Abstract:
PURPOSE:The objective of this study was to determine whether a sodium phased array would improve sodium breast MRI at 3 T. The secondary objective was to create acceptable proton images with the sodium phased array in place. METHODS:A novel composite array for combined proton/sodium 3 T breast MRI is compared with a coil with a single proton and sodium channel. The composite array consists of a 7-channel sodium receive array, a larger sodium transmit coil, and a 4-channel proton transceive array. The new composite array design utilizes smaller sodium receive loops than typically used in sodium imaging, uses novel decoupling methods between the receive loops and transmit loops, and uses a novel multichannel proton transceive coil. The proton transceive coil reduces coupling between proton and sodium elements by intersecting the constituent loops to reduce their mutual inductance. The coil used for comparison consists of a concentric sodium and proton loop with passive decoupling traps. RESULTS:The composite array coil demonstrates a 2-5× improvement in signal-to-noise ratio for sodium imaging and similar signal-to-noise ratio for proton imaging when compared with a simple single-loop dual resonant design. CONCLUSION:The improved signal-to-noise ratio of the composite array gives breast sodium images of unprecedented quality in reasonable scan times.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Kaggie JD,Hadley JR,Badal J,Campbell JR,Park DJ,Parker DL,Morrell G,Newbould RD,Wood AF,Bangerter NKdoi
10.1002/mrm.24860subject
Has Abstractpub_date
2014-06-01 00:00:00pages
2231-42issue
6eissn
0740-3194issn
1522-2594journal_volume
71pub_type
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