Methods for MR Guided Interventions in Coronary Vessels

超出所提供的空间。MRI可以提供评估血管和软组织形态和功能的手段。因此，可以将血管介入MR方法与MR诊断方法相结合，提供单一模式的综合检测。这种综合测试不仅可以诊断疾病，还可以指导干预程序并评估干预结果。这种能力可以促进新的治疗方法，并可能改善对血管疾病（包括冠状动脉疾病）患者的管理。本提案的目的是首先，开发和实施适用于核磁共振引导冠状动脉介入治疗的MRI技术，其次，评估在冠状动脉中进行核磁共振引导介入治疗的可行性。该方法的核心原理是通过冠状动脉内注入MR造影剂来增强血管造影剂。本提案的目标将通过对仪器狗进行计算机模拟、模拟研究和体内研究来解决。我们将努力实现四个具体目标。(a)开发和优化磁共振技术，包括脉冲序列和射频线圈，用于动态近实时的冠状动脉多层成像，基于冠状动脉内注入磁共振造影剂的对比增强血管，饱和底层组织和减少视野与外部体积抑制。(b)建立低剂量磁共振造影剂冠状动脉内输注方案，即输注浓度、输注量和输注时间，适用于同一过程中多次动态冠状动脉磁共振血管造影。(c)发展被动的可视化方法，以成像和区分造影剂填充的介入导管与造影剂增强的冠状血管，以指导冠状动脉内MRI手术。双腔和双同轴经皮腔内冠状动脉成形术（PTCA）球囊导管组件将为此目的进行研究。(d)评估mri引导球囊PTCA对犬分级狭窄模型的可行性，通过对狭窄远端心肌进行增强第一次灌注成像，评估干预结果。网站性能 ======================================== 节结束 ===========================================

EXCEED THE SPACE PROVIDED. Methods for MRI Guided Interventions in Coronary Vessels MRI can provide the means to assess both vascular and soft tissue morphology and function. For this reason, it is possible to combine vascular interventional MR methods with MR diagnostic methods to provide a single-modality comprehensive test. This combined test would not only diagnose disease, but would also guide interventional procedures and assess the results of intervention. Such capabilities could facilitate new therapeutic approaches and may result in improved management of patients with vascular disease, including coronary artery disease. The objectives of this proposal are first, to develop and implement MRI techniques suitable for MR-guided coronary interventions, and second, to assess the feasibility of performing MR-guided interventions in the coronary arteries. The central principle of the proposed approach is the generation of vascular contrast enhancement by intracoronary infusion of MR contrast agent. The objectives of this proposal will be addressed by performing computer simulations, phantom studies and in vivo studies on instrumented canines. We will pursue four specific aims. (a) Develop and optimize MR techniques, that include pulse sequences and RF coils, for dynamic near-real time multislice imaging of the coronary arteries, based on contrast-enhanced vessel by intracoronary infusion of MR contrast agent, saturation of the underlying tissue and reduction of the field-of-view with outer volume suppression. (b) Establish low-dose MR contrast agent intracoronary infusion protocols, i.e. concentration, volume, and duration of infusion, suitable for multiple dynamic coronary MR- angiography sessions during the same procedure. (c) Develop passive visualization approaches to image and differentiate contrast agent-filled interventional catheters from contrast enhanced coronary vessels, for guiding intracoronary procedures with MRI. Dual lumen and dual-coaxial percutaneous transluminal coronary angioplasty (PTCA) balloon catheter assemblies will be investigated for that purpose. (d)Assess the feasibility of performing MR-guided balloon PTCA on a canine model of graded generated stenosis to assess the results of the intervention via contrast-enhanced first pass perfusion imaging of the myocardium distal to the stenosis. PERFORMANCE SITE ========================================Section End===========================================