Abstract：
PURPOSE:Motion is a major confound of image quality in MRI. A method of retrospectively correcting the effects of rotations and translations on the acquired k-space data is presented. METHODS:In two phantom experiments of well-controlled translation and rotation, two MRI-compatible infrared cameras recorded motion data that were used subsequently to correct the position and phase of recorded k-space samples. Motion data can be acquired with a temporal resolution of 60 Hz and spatial accuracy of 0.1 mm for translations and 0.2 degree for rotations. RESULTS:Significant improvements of image quality are demonstrated. CONCLUSIONS:The key advantages of the technique are that it is easy to implement, does not interfere with or complicate MR data acquisition, and is capable of correcting distortions within a single slice. Therefore, the technique has the potential to improve upon approaches that rely on the registration or realignment of successive imaging slices.
journal_name
Med Physjournal_title
Medical physicsauthors
Marxen M,Marmurek J,Baker N,Graham SJdoi
10.1118/1.3254189subject
Has Abstractpub_date
2009-12-01 00:00:00pages
5580-5issue
12eissn
0094-2405issn
2473-4209journal_volume
36pub_type
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