Quantitative evaluation of nonrepetitive phase-encoding orders for first-pass, 3D contrast-enhanced MR angiography

✍ Scribed by Alan H. Wilman; Timothy C.H. Yep; Osama Al-Kwifi

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 280 KB
• Volume: 46
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/mrm.1225

✦ Synopsis

Abstract

In this work, a detailed quantitative comparison was made of many alternative phase‐encoding strategies for first‐pass 3D MR angiography where each phase encode is only sampled once during the transient passage of contrast agent. A series of standard sequential and centric phase‐encoding orders including elliptical centric were tested, as well as a new order called elliptical sequential. The characteristics of the different phase‐encoding orders were tested using a computer simulation followed by experimental verification using a variable flip angle scheme. The characteristics to be considered included: arterial intensity, arterial‐to‐venous contrast, degree of artifact, and the blurring of the point‐spread function. By making use of a wide range of start times and a rapidly varying contrast curve, the quantitative results clearly indicate the widely varying merits of each phase‐encoding order. In general, when an optimal start time is used techniques that sample the low k‐space views most compactly will produce the best results; however, the same methods are more problematic when the bolus arrival time deviates substantially from that expected. Magn Reson Med 46:541–547, 2001. © 2001 Wiley‐Liss, Inc.