engleski

Calculation of energy absorption in a human body model in a homogeneous pulsed high-frequency field

The purpose of this work was to estimate whether a considerable thermal absorption appears in the human body during standardized 1.5T magnetic resonance imaging (MRI) system procedures applied in medical diagnostics. Therefore, based on magnetic resonance (MR) scans of a male volunteer, a human body heterogeneous tissue model has been simulated by a finite element method using isoparametric formulation, verified before with measurements. Numerical calculation has been performed for two radiofrequency (RF) exposure systems: saddle-shaped coils and bird-cage coil. Energy deposition in terms of specific absorption, specific absorption rate (SAR) and temperature elevation in the model has been calculated for the "worst-case" imaging sequence, i.e., multislice turbo spin echo sequence. Comparison to existing recommendations shows that there is no thermal hazard at 64 MHz, corresponding to 1.5T MRI systems. However, new simulations should be performed for MR systems operating at higher frequencies.

energy absorption; high-frequency electromagnetic fields; human body

Elsevier Science S.A.