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Title: Measuring distributions by phase encoding
Purpose

We propose a method to acquiredistribution plots by encoding ininstead of image space. Using this method,data is acquired in a different way from traditional spatialmapping, and allows for quick measurement of high dynamic rangedata.

Methods

To encode in, we acquire multiple projections of a slice, each along the same direction, but using a different phase sensitivity to. Using a convex optimization formulation, we reconstruct histograms of thedistribution estimates of the slice.

Results

We verify in vivodistribution measurements by comparing measured distributions to distributions calculated from reference spatialmaps using the Earth Mover's Distance. Phantom measurements using a surface coil show that for increased spatialvariations, measureddistributions using the proposed method more accurately estimate the distribution than a low‐resolution spatialmap, resulting in a 37% Earth Mover's Distance decrease while using fewer measurements.

Conclusion

We propose and validate the performance of a method to acquiredistribution information directly without acquiring a spatialmap. The method may provide faster estimates of afield for applications that do not require spatiallocalization, such as the transmit gain calibration of the scanner, particularly for high dynamicranges. Magn Reson Med 77:229–236, 2017. © 2016 Wiley Periodicals, Inc.

 
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NSF-PAR ID:
10114960
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Magnetic Resonance in Medicine
Volume:
77
Issue:
1
ISSN:
0740-3194
Page Range / eLocation ID:
p. 229-236
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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