Abstract:
:Emerging applications of sodium bioscales derived from quantitative sodium magnetic resonance imaging assess temporal changes in regional sodium concentration over intervals that vary from hours (monitoring tissue viability in stroke) to weeks (monitoring brain tumor treatment during radiation therapy) or even years (monitoring progression of neurodegenerative disease). Accurate interpretation of such quantitative data requires precise registration between magnetic resonance imaging sessions to avoid session-to-session changes in partial volume effects between normal tissue (∼38 mM sodium concentration), lesions (variable sodium concentration), and cerebrospinal fluid (∼144 mM sodium concentration). The existing Automated Image Registration algorithm is shown to be suitable for rapid, accurate, and precise determination of the transform that aligns sodium magnetic resonance images. Implementation of this transform during image reconstruction from the k-space data is shown to produce smaller errors than conventional image-domain interpolation. Experimental results at 9.4 T and 3.0 T demonstrating this registration approach to sodium data illustrate preservation of quantification accuracy during alignment of sodium magnetic resonance images acquired from the same subject during different imaging sessions.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Atkinson IC,Lu A,Thulborn KRdoi
10.1002/mrm.23285subject
Has Abstractpub_date
2012-09-01 00:00:00pages
751-61issue
3eissn
0740-3194issn
1522-2594journal_volume
68pub_type
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