Impacts of the arm and leg postures on the RF-induced heating for the human body under MRI

摘要

This paper investigates the impacts of the arm and leg postures on radio frequency (RF)-induced heating for patients exposed to the electromagnetic field from the RF coil in a 1.5T magnetic resonance imaging (MRI) system. Various arm on body postures and arm touching body postures are studied. Leg bending postures and leg touching postures are considered in the leg posture studies. The peak local specific absorption rate (SAR), which is related to the RF-induced heating, is substantially affected by the arm and leg postures. For the natural arm posture, arm on body posture and the bending leg posture, the peak local SAR increases with the arm or leg moving closer to the coil. For the arm touching body posture and the leg touching posture, the peak local SAR values can be much higher than that from the natural posture. Therefore, guidance that patient posture isn't allowed to get close to the coil or form a closed loop, is proposed to guarantee patient safety.