一种用于7T磁共振成像的新型宽边耦合开口谐振器射频线圈  

A Novel Broadside-Coupled Split Ring Resonator Radio Frequency Coil for 7T Magnetic Resonance Imaging

作　　者：李宏伟[1] Li Hongwei(Daqing Oilfield General Hospital,Daqing Heilongjiang 163001,China)

机构地区：[1]大庆油田总医院,黑龙江大庆163001

出　　处：《医疗装备》2021年第11期35-37,共3页Medical Equipment

摘　　要：目的为了在提高透射深度的同时降低比吸收率(SAR),设计一种用于7T磁共振成像的新型宽边耦合开口谐振器(BC-SRR)射频线圈。方法该线圈由上、下两层圆形边缘耦合SRR(EC-SRR)结构构成,分析上、下层之间相对旋转角度为90°、180°、270°和360°时构成的4个模型,探讨SRR结构中裂缝数量变化对磁场分布和SAR的影响。结果在穿透深度为0~50 mm时,新型BC-SRR射频线圈的磁场强度高于传统BC-SRR及EC-SRR射频线圈;内环裂缝数量多、外环裂缝数量少的BC-SRR射频线圈的穿透深度更大且SAR更低。结论新型BC-SRR射频线圈在磁场强度、穿透深度和SAR等方面均优于传统BC-SRR及EC-SRR射频线圈。Objective A novel broadside-coupled split ring resonator(BC-SRR)radio frequency coil for 7T magnetic resonance imaging was proposed,aiming to increase penetration depth and decrease specific absorption rate(SAR).Methods The novel BC-SRR coil was composed of two circular edge-coupled SRR(EC-SRR)structures(distributed up and down).Four models formed by different relative rotate angles(90°,180°,270°and 360°)between the upper and lower layers were analyzed.In addition,the impact of the changes of gaps'number in the rings on magnetic field distribution and SAR were investigated.Results The magnetic field magnitude of the novel BC-SRR coil was higher than those of conventional BC-SRR and EC-SRR coils when the penetration depth was 0~50 mm.The BC-SRR coils with more gaps in inner loops and less gaps in outer loops had deeper penetration depth and lower SAR value.Conclusion This novel BC-SRR coil has better performance in magnetic field magnitude,penetration depth and SAR than those of conventional BC-SRR and EC-SRR coils.

关 键 词：磁共振成像 开口谐振器 射频线圈 比吸收率 

分 类 号：R445.2[医药卫生—影像医学与核医学]