Non-Contact Tracking of Involuntary Head Motions by Ultra-Wideband Radar for Improved High- And Ultra-High Field Magnetic Resonance Brain Imaging

Florian Thiel¹, Mathias Hein², Jrgen Sachs², Ulrich Schwarz², Tomasz Lindel¹, Frank Seifert¹

Subject motion appears to be a limiting factor in numerous MR imaging applications, especially at high and ultrahigh fields. For head imaging the subjects ability to maintain the same head position for a considerable period of time places restrictions on the total acquisition time. In particular, head tremor, may render certain high-resolution techniques inapplicable. Furthermore, if the very high spatial resolution offered by ultrahigh-field MR scanners shall be exploited, the displacements caused by respiration and cardiac activity have to be considered. Thus, we propose applying a novel method, based on an ultra-wideband radar technique to monitor involuntary head displacements.