Evaluation of Absorber Loading Effect on the Maximum Field Strength in an MRI Room

This paper evaluates the absorber loading effect on the maximum expected field strength variability in a 30 m3 MRI room. Loading an MRI room modifies two relevant parameters of the EMFs. First, adding RF absorbers reduces the variability of the maximum field strength. This improves the predictability of the EMFs generated in the room. Second, adding RF absorbers also introduces attenuation losses, which reduces the field strength. This reduction decreases the risk of generating unintentional electromagnetic interference. The field variability is evaluated through the average and minimal insertion loss of the room. The results reveal the difference in loss distribution between the MRI room and a VIRC, which acts as a reference electromagnetic environment. This reference is used to define the minimum amount of losses required to increase the IL of the MRI room. Additionally, the Q-factor of the MRI room is presented, which strengthens previous research findings, suggesting that an MRI room is similar to a heavily loaded reverberation chamber. These results are significant as reverberation chambers are rarely used to design MRIcompatible test setups.