  Robust and homogeneous lipid suppression is mandatory for coronary magnetic
resonance angiography (MRA) since coronary arteries are commonly embedded in
fat. However, effective large volume lipid suppression becomes challenging when
performing radial whole-heart coronary MRA and the problem may even be
exacerbated at increasing magnetic field strengths. Incomplete fat suppression
also generates artifacts, and may affect advanced motion correction methods.
The aim was to evaluate a recently reported lipid insensitive MRI method for
self-navigated coronary MRA at 3T. Lipid insensitive binomial off resonant
excitation (LIBRE) radiofrequency (RF) excitation pulses were included into a
self-navigated 3D radial GRE coronary MRA sequence at 3T. LIBRE was compared
against conventional fat saturation (FS) and binomial 1-180{\deg}-1 water
excitation (WE). First, fat suppression of all techniques was numerically
characterized using Matlab and experimentally validated in phantoms and in legs
of human volunteers. Subsequently, free-breathing self-navigated coronary MRA
was performed using the LIBRE pulse as well as FS and WE in ten volunteers.
Results obtained in the simulations were confirmed by the experimental
validations as LIBRE enabled near complete fat suppression for 3D radial
imaging in vitro and in vivo. For self-navigated whole-heart coronary MRA at
3T, fat SNR was significantly attenuated using LIBRE compared with conventional
FS. LIBRE increased the RCA vessel sharpness significantly (37 +/- 9% (LIBRE)
vs. 29 +/- 8% (FS) and 30 +/- 8% (WE), both p<0.05) and led to a significant
increase in the measured RCA vessel length to (83 +/- 31 mm (LIBRE) vs. 56 +/-
12 mm (FS) and 59 +/- 27 (WE) p<0.05). LIBRE enables robust large volume fat
suppression and significantly improves coronary artery image quality at 3T
compared to the use of conventional fat suppression and water excitation.
