Eigen-vector approach for coil sensitivity maps estimation

Patent metadata

Field	Value
Publication number	US-10914798-B2
Application number	US-201314038958-A
Country	US
Kind code	B2
Filing date	Sep 27, 2013
Priority date	Mar 30, 2012
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

A method for estimating a coil sensitivity map for a magnetic resonance (MR) image includes providing a matrix A of sliding blocks of a 3D image of coil calibration data, calculating a left singular matrix V ∥ from a singular value decomposition of A corresponding to τ leading singular values, calculating P=V ∥ V ∥ H , calculating a matrix that is an inverse Fourier transform of a zero-padded matrix P, and solving M H c r =(S r ) H c r for c r , where c r is a vector of coil sensitivity maps for all coils at spatial location r, and

M
=

(

(

1

1

…

1

0

0

…

0

…

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0

0

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0

)

⁢

(

0

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.

First claim

What is claimed is:

1. A method for reconstructing a magnetic resonance (MR) image m, comprising the steps of:
acquiring coil calibration data from a magnetic resonance imaging apparatus;
constructing a matrix A={a ij } of real numbers from 3D sliding blocks of a 3D c x ×c y ×c z image of said coil calibration data, wherein c x , c y , and c z are the x, y and z dimensions, respectively, of the coil calibration data, A has [(c x −k x +1)×(c y −k y +1)×(c z −k y +1)] columns and k x k y k z n c rows, wherein k x , k y , k z are the x, y, and z dimensions, respectively, of the sliding blocks, n c is a number of coils, i and j are row and column indices of elements a of matrix A, and a i,j is a k x k y k z ×1 column vector that represents a jth sliding block of an ith coil;
calculating a left singular matrix V ∥ from a singular value decomposition of A, wherein

V


⁡

[

v
1

,

v
2

,
…
⁢

,

v
τ

]

=

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2

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1
,
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2
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2
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)

comprises left singular vectors of A corresponding to τ leading singular values wherein H denotes a complex-conjugate transpose, v i,k is a k x k y k z ×1 column vector obtained by concatenating columns that is an i-th block in vector v k wherein v k k=1, 2, . . . , τ, is a component of V ∥ ;
calculating

P
=

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⁢

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H

=

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p

Assignees

• Siemens Healthcare Gmbh

Inventors

• Liu Jun
• Xue Hui
• Nickel Marcel Dominik
• Chang Ti-Chiun
• Nadar Mariappan S
• Lefebvre Alban
• Mueller Edgar
• Wang Qiu
• Yang Zhili
• Janardhanan Nirmal
• Zenge Michael

Classifications

• G01R33/246 Primary

  Spatial mapping of the RF magnetic field B1 · CPC title

• G01R33/5611

  Parallel magnetic resonance imaging, e.g. sensitivity encoding [SENSE], simultaneous acquisition of spatial harmonics [SMASH], unaliasing by Fourier encoding of the overlaps using the temporal dimension [UNFOLD], k-t-broad-use linear acquisition speed-up technique [k-t-BLAST], k-t-SENSE (structural details of arrays of sub-coils G01R33/3415) · CPC title

• G01R33/243 Primary

  Spatial mapping of the polarizing magnetic field · CPC title