Selection of high-definition 2D virtual profiles with multiple RF pulse excitations along interleaved echo-planar k-space trajectories

• Published in: Magnetic resonance in medicine 1999-02, Vol.41 (2), p.224-229
• Main Authors: Panych, Lawrence P., Oshio, Koichi
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Echo-Planar Imaging - methods; Humans; Image Processing, Computer-Assisted - methods; interleaved RF excitation; Investigative techniques, diagnostic techniques (general aspects); Medical sciences; Miscellaneous. Technology; multiple-shot RF excitation; Radiodiagnosis. Nmr imagery. Nmr spectrometry; spatially selective RF excitation
• ISSN: 0740-3194; 1522-2594
• DOI: 10.1002/(SICI)1522-2594(199902)41:2<224::AID-MRM2>3.0.CO;2-G

A method for spatially selective excitation of 2D RF profiles is reported. The method makes use of multiple shots to traverse interleaved echo‐planar trajectories in 2D k space during each RF pulse excitation. Results from each of the interleaved excitations are summed, with the net effect being the excitation of a virtual profile. The method allows for the excitation of high‐definition 2D profiles with standard gradient hardware. Signal to noise is enhanced by a factor equal to the square root of the number of interleaved excitations, compared with a single‐shot excitation. Potential applications for volume‐localized spectroscopy, functional MRI, and high‐resolution reduced‐field‐of‐view imaging are discussed. Magn Reson Med 41:224–229, 1999. © 1999 Wiley‐Liss, Inc.