Convex gradient optimization for increased spatiotemporal resolution and improved accuracy in phase contrast MRI
Year: 2014
Type: article
Abstract: Purpose: To evaluate convex gradient optimization (CVX) for increased spatiotemporal resolution and improved accuracy for phase-contrast MRI (PC-MRI). Methods: A conventional flow-compensated and flowencoded (FCFE) PC-MRI sequence was compared with a CVX PC-MRI sequence using numerical simulations, flow phantom experiments, and in vivo experiments. Flow measurements within the ascending aorta, main pulmonary artery, and right/ left pulmonary arteries of normal volunteers (N ¼ 10) were acquired at 3T and analyzed using a conventional FCFE sequence and a CVX sequence with either higher spatial resolution or higher temporal resolution. All sequences mitigated chemical shift–induced phase errors and used equivalent breath-hold durations. Results: Chemical shift–optimized PC-MRI has increased sequence efficiency when using CVX, which can provide either higher spatial or higher temporal resolution compared with conventional FCFE PC-MRI. Numerical simulations, flow phantom experiments, and in vivo experiments indicate that CVX measurements of total flow and peak velocity are increased and more accurate when compared with FCFE. Conclusion: CVX PC-MRI increases sequence efficiency while reducing chemical shift–induced phase errors. This can be used to provide either higher spatial or higher temporal resolution than conventional chemical shift–mitigated PC-MRI methods to provide more accurate measurements of blood flow and peak velocity. Magn Reson Med 72:1552–1564, 2014. V C 2013 Wiley Periodicals, Inc.
Institution: University of California, Los Angeles
Language: English
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,000
OpenAlex ID: W2051387430