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Abstract #0672

Velocity Unwrap for High Resolution Slice-Selective Fourier Velocity Encoding Using Spiral SENSE

SUMMA25Jennifer Anne Steeden1, Alexander Jones1, David Atkinson2, Andrew M. Taylor1, Vivek Muthurangu1

1UCL Institute of Cardiovascular Science, London, UK, United Kingdom; 2Department of Medical Physics and Bioengineering, UCL, London, UK, United Kingdom

Quantification of peak velocity is important in the assessment of stenotic flow jets. It is possible to measure peak velocity accurately using Fourier Velocity Encoding (FVE). In this study, a fast, high-resolution slice-selective FVE sequence was developed with the use of spiral trajectories, parallel-imaging, partial-Fourier in the velocity-dimension and a novel velocity-unwrap technique. The resulting sequence was acquired within a short breath-hold. Peak velocities were compared from Doppler ultrasound (US), phase-contrast MR (PCMR) and FVE. Experiments carried out in-vitro and in-vivo showed that PCMR tended to underestimate peak velocity compared to Doppler US, whereas FVE agreed well with Doppler US.

Keywords

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