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Motion correction in MRI using an apparatus for dynamic angular position tracking (ADAPT).

A Peshkovsky·K H Knuth·J A Helpern
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Abstract

Motion during MRI examinations is a serious problem that degrades the quality of the data (images) acquired. Motion can be corrected during the postprocessing of the data; however, this approach is suboptimal and is typically limited to in-plane or translational motion. An apparatus for dynamic angular position tracking (ADAPT) for prospective angular motion correction has been developed. This application is capable of "tracking" the scanned region of interest by performing dynamic adjustments of orientation of the scanning plane. The operation of the apparatus is based on deuterium MR spectroscopy and does not rely on the use of magnetic field gradients. Orientation-sensitive deuterium quadrupolar interaction in a single crystal attached to a subject is used to monitor the angular position in magnetic fields. Measurements are performed with an independent spectrometer channel in the background of the MRI scans. This apparatus is very cost- and time-efficient because it utilizes the hardware already available on many spectrometers and can be used in parallel with MRI scans. Potentially, rotations by a fraction of one degree can be easily corrected and the angular position information can be rapidly updated.

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A Peshkovsky, K H Knuth, J A Helpern. 2003. Motion correction in MRI using an apparatus for dynamic angular position tracking (ADAPT).. https://doi.org/10.1002/mrm.10329

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