In vivo multiple-mouse MRI at 7 Tesla

We developed a live high-field multiple-mouse magnetic resonance imaging method to increase the throughput of imaging studies involving large numbers of mice. Phantom experiments were performed in 7 shielded radiofrequency (RF) coils for concurrent imaging on a 7 Tesla MRI scanner outfitted with multiple transmit and receive channels to confirm uniform signal-to-noise ratio and minimal ghost artifacts across images from the different RF coils. Grid phantoms were used to measure image distortion in different positions in the coils. The brains of 7 live mice were imaged in 3D in the RF coil array, and a second array of 16 RF coils was used to 313 image the whole bodies of 16 fixed, contrast agent-perfused mice. The images of the 7 live mouse brains at 156 mu m isotropic resolution and the 16 whole fixed mice at 100 mu m isotropic resolution were of high quality and free of artifacts. We have thus shown that multiple-mouse MRI increases throughput for live and fixed mouse experiments by a factor equaling the number of RF coils in the scanner.