Optimization of Catheter Antennas for Intravascular MR

血管内 MR 导管天线的优化

• 批准号: 6989822
• 负责人: CLAUDIA M HILLENBRAND
• 金额: $ 26.6万
• 依托单位: INTERVENTIONAL IMAGING, INC.
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2007-08-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6989822
• 关键词: bioengineering /biomedical engineering; bioimaging /biomedical imaging; biomedical equipment development; clinical biomedical equipment; computer simulation; diagnostic catheterization; heart catheterization; heart imaging /visualization /scanning; kidney imaging /visualization; magnetic resonance imaging; phantom model; radiowave radiation; swine

DESCRIPTION (provided by applicant): This proposal intends to optimize catheter-based micro radio frequency antennas used in MR-guided, intravascular interventions for high resolution imaging of the arterial wall. A resolution of approximately 200 microns is needed to depict atherosclerotic plaque components in a diseased vessel wall. RF antennas must provide a high signal-to-noise ratio (SNR) to keep acquisition time (TA) short during interventions. Our previous work showed that simple changes in coil winding patterns can double SNR and reduce TA by 4. Thus, we focus on an in-depth optimization of catheter-coils with respect to their SNR. For this purpose, an extensive computer simulation program will be developed which calculates 3D-SNR maps as a function of the antenna geometry and orientation relative to BO. In order to find the best antenna design for a given application, this software will be specifically used to: 1) perform a formal comparison of common intravascular coils (e.g. loop vs. opposed solenoid coil), and 2) investigate possible improvements in SNR by changing geometry through hybrid combination of multiple designs (e.g. by adding loops to an opposed solenoid coil). Design changes necessitate recalculation of the SNR map. When comparing different coils, the best design will be chosen based on the highest SNR calculated at the anticipated location of the wall in a cross-sectional slice through vessel and center of the coil. We will restrict our optimization to coils for coronary and renal artery imaging and construct potentially useful designs identified by simulations using surface mount or micro fabrication technology. All assembled devices will be tested in MR phantom imaging. SNR maps will be acquired at multiple orientations. Measured SNR maps will be compared with simulation data and simulation accuracy for all coils manufactured will be evaluated. Finally, the best designs will be tested in vivo in a porcine animal model. We anticipate that this project will lead to identification and prototyping of SNR-optimized catheter coils for further testing in animal models of vascular disease in Phase II.

描述（由申请人提供）：该提案旨在优化基于导管的微射频天线，用于MR引导，血管内干预措施，用于高分辨率的动脉壁成像。需要大约200微米的分辨率来描绘患病血管壁中的动脉粥样硬化斑块成分。 RF天线必须提供高信噪比（SNR），以在干预期间保持收购时间（TA）。我们以前的工作表明，线圈绕组模式的简单变化可以将SNR倍增并减少4个。因此，我们专注于对导管胶带相对于其SNR的深入优化。为此，将开发一个广泛的计算机仿真程序，该程序计算3D-SNR图作为天线几何形状和相对于BO的方向的函数。为了找到特定应用的最佳天线设计，该软件将专门用于：1）对常见的血管内线圈进行正式比较（例如，循环与相反的螺线管线圈），以及2）2）研究SNR的可能改进，通过将多种设计的混合组合（例如，通过添加对相对的索尔型螺旋体）来改变几何形状。设计变化需要重新计算SNR图。在比较不同的线圈时，将根据在墙壁的预期位置计算的最高SNR选择最佳的设计，该设计在墙壁的预期位置通过线圈的容器和中心选择。我们将优化限制为冠状动脉和肾动脉成像的线圈，并构建使用表面架或微制造技术模拟确定的潜在有用的设计。所有组装的设备将在MR Phantom成像中进行测试。 SNR地图将以多种取向获取。测量的SNR图将与模拟数据进行比较，并评估所有生产线圈的模拟精度。最后，最好的设计将在猪动物模型中在体内进行测试。我们预计该项目将导致对SNR优化导管线圈的鉴定和原型化，以在II期血管疾病的动物模型中进行进一步测试。