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公开(公告)号:US20250012937A1
公开(公告)日:2025-01-09
申请号:US18348479
申请日:2023-07-07
Applicant: CANON MEDICAL SYSTEMS CORPORATION
Inventor: Xiaohui ZHAN , Ruoqiao ZHANG , Ilmar HEIN
Abstract: A method of determining a position offset includes receiving a first detection result from a first pixel of a plurality of pixels of a radiation detector, wherein the plurality of pixels are disposed on an incident side of the radiation detector on which an anti-scatter grid (ASG) is arranged, the plurality of pixels being aligned in at least a channel direction; receiving a second detection result from a second pixel of the plurality of pixels, wherein a septa of the ASG is arranged over a portion of the first pixel but is not arranged over any portion of the second pixel as viewed from the incident side of the radiation detector; estimating a positional offset of the septa of the ASG, based on the first detection result and the second detection result.
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2.
公开(公告)号:US20230263499A1
公开(公告)日:2023-08-24
申请号:US18306773
申请日:2023-04-25
Applicant: CANON MEDICAL SYSTEMS CORPORATION
Inventor: Xiaohui ZHAN , Xiaofeng NIU , Ilmar HEIN
CPC classification number: A61B6/585 , A61B6/4241 , A61B6/032 , A61B6/4447 , A61B6/583 , G06T7/10 , A61B6/4035 , G01T7/005 , G06T11/005 , G06T2207/30004 , G06T2211/40 , G06T2207/10081
Abstract: A method and a system for providing calibration for a polychromatic photon counting detector forward counting model. Measurements with multiple materials and known path lengths are used to calibrate the photon counting detector counting response of the forward model. The flux independent weighted bin response function is estimated using the expectation maximization method, and then used to estimate the pileup correction terms at plural tube voltage settings for each detector pixel. The beam hardening corrections are then applied to the measured projection data sinogram, and the corrected sinogram is reconstructed to the counting image at the selected single energy.
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公开(公告)号:US20250152116A1
公开(公告)日:2025-05-15
申请号:US18509791
申请日:2023-11-15
Applicant: CANON MEDICAL SYSTEMS CORPORATION
Inventor: Ilmar HEIN , Xiaohui ZHAN , Ruoqiao ZHANG
IPC: A61B6/42
Abstract: A method of imaging includes analyzing a first image to detect objects in the first image and corresponding features of the objects; based on a detection result of a first object having a corresponding first object feature in the first image, selecting an action corresponding to the first object and the first object feature from a database; determining an updated set of scan parameters based on the selected action; and adjusting at least one of the table, the X-ray source, the X-ray detector, and the arm based on the updated set of scan parameters.
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公开(公告)号:US20220296202A1
公开(公告)日:2022-09-22
申请号:US17206873
申请日:2021-03-19
Applicant: CANON MEDICAL SYSTEMS CORPORATION
Inventor: Xiaohui ZHAN , Ilmar HEIN , Xiaofeng NIU
IPC: A61B6/00
Abstract: An apparatus, system and method for calibrating an x-ray apparatus including acquiring sinogram data by scanning a symmetrical phantom using a plurality of detector channels; generating mirror-copied sinogram data by mirror-copying at least one of first sinogram data and second sinogram data of the acquired sinogram data, wherein the first sinogram data and the second sinogram data are generated by dividing the sinogram data at a center detector channel of the plurality of detector channels; outputting a first reconstructed image by reconstructing the mirror-copied sinogram data; and determining a calibration parameter based on the first reconstructed image.
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公开(公告)号:US20210007694A1
公开(公告)日:2021-01-14
申请号:US16509369
申请日:2019-07-11
Applicant: Canon Medical Systems Corporation
Inventor: Ilmar HEIN , Zhou Yu , Efren Lee
Abstract: A method and apparatus is provided that uses a deep learning (DL) network together with a multi-resolution detector to perform X-ray projection imaging to provide improved resolution similar to a single-resolution detector but at lower cost and less demand on the communication bandwidth between the rotating and stationary parts of an X-ray gantry. The DL network is trained using a training dataset that includes input data and target data. The input data includes projection data acquired using a multi-resolution detector, and the target data includes projection data acquired using a single-resolution, high-resolution detector. Thus, the DL network is trained to improve the resolution of projection data acquired using a multi-resolution detector. Further, the DL network is can be trained to additional correct other aspects of the projection data (e.g., noise and artifacts).
