Institute of Medical Physics and Radiation Protection, TH Mittelhessen University of Applied Sciences, Giessen, Germany.
Clinic of Diagnostic and Interventional Radiology, Philipps-University of Marburg, Marburg, Germany.
Magn Reson Med. 2021 Oct;86(4):2276-2289. doi: 10.1002/mrm.28843. Epub 2021 May 24.
Three 64-channel cardiac coils with different detector array configurations were designed and constructed to evaluate acceleration capabilities in simultaneous multislice (SMS) imaging for 3T cardiac MRI.
Three 64-channel coil array configurations obtained from a simulation-guided design approach were constructed and systematically evaluated regarding their encoding capabilities for accelerated SMS cardiac acquisitions at 3T. Array configuration A consists of uniformly distributed equally sized loops in an overlapped arrangement, B uses a gapped array design with symmetrically distributed equally sized loops, and C has non-uniform loop density and size, where smaller elements were centered over the heart and larger elements were placed surrounding the target region. To isolate the anatomic variation from differences in the coil configurations, all three array coils were built with identical semi-adjustable housing segments. The arrays' performance was compared using bench-level measurements and imaging performance tests, including signal-to-noise ratio (SNR) maps, array element noise correlation, and SMS acceleration capabilities. Additionally, all cardiac array coils were evaluated on a healthy volunteer.
The array configuration C with the non-uniformly distributed loop density showed the best overall cardiac imaging performance in both SNR and SMS encoding power, when compared to the other constructed arrays. The diffusion weighted cardiac acquisitions on a healthy volunteer support the favorable accelerated SNR performance of this array configuration.
Our results indicate that optimized highly parallel cardiac arrays, such as the 64-channel coil with a non-uniform loop size and density improve highly accelerated SMS cardiac MRI in comparison to symmetrically distributed loop array designs.
设计并构建了三种具有不同探测器阵列配置的 64 通道心脏线圈，以评估在 3T 心脏 MRI 中进行同步多层（SMS）成像时的加速能力。
通过仿真引导设计方法获得了三种 64 通道线圈阵列配置，并对其在 3T 加速 SMS 心脏采集方面的编码能力进行了系统评估。配置 A 由重叠排列的均匀分布的等大小线圈组成，B 采用具有对称分布的等大小线圈的缝隙阵列设计，C 则具有非均匀的线圈密度和大小，其中较小的元件位于心脏中心，较大的元件位于目标区域周围。为了将解剖变异与线圈配置的差异隔离开来，所有三个阵列线圈都使用相同的半可调外壳段构建。通过使用基准级别的测量和成像性能测试（包括信噪比（SNR）图、阵列元件噪声相关性和 SMS 加速能力）比较了阵列的性能。此外，还在健康志愿者身上评估了所有心脏阵列线圈。
与其他构建的阵列相比，具有非均匀分布的线圈密度的配置 C 显示出在 SNR 和 SMS 编码能力方面的最佳整体心脏成像性能。对健康志愿者的扩散加权心脏采集支持了这种阵列配置的有利加速 SNR 性能。
我们的结果表明，与对称分布的线圈阵列设计相比，优化的高并行心脏阵列（例如具有非均匀线圈大小和密度的 64 通道线圈）可改善高度加速的 SMS 心脏 MRI。
