRI signal characteristics that are associated with the progression of IPH. However, longer-term follow-up is critical to confirm these promising initial findings. The central hypotheses of this competing renewal are that i) hemodynamic factors and increased plaque neovascularization are associated with the development of new or repeated IPH, and ii) the rate of plaque progression is driven by repeated IPH that can be characterized by MR T1 and T2 mapping -- a quantitative means to assess IPH resolution and recurrence. The long-term goals of our research is to utilize MRI in prospective clinical studies to gain insight into the pathogenesis of the high-risk carotid plaque, to identify risk factors associated with more rapid progression, and ultimately, to establish carotid plaque imaging as a clinical diagnostic tool for reduction of incident stroke. Globally, stroke remains one of the leading causes of serious long-term disability and mortality and carotid atherosclerosis is a significant contributor. A better understanding of its pathogenesis is critically needed to develop more effective methods for primary and secondary stroke prevention.