Cardiac cine MR-imaging at 3T: FLASH vs SSFP.
The implications of an increase in field strength, from 1.5 T to 3 T, for routine functional cardiac examinations have been systematically investigated. Flip angle optimization was carried out for identical SSFP and FLASH cine imaging sequences at 1.5 T and 3 T, which supported the use of 20 degrees (FLASH 1.5 T and 3 T) and >60 degrees (SSFP 1.5 T and 3 T). The optimized sequences were applied in a study of cardiac function in a group of ten normal volunteers. Both SSFP and FLASH sequences showed significant SNR increases in the myocardium and blood at 3 T compared with 1.5 T, increases of 48% and 30% (myocardium and blood, respectively) for the SSFP sequence and 19% and 13% for the FLASH sequence. The SSFP sequence also showed a significant increase in CNR (22%). Image quality assessment revealed that the SSFP acquisitions were superior to FLASH at both field strengths. Although SSFP contained more artifacts at 3 T, they would not prevent its clinical use. We conclude that cardiac functional examinations at 3 T should use SSFP sequences.
Tyler
Damian J
DJ
Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, UK. damian.tyler@physiol.ox.ac.uk
Hudsmith
Lucy E
LE
Petersen
Steffen E
SE
Francis
Jane M
JM
Weale
Peter
P
Neubauer
Stefan
S
Clarke
Kieran
K
Robson
Matthew D
MD
D016477:Artifacts; D001185:Artificial Intelligence; D003326:Coronary Circulation; D004562:Electrocardiography; D006321:Heart / Q000033:anatomy & histology* / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine / Q000145:classification / Q000379:methods*; D008955:Models, Cardiovascular; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted