In-vivo SNR in DENSE MRI: temporal and regional effects of field strength, receiver coil sensitivity, and flip angle strategies
2011 (English)In: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 29, no 2, 202-208 p.Article in journal (Refereed) Published
Aim: The influences on the SNR of DENSE MRI of field strength, receiver coil sensitivity and choice of flip angle strategy have been previously investigated individually. In this study, all of these parameters have been investigated in the same setting, and a mutual comparison of their impact on SNR is presented.
Materials and methods: Ten healthy volunteers were imaged in a 1.5T and a 3T MRI system, using standard 5 or 6 channel cardiac coils as well as 32 channel coils, with four different excitation patterns. Variation of spatial coil sensitivity was assessed by regional SNR analysis.
Results: SNR ranging from 2.8 to 30.5 was found depending on the combination of excitation patterns, coil sensitivity and field strength. The SNR at 3T was 53 ± 26% higher than at 1.5T (p<0.001), whereas spatial differences of 59 ± 26% were found in the ventricle (p<0.001). 32 channel coils provided 52 ± 29% higher SNR compared to standard 5 or 6 channel coils (p<0.001). A fixed flip angle strategy provided an excess of 50% higher SNR in half of the imaged cardiac cycle compared to a sweeping flip angle strategy, and a single phase acquisition provided a six-fold increase of SNR compared to a cine acquisition.
Conclusion: The effect of field strength and receiver coil sensitivity influences the SNR with the same order of magnitude, whereas flip angle strategy can have a larger effect on SNR. Thus, careful choice of imaging hardware in combination with adaptation of the acquisition protocol is crucial in order to realize sufficient SNR in DENSE MRI.
Place, publisher, year, edition, pages
Elsevier , 2011. Vol. 29, no 2, 202-208 p.
DENSE, strain, SNR, flip angle, coil sensitivity
Medical Laboratory and Measurements Technologies
IdentifiersURN: urn:nbn:se:liu:diva-51975DOI: 10.1016/j.mri.2010.08.016ISI: 000287390500008OAI: oai:DiVA.org:liu-51975DiVA: diva2:278377
Original Publication: Andreas Sigfridsson, Henrik Haraldsson, Tino Ebbers, Hans Knutsson and Hajime Sakuma, In-vivo SNR in DENSE MRI: temporal and regional effects of field strength, receiver coil sensitivity, and flip angle strategies, 2011, Magnetic Resonance Imaging, (29), 2, 202-208. http://dx.doi.org/10.1016/j.mri.2010.08.016 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/2009-11-252009-11-252013-09-03