AA Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA.
Magn Reson Med. 2011 Oct;66(4):1198-208. doi: 10.1002/mrm.22906. Epub 2011 Mar 23.
Diffusion and functional magnetic resonance imaging of the spinal cord remain challenging due to the small cross-sectional size of the cord and susceptibility-related distortions. Although partially addressable through parallel imaging, few highly parallel array coils have been implemented for the cervical cord. Here, we developed a 32-channel coil that fully covers the brain and c-spine and characterized its performance in comparison with a commercially available head/neck/spine array. Image and temporal signal-to-noise ratio were, respectively, increased by 2× and 1.8× in the cervical cord. Averaged g-factors at 4× acceleration were lowered by 22% in the brain and by 39% in the spinal cord, enabling 1-mm isotropic R = 4 multi-echo magnetization prepared gradient echo of the full brain and c-spine in 3:20 min. Diffusion imaging of the cord at 0.6 × 0.6 × 5 mm(3) resolution and tractography of the full brain and c-spine at 1.7-mm isotropic resolution were feasible without noticeable distortion. Improvements of this nature potentially enhance numerous basic and clinical research studies focused on spinal and supraspinal regions.
脊髓的弥散和功能磁共振成像仍然具有挑战性,这是由于脊髓的横截面积小和与磁化率相关的失真。虽然部分可以通过并行成像来解决,但很少有高度并行的阵列线圈被应用于颈椎。在这里,我们开发了一个 32 通道的线圈,完全覆盖了大脑和颈椎,并将其性能与商业上可用的头部/颈部/脊柱阵列进行了比较。在颈椎中,图像和时间信号噪声比分别增加了 2 倍和 1.8 倍。在大脑中,平均 g 因子在 4 倍加速下降低了 22%,在脊髓中降低了 39%,从而能够在 3:20 分钟内对整个大脑和颈椎进行 1 毫米各向同性 R = 4 多回波磁化准备梯度回波。在 0.6 × 0.6 × 5 毫米(3)分辨率下对脊髓进行弥散成像,以及在 1.7 毫米各向同性分辨率下对整个大脑和颈椎进行束追踪是可行的,没有明显的失真。这种性质的改进有可能增强许多专注于脊髓和脊髓以上区域的基础和临床研究。