Methods for MR Guided Interventions in Coronary Vessels

超出提供的空间。MRI引导下冠状动脉介入治疗的方法MRI可以为评价血管和软组织的形态和功能提供手段。因此，有可能将血管介入性磁共振方法与磁共振诊断方法相结合，以提供单模式综合测试。这一联合测试不仅将诊断疾病，还将指导介入操作并评估干预结果。这种能力可以促进新的治疗方法，并可能导致改善对包括冠状动脉疾病在内的血管疾病患者的管理。该提案的目的首先是开发和实施适用于MR引导的冠状动脉介入治疗的MRI技术，其次是评估在冠状动脉中实施MR引导介入治疗的可行性。该方法的中心原理是通过冠状动脉内注入MR造影剂来产生血管对比增强。这项提案的目标将通过执行计算机模拟、模体研究和对仪表犬的活体研究来实现。我们将追求四个具体目标。(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、近乎实时的冠状动脉多层成像，其基础是冠状动脉内注入磁共振造影剂的对比剂增强血管、下方组织的饱和度以及通过抑制外体积缩小视野。(B)建立适用于同一过程中多次动态冠状动脉MR血管成像的低剂量MR造影剂冠状动脉内注射方案，即浓度、输注量和输注时间。(C)开发被动可视化方法以成像并区分充填造影剂的介入性导管和增强造影剂的冠状动脉，以指导MRI冠状动脉内操作。为此，将研究双腔和双同轴的经皮冠状动脉腔内成形术(PTCA)球囊导管组件。(D)评估在MR引导下对分级狭窄犬模型进行球囊经皮冠状动脉腔内成形术(PTCA)的可行性，以通过对狭窄远端心肌的对比增强首过血流灌注成像来评估介入治疗的结果。表演网站========================================Section End===========================================

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===========================================