公开(公告)号：US12045956B2

公开(公告)日：2024-07-23

申请号：US17339345

申请日：2021-06-04

Applicant: GE PRECISION HEALTHCARE LLC

Inventor： Lei Gao ,  Juan Gao ,  Gaohong Wu ,  Yongchuan Lai

IPC: G06T5/50 ,  G01R33/56 ,  G01R33/563 ,  G01R33/565 ,  G06T5/20

CPC classification number: G06T5/50 ,  G01R33/5608 ,  G01R33/56341 ,  G01R33/56509 ,  G06T5/20 ,  G06T2207/10088 ,  G06T2207/20212

Abstract: A magnetic resonance (MR) imaging method of correcting nonuniformity in diffusion-weighted (DW) MR images of a subject is provided. The method includes applying a DW pulse sequence along a plurality of diffusion directions with one or more numbers of excitations (NEX), and acquiring a plurality of DW MR images of the subject along the plurality of diffusion directions with the one or more NEX. The method also includes deriving a reference image and a base image based on the plurality of DW MR images, generating a nonuniformity factor image based on the reference image and the base image, and combining the plurality of DW MR images into a combined image. The method also includes correcting nonuniformity of the combined image using the nonuniformity factor image, and outputting the corrected image.

公开(公告)号：US20240192299A1

公开(公告)日：2024-06-13

申请号：US18079147

申请日：2022-12-12

Applicant: GE Precision Healthcare LLC

Inventor： Hua Li ,  Lei Gao ,  Gaohong Wu

IPC: G01R33/565 ,  G01R33/48 ,  G01R33/563

CPC classification number: G01R33/56518 ,  G01R33/4818 ,  G01R33/56341

Abstract: A method for correcting diffusion-weighted echo-planar imaging data (DW-EPI) includes obtaining a first reference scan with no diffusion gradients applied, a second reference scan with a diffusion gradient applied only along a frequency direction, a third reference scan with the diffusion gradient applied only along a phase direction, and a fourth reference scan with the diffusion gradient applied only along a slice direction acquired utilizing an MRI scanner, wherein the reference scans lack phase encoding. The method includes obtaining DW-EPI data acquired utilizing the MRI scanner, wherein the DW-EPI data includes phase errors due to oscillatory eddy currents causing time-varying Bo shift. The method includes generating a phase correction factor based on the reference scans and correcting the phase errors due to the oscillatory eddy currents in the DW-EPI data independent of diffusion gradient direction utilizing the phase correction factor to generate corrected DW-EPI data.

公开(公告)号：US12123933B2

公开(公告)日：2024-10-22

申请号：US18079147

申请日：2022-12-12

Applicant: GE Precision Healthcare LLC

Inventor： Hua Li ,  Lei Gao ,  Gaohong Wu

IPC: G01V3/00 ,  G01R33/48 ,  G01R33/563 ,  G01R33/565

CPC classification number: G01R33/56518 ,  G01R33/4818 ,  G01R33/56341

Abstract: A method for correcting diffusion-weighted echo-planar imaging data (DW-EPI) includes obtaining a first reference scan with no diffusion gradients applied, a second reference scan with a diffusion gradient applied only along a frequency direction, a third reference scan with the diffusion gradient applied only along a phase direction, and a fourth reference scan with the diffusion gradient applied only along a slice direction acquired utilizing an MRI scanner, wherein the reference scans lack phase encoding. The method includes obtaining DW-EPI data acquired utilizing the MRI scanner, wherein the DW-EPI data includes phase errors due to oscillatory eddy currents causing time-varying B0 shift. The method includes generating a phase correction factor based on the reference scans and correcting the phase errors due to the oscillatory eddy currents in the DW-EPI data independent of diffusion gradient direction utilizing the phase correction factor to generate corrected DW-EPI data.

公开(公告)号：US20220392035A1

公开(公告)日：2022-12-08

申请号：US17339345

申请日：2021-06-04

Applicant: GE PRECISION HEALTHCARE LLC

Inventor： Lei Gao ,  Juan Gao ,  Gaohong Wu ,  Yongchuan Lai

IPC: G06T5/50 ,  G06T5/20 ,  G01R33/56 ,  G01R33/563 ,  G01R33/565

Abstract: A magnetic resonance (MR) imaging method of correcting nonuniformity in diffusion-weighted (DW) MR images of a subject is provided. The method includes applying a DW pulse sequence along a plurality of diffusion directions with one or more numbers of excitations (NEX), and acquiring a plurality of DW MR images of the subject along the plurality of diffusion directions with the one or more NEX. The method also includes deriving a reference image and a base image based on the plurality of DW MR images, generating a nonuniformity factor image based on the reference image and the base image, and combining the plurality of DW MR images into a combined image. The method also includes correcting nonuniformity of the combined image using the nonuniformity factor image, and outputting the corrected image.

公开(公告)号：US10809339B2

公开(公告)日：2020-10-20

申请号：US15927218

申请日：2018-03-21

Applicant: GE Precision Healthcare LLC

Inventor： Ke Li ,  Gaohong Wu ,  Eric Printz ,  Kenichi Kanda ,  Margaret Ann Wiza

IPC: G01R33/56 ,  G01R33/563 ,  A61B5/055 ,  G01R33/54 ,  G01R33/483

Abstract: Methods and systems for performing magnetic resonance diffusion weighted imaging of an object is provided. The method includes applying a plurality of diffusion gradients to a plurality of image slices of the object during a plurality of repetition times via an MRI system. A different diffusion gradient of the plurality is applied to each image slice during the same repetition time.