Low‐cost inductively coupled stacked wireless RF coil for MRI at 3 T

Abstract

Inductively coupled RF coils are an inexpensive and simple method to realize wireless RF coils in MRI. They are low cost and can greatly ease the MR scan setup and improve patient comfort, since they do not require bulky components such as cables, baluns, preamplifiers, and connectors. Previous works have typically used single-layer loops as wireless coils. In this work, we present a novel wireless coil, where two loops are stacked and decoupled with a shared capacitor. We found that such a stacked structure could increase the coil efficiency and SNR. Compared with the single-layer wireless coil, both electromagnetic simulation and MR experiment results demonstrate that the stacked wireless coil has a considerable SNR improvement of approximately 35%.

Detunable wireless Litzcage coil for human head MRI at 1.5 T

“…An alternative way to realize the wireless coil with a much lower cost and simpler design is through inductive coupling technology, 9–18 as illustrated in Figure 1. The inductively coupled coil can be traced back to the early days of MRI 19–21 .…”

“…Previous work has demonstrated that wireless loop coils can be detuned using a passive detuning circuit 10,17,30 . However, detuning volume‐type wireless coils is much more challenging because of their complex structure and multiple resonant modes.…”

“…However, this makes the wireless coil much more costly and bulky because parts of the RF receive chain, such as the analog-to-digital converter, clocking electronics, and data transmission, must be integrated into the coil itself. 7,8 An alternative way to realize the wireless coil with a much lower cost and simpler design is through inductive coupling technology, [9][10][11][12][13][14][15][16][17][18] as illustrated in Figure 1. The inductively coupled coil can be traced back to the early days of MRI.…”

“…Previous work has demonstrated that wireless loop coils can be detuned using a passive detuning circuit. 10,17,30 However, detuning volumetype wireless coils is much more challenging because of their complex structure and multiple resonant modes. Adding too many detuning circuits to a wireless coil would decrease the coil's quality factor, impair the SNR, and increase the cost.…”