Semiautomatic off-resonance correction in spiral imaging

✍ Scribed by Weitian Chen; Craig H. Meyer

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 419 KB
• Volume: 59
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/mrm.21599

✦ Synopsis

Abstract

Spiral scanning is a promising MRI method, but one limitation is that off‐resonance effects can cause image blurring. Most current off‐resonance correction methods for spiral imaging require an accurate field map, which is difficult to obtain in many applications. Automatic methods can perform off‐resonance correction without acquiring a field map. However, these methods are computationally inefficient and relatively prone to estimation error. This study describes a new semiautomatic off‐resonance correction method that combines an automatic method with a low resolution field map acquisition for off‐resonance correction in spiral scanning. Experiments demonstrate that this method is more robust than conventional automatic off‐resonance correction and can provide more accurate off‐resonance correction than conventional field map based methods. The proposed method is also computationally efficient and has been implemented for online reconstruction. Magn Reson Med 59:1212–1219, 2008. © 2008 Wiley‐Liss, Inc.