We have built the world's first projection MPI scanner. Please see our paper in IEEE Transactions on Medical Imaging: 10.1109/TMI.2012.2185247
Projection Magnetic Particle Imaging (MPI) can improve imaging speed by over 100-fold over traditional 3D MPI. In this work, we derive the 2D x-space signal equation, 2D image equation, and introduce the concept of signal fading and resolution loss for a projection MPI imager. We then describe the design and construction of an x-space projection MPI scanner with a field gradient of 2.35 Tesla/m across a 10 cm magnet free bore. The system has an expected resolution of 3.5 x 8.0 mm using Resovist tracer, and an experimental resolution of 3.8 x 8.4 mm resolution. The system images 2.5 cm x 5.0 cm partial FOVs at 10 frames per second, and acquires a full FOV of 10 cm x 5.0 cm in 4 seconds. We conclude by imaging a resolution phantom, a complex Cal phantom, mice injected with Resovist tracer, and experimentally confirm the theoretically predicted xspace spatial resolution.