公开(公告)号：US20230237638A1

公开(公告)日：2023-07-27

申请号：US17961365

申请日：2022-10-06

Applicant: The Regents of the University of California ,  Canon Medical Systems Corporation

Inventor： Tiantian LI ,  Zhaoheng XIE ,  Wenyuan QI ,  Li YANG ,  Evren ASMA ,  Jinyi QI

IPC: G06T7/00 ,  G06T5/00

CPC classification number: G06T7/0004 ,  G06T5/002 ,  G06T2207/10104 ,  G06T2207/10088 ,  G06T2207/10081 ,  G06T2207/20081 ,  G06T2207/20084

Abstract: A method, apparatus, and non-transitory computer-readable storage medium for image denoising whereby a deep image prior (DIP) neural network is trained to produce a denoised image by inputting the second medical image to the DIP neural network and combining a converging noise and an output of the DIP network during the training such that the converging noise combined with the output of the DIP network approximates the first medical image at the end of the training, wherein the output of the DIP network represents the denoised image.

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：US20200170605A1

公开(公告)日：2020-06-04

申请号：US16209551

申请日：2018-12-04

Applicant: CANON MEDICAL SYSTEMS CORPORATION

Inventor： Wenyuan QI ,  Chung Chan ,  Li Yang ,  Evren Asma

IPC: A61B6/00 ,  A61B6/03 ,  G01T1/29

Abstract: A method and apparatus is provided to correct for scatter in a positron emission tomography (PET) scanner, the scatter coming from both within and without a field of view (FOV) for true coincidences. For a region of interest (ROI), the outside-the-FOV scatter correction are based on attenuation maps and activity distributions estimated from short PET scans of extended regions adjacent to the ROI. Further, in a PET/CT scanner, these short PET scans can be accompanied by low-dose X-ray computed tomography (CT) scans in the extended regions. The use of short PET scans, rather than full PET scans, provides sufficient accuracy for outside-the-FOV scatter corrections with the advantages of a lower radiation dose (e.g., low-dose CT) and requiring less time. In the absence of low-dose CT scans, an atlas of attenuation maps or a joint-estimation method can be used to estimate the attenuation maps for the extended regions.