Volume 13 Supplement 1

Abstracts of the 2011 SCMR/Euro CMR Joint Scientific Sessions

Open Access

Highly-Accelerated Real-Time Cine MRI using compressed sensing and parallel imaging

  • Li Feng1,
  • Ricardo Otazo1,
  • Monvadi B Srichai1,
  • Ruth P Lim1,
  • Daniel K Sodickson1 and
  • Daniel Kim1
Journal of Cardiovascular Magnetic Resonance201113(Suppl 1):P25

DOI: 10.1186/1532-429X-13-S1-P25

Published: 2 February 2011

Purpose

To develop and evaluate highly-accelerated real-time cine MRI using compressed sensing and parallel imaging.

Introduction

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 [1] and TGRAPPA [2], 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)[3] that combines compressed sensing [4] and parallel imaging for highly-accelerated, real-time cine MRI with clinically acceptable spatiotemporal resolution.

Methods

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.

Results

Figure 1 shows images of end-systolic frames in mid-ventricular short-axis and 2-chamber views. According to the Kruskal-Wallis test, the 4 groups were significantly different (p0.05): image quality, CS-PI-R4 vs. CS-PI-R8; artifact, CS-PI-R4 vs. CS-PI-R8; noise, TGRAPPA-R4 vs. CS-PI-R8, TGRAPPA-R4 vs. CS-PI-R4, CS-PI-R4 vs. CS-PI-R8. These preliminary results suggest that TGRAPPA can yield robust results at R=4, whereas CS-PI can yield robust results up to R=8.
https://static-content.springer.com/image/art%3A10.1186%2F1532-429X-13-S1-P25/MediaObjects/12968_2011_Article_1606_Fig1_HTML.jpg
Figure 1

a) Short-axis view and b) long-axis view. For each view: (top row) TGRAPPA; (bottom row) joint CS-PI; (left column) R=4; (right column) R=8.

Discussion

This study demonstrates the feasibility of performing highly-accelerated real-time cine MRI using a joint CS-PI technique. An 8-fold accelerated real-time cine MRI protocol can achieve spatial resolution of 2.5mm x 2.5mm and temporal resolution of 43.2 ms, with adequate image quality. This accelerated protocol may be useful for debilitated patients with reduced breath-hold capacity and/or arrhythmias for rapid left ventricular functional evaluation.
https://static-content.springer.com/image/art%3A10.1186%2F1532-429X-13-S1-P25/MediaObjects/12968_2011_Article_1606_Fig2_HTML.jpg
Figure 2

Plots of mean scores: (left) image quality, (middle) artifact, and (right) noise. Pairs with no significant difference are noted with p>0.05.

Authors’ Affiliations

(1)
New York University School of Medicine

References

  1. Kellman P, et al: MRM. 2001Google Scholar
  2. Breuer FA, et al: MRM. 2005Google Scholar
  3. Otazo R: MRM. 2010Google Scholar
  4. Lustig M, et al: MRM. 2007Google Scholar

Copyright

© Feng et al; licensee BioMed Central Ltd. 2011

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.

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