Abstract:
:For MR applications such as contrast-enhanced MR angiography, it is desirable to achieve simultaneously high spatial and temporal resolution. The current clinical standard uses view-sharing methods combined with parallel imaging; however, this approach still provides limited spatial and temporal resolution. To improve on the clinical standard, we present an interleaved variable density (IVD) sampling method that pseudorandomly undersamples each individual frame of a 3D Cartesian ky-kz plane combined with parallel imaging acceleration. From this dataset, time-resolved images are reconstructed with a method that combines parallel imaging with a multiplicative constraint. Total acceleration factors on the order of 20 are achieved for contrast-enhanced MR angiography of the lower extremities, and improvements in temporal fidelity of the depiction of the contrast bolus passage are demonstrated relative to the clinical standard.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Wang K,Busse RF,Holmes JH,Beatty PJ,Brittain JH,Francois CJ,Reeder SB,Du J,Korosec FRdoi
10.1002/mrm.22814subject
Has Abstractpub_date
2011-08-01 00:00:00pages
428-36issue
2eissn
0740-3194issn
1522-2594journal_volume
66pub_type
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