On the radio-frequency power requirements of human MRI

In high and ultrahigh field magnetic resonance imaging (MRI) research, computational electromagnetic techniques are now taking an important role in the design and evaluation of MRI radiofrequency (RF) coils. This paper focuses on the RF power requirements and specific absorption rate (SAR) associated with the MRI operation at different field strength. This paper also presents new techniques for achieving high-quality transmit field homogeneity simultaneously with lower total RF power deposition. The studies are done utilizing the finite difference time domain (FDTD) method and the validation of the methods is performed using ultra high field MRI volume coils.