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公开(公告)号:US20250127467A1
公开(公告)日:2025-04-24
申请号:US18490568
申请日:2023-10-19
Applicant: CANON MEDICAL SYSTEMS CORPORATION
Inventor: Xiaohui ZHAN , Ilmar HEIN , Ruoqiao ZHANG
Abstract: A photon-counting imaging system is provided. The system includes a photon-counting detector and processing circuitry. The detector acquires, from an imaging object, projection data for a plurality of projection views. The detector has a plurality of detector pixels that are arranged in both a channel direction and a segment direction on a surface of the detector. The processing circuitry obtains the projection data acquired by the detector. The projection data includes first and second projection data. The processing circuitry processes, with a first energy bin setting, the first projection data, the first energy bin setting having m energy bins, and processes, with a second energy bin setting, the second projection data, the second energy bin setting having n energy bins, where n>m. The processing circuitry generates, based on the processed first projection data and the processed second projection data, a material decomposition image of the imaging object.
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7.
公开(公告)号:US20240016459A1
公开(公告)日:2024-01-18
申请号:US17862624
申请日:2022-07-12
Applicant: CANON MEDICAL SYSTEMS CORPORATION
Inventor: Xiaohui ZHAN , Ilmar HEIN , Ruoqiao ZHANG
CPC classification number: A61B6/4241 , A61B6/032 , A61B6/4233 , G01T1/247 , G01T1/17 , G01T1/2985
Abstract: A photon counting detector (PCD) apparatus includes a PCD array including a plurality of micro-pixels positioned in at least one of a channel direction and a row direction; and processing circuitry configured to: receive signals from each of the plurality of micro-pixels; configure the PCD array to include (a) a first micro-pixel area including a first group of plural micro-pixels of the plurality of micro-pixels and (b) a second micro-pixel area including a second group of plural micro-pixels of the plurality of micro-pixels, such that a portion of the first and second groups of plural micro-pixels overlap between the first and second groups; bin the signals from the first group of plural micro-pixels into a first virtual bin value; and bin the signals from the second group of plural micro-pixels into a second virtual bin value.
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8.
公开(公告)号:US20230083935A1
公开(公告)日:2023-03-16
申请号:US17469310
申请日:2021-09-08
Applicant: CANON MEDICAL SYSTEMS CORPORATION
Inventor: Yujie LU , Ilmar HEIN , Zhou YU
Abstract: An apparatus and method to obtain input projection data based on radiation detected at a plurality of detector elements, reconstruct plural uncorrected images in response to applying a reconstruction algorithm to the input projection data, segment the plural uncorrected images into two or more types of material-component images by applying a deep learning segmentation network, generate output projection data corresponding to the two or more types of material-component images based on a forward projection, generate corrected multi material-decomposed projection data based on the generated output projection data corresponding to the two or more types of material-component images, and reconstruct the multi material-component images from the corrected multi material-decomposed projection data to generate one or more corrected images. In some embodiments, the plural uncorrected images are segmented into three or more types of material-component images by applying a deep learning segmentation network and beam hardening correction is performed for the three or more materials.
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9.
公开(公告)号:US20220233162A1
公开(公告)日:2022-07-28
申请号:US17156089
申请日:2021-01-22
Applicant: CANON MEDICAL SYSTEMS CORPORATION
Inventor: Xiaohui ZHAN , Xiaofeng NIU , Ilmar HEIN
Abstract: A method and a system for providing calibration for a polychromatic photon counting detector forward counting model. Measurements with multiple materials and known path lengths are used to calibrate the photon counting detector counting response of the forward model. The flux independent weighted bin response function is estimated using the expectation maximization method, and then used to estimate the pileup correction terms at plural tube voltage settings for each detector pixel. The beam hardening corrections are then applied to the measured projection data sinogram, and the corrected sinogram is reconstructed to the counting image at the selected single energy.
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公开(公告)号:US20210012543A1
公开(公告)日:2021-01-14
申请号:US16509408
申请日:2019-07-11
Applicant: Canon Medical Systems Corporation
Inventor: Ilmar HEIN , Zhou YU , Ting XIA
Abstract: A method and apparatus are provided that use deep learning (DL) networks to reduce noise and artifacts in reconstructed computed tomography (CT), positron emission tomography (PET), and magnetic resonance imaging (MRI) images. DL networks are used in both the sinogram and image domains. In each domain, a detection network is used to (i) determine if particular types of artifacts are exhibited (e.g., beam-hardening artifact, ring, motion, metal, photon-starvation, windmill, zebra, partial-volume, cupping, truncation, streak artifact, and/or shadowing artifacts), (ii) determine whether the detected artifact can be corrected through a changed scan protocol or image-processing techniques, and (iii) determine whether the detected artifacts are fatal, in which case the scan is stopped short of completion. When the artifacts can be corrected, corrective measures are taken through a changed scan protocol or through image processing to reduce the artifacts (e.g., convolutional neural network can be trained to perform the image processing).
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