Divya Varadarajan1,2, Mukund Balasubramanian2,3, Daniel J. Park1, Thomas Witzel4, Jason P. Stockmann1,2, and Jonathan R. Polimeni1,2,5
1Martinos Center for Biomedical Imaging, Charlestown, MA, United States, 2Department of Radiology, Harvard Medical School, Boston, MA, United States, 3Boston Children’s Hospital, Boston, MA, United States, 4Qbio Inc., San Carlos, CA, United States, 5Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, United States
1Martinos Center for Biomedical Imaging, Charlestown, MA, United States, 2Department of Radiology, Harvard Medical School, Boston, MA, United States, 3Boston Children’s Hospital, Boston, MA, United States, 4Qbio Inc., San Carlos, CA, United States, 5Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, United States
Here we investigate the accuracy of the standard B0 field
map acquisition, demonstrate that the estimated fields vary with several
acquisition parameters, and investigate sources of these errors.
Figure 1. The figure shows the variation of fieldmaps with
TR and plots the associated statistics of the bias.
Figure 5. Slice
select gradient reversal along with PE and FE gradient reversal (a) cancels
most of the bias in the fieldmap (b) and reduces to a mean of 0.5 Hz and a 97th
percentile of ~2 Hz (c).