Volume 13 Supplement 1
Highly-Accelerated Real-Time Cine MRI using compressed sensing and parallel imaging
© Feng et al; licensee BioMed Central Ltd. 2011
Published: 2 February 2011
To develop and evaluate highly-accelerated real-time cine MRI using compressed sensing and parallel imaging.
Breath-hold cine MRI with balanced steady-steady free precession (b-SSFP) may yield non diagnostic image quality in patients with impaired breath-hold capacity and/or arrhythmias. In such patients, it may be necessary to perform real-time cine MRI. Currently, dynamic parallel imaging methods, such as TSENSE  and TGRAPPA , can be used to achieve only moderate acceleration rates (R) of 2-3 using standard body and spine coil arrays. We propose the application of a recently developed joint acceleration technique (CS-PI) that combines compressed sensing  and parallel imaging for highly-accelerated, real-time cine MRI with clinically acceptable spatiotemporal resolution.
Real-time cine MRI pulse sequences with b-SSFP readouts and TGRAPPA and CS-PI accelerations with R=4 and R=8 were implemented on 3T whole-body MRI scanners (Siemens; Tim-Trio & Verio) equipped with standard body and spine coil arrays (12 elements total). The relevant imaging parameters include: FOV=320mm x 320mm, acquisition matrix size=128x128, TE/TR=1.37/2.7ms, receiver bandwidth=1184 Hz/pixel, and flip angle=40o. The temporal resolutions were 86.4, and 43.2 ms for R = 4 and 8, respectively. Seven patients (mean age=41.5±20.7 years) undergoing clinical CMR were imaged in mid-ventricular short-axis and long-axis planes, following completion of the clinical examination using free breathing and electrocardiogram gating. The cine data sets were randomized and blinded for qualitative evaluation (image quality, artifact, noise; 1-5; lowest-highest) by a cardiologist and a radiologist. Statistical analysis was performed to compare the mean scores between the 4 groups (TGRAPPA-R4, TGRAPPA-R8, CS-PI-R4, CS-PI-R8) and between each pair of groups.
This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.