Premium
Iterative optimization method for design of quantitative magnetization transfer imaging experiments
Author(s) -
Levesque Ives R.,
Sled John G.,
Pike G. Bruce
Publication year - 2011
Publication title -
magnetic resonance in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.696
H-Index - 225
eISSN - 1522-2594
pISSN - 0740-3194
DOI - 10.1002/mrm.23071
Subject(s) - magnetization transfer , computer science , magnetization , nuclear magnetic resonance , iterative method , materials science , physics , algorithm , magnetic resonance imaging , radiology , magnetic field , medicine , quantum mechanics
Quantitative magnetization transfer imaging (QMTI) using spoiled gradient echo sequences with pulsed off‐resonance saturation can be a time‐consuming technique. A method is presented for selection of an optimum experimental design for quantitative magnetization transfer imaging based on the iterative reduction of a discrete sampling of the Z ‐spectrum. The applicability of the technique is demonstrated for human brain white matter imaging at 1.5 T and 3 T, and optimal designs are produced to target specific model parameters. The optimal number of measurements and the signal‐to‐noise ratio required for stable parameter estimation are also investigated. In vivo imaging results demonstrate that this optimal design approach substantially improves parameter map quality. The iterative method presented here provides an advantage over free form optimal design methods, in that pragmatic design constraints are readily incorporated. In particular, the presented method avoids clustering and repeated measures in the final experimental design, an attractive feature for the purpose of magnetization transfer model validation. The iterative optimal design technique is general and can be applied to any method of quantitative magnetization transfer imaging. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.