Nada A, Cousins J P, Rivera A, Carr S B, Jones J, Minor C, Hetherington H P, Kim J H, Pan J W
From the Washington University in St. Louis (A.N.), School of Medicine, Mallinckrodt Institute of Radiology, St. Louis, Missouri
Department of Radiology (J.P.C., J.J., C.M., J.H.K., J.W.P.), University of Missouri, Columbia, Missouri.
AJNR Am J Neuroradiol. 2025 Apr 2;46(4):852-858. doi: 10.3174/ajnr.A8569.
7T neuroimaging has known problems with B strength, homogeneity and B susceptibility that make imaging in the inferior brain regions difficult. We investigated the utility of a decoupled 8 × 2 transceiver coil and shim insert to image the internal auditory canal (IAC) and inferior brain in comparison to the standard Nova 8/32 coil. B , B, and the T2 sampling perfection with application-optimized contrasts by using flip angle evolution sequence (SPACE) were compared by using research and standard methods in = 8 healthy adults by using a Terra system. A T2 TSE was also acquired, and 2 neuroradiologists evaluated structures in and around the IAC, blinded to the acquisition, by using a 5-point Likert scale. The Nova 8/32 coil gave lower B inferiorly compared with the whole brain while the transceiver maintained similar B throughout. SPACE images showed that the transceiver performed significantly better, e.g., the transceiver scored 4.0 ± 0.8 in the left IAC, compared with 2.5 ± 0.8 with the Nova 8/32. With T2-weighted imaging that places a premium on refocusing pulses, these results show that with improved B performance inferiorly, good visualization of the structure of the IAC and inferior brain regions is possible at 7T.
7T神经成像在磁场强度、均匀性和磁敏感性方面存在已知问题，这使得对脑下部区域进行成像变得困难。我们研究了一种解耦的8×2收发线圈和匀场插入件与标准Nova 8/32线圈相比，用于对内耳道（IAC）和脑下部进行成像的效用。通过使用Terra系统，采用研究方法和标准方法，在8名健康成年人中比较了使用翻转角演化序列（SPACE）的B值、B值以及具有应用优化对比度的T2采样完美度。还采集了T2加权快速自旋回波（T2 TSE）图像，两名神经放射科医生在不知道采集方式的情况下，使用5点李克特量表对IAC及其周围的结构进行评估。与全脑相比，Nova 8/32线圈在下方的B值较低，而收发线圈在整个区域保持相似的B值。SPACE图像显示，收发线圈的表现明显更好，例如，收发线圈在左侧IAC的评分为4.0±0.8，而Nova 8/32线圈为2.5±0.8。在重视重聚焦脉冲的T2加权成像中，这些结果表明，通过改善下方的B值性能，在7T时对内耳道和脑下部区域的结构进行良好可视化是可能的。
