TITLE:
Induced Electromagnetic Fields Estimation in Spine Examinations of MRI Patients: A Re-Evaluation of Existing Clinical Protocols at a Hospital in Accra, Ghana
AUTHORS:
Frempong Acheampong, Theresa Dery, Rita Appiah, Daniel A. Abaye
KEYWORDS:
MRI Spine Examinations, Finite Difference Method, Faraday’s Equation
JOURNAL NAME:
Journal of Applied Mathematics and Physics,
Vol.6 No.5,
May
30,
2018
ABSTRACT: Patients undergoing Magnetic Resonance Imaging (MRI) are exposed to strong, non-uniform
static magnetic fields outside of the central imaging region, in which the
movement of the body may induce electric currents in tissues which could
possibly be harmful. The purpose of this study was to re-evaluate existing
clinical protocols by determining the induced electromagnetic (EM) fields in
MRI spine examinations. The study covered 120 MRI spine examinations at the MRI
Unit of a hospital in Accra, Ghana. A numerical model based on Faraday’s
equation was developed using the finite difference method (FDM) and MATLAB
software to compute, first, a test simulation of induced EM field intensities
and then actual measurements of induced fields on the spine. The simulation
results were peak induced electric field, 0.39 V/m and current density, 0.039
A/m2. Patient results were; calculated maximum velocity, 0.29 m/s;
peak induced electric field strength, 0.44 V/m, and current density, 0.043 A/m2.
The levels of induced EM-fields were such that they would not pose any
potential health hazards to the patients as these values were well below the
recommended guidance levels set by the Directive IEC 60601-2-33 of the European
Parliament.