公开(公告)号：US20190192090A1

公开(公告)日：2019-06-27

申请号：US16232072

申请日：2018-12-26

Applicant: TSINGHUA UNIVERSITY ,  NUCTECH COMPANY LIMITED

Inventor： Liang Li ,  Zhiqiang Chen ,  Kejun Kang ,  Ziran Zhao ,  Li Zhang ,  Yuxiang Xing ,  Tiao Zhao ,  Jianmin Li ,  Bicheng Liu ,  Qian Yi

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

Abstract: The present disclosure provides a decomposition method based on basis material combination. In the present disclosure, a scanned object is divided into a plurality of regions, the basis material combinations used in each of the divided regions are different each other, and the scanned object is re-divided according to the re-determined equivalent atomic number of its each point until the change on decomposition coefficient meets certain conditions. Thereby, a decomposition method based on dynamic basis material combinations is realized, which reduces a decomposition error caused by improper selection of the basis material combination and improves the accuracy of the decomposition and substance identification of the multi-energy CT.

公开(公告)号：US09702832B2

公开(公告)日：2017-07-11

申请号：US14304848

申请日：2014-06-13

Applicant: NUCTECH COMPANY LIMITED

Inventor： Le Shen ,  Yuxiang Xing ,  Li Zhang ,  Zhiqiang Chen

IPC: A61B6/03 ,  G01N23/04 ,  A61B6/00 ,  G06T11/00

CPC classification number: G01N23/046 ,  A61B6/032 ,  A61B6/4085 ,  A61B6/4241 ,  A61B6/482 ,  A61B6/5205 ,  A61B6/5258 ,  G06T11/005 ,  G06T11/006 ,  G06T2211/408 ,  G06T2211/436

Abstract: Disclosed is a CT imaging method and system. The method includes: CT scanning an object with a dual-energy CT system to obtain a first complete set of projection data in a first scan mode, and to obtain a second incomplete set of projection data in a second scan mode; reconstructing a first attenuation coefficient image of the object from the first set of projection data, and extracting, from the first attenuation coefficient image, prior structure information of the object indicating edge intensity; and reconstructing a second attenuation coefficient image of the object from the second incomplete set of projection data using the extracted prior structure information as a constraint. With the method using the prior structure information of the imaged object as a constraint in reconstruction, it is possible to dramatically reduce an amount of data required for reconstruction, and achieve satisfactory effects even with ill-conditioned problems of limited-angle and inner reconstruction.

公开(公告)号：US09326743B2

公开(公告)日：2016-05-03

申请号：US14135023

申请日：2013-12-19

Applicant: TSINGHUA UNIVERSITY ,  NUCTECH COMPANY LIMITED

Inventor： Le Shen ,  Yuxiang Xing ,  Qi Shen ,  Meng Cao ,  Li Zhang ,  Zhiqiang Chen

IPC: A61B6/00 ,  G01N23/04 ,  G01V5/00 ,  A61B6/02 ,  A61B5/00

CPC classification number: A61B6/482 ,  A61B5/4869 ,  A61B6/027 ,  A61B6/5205 ,  A61B6/54 ,  G01N23/046 ,  G01N2223/419 ,  G01V5/005

Abstract: The present invention relates to a Computed Tomography (CT) imaging system, in particular to a multi-energy CT imaging system and imaging method.

Abstract translation: 本发明涉及一种计算机断层成像（CT）成像系统，特别涉及一种多能CT成像系统和成像方法。

公开(公告)号：US10896527B2

公开(公告)日：2021-01-19

申请号：US16045303

申请日：2018-07-25

Applicant: Tsinghua University ,  NUCTECH COMPANY LIMITED

Inventor： Yuxiang Xing ,  Li Zhang ,  Jianmin Li ,  Zhiqiang Chen ,  Jianping Gu

IPC: G06T11/00 ,  G06N5/04 ,  G06N3/04 ,  G06T5/00 ,  G06N3/08

Abstract: A method and device for reconstructing a CT image and a storage medium are disclosed. CT scanning is performed on an object to be inspected to obtain projection data. The projection data is processed using a first convolutional neural network to obtain processed projection data. The first convolutional neural network comprises a plurality of convolutional layers. A back-projection operation is performed on the processed projection data to obtain a reconstructed image.

