A bridged loop gap resonator (BLGR) was developed as a transmit and receive coil for a mobile insert to be used for small animal proton imaging by 1.5 T MRI devices. The insert system has its own gradient system, radio frequency (RF) transmit and receive coil, and control and signal processing unit. The reflection S11 and transmission S21 parameters, quality factor (Q), sensitivity, signal to noise ratio (SNR), and maps of the static (B0) and RF (B1) magnetic flux densities were measured. The RF coil was developed starting from a loop gap resonator (LGR) for a balanced LGR and a shielded balanced LGR for a shielded bridged balanced LGR. The purpose of developing this device is to minimize the influence of the sample and surroundings on the RF coil parameters. The final design of the BLGR does not require retuning after a sample change. A 3D image of a mouse in formalin was acquired with a fast low angle shot (FLASH) MRI sequence. The SNR was calculated from one FLASH image. The signal for SNR calculation was acquired from a gadolinium-doped water sample and the noise from the air outside of the sample. This article verifies that the BLGR is viable for small animal nuclear magnetic resonance imaging at 1.5 T and is independent of sample size and material.

中文翻译：

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用于通过 1.5 T MRI 系统对小动物成像的桥接环间隙谐振器 (BLGR)

桥接环间隙谐振器 (BLGR) 被开发为移动插入物的发射和接收线圈，用于通过 1.5 T MRI 设备进行小动物质子成像。插入系统有自己的梯度系统、射频 (RF) 发射和接收线圈，以及控制和信号处理单元。测量了反射 S11 和传输 S21 参数、品质因数 (Q)、灵敏度、信噪比 (SNR) 以及静态 (B0) 和 RF (B1) 磁通密度图。RF 线圈是从用于平衡 LGR 的环路间隙谐振器 (LGR) 和用于屏蔽桥接平衡 LGR 的屏蔽平衡 LGR 开始开发的。开发该设备的目的是尽量减少样品和周围环境对射频线圈参数的影响。BLGR 的最终设计不需要在样本更改后重新调整。使用快速低角度拍摄 (FLASH) MRI 序列获取福尔马林中小鼠的 3D 图像。SNR 是根据一张 FLASH 图像计算得出的。用于 SNR 计算的信号是从掺钆的水样和来自样品外部空气的噪声中获取的。本文验证了 BLGR 在 1.5 T 的小动物核磁共振成像中是可行的，并且与样本大小和材料无关。