Premium
Subject‐specific models of susceptibility‐induced B 0 field variations in breast MRI
Author(s) -
Jordan Caroline D.,
Daniel Bruce L.,
Koch Kevin M.,
Yu Huanzhou,
Conolly Steve,
Hargreaves Brian A.
Publication year - 2013
Publication title -
journal of magnetic resonance imaging
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.563
H-Index - 160
eISSN - 1522-2586
pISSN - 1053-1807
DOI - 10.1002/jmri.23762
Subject(s) - field (mathematics) , breast mri , histogram , dipole , nuclear medicine , mean squared error , mathematics , nuclear magnetic resonance , physics , artificial intelligence , statistics , computer science , medicine , mammography , breast cancer , image (mathematics) , cancer , quantum mechanics , pure mathematics
Purpose: To rapidly calculate and validate subject‐specific field maps based on the three‐dimensional shape of the bilateral breast volume. Materials and Methods: Ten healthy female volunteers were scanned at 3 Tesla using a multi‐echo sequence that provides water, fat, in‐phase, out‐of‐phase, and field map images. A shape‐specific binary mask was automatically generated to calculate a computed field map using a dipole field model. The measured and computed field maps were compared by visualizing the spatial distribution of the difference field map, the mean absolute error, and the 80% distribution widths of frequency histograms. Results: The 10 computed field maps had a mean absolute error of 38 Hz (0.29 ppm) compared with the measured field maps. The average 80% distribution widths for the histograms of all of the computed, measured, and difference field maps are 205 Hz, 233 Hz, and 120 Hz, respectively. Conclusion: The computed field maps had substantial overall agreement with the measured field maps, indicating that breast MRI field maps can be computed based on the air–tissue interfaces. These estimates may provide a predictive model for field variations and thus have the potential to improve applications in breast MRI. J. Magn. Reson. Imaging 2013;37:227–232. © 2012 Wiley Periodicals, Inc.