Artifact-reduced two-dimensional cine steady state free precession for myocardial blood- oxygen-level-dependent imaging.
OBJECTIVE
To minimize image artifacts in long TR cardiac phase-resolved steady state free precession (SSFP) based blood-oxygen-level-dependent (BOLD) imaging.


METHODS
Nine healthy dogs (four male, five female, 20-25 kg) were studied in a clinical 1.5 Tesla MRI scanner to investigate the effect of temporal resolution, readout bandwidth, and motion compensation on long repetition time (TR) SSFP images. Breath-held 2D SSFP cine sequences with various temporal resolutions (10-204 ms), bandwidths (239-930 Hz/pixel), with and without first-order motion compensation were prescribed in the basal, mid-ventricular, and apical along the short axis. Preliminary myocardial BOLD studies in dogs with controllable coronary stenosis were performed to assess the benefits of artifact-reduction strategies.


RESULTS
Shortening the readout time by means of increasing readout bandwidth had no observable reduction in image artifacts. However, increasing the temporal resolution in the presence of first-order motion compensation led to significant reduction in image artifacts. Preliminary studies demonstrated that BOLD signal changes can be reliably detected throughout the cardiac cycle.


CONCLUSIONS
Artifact-reduction methods used in this study provide significant improvement in image quality compared with conventional long TR SSFP BOLD MRI. It is envisioned that the methods proposed here may enable reliable detection of myocardial oxygenation changes throughout the cardiac cycle with long TR SSFP-based myocardial BOLD MRI.
Zhou
Xiangzhi
X
Department of Radiology, Northwestern University, Chicago, Illinois 60611, USA.
Tsaftaris
Sotirios A
SA
Liu
Ying
Y
Tang
Richard
R
Klein
Rachel
R
Zuehlsdorff
Sven
S
Li
Debiao
D
Dharmakumar
Rohan
R
D000818:Animals; D016477:Artifacts; D004285:Dogs; D005260:Female; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D015233:Models, Statistical; D009206:Myocardium / Q000473:pathology*; D010100:Oxygen / Q000097:blood* / Q000378:metabolism*; D013997:Time Factors
D010100:Oxygen