School of Information Technology and Electrical Engineering, University of Queensland, Brisbane, Queensland, Australia.
Siemens Healthcare, Brisbane, Australia.
Magn Reson Med. 2018 Mar;79(3):1804-1816. doi: 10.1002/mrm.26804. Epub 2017 Jun 22.
We present the initial in vivo imaging results of an open architecture eight-channel parallel transmission (pTx) transceive radiofrequency (RF) coil array that was designed and constructed for static and dynamic 7T MRI of the knee and ankle joints.
The pTx coil has a U-shaped dual-row configuration (200 mm overall length longitudinally) that allows static and dynamic imaging of the knee and ankle joints at various postures and during active movements. This coil structure, in combination with B shimming, allows flexible configuration of B transmit profiles, with good homogeneity over 120-mm regions of interest. This coil enabled high-resolution gradient echo (e.g., 3D dual-echo steady state [DESS] and 3D multiecho data image combination [MEDIC]) and turbo spin echo (TSE) imaging (e.g., with proton density weighting [PDw], PDw with fat saturation, and T and T weightings) with local RF energy absorption rates well below regulatory limits.
High-resolution 2D and 3D image series (e.g., 0.3 mm in-plane resolution for TSE, 0.47 mm isotropic for DESS and MEDIC) were obtained from the knee and ankle joints with excellent tissue contrast. Dynamic imaging during continuous knee and ankle flexion-extension cycles were successfully acquired.
The new open pTx coil array provides versatility for high-quality static and dynamic MRI of the knee and ankle joints at 7T. Magn Reson Med 79:1804-1816, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
我们介绍了一种开放架构的八通道并行发射（pTx）收发射频（RF）线圈阵列的初步体内成像结果，该线圈阵列是为 7T 膝关节和踝关节的静态和动态 MRI 设计和构建的。
pTx 线圈采用 U 形双排配置（纵向总长度为 200mm），可在各种姿势下对膝关节和踝关节进行静态和动态成像，并在主动运动期间进行成像。这种线圈结构与 B 匀场相结合，允许灵活配置 B 发射轮廓，在 120mm 的感兴趣区域内具有良好的均匀性。该线圈能够实现高分辨率梯度回波（例如，3D 双回波稳态[DESS]和 3D 多回波数据图像组合[MEDIC]）和涡轮自旋回波（TSE）成像（例如，具有质子密度加权[PDw]、PDw 带脂肪饱和、T 和 T 加权），局部射频能量吸收率远低于规定限值。
从膝关节和踝关节获得了高分辨率的 2D 和 3D 图像系列（例如，TSE 的 0.3mm 平面分辨率，DESS 和 MEDIC 的 0.47mm 各向同性分辨率），具有出色的组织对比度。成功采集了连续膝关节和踝关节屈伸循环期间的动态图像。
新的开放 pTx 线圈阵列为 7T 膝关节和踝关节的高质量静态和动态 MRI 提供了多功能性。磁共振医学 79：1804-1816，2018。©2017 年国际磁共振医学学会。
