Nicholas A. Bock

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 3D image the whole bodies of 16 fixed, contrast agent‐perfused mice. The images of the 7 live mouse brains at 156 μm isotropic resolution and the 16 whole fixed mice at 100 μm 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. Magn Reson Med, 2005.

Several theoretical parallel-imaging approaches are evaluated that seek to improve the efficiency of an MRI experiment involving multiple small samples, such as mice. The best method for our mouse phenotyping application is chosen in terms of efficiency and ease of implementation, and the approach is demonstrated at 1.5 T on a clinical scanner with an array of four shielded birdcage coils with four parallel receivers. Electronic interactions between the receiver channels in the system are quantified and a novel sensitivity-encoding (SENSE)-like postprocessing method is described to remove the resulting image ghosts. In parallel imaging with a four-coil array, the time required for three-dimensional (3D) high-resolution imaging of four mice is reduced to one-fourth the time that it would take to image the mice sequentially. Magn Reson Med 49:158–167, 2003.