System and method for vastly undersampled isotropic projection reconstruction with inversion recovery
First Claim
1. A method for producing an image of a subject with a magnetic resonance imaging (MRI) system, the steps of the method comprising:
- a) selecting a sampling pattern for sampling k-space, the sampling pattern including a plurality of radial projections in k-space;
b) selecting a view order that defines an order in which radial projections in the selected sampling pattern are to be acquired, the view order being selected such that any group of consecutively acquired radial projections will sample k-space in a substantially uniform distribution;
c) directing the MRI system to apply an inversion recovery (IR) radio frequency (RF) pulse to the subject such that net longitudinal magnetization in the subject is substantially inverted and begins to relax back to equilibrium;
d) directing the MRI system to acquire k-space data while the net longitudinal magnetization is recovering back to equilibrium by sampling k-space in accordance with the selected sampling pattern and the selected view order;
e) forming a data segment by grouping together consecutively acquired radial projections in the acquired k-space data starting with an initial radial projection acquired at an initial time point;
f) reconstructing an image of the subject from the data segment formed in step e), the reconstructed image depicting an image contrast defined by a recovery state of the net longitudinal magnetization at which the radial projections in the data segment were acquired.
2 Assignments
0 Petitions
Accused Products
Abstract
Described here are a system and method for obtaining a time series of images that depict a subject using an inversion recovery (“IR”) pulse sequence with a unique data acquisition scheme that allows for the retrospective identification of an image having an optimal tissue contrast. Data acquisition is performed using a radial acquisition scheme such as, preferably, a vastly undersampled isotropic projection reconstruction (“VIPR”) scheme. Using VIPR and IR, combined with a unique projection ordering, a series of three-dimensional, high spatial resolution images with multiple different image contrasts can be obtained.
-
Citations
16 Claims
-
1. A method for producing an image of a subject with a magnetic resonance imaging (MRI) system, the steps of the method comprising:
-
a) selecting a sampling pattern for sampling k-space, the sampling pattern including a plurality of radial projections in k-space; b) selecting a view order that defines an order in which radial projections in the selected sampling pattern are to be acquired, the view order being selected such that any group of consecutively acquired radial projections will sample k-space in a substantially uniform distribution; c) directing the MRI system to apply an inversion recovery (IR) radio frequency (RF) pulse to the subject such that net longitudinal magnetization in the subject is substantially inverted and begins to relax back to equilibrium; d) directing the MRI system to acquire k-space data while the net longitudinal magnetization is recovering back to equilibrium by sampling k-space in accordance with the selected sampling pattern and the selected view order; e) forming a data segment by grouping together consecutively acquired radial projections in the acquired k-space data starting with an initial radial projection acquired at an initial time point; f) reconstructing an image of the subject from the data segment formed in step e), the reconstructed image depicting an image contrast defined by a recovery state of the net longitudinal magnetization at which the radial projections in the data segment were acquired. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A method for producing a plurality of images that depict a spectrum of different image contrasts using a magnetic resonance imaging system, the steps of the method comprising:
-
a) selecting a sampling pattern for sampling k-space, the sampling pattern including a plurality of radial projections in k-space; b) selecting a temporal window; c) determining a view order that defines an order in which radial projections in the selected sampling pattern are to be acquired using the selected temporal window such that any group of consecutively acquired radial projections contained in the temporal window will substantially uniformly sample k-space; d) directing the MRI system to apply an inversion recovery (IR) radio frequency (RF) pulse to the subject such that net longitudinal magnetization in the subject is substantially inverted and begins to relax back to equilibrium; e) directing the MRI system to acquire k-space data while the net longitudinal magnetization is recovering back to equilibrium by sampling k-space in accordance with the selected sampling pattern and the selected view order; f) forming a data segment by grouping together consecutively acquired radial projections in the acquired k-space data using the selected time window; g) repeating step f) to form a plurality of data segments while sliding the temporal window by a selected time shift during each repetition of step f); and h) reconstructing a plurality of images that depict a spectrum of different image contrasts from the data segments formed in steps f) and g), the spectrum of different image contrasts being defined by a recovery state of the net longitudinal magnetization at which the radial projections in the data segment associated with a given image were acquired. - View Dependent Claims (12, 13, 14, 15, 16)
-
Specification