Department of Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, The Netherlands.
Department of Geriatric Medicine, Radboud university medical center, Nijmegen, The Netherlands.
Magn Reson Med. 2019 Aug;82(2):825-832. doi: 10.1002/mrm.27736. Epub 2019 Mar 21.
To demonstrate a H/ P whole human brain volume coil configuration for 3 Tesla with separate P transmit and receive components that maintains H MRS performance and delivers optimal P MRSI with H decoupling.
We developed an 8-channel P receive array coil covering the head to be used as an insert for a commercial double-tuned H/ P birdcage transmit-receive coil. This retains the possibility of using low-power rectangular pulses for H-decoupled 3D P MRSI (nominal resolution 17.6 cm ; acquisition duration 13 min) but increases the SNR with the receive sensitivity of P surface coils. The performance of the combined coil setup was evaluated by measuring H and P SNR with and without the P receive array and by assessing the effect of the receive array on the transmit efficiencies of the birdcage coil.
Compared to the birdcage coil alone, the P insert in combination with the birdcage achieved an average P SNR gain of 1.4 ± 0.4 in a center partition of the brain. The insert did not cause losses in H MRS performance and transmit efficiency, whereas for P approximately 20% more power was needed to achieve the same γB1.
The new coil configuration allows H MRSI and optimal H-decoupled 3D P MRSI, with increased SNR of the human brain without patient repositioning, for clinical and research purposes at 3 Tesla.
展示一种适用于 3T 的 H/P 全脑容积线圈配置，该配置具有独立的 P 发射和接收组件，可保持 H MRS 性能，并在 H 去耦的情况下提供最佳的 P MRSI。
我们开发了一个 8 通道的 P 接收阵列线圈，覆盖头部，用作商业双调谐 H/P 鸟笼发射-接收线圈的插入件。这保留了使用低功率矩形脉冲进行 H 去耦 3D P MRSI 的可能性（名义分辨率为 17.6cm；采集时间为 13 分钟），但增加了 P 表面线圈的接收灵敏度的 SNR。通过测量有和没有 P 接收阵列时的 H 和 P SNR，并评估接收阵列对鸟笼线圈发射效率的影响，来评估组合线圈设置的性能。
与单独的鸟笼线圈相比，P 插入件与鸟笼线圈组合使用时，在大脑中心分区处获得了 1.4±0.4 的平均 P SNR 增益。插入件不会对 H MRS 性能和发射效率造成损失，而对于 P，则需要大约 20%的更多功率才能达到相同的γB1。
新的线圈配置允许在 3T 下进行 H MRSI 和最佳的 H 去耦 3D P MRSI，同时增加了人脑的 SNR，无需患者重新定位，适用于临床和研究目的。
