Abstract:
PURPOSE:To develop and evaluate a technique for accelerating phase contrast MRI (PC-MRI) acquisitions without significant compromise in flow quantification accuracy. METHODS:PC-MRI is commonly acquired using interleaved flow-compensated (FC) and flow-encoded (FE) echoes. We hypothesized that FC data, which represent background phase, do not change significantly over time. Therefore, we proposed to undersample the FC data and use an FC view sharing (FCVS) approach to synthesize a composite FC frame for each corresponding FE frame. FCVS was evaluated in a flow phantom and healthy volunteers and compared with a standard FC/FE PC-MRI. RESULTS:The FCVS sequence resulted in an error of 0.0% for forward flow and 2.0% for reverse flow volume when compared with FC/FE PC-MRI in a flow phantom. Measurements in the common carotid arteries showed that the FCVS method had -1.16 cm/s bias for maximum peak velocity and -0.019 mL bias in total flow, when compared with FC/FE with the same temporal resolution, but double the total acquisition time. These results represent ≤1.3% bias error in velocity and volumetric flow quantification. CONCLUSION:FCVS can accelerate PC-MRI acquisitions while maintaining flow and velocity measurement accuracy when there is limited temporal variation in the FC data.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Wang D,Shao J,Rapacchi S,Middione MJ,Ennis DB,Hu Pdoi
10.1002/mrm.25133subject
Has Abstractpub_date
2015-02-01 00:00:00pages
505-13issue
2eissn
0740-3194issn
1522-2594journal_volume
73pub_type
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