Optimization of a Simulated Integrated Radio-Frequency/Wireless Coil for Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) systems rely on wired radio-frequency (RF) coil arrays placed near the anatomical region of interest to acquire images. However, these wired arrays have a long setup time and RF currents induced on their cables can potentially burn nearby tissue. A novel coil design, termed an integrated RF/wireless (iRFW) coil, eliminates these issues by removing the cabled connection between the coil array and the scanner. In lieu of transmitting the acquired signal through wired connections, the iRFW coil transmits data wirelessly over the air at a WiFi frequency (2.442 GHz).Previous work has shown that the iRFW coil can be used for low data rate applications (e.g., ~10 Megabytes/sec), but further investigation at higher data rates (~300 Megabytes/sec) is needed in order to adequately transfer acquired MR image data. Electromagnetic simulations are performed in this study to computationally determine the optimal iRFW coil size and position in the MRI scanner bore. The simulations determine: 1. The similarity in MR signal-to-noise ratio between a traditional RF coil and an iRFW coil, 2. The amount of localized heating in a human subject’s body due to the transmitted wireless signal, 3. The strength of the wireless data transmission between the iRFW coil inside the scanner bore and connecting antennas outside the bore for different coil sizes and positions, and 4. The stability of the wireless transmission link for the optimal coil size and position with different subject body lengths. The optimal coil size and position are determined by considering the trade-off between reducing localized heating in human subject tissue and maximizing the transmission link between the iRFW coil and adjacent antennas. Completed simulations indicate that specific coil sizes and positions do result in an improved connection. In future work, these simulations will be validated by a physical model.