Prospective multiaxial motion correction for fMRI

Corruption of the image time series due to interimage head motion limits th e clinical utility of functional MRI. This paper presents a method for real -time prospective correction of rotation and translation in all six degrees of rigid body motion, By incorporating an orbital navigator (ONAV) echo fo r each of the sagittal, axial, and coronal planes into the fMRI pulse seque nce, rotation and translation can be measured and the spatial orientation o f the image acquisition sequence that follows can be corrected prospectivel y in as little as 160 msec, Testing of the method using a computerized moti on phantom capable of performing complex multiaxial motion showed subdegree rotational and submillimeter translational accuracy over a range of +/-8 d egrees and +/-8 mm of motion, In vivo images demonstrate correction of simu ltaneous through-plane and in-plane motion and improved detection of fMRI a ctivation in the presence of head motion. (C) 2000 Wiley-Liss, Inc.