Characterization of intracranial vessel wall morphology and inflammation using 3D high resolution MRI

项目摘要 脑血管疾病是中风的主要来源。然而，临床医生治疗颅内病变的患者 作为潜在的病理生理机制，血管疾病往往处于最有效的治疗方法的困惑之中。 而且可能的进展还不清楚。直到最近，对病理来源-血管-的非侵入性评估 墙-是不可能的。尽管磁共振成像(MRI)技术的进展显示出潜力 对于血管壁成像(VWI)，这些方法的真实性能指标定义很差。真实的 壁成分，特别是炎性成分的分辨率和特征尚未得到 已经确立，并在从业者中有所不同。该项目将实施体内颅内的新方法 VWI采用高场强MRI(3T和7T)。这一目标将通过理论设计和 模拟，体外模型，体内实施，组织学验证。 首先，我们将优化高分辨率(亚0.5 mm各向同性)3D黑血快速自旋回波磁共振成像(简称SPACE 在西门子平台上)3T和7T用于全脑颅内VWI。血管壁信噪比， 锐度，与周围的脑脊液(CSF)或脑实质的对比将被模拟和 最优化。这将在体外模型上得到验证，并通过10名健康志愿者和10名健康志愿者的体内扫描进行验证 患有颅内血管疾病的患者。我们还将实施压缩感知方法，以减少 扫描时间较长(目前约为10分钟)，使其在临床上可行。第二：3D空间， 超短回声时间(UTE)序列和T2*标测/定量磁化率标测(QSM)方法 为了使用超小超顺磁性氧化铁(USPIO)造影剂检测炎症，将 在一系列浓度范围内的USPIO模体中开发和验证。这些方法将得到优化 目的：检测10例有颅内斑块的患者对USPIO的摄取情况，并确定最佳治疗方法。 在预定手术前立即进行的影像检查中对摄取部位的确认 将对10例颅内动脉瘤患者进行组织学检查。第三：3T成像的能力 描述高危血管壁的特征(如斑块内出血、腔内血栓、Gd 增强和USPIO摄取)将与7T扫描对30例患者进行比较 脑血管疾病。 成功的项目实施将提供表征颅内血管高危特征的方法 WALL可用于临床上根据患者的具体情况评估中风的风险，并具有 跨供应商平台进行验证。这些方法可以用来指导针对患者的治疗并改进 中风结果--直接支持国家心肺血液研究所的使命。

Project Summary Cerebrovascular disease is a major source of stroke. However, clinicians treating patients with intracranial vascular disease are often in a quandary as to the most effective treatment as the underlying pathophysiology and likely progression is obscure. Until recently, non-invasive evaluation of the source of pathology - the vessel wall - was not possible. Although advances in Magnetic Resonance Imaging (MRI) technology show potential for vessel wall imaging (VWI), the true performance metrics of these approaches are poorly defined. The true resolution and the characterization of wall components, specifically inflammatory components, have not been established and vary among practitioners. This project will implement new approaches to in vivo intracranial VWI using high field strength MRI (at 3T and 7T). This goal will be achieved with theoretical design and simulations, in vitro models, in vivo implementation, with histology validation. First: we will optimize high-resolution (sub 0.5mm isotropic) 3D black blood fast-spin-echo MRI (termed SPACE on Siemens platforms) at 3T and 7T for whole brain intracranial VWI. The vessel wall signal to noise ratio, sharpness, and contrast to surrounding cerebrospinal fluid (CSF) or brain parenchyma will be simulated and optimized. This will be validated on in vitro models and with in vivo scanning of 10 healthy volunteers and 10 patients with intracranial vascular disease. We will also implement compressed sensing method to reduce the scan time of the long acquisition (currently around 10 minutes) to make it clinically feasible. Second: 3D SPACE, Ultra-short echo time (UTE) sequences and T2* mapping/quantitative susceptibility mapping (QSM) methods for detecting inflammation using Ultra-Small Super-Paramagnetic Iron Oxide (USPIO) contrast agents will be developed and validated in USPIO phantoms with a range of concentrations. These methods will be optimized to detect USPIO uptake in 10 patients with intracranial plaques, and the best approaches will be determined. Confirmation of the location of uptake assessed on imaging performed immediately prior to scheduled surgery will be sought on histology in 10 patients with intracranial aneurysms. Third: The ability of 3T imaging to characterize high-risk vessel wall features (such as intraplaque hemorrhage, intra-luminal thrombus, gadolinium enhancement, and USPIO uptake) will be assessed compared to scanning at 7T on 30 patients with cerebrovascular disease. Successful project conduct will provide methods to characterize the high-risk features of the intracranial vessel wall that could be clinically used to evaluate risk of stroke on a patient-specific basis and with a tool for validation across vendor platforms. These methods could be used to guide patient-specific therapy and improve stroke outcome – directly supporting the mission of the National Heart, Lung, and Blood Institute.