Impacts of Patient Postures on the RF-induced Heating for An External Fixation Device

Abstract

This paper studies the influences of body postures on the radiofrequency (RF)-induced heating for patients with an external fixation device under 1.5 Tesla (T) and 3 $T$ magnetic resonance imaging (MRI) system. Two patient postures, the natural posture and the hand raised, were used in the study. The external fixation device is placed on the forearm of the human model. The RF-induced heating at four landmark positions, corresponding to the head scan, the cardio scan, the liver scan, and the pelvis scan were studied. The peak 1g averaged specific absorption rate (SAR) was used to evaluate the RF-induced heating. For the head landmark, the natural posture has the lowest RF-induced heating and for other landmarks, the heating of the hand raised was lowest, at both 1.5 T and 3 T. Therefore, the RF-induced heating of the external fixation device can be reduced by adopting the appropriate posture.