Motion artifact reduction and vessel enhancement for free-breathing navigator-gated coronary MRA using 3D k-space reordering

✍ Scribed by Michael E. Huber; David Hengesbach; René M. Botnar; Kraig V. Kissinger; Peter Boesiger; Warren J. Manning; Matthias Stuber

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 288 KB
• Volume: 45
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/mrm.1087

✦ Synopsis

Abstract

Breathing‐induced bulk motion of the myocardium during data acquisition may cause severe image artifacts in coronary magnetic resonance angiography (MRA). Current motion compensation strategies include breath‐holding or free‐breathing MR navigator gating and tracking techniques. Navigator‐based techniques have been further refined by the applications of sophisticated 2D k‐space reordering techniques. A further improvement in image quality and a reduction of relative scanning duration may be expected from a 3D k‐space reordering scheme. Therefore, a 3D k‐space reordered acquisition scheme including a 3D navigator gated and corrected segmented k‐space gradient echo imaging sequence for coronary MRA was implemented. This new zonal motion‐adapted acquisition and reordering technique (ZMART) was developed on the basis of a numerical simulation of the Bloch equations. The technique was implemented on a commercial 1.5T MR system, and first phantom and in vivo experiments were performed. Consistent with the results of the theoretical findings, the results obtained in the phantom studies demonstrate a significant reduction of motion artifacts when compared to conventional (non‐k‐space reordered) gating techniques. Preliminary in vivo findings also compare favorably with the phantom experiments and theoretical considerations. Magn Reson Med 45:645–652, 2001. © 2001 Wiley‐Liss, Inc.