Free-breathing whole-heart coronary MR angiography on a clinical scanner in four minutes.
OBJECTIVE
To set up a robust and patient-friendly whole-heart protocol based on 32-receive-channel technology that will potentially allow a large part of the patient population to be addressed.


METHODS
Ten volunteers were examined on a clinical 1.5 T scanner equipped with a 32-channel data acquisition system using an experimental 32-element coil array. A magnetization-prepared, navigator-gated and -tracked 3D Cartesian balanced FFE sequence was used for whole-heart coronary MR angiography (MRA). With the use of sensitivity encoding (SENSE) and partial Fourier encoding for scan acceleration, nearly isotropic high-resolution data sets were acquired during free breathing in four minutes.


RESULTS
A high contrast and sufficient signal-to-noise ratio (SNR) were obtained, which allowed visualization of the major vessels up to the distal regions and detection of major branches. Phase encoding in the anterior-posterior (AP) direction was the most favorable SENSE configuration and allowed a reasonable scan time reduction with moderate SENSE factors.


CONCLUSIONS
The employed 32-receive channel technology enabled a robust trade-off among SNR, spatial resolution, and scan time. In this study the most robust results were obtained using the smallest possible SENSE factors for a given voxel size and scan time.
Nehrke
Kay
K
Philips Research Laboratories, Hamburg, Germany. kay.nehrke@philips.com
Börnert
Peter
P
Mazurkewitz
Peter
P
Winkelmann
Richard
R
Grässlin
Ingmar
I
D000328:Adult; D017023:Coronary Angiography / Q000379:methods*; D003331:Coronary Vessels / Q000033:anatomy & histology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D012016:Reference Values; D015203:Reproducibility of Results; D012119:Respiration; D012680:Sensitivity and Specificity; D013997:Time Factors