Automated determination of the resonance frequencies of protons for magnetic resonance examinations

Patent metadata

Field	Value
Publication number	US-2016238683-A1
Application number	US-201514620582-A
Country	US
Kind code	A1
Filing date	Feb 12, 2015
Priority date	Feb 12, 2015
Publication date	Aug 18, 2016
Grant date	—

Abstract

In a method and a magnetic resonance (MR) system for automated determination of the resonance frequency of a nucleus for magnetic resonance examinations, at least one MR signal is detected, and is Fourier-transformed into a spectrum composed of elements that can be represented as a vector. An analysis of the spectrum is conducted, wherein at least two cross-correlation coefficients of at least one model spectrum are determined by use of the measured spectrum. Prior to the analysis, a spectrum matrix having at least two vectors is determined from the spectrum, with each vector of the spectrum matrix being formed using all or some of the spectrum.

First claim

I claim as my invention:

1 . A method for automated determination of the resonance frequency or resonance frequencies of an atomic nucleus for magnetic resonance examinations, comprising:
operating a magnetic resonance data acquisition apparatus to acquire at least one magnetic resonance signal; providing said at least one magnetic resonance signal to a computer and, in said computer, Fourier-transforming said at least one signal into a spectrum comprised of elements that can be represented as a vector; in said computer, generating a spectrum matrix comprising at least two vectors determined from said spectrum, each of said at least two vectors being formed using at least a portion of said spectrum; in said computer, automatically analyzing said spectrum using said spectrum matrix, and deriving at least two cross-correlation coefficients therefrom for a model spectrum; and making said model spectrum available in electronic form at an output of said computer.

2 . A method as claimed in claim 1 comprising, in said computer, shifting a position of said spectrum, or portions thereof, in said at least two vectors of the spectrum matrix with respect to each other.

3 . A method as claimed in claim 2 comprising, in said computer, determining a number of the elements in each of said at least two vectors of said spectrum matrix as a function of a number of elements of said spectrum and as a function of displacement steps in said shifting of said spectrum.

4 . A method as claimed in claim 1 comprising always using an entirety of said spectrum, or always using a same part of said spectrum, for forming said at least two vectors of said spectrum matrix.

5 . A method as claimed in claim 1 comprising forming said at least two vectors of said spectrum matrix by adding elements having a predetermined numerical value to said spectrum or a portion thereof.

6 . A method as claimed in claim 5 wherein said numerical value is zero.

7 . A method as claimed in claim 5 comprising forming a first of said at least two vectors by first elements occupied by the added elements and by remaining elements that are occupied by elements of the spectrum, and forming subsequent vectors after said first vectors by shifting said spectrum or a portion thereof by one element with respect to a first element in said first vector.

8 . A method as claimed in claim 1 comprising using different or only partially identical portions of said spectrum for forming said at least two vectors of said spectrum matrix.

9 . A method as claimed in claim 1 comprising forming said at least two vectors as a vector in the group consisting of row vectors and column vectors.

10 . A method as claimed in claim 1 comprising combining model spectra into a model spectra matrix by forming a vector of said model spectrum matrix from each model spectrum.

11 . A method as claimed in claim 10 comprising forming each vector of said model spectra matrix from each model spectrum.

12 . A method as claimed in claim 10 comprising partitioning said spectrum matrix and said model spectrum matrix into sub-matrices, and analyzing said sub-matrices one at a time in said computer.

13 . A method as claimed in claim 12 comprising forming said sub-matrices as a function of a size of at least one cache of said computer that is employed by said computer to form said sub-matrices and analyze said spectrum.

14 . A method as claimed in claim 1 comprising operating said magnetic resonance data acquisition apparatus to acquire an FID signal as said at least one magnetic resonance signal.

15 . A magnetic resonance apparatus comprising:
a magnetic resonance data acquisition unit; operating a magnetic resonance data acquisition apparatus to acquire at least one magnetic resonance signal; a computer provided with said at least one magnetic resonance signal, said computer being configured to Fourier-transform said at least one signal into a spectrum comprised of elements that can be represented as a vector; said computer being configured to generate a spectrum matrix comprising at least two vectors determined from said spectrum, each of said at least two vectors being formed using at least a portion of said spectrum; said computer being configured to automatically analyze said spectrum using said spectrum matrix, and to derive at least two cross-correlation coefficients therefrom for a model spectrum; and said computer being configured to make said model spectrum available in electronic form at an output of said computer.

Assignees

• Siemens Ag

Inventors

• Campagna Swen

Classifications

• G01R33/4828

  Resolving the MR signals of different chemical species, e.g. water-fat imaging · CPC title

• G01R33/4625 Primary

  Processing of acquired signals, e.g. elimination of phase errors, baseline fitting, chemometric analysis · CPC title

• G01R33/54 Primary

  Signal processing systems, e.g. using pulse sequences {; Generation or control of pulse sequences; Operator console} · CPC title