公开(公告)号：US10724969B2

公开(公告)日：2020-07-28

申请号：US16175796

申请日：2018-10-30

Applicant: Tsinghua University ,  Nuctech Company Limited

Inventor： Yuxiang Xing ,  Xiaoyue Guo ,  Zhi Deng ,  Le Shen ,  Li Zhang ,  Zhiqiang Chen ,  Liang Li

IPC: G01N23/04 ,  A61B6/00 ,  G01N23/046 ,  A61B6/03

Abstract: An X-ray detection method and an X-ray detector are provided. The X-ray detection method according to embodiments of the present disclosure includes: dividing an energy range of photons emitted by an X-ray source into a number N of energy windows, where N is an integer greater than 0; obtaining a weighting factor for each of the number N of energy windows based on linear attenuation coefficients of a substance of interest and a background substance of an imaging target; obtaining a weighting factor matrix for M output channels of an X-ray detector based on the weighting factor for each of the number N of energy windows, where M is an integer greater than 0; and obtaining output results of the M output channels based on the weighting factor matrix and numbers of photons having an energy range falling into individual energy windows of the number N of energy windows.

公开(公告)号：US10448904B2

公开(公告)日：2019-10-22

申请号：US16232072

申请日：2018-12-26

Applicant: TSINGHUA UNIVERSITY ,  NUCTECH COMPANY LIMITED

Inventor： Liang Li ,  Zhiqiang Chen ,  Kejun Kang ,  Ziran Zhao ,  Li Zhang ,  Yuxiang Xing ,  Tiao Zhao ,  Jianmin Li ,  Bicheng Liu ,  Qian Yi

IPC: G06K9/00 ,  A61B6/03 ,  G06T11/00 ,  A61B6/00

Abstract: The present disclosure provides a decomposition method based on basis material combination. In the present disclosure, a scanned object is divided into a plurality of regions, the basis material combinations used in each of the divided regions are different each other, and the scanned object is re-divided according to the re-determined equivalent atomic number of its each point until the change on decomposition coefficient meets certain conditions. Thereby, a decomposition method based on dynamic basis material combinations is realized, which reduces a decomposition error caused by improper selection of the basis material combination and improves the accuracy of the decomposition and substance identification of the multi-energy CT.

公开(公告)号：US10302578B2

公开(公告)日：2019-05-28

申请号：US15494884

申请日：2017-04-24

Applicant: Tsinghua University ,  Nuctech Company Limited

Inventor： Liang Li ,  Zhiqiang Chen ,  Kejun Kang ,  Li Zhang ,  Ziran Zhao ,  Yuxiang Xing ,  Jianmin Li ,  Yulan Li ,  Tiao Zhao

IPC: G01N23/046 ,  G01N23/087

Abstract: Methods and system for decomposing a high-energy dual-energy X-ray CT material are disclosed. In the method, two types of effect such as Compton effect and electron pairing effect which dominates are reserved and the influence of the other effect such a photoelectric effect is removed so as to improve the accuracy of the material decomposition. The unique advantage of the present disclosure is to effectively remove the error of the calculated atomic number Z due to directly selecting two effects during processes of material decomposition in the conventional dual-energy CT method. This may greatly improve the accuracy of dual-energy CT identification of the material, and it is important to improve the conventional dual-use CT imaging system applications, such as clinical therapy, security inspection, industrial non-destructive testing, customs anti-smuggling and other fields.

公开(公告)号：US20180038970A1

公开(公告)日：2018-02-08

申请号：US15597003

申请日：2017-05-16

Applicant: Tsinghua University ,  NUCTECH COMPANY LIMITED

Inventor： Liang Li ,  Zhiqiang Chen ,  Li Zhang ,  Ziran Zhao ,  Yuxiang Xing ,  Kejun Kang ,  Lan Zhang ,  Ruizhe Li

IPC: G01T7/00 ,  G01N23/223

CPC classification number: G01T7/005 ,  G01N23/223 ,  G01N2223/076 ,  G01N2223/303

Abstract: A method and apparatus for reconstructing an incident energy spectrum for a detector are disclosed. In this method, an object to be inspected is illuminated with rays, and then rays transmitted through the object to be inspected are received by the detector to convert the received rays into data of a detected energy spectrum. The incident energy spectrum for the detector is reconstructed based on the data of the energy spectrum using a statistical iterative algorithm with a pre-established detector response function. With the above solution of the embodiments, the incident energy spectrum for the detector can be more accurately acquired, thereby reducing a distortion of the incident energy spectrum caused by the detector.

