公开(公告)号：US11367227B2

公开(公告)日：2022-06-21

申请号：US16941015

申请日：2020-07-28

Applicant: CANON MEDICAL SYSTEMS CORPORATION

Inventor： Karthikayan Balakrishnan ,  Kent C. Burr

IPC: G06T11/00 ,  G06T7/10 ,  G06T15/08 ,  G06T7/90

Abstract: A method of imaging includes obtaining projection data for an object representing an intensity of radiation detected along a plurality of rays through the object, obtaining an outline of the object via a secondary imaging system, the secondary imaging system using non-ionizing radiation, determining, based on the outline, a model and model parameters for the object, calculating, based on the model and the model parameters, a volumetric attenuation map for the object, and reconstructing, based on the projection data and the volumetric attenuation map, an attenuation-corrected volumetric image.

公开(公告)号：US11241211B2

公开(公告)日：2022-02-08

申请号：US16816953

申请日：2020-03-12

Applicant: CANON MEDICAL SYSTEMS CORPORATION

Inventor： Wenyuan Qi ,  Yi Qiang ,  Karthikayan Balakrishnan ,  Yujie Lu

IPC: A61B6/00 ,  A61B6/03 ,  G01T1/29 ,  G06T11/00

Abstract: A method and apparatus is provided to perform dead-time correction in a positron emission tomography (PET) by estimating a full singles spectrum using a scatter model. The scatter model can use a Monte Carlo method, a radiation transfer equation method, an artificial neural network, or an analytical expression. The scatter model simulates scatter based on an emission image/map and an attenuation image/map to estimate Compton scattering. In the full singles spectrum, the singles counts with energies less than 511 keV are determined from the simulated scatter. The attenuation image can be generated based on X-ray computed tomography or based on applying a joint-estimation to PET data.

公开(公告)号：US20210282732A1

公开(公告)日：2021-09-16

申请号：US16816953

申请日：2020-03-12

Applicant: Canon Medical Systems Corporation

Inventor： Wenyuan QI ,  Yi Qiang ,  Karthikayan Balakrishnan ,  Yujie Lu

IPC: A61B6/00 ,  A61B6/03 ,  G01T1/29

Abstract: A method and apparatus is provided to perform dead-time correction in a positron emission tomography (PET) by estimating a full singles spectrum using a scatter model. The scatter model can use a Monte Carlo method, a radiation transfer equation method, an artificial neural network, or an analytical expression. The scatter model simulates scatter based on an emission image/map and an attenuation image/map to estimate Compton scattering. In the full singles spectrum, the singles counts with energies less than 511 keV are determined from the simulated scatter. The attenuation image can be generated based on X-ray computed tomography or based on applying a joint-estimation to PET data.

公开(公告)号：US11663735B2

公开(公告)日：2023-05-30

申请号：US17015670

申请日：2020-09-09

Applicant: CANON MEDICAL SYSTEMS CORPORATION

Inventor： Karthikayan Balakrishnan ,  Kent C. Burr

IPC: G06K9/00 ,  G06F1/00 ,  G06T7/70 ,  A61B6/04 ,  G06T7/00 ,  A61B6/03 ,  A61B90/00

CPC classification number: G06T7/70 ,  A61B6/0407 ,  A61B6/0492 ,  G06T7/0012 ,  A61B6/032 ,  A61B6/037 ,  A61B2090/3937 ,  A61B2090/3979 ,  G06T2207/10048 ,  G06T2207/30004 ,  G06T2207/30204

Abstract: Optical sensors and optical markers are placed on components in a medical system to provide calibration and alignment, such as on a patient transportation mechanism and spatially separated medical diagnostic devices. Image processing circuitry uses the data captured by these optical devices to coordinate their movements and/or position. This enables scans that were captured in multiple medical diagnostic devices to be accurately aligned.