Journal
MAGNETIC RESONANCE IN MEDICINE
Volume 73, Issue 3, Pages 939-950Publisher
WILEY-BLACKWELL
DOI: 10.1002/mrm.25188
Keywords
Phase-contrast MRI; 4D flow MRI; flow visualization; ultra-short TE; turbulent flow; high flow rate
Funding
- National Science Foundation [0730467]
- Innovative Translational Research Award from the Clinical and Translational Research Program of the University of Louisville
- Directorate For Engineering
- Div Of Chem, Bioeng, Env, & Transp Sys [0730467] Funding Source: National Science Foundation
Ask authors/readers for more resources
PurposeInaccuracy of conventional four-dimensional (4D) flow MR imaging in the presence of random unsteady and turbulent blood flow distal to a narrowing has been an important challenge. Previous investigations have revealed that shorter echo times (TE) decrease the errors, leading to more accurate flow assessments. MethodsIn this study, as part of a 4D flow acquisition, an Ultra-Short TE (UTE) method was adopted. UTE works based on a center-out radial k-space trajectory that inherently has a short TE. By employing free induction decay sampling starting from read-out gradient ramp-up, and by combining the refocusing lobe of the slice select gradient with the bipolar flow encoding gradient, TEs of approximate to 1 msec may be achieved. ResultsBoth steady and pulsatile flow regimes, and in each case a range of Reynolds numbers, were studied in an in-vitro model. Flow assessment at low and medium flow rates demonstrated a good agreement between 4D UTE and conventional 4D flow techniques. However, 4D UTE flow significantly outperformed conventional 4D flow, at high flow rates for both steady and pulsatile flow regimes. Feasibility of the method in one patient with Aortic Stenosis was also demonstrated. ConclusionFor both steady and pulsatile high flow rates, the measured flow distal to the stenotic narrowing using conventional 4D flow revealed more than 20% error compared to the ground-truth flow. This error was reduced to less than 5% using the 4D UTE flow technique. Magn Reson Med 73:939-950, 2015. (c) 2014 Wiley Periodicals, Inc.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available