公开(公告)号：US20230221393A1

公开(公告)日：2023-07-13

申请号：US18068684

申请日：2022-12-20

Applicant: CANON MEDICAL SYSTEMS CORPORATION

Inventor： Shohei HAMANAGA

IPC: G01R33/565 ,  G01R33/24

CPC classification number: G01R33/56563 ,  G01R33/243

Abstract: An image processing apparatus according to an embodiment includes processing circuitry. The processing circuitry is configured to obtain two magnetic resonance images corresponding to two phase encoding directions opposite to each other. The processing circuitry is configured to generate a shift map related to shifting a plurality of pixels in the two magnetic resonance images, by optimizing a cost function using a first difference between the two magnetic resonance images and a second difference between two edge images generated on the basis of the two magnetic resonance images. The processing circuitry is configured to generate a correction image obtained by correcting distortions of the two magnetic resonance images on the basis of the two magnetic resonance images and the shift map.

公开(公告)号：US20220133169A1

公开(公告)日：2022-05-05

申请号：US17503718

申请日：2021-10-18

Applicant: CANON MEDICAL SYSTEMS CORPORATION

Inventor： Shohei HAMANAGA ,  Mitsuhiro BEKKU

IPC: A61B5/055 ,  G01R33/48 ,  G01R33/561

Abstract: A magnetic resonance imaging apparatus according to an embodiment includes a processing circuitry. Regarding the k-space data obtained as a result of performing multi-shot imaging that includes a plurality of shots, the processing circuitry obtains a correction coefficient, based on first-type magnetic resonance images generated using the k-space data, the correction coefficient correcting phase shifting occurring in read out direction among the plurality of shots. Then, the processing circuitry corrects the k-space data based on the correction coefficients. Moreover, the processing circuitry generates a second-type magnetic resonance image using the corrected k-space data.

公开(公告)号：US20230126958A1

公开(公告)日：2023-04-27

申请号：US18046997

申请日：2022-10-17

Applicant: CANON MEDICAL SYSTEMS CORPORATION

Inventor： Shohei HAMANAGA ,  Yuki TAKAI

IPC: A61B5/055 ,  G01R33/56

Abstract: An MRI apparatus includes a scanner configured to apply an RF pulse to an object and processing circuity configured to: set a first pulse sequence in which acquisition of a first set of MR signals is started after a first delay time from application of a first excitation pulse, and a second pulse sequence in which acquisition of a second set of MR signals is started after a second delay time from application of a second excitation pulse, the second delay time being different from the first delay time; acquire first and second sets of MR signals by causing the scanner to apply the first and second pulse sequences to the object; generate a combined dataset by averaging a first dataset based on the first set of MR signals and a second dataset based on the second set of MR signals; and reconstruct an MR image based on the combined dataset.

公开(公告)号：US20250147133A1

公开(公告)日：2025-05-08

申请号：US18904060

申请日：2024-10-01

Applicant: CANON MEDICAL SYSTEMS CORPORATION

Inventor： Masahiro ABE ,  Shohei HAMANAGA ,  Mitsuhiro BEKKU

IPC: G01R33/48 ,  G01R33/565

Abstract: In one embodiment, a phase correction method comprising: acquiring first k-space data acquired in a first readout direction and second k-space data acquired in a second readout direction that is opposite to the first readout direction; weighting first real space data obtained from the first k-space data to generate first adjusted data with a predetermined weighting in which weight coefficients vary depending on a pixel position in a readout direction and become lower in a region where a variance of a phase difference is larger than a predetermined variance; weighting second real space data obtained from the second k-space data to generate second adjusted data with the predetermined weighting; calculating a correction amount for correcting a phase difference; and correcting a phase difference between data that are different from each other in polarity of a gradient pulse in the readout direction during acquisition, by using the correction amount.