Work

Improved respiratory self‐navigation for 3D radial acquisitions through the use of a pencil‐beam 2D‐T2‐prep for free‐breathing, whole‐heart coronary MRA

Year: 2017

Type: article

Abstract: Purpose In respiratory self‐navigation (SN), signal from static structures, such as the chest wall, may complicate motion detection or introduce post‐correction artefacts. Suppressing signal from superfluous tissues may therefore improve image quality. We thus test the hypothesis that SN whole‐heart coronary magnetic resonance angiography (MRA) will benefit from an outer‐volume suppressing 2D‐T2‐Prep and present both phantom and in vivo results. Methods A 2D‐T2‐Prep and a conventional T2‐Prep were used prior to a free‐breathing 3D‐radial SN sequence. Both techniques were compared by imaging a home‐built moving cardiac phantom and by performing coronary MRA in nine healthy volunteers. Reconstructions were performed using both a reference‐based and a reference‐independent approach to motion tracking, along with several coil combinations. Signal‐to‐noise ratio (SNR) and contrast‐to‐noise ratio (CNR) were compared, along with vessel sharpness (VS). Results In phantoms, using the 2D‐T2‐Prep increased SNR by 16% to 53% and mean VS by 8%; improved motion tracking precision was also achieved. In volunteers, SNR increased by an average of 29% to 33% in the blood pool and by 15% to 25% in the myocardium, depending on the choice of reconstruction coils and algorithm, and VS increased by 34%. Conclusion A 2D‐T2‐Prep significantly improves image quality in both phantoms and volunteers when performing SN coronary MRA. Magn Reson Med 79:1293–1303, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

Source: Magnetic Resonance in Medicine

DOI: 10.1002/mrm.26764