磁共振成像中射频线圈的时域有限差分/有限元混合模拟

Time-domain finite-difference/finite-element hybrid simulations of radio frequency coils in magnetic resonance imaging.

作者信息

Wang Shumin, Duyn Jeff H

机构信息

Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD 20892, USA.

出版信息

Phys Med Biol. 2008 May 21;53(10):2677-92. doi: 10.1088/0031-9155/53/10/016. Epub 2008 Apr 30.

DOI:10.1088/0031-9155/53/10/016

PMID:18445873

Abstract

A hybrid method that combines the finite-difference time-domain (FDTD) method and the finite-element time-domain (FETD) method is presented for simulating radio-frequency (RF) coils in magnetic resonance imaging. This method applies a high-fidelity FETD method to RF coils, while the human body is modeled with a low-cost FDTD method. Since the FDTD and the FETD methods are applied simultaneously, the dynamic interaction between RF coils and the human body is fully accounted for. In order to simplify the treatment of the highly irregular FDTD/FETD interface, composite elements are proposed. Two examples are provided to demonstrate the validity and effectiveness of the hybrid method in high-field receive-and-transmit coil design. This approach is also applicable to general bio-electromagnetic simulations.

摘要

提出了一种结合时域有限差分（FDTD）法和时域有限元（FETD）法的混合方法，用于模拟磁共振成像中的射频（RF）线圈。该方法将高保真FETD方法应用于RF线圈，而用低成本的FDTD方法对人体进行建模。由于同时应用了FDTD和FETD方法，因此充分考虑了RF线圈与人体之间的动态相互作用。为了简化对高度不规则的FDTD/FETD界面的处理，提出了复合单元。给出了两个例子，以证明该混合方法在高场收发线圈设计中的有效性和实用性。这种方法也适用于一般的生物电磁模拟。