Characterisation of Motion-Induced Field Distortions in Spectroscopic Imaging with Prospective Motion Correction

Thomas Lange¹, Daniel Nicolas Splitthoff¹, Maxim Zaitsev¹, Julian Maclaren¹

Prospective motion correction based on an optical tracking system in combination with retrospective phase correction has recently been proposed for spectroscopic imaging in the human brain and has been validated for in-plane motion. In this work, the method is assessed for through-plane motion, focussing on the characterisation of motion-induced field distortions in the VOI and evaluating the potential for real-time shimming. Through-plane motion causes stronger spectral degradation compared to in-plane motion, particularly in the frontal cortex close to the nasal cavities. For rotational motion, the field distortions may contain large second-order components, which are hard to correct in real time.