发表机构
The Institute for Instrumentation in Molecular Imaging (I3M), CSIC–Universitat Politècnica de València; C.J. Gorter MRI Center, Department of Radiology, Leiden University Medical Center; PhysioMRI Tech（分子成像仪器研究所（I3M），西班牙瓦伦西亚理工大学; 莱顿大学医学中心放射科 C.J. Gorter 磁共振中心; PhysioMRI Tech）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究开发了一种可穿戴、可拉伸的射频线圈，通过缝合利兹线至弹性织物实现肢体贴合，在低场MRI中提供与刚性线圈相当或更高的信噪比，并便于放置。
AI 中文摘要
目的：开发一种可穿戴、可拉伸的射频（RF）线圈，该线圈能够贴合肢体，并提高低场MRI中的填充因子。方法：通过将正弦排列的利兹线导体缝合到弹性纺织品上，制作了一种可拉伸的螺线管射频线圈。将该线圈与四种刚性线圈进行了比较，其中包括两种常规使用的设计和两种旨在隔离导体材料和可拉伸性影响的原型。通过品质因数、负载因数、发射效率和基于图像的信噪比（SNR）测量来表征性能。使用两台工作频率分别为3.53 MHz和3.04 MHz的便携式MRI系统，对一名志愿者进行了体模和体内膝关节实验。结果：所选利兹线的电性能随频率增加而下降，在3.53 MHz时成为轻微劣势。尽管如此，可拉伸线圈在两种系统中均提供了最高的体模SNR，在3.53 MHz时比性能最佳的刚性线圈高出约8%，在3.04 MHz时高出约20%。在体内实验中，其在3.53 MHz时的整体SNR比最佳刚性线圈低5%，而在3.04 MHz时高19%。与膝关节定位受限时所需的较大刚性线圈相比，相应的SNR改进约为18%和80%。结论：解剖贴合性可以补偿可拉伸低场射频线圈中利兹线随频率变化的电学局限性。所提出的设计提供了与最佳刚性设计相当或更高的SNR，同时便于在较小刚性线圈可能不实用的受试者中进行线圈放置。
英文摘要
Purpose: To develop a wearable, stretchable radio-frequency (RF) coil that conforms to the extremities and improves the filling factor in low-field MRI. Methods: A stretchable solenoid RF coil was fabricated by stitching a sinusoidally arranged Litz-wire conductor onto an elastic textile. The coil was compared with four rigid coils, including two routinely used designs and two prototypes designed to isolate the effects of conductor material and stretchability. Performance was characterized through quality-factor, loading-factor, transmit-efficiency, and image-based signal-to-noise ratio (SNR) measurements. Phantom and in-vivo knee experiments for one volunteer were performed using two portable MRI systems operating at 3.53 and 3.04 MHz. Results: The electrical performance of the selected Litz wire decreased with increasing frequency, becoming a slight disadvantage at 3.53 MHz. Nevertheless, the stretchable coil provided the highest phantom SNR in both systems, exceeding that of the best-performing rigid coil by approximately 8 % at 3.53 MHz and 20 % at 3.04 MHz. In vivo, its global SNR was 5 % lower than that of the best rigid coil at 3.53 MHz and 19 % higher at 3.04 MHz. Compared with the larger rigid coil required when knee positioning is constrained, the corresponding SNR improvements were approximately 18 % and 80 %. Conclusion: Anatomical conformity can compensate for the frequency-dependent electrical limitations of Litz wire in stretchable low-field RF coils. The proposed design provided SNR comparable to or greater than the best rigid designs while facilitating coil placement in subjects for whom smaller rigid coils may be impractical.
Comments22 pages, 9 figures
