Zypman F R
Department of Physics and Electronics, University of Puerto Rico, Humacao.
Comput Biol Med. 1996 Mar;26(2):161-75. doi: 10.1016/0010-4825(95)00037-2.
Magnetic Resonance Imaging information depends on the knowledge of the behavior of the transverse, radio frequency (RF) electromagnetic fields inside biological objects. Here we present exact results for the RF vector potential field inside and outside a cylindrical object that mimics the human body. These results are obtained by solving Maxwell Equations with appropriate boundary conditions, and take into consideration the object conductivity and dielectric constant and the presence of a cylindrical RF uniform-current-carrying coil. A computer code that evaluates RF magnetic field phase and magnitude is presented for two cases of interest: for a longitudinal and for a phi-directed current. Each of those cases is studied in free space and in the presence of a metallic shielding. The symbolic code will be of use for order-of-magnitude calculations in the clinical world and, for pedagogical uses in medical imaging courses.
磁共振成像信息依赖于对生物体内横向射频（RF）电磁场行为的了解。在此，我们给出了模拟人体的圆柱形物体内部和外部的RF矢量势场的精确结果。这些结果是通过求解具有适当边界条件的麦克斯韦方程组得到的，并考虑了物体的电导率、介电常数以及圆柱形RF均匀载流线圈的存在。针对两种感兴趣的情况给出了一个评估RF磁场相位和大小的计算机代码：纵向电流情况和沿φ方向电流情况。对每种情况都在自由空间以及存在金属屏蔽的情况下进行了研究。该符号代码将用于临床领域的量级计算，以及医学成像课程的教学用途。
