A new FDTD method for the study of MRI pulsed field gradient-induced fields in the human body

Author

Crozier, Stuart ; Zhao, Huawei ; Feng, Liu

Author_Institution

Centre For Magnetic Resonance, Queensland Univ., St. Lucia, Qld., Australia

Volume

3

fYear

2001

fDate

2001

Firstpage

2307

Abstract

In modern MRI, patients are exposed to strong, rapidly switched magnetic field gradients that may be able to elicit nerve stimulation. This paper provides the numerical results of an investigation into induced current spatial distributions inside human tissue when exposed to these pulsed magnetic field gradients. Conventional FDTD methods are unable to model these effects as the effective frequencies of the input source are less than 100 kHz or so, relatively low for FDTD calculations. A new high definition FDTD variant was developed to operate over this bandwidth and a number of body and gradient models are analysed using the new method.

Keywords

biological effects of fields; biomagnetism; biomedical MRI; finite difference time-domain analysis; health hazards; physiological models; 100 kHz; FDTD method; MRI pulsed field gradient induced fields; bandwidth; body models; gradient models; high definition FDTD variant; human body; human tissue; induced current spatial distributions; nerve stimulation; numerical results; patient safety; strong rapidly switched magnetic field gradients; Biological system modeling; Coils; Electromagnetic fields; Finite difference methods; Frequency conversion; Humans; Magnetic fields; Magnetic resonance imaging; Magnetic switching; Time domain analysis;

fLanguage

English

Publisher

ieee

Conference_Titel

Engineering in Medicine and Biology Society, 2001. Proceedings of the 23rd Annual International Conference of the IEEE

ISSN

1094-687X

Print_ISBN

0-7803-7211-5

Type

conf

DOI

10.1109/IEMBS.2001.1017237

Filename

1017237