Junmin Liu1,
David A. Rudko1, 2, Joseph S. Gati1, Ravi S.
Menon1, 3, Maria Drangova1, 2
1Imaging
Research Laboratories, Robarts Research Institute, Shulich School of Medicine
& Dentistry, University of Western Ontario, London, ONtario, Canada; 2Department
of Medical Biophysics, Shulich School of Medicine & Dentistry, University
of Western Ontario, London, Ontario, Canada; 3Department of
Medical Biophysics, Shulich School of Medicine & Dentistry, University of
Western Ontario, London , Ontario, Canada
When a frequency mask (FM) is used for generating multi-echo susceptibility-weighted images, a cutoff frequency value (fth) must be defined for the frequency image at each echo. In this work, we present a new FM generation method which determines fth by using the criterion 2π|fth|TE =π. The performance of the proposed technique is evaluated with a set of volunteer brain images acquired at 7 T, and the results are compared with the standard frequency normalization approach, which uses the lowest frequency value in the image as fth. The proposed method produces a more robust FM and higher contrast SW images.
Keywords