公开(公告)号：US20150356755A1

公开(公告)日：2015-12-10

申请号：US14758795

申请日：2013-10-31

Applicant: NUCTECH COMPANY LIMITED ,  TSINGHUA UNIVERSITY

Inventor： Le Shen ,  Yuxiang Xing ,  Yuanji Li ,  Chuqing Feng ,  Li Zhang ,  Zhiqiang Chen

IPC: G06T11/00 ,  A61B6/03 ,  A61B6/00 ,  G06T5/50

CPC classification number: G06T11/005 ,  A61B6/032 ,  A61B6/4241 ,  A61B6/4266 ,  A61B6/482 ,  A61B6/5205 ,  G01N23/046 ,  G01N2223/419 ,  G01T1/2985 ,  G06T5/50 ,  G06T2207/10081 ,  G06T2207/20182

Abstract: CT imaging systems and methods thereof are disclosed. A common CT scanning is performed on an object to obtain a common CT imaging. An area of interest is determined from the image. A CT scanning is performed on the area of interest under a plurality of energy windows by a photon counter detector. A high resolution image of the area of interest is reconstructed. The discrimination of energy spectrum is higher and the result so obtained is more stable by using a photon counter detector to collect photon count projection data of a plurality of energy windows and thus it may be decomposed into a plurality of basis functions.

Abstract translation: 公开了CT成像系统及其方法。 对物体执行常见的CT扫描以获得常见的CT成像。 根据图像确定感兴趣的区域。 通过光子计数器检测器在多个能量窗口下对感兴趣的区域进行CT扫描。 重建感兴趣区域的高分辨率图像。 通过使用光子计数器检测器来收集多个能量窗口的光子计数投影数据，能量谱的辨别较高，得到的结果更加稳定，因此可将其分解为多个基本函数。

公开(公告)号：US20150332486A1

公开(公告)日：2015-11-19

申请号：US14708866

申请日：2015-05-11

Applicant: Nuctech Company Limited ,  Tsinghua University

Inventor： Li Zhang ,  Zhiqiang Chen ,  Le Shen ,  Yuxiang Xing ,  Xin Jin ,  Qingping Huang

IPC: G06T11/00 ,  G06T7/00 ,  A61B6/00 ,  A61B6/03 ,  A61B6/02

CPC classification number: G06T11/006 ,  A61B6/027 ,  A61B6/032 ,  A61B6/4085 ,  A61B6/4266 ,  A61B6/5205 ,  G06T7/0012 ,  G06T2207/10081 ,  G06T2207/30004 ,  G06T2211/421

Abstract: The present disclosure discloses a spiral CT system and a reconstruction method thereof. In some embodiments, it is proposed that data missing due to a large pitch is compensated by weighting the complementary projection data of the projection data obtained using the spiral CT system. After the data is complemented, the projection data is rebinned as cone parallel beam data, cone-angle cosine weighting and one-dimensional filtering are implemented on the rebinned data, and parallel beam back projection is finally implemented on the filtered data, to obtain the reconstructed images. In some embodiments, with the above method, the speed of the belt can be increased by more than one time in a case that the existing area of the detectors and the existing speed of the slip ring are unchanged, thereby improving the pass rate of the luggage and maintaining the quality of the reconstructed images unchanged.

Abstract translation: 本公开公开了一种螺旋CT系统及其重建方法。 在一些实施例中，提出通过对使用螺旋CT系统获得的投影数据的互补投影数据进行加权来补偿由于大音调而丢失的数据。 数据补充后，将投影数据重新设置为锥形平行光束数据，对重定位数据进行锥角余弦加权和一维滤波，最后在滤波数据上实现平行光束反投影，获得 重建图像。 在一些实施例中，利用上述方法，在检测器的现有区域和滑环的现有速度不变的情况下，带的速度可以增加多于一次，从而提高了传感器的通过率 行李保持重建图像的质量不变。