Yong Pang1, Daniel Vigneron1,2,
Xiaoliang Zhang1,2
1Radiology & Biomedical
Imaging, University of California San Francisco, San Francisco, CA, United
States; 2UCSF/UC Berkeley Joint Graduate Group in Bioengineering,
San Francisco & Berkeley, CA, United States
Radiofrequency penetration is not only determined by the coil itself, but also related to the electromagnetic properties (e.g. permittivity, conductivity) and geometry of imaging samples. In this work, the RF field penetration of surface coils in human liver and brain imaging at 7T is studied numerically. Due to conductivity effects in human liver and its irregular shape, RF penetration decreases while in the brain RF penetration increases due to dielectric resonance effect. Therefore, it is necessary to have larger size coils for liver than for brain to achieve the required penetration/coverage in ultrahigh field MRI.