Ferromagnetic Artifacts in MRI: Minimization of Motion Effects in Long TR Acquisitions

A feasibility study is under way for a multiplexed tracking/imaging/propulsion sequence to control a ferromagnetic microdevice in the human vasculature. Ferromagnetic artifact motion can be problematic for the acquired images but we show that when the phase encoding direction is made to match the main direction of motion of the device, the acquisition of planes distant of 3.4 cm of the ferromagnetic bead used show acceptable distortions and signal loss even when the bead incurs significant motion during acquisition. At approximately 6.4 cm, no distortion or signal loss is observed. These results suggest that slow breathing motion can be measured and/or gated using the undistorted parts of the images