Abstract:
:Corruption of the image time series due to interimage head motion limits the 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 for each of the sagittal, axial, and coronal planes into the fMRI pulse sequence, rotation and translation can be measured and the spatial orientation of the image acquisition sequence that follows can be corrected prospectively in as little as 160 msec. Testing of the method using a computerized motion phantom capable of performing complex multiaxial motion showed subdegree rotational and submillimeter translational accuracy over a range of +/-8 degrees and +/-8 mm of motion. In vivo images demonstrate correction of simultaneous through-plane and in-plane motion and improved detection of fMRI activation in the presence of head motion.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Ward HA,Riederer SJ,Grimm RC,Ehman RL,Felmlee JP,Jack CR Jrdoi
10.1002/(sici)1522-2594(200003)43:3<459::aid-mrm19subject
Has Abstractpub_date
2000-03-01 00:00:00pages
459-69issue
3eissn
0740-3194issn
1522-2594pii
10.1002/(SICI)1522-2594(200003)43:3<459::AID-MRM19journal_volume
43pub_type
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