SYSTEM AND METHOD FOR RECONSTRUCTING GHOST-FREE IMAGES FROM DATA ACQUIRED USING SIMULTANEOUS MULTISLICE MAGNETIC RESONANCE IMAGING

摘要

Systems and methods for combined ghost artifact correction and parallel imaging reconstruction of simultaneous multislice (“SMS”) magnetic resonance imaging (“MRI”) data are provided. Dual-polarity training data are used to generate ghost-free slice data, which are used as target data in a reconstruction kernel training process. The training data are used as source data in the reconstruction kernel training. As a result, reconstruction kernels are computed, which can be used to reconstruct images from SMS data in which slice-specific ghosting artifacts are removed.

主权项

1. A method for reconstructing images of a subject using a magnetic resonance imaging (MRI) system, the steps of the method comprising:
(a) providing to a computer system, training data acquired from a subject, wherein the training data includes first training data acquired from a plurality of different slices in the subject using a first series of alternating readout gradients, and second training data acquired from the plurality of different slices in the subject using a second series of alternating readout gradients that have opposite polarity from the first series of alternating readout gradients; (b) generating from the training data with the computer system, ghost-free data for each of the plurality of different slices in the subject; (c) generating with the computer system, positive readout data by combining k-space lines in the first training data acquired with a positive readout gradient and k-space lines in the second training data acquired with a positive readout gradient; (d) generating with the computer system, negative readout data by combining k-space lines in the first training data acquired with a negative readout gradient and k-space lines in the second training data acquired with a negative readout gradient; (e) synthesizing from the positive readout data with the computer system, first collapsed slice data that synthesizes the positive readout data from each of the plurality of different slices in the subject as having been acquired simultaneously; (f) synthesizing from the negative readout data with the computer system, second collapsed slice data that synthesizes the negative readout data from each of the plurality of different slices in the subject as having been acquired simultaneously; (g) computing with the computer system, a reconstruction kernel for each of the plurality of different slice locations in the subject using a training algorithm in which the first and second collapsed slice data are used as source data and the ghost-free data are used as target data; (h) acquiring data simultaneously from the plurality of different slices in the subject using an MRI system performing a simultaneous multislice acquisition pulse sequence; (i) reconstructing images of each of the plurality of different slices by applying the reconstruction kernels to the acquired data with the computer system, wherein the images are substantially free from ghost artifacts.