Numerical Calculation on Electromagnetic Energy Absorption in Pregnant Woman by RF Coil for MRI System

نویسندگان

  • toru Kikuchi
  • Kazuyuki Saito
  • Masaharu Takahashi
  • Koichi Ito
  • Hiroo Ikehira
چکیده

The numerical calculations including voxel human model with an anatomical structure for electromagnetic field and temperature rise induced by electromagnetic energy absorption have been widely investigated over the past dozen years or so. This paper presents the computational electromagnetic dosimetry inside an anatomically based pregnant woman models exposed to electromagnetic wave during magnetic resonance imaging. The two types of realistic woman models corresponding to early gestation and 26 weeks gestation were used for this study. The specific absorption rate (SAR) in and around a fetus were calculated by radiated electromagnetic wave from the birdcage coil with 1-port and 2-port feedings. Moreover, the temperature rise distributions in pregnant woman model due to the electromagnetic exposure are calculated by use of bioheat transfer equation. As the results of these calculations, the SAR and the temperature rise distributions inside the maternal body and her fetus are cleared.

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تاریخ انتشار 2009