SYSTEM AND METHOD FOR OBJECT-BASED INITIALIZATION OF MAGNETIC FIELD INHOMOGENEITY IN MAGNETIC RESONANCE IMAGING
First Claim
1. A method for estimating inhomogeneities in a magnetic field of a magnetic resonance imaging (MRI) system, the steps of the method comprising:
- a) directing the MRI system to acquire k-space data from an imaging volume at a plurality of different echo times;
b) reconstructing an image for each of the plurality of echo times using the k-space data acquired at the respective echo time;
c) estimating a distribution of magnetic susceptibility values in the imaging volume using information in the images reconstructed in step b); and
d) estimating a magnetic field inhomogeneity map from the distribution of magnetic susceptibility values estimated in step c).
2 Assignments
0 Petitions
Accused Products
Abstract
An object-based approach is used to initialize the magnetic field inhomogeneity estimation for chemical species separation, such as water-fat separation, and other imaging applications. For example, a susceptibility distribution in the subject being imaged is estimated from images reconstructed from single-echo or multi-echo k-space data and used to initialize the magnetic field inhomogeneity estimation. This approach can be applied to any complex-based chemical shift encoded chemical species separation technique and to other imaging applications, such as susceptibility-weighted imaging and quantitative susceptibility mapping. The field map can also be used to correct for image distortions and to generate magnetic field shimming values.
19 Citations
21 Claims
-
1. A method for estimating inhomogeneities in a magnetic field of a magnetic resonance imaging (MRI) system, the steps of the method comprising:
-
a) directing the MRI system to acquire k-space data from an imaging volume at a plurality of different echo times; b) reconstructing an image for each of the plurality of echo times using the k-space data acquired at the respective echo time; c) estimating a distribution of magnetic susceptibility values in the imaging volume using information in the images reconstructed in step b); and d) estimating a magnetic field inhomogeneity map from the distribution of magnetic susceptibility values estimated in step c). - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. A method for estimating inhomogeneities in a magnetic field of a magnetic resonance imaging (MRI) system, the steps of the method comprising:
-
a) directing the MRI system to acquire k-space data from an imaging volume; b) reconstructing an image from the acquired k-space data; c) estimating a distribution of magnetic susceptibility values in the imaging volume using information in the image reconstructed in step b); and d) estimating a magnetic field inhomogeneity map from the distribution of magnetic susceptibility values estimated in step c). - View Dependent Claims (20, 21)
-
Specification