GePEToS is a simulation framework developed over the last few years for assessing the instrumental performance of future PET scanners. It is based on Geant4, written in Object-Oriented C++ and runs on Linux platforms. The validity of GePEToS has been tested on the well-known Siemens ECAT EXACT HR+ camera. The results of two application examples are presented : the design optimization of a liquid Xe micro-PET camera dedicated to small animal imaging as well as the evaluation of the effect of a strong axial magnetic field on the image resolution of a Concorde P4 micro-PET camera.
Instituto de Física Corpuscular (IFIC)（粒子物理研究所）；Universitat de València（瓦伦西亚大学）；Donostia International Physics Center（圣塞巴斯蒂安国际物理中心）；Ikerbasque (Basque Foundation for Science)（伊克尔巴斯基（巴斯克科学基金会））
In the present ongoing study, we are proposing a prototype model for positron emission tomography detection technology by introduction of a new discriminatory window parameter. It can be a new generation PET detection technique. We introduced Polarization Measurement of the annihilation photons(generated from the annihilation of positron and electron) as an additional parameter in proposed prototype, to correlate annihilation photons of a particular annihilation event. The motivation behind this introduction is Quantum Entanglement relation between the two annihilation photons. These two oppos…
This paper describes three methods regarding the production of plastic scintillators. One method appears to be suitable for the manufacturing of plastic scintillator, revealing properties which fulfill the requirements of novel positron emission tomography scanners based on plastic scintillators. The key parameters of the manufacturing process are determined and discussed.
Super-resolution positron emission tomography by intensity modulation: Proof of concept
Huazhong University of Science and Technology（华中科技大学）；Wuhan National Laboratory for Optoelectronics（武汉国家实验室（光电））；University of Science and Technology of China（中国科学技术大学）；The University of Chicago（芝加哥大学）
We developed a positron emission tomography (PET) system for multiple-isotope imaging. Our PET system, named multiple-isotope PET (MI-PET), can distinguish between different tracer nuclides using coincidence measurement of prompt gamma-rays, which are emitted after positron emission. In MI-PET imaging with a pure positron emitter and prompt-gamma emitter, because of the imperfectness of prompt gamma-ray detection, an image for a pure positron emitter taken by MI-PET is superposed by a positron-γ emitter. Therefore, in order to make isolated images of the pure positron emitter, we developed ima…
A major strength of iterative algorithms used in positron emission tomography (PET) lies in their abilities to introduce precise models of the physics at play, which includes the statistical nature of the detection processes, and a detailed description of the radiation-matter interactions. The process of data acquisition by the imaging system is described in a system response model, or system response matrix (SRM). In PET, elements of this matrix correspond to a probability of a coincident pair of gamma emitted from a certain element of the imaged volume (voxel) to be detected by the apparatus…
One of the major challenges in design and developing of PET, scanners are the presence of inactive areas between the detector blocks which degrade the image spatial resolution and leads to streaking artifacts especially when we employ analytical image reconstruction. The aim of this study is to assess the feasibility of generating the gap-free PET image using the deep convolutional encoder-decoder in sinogram space. The gap-corrupted sinograms of simulated HRRT scanner, sinograms without gaps as ideal/ground truth and predicted sinograms owing to the implemented our deep-fill method were quant…
Purpose: The scattering phenomenon creates degrading effects in positron emission tomography (PET) and the corresponding events are rejected conventionally. We have proposed a mathematical model to retrace the original line of response of the single-scattered coincident events with the aim to incorporate such events in PET. Methods: We have devised a new Virtual extrapolation technique based on the concept of the probability density functions. Through which we transformed the original two-parameter list mode data for the coincident photon pairs to a one-parameter data set. The procedure of ran…
Positron emission tomography, like many other tomographic imaging modalities, relies on an image reconstruction step to produce cross-sectional images from projection data. Detection and localization of the back-to-back annihilation photons produced by positron-electron annihilation defines the trajectories of these photons, which when combined with tomographic reconstruction algorithms, permits recovery of the distribution of positron-emitting radionuclides. Here we produce cross-sectional images directly from the detected coincident annihilation photons, without using a reconstruction algori…
Renal Blood Flow Quantification During Standard Myocardial Perfusion Imaging with Rubidium-82 Positron Emission Tomography
University of British Columbia（不列颠哥伦比亚大学）；BC Cancer Research Institute（BC癌症研究所）；Perelman School of Medicine, University of Pennsylvania（宾夕法尼亚大学佩雷尔曼医学院）；Tawam Hospital/Johns Hopkins International and College of Medicine and Health Sciences Al Ain, Abu Dhabi, United Arab Emirates（塔瓦姆医院/约翰霍普金斯国际阿拉因医学院与卫生科学学院）；Hospital of the University of Pennsylvania（宾夕法尼亚大学医院）
研究探讨了在标准心肌灌注成像中使用 rubidium-82 PET 量化肾脏血流的可行性及生理有效性，发现肾脏 K1 值与肾功能密切相关，且在肾功能下降时显著降低。
Gamma-ray emission from special nuclear material (SNM) is relatively easy to shield from detection using modest amounts of high-Z material. In contrast, fast-neutrons are much more penetrating and can escape relatively thick high-Z shielding without losing significant energy. Furthermore, fast neutrons provide a clear and unambiguous signature of the presence of SNM with few competing natural background sources. The challenge of detecting fast neutrons is twofold. First, the neutron flux from SNM are only a fraction of the corresponding gamma-ray flux. Second, fast neutrons can be difficult to…
Positron Emission Tomography with quantum-entangled Compton events: first imaging results at clinically relevant activities
University of Zagreb（萨格勒布大学）；Institute for Medical Research and Occupational Health（医学研究与职业健康研究所）；University Hospital Centre Zagreb（萨格勒布大学医院中心）；School of Physics, University of Sydney（悉尼大学物理学院）；Instituto de Física Corpuscular (IFIC), CSIC-UV（粒子物理研究所（IFIC），西班牙国家研究委员会-瓦伦西亚大学）
Roadmap Towards Quantum Entanglement Positron Emission Tomography (QE-PET)
Institute of Physics, Jagiellonian University（雅盖隆大学物理研究所）；Center for Theranostics, Jagiellonian University（雅盖隆大学诊疗中心）；University of California Santa Cruz（加州大学圣克鲁兹分校）；Indian Institute of Technology Bombay（印度理工学院孟买分校）；The University of Tokyo（东京大学）；Institute for Medical Research and Occupational Health, Division of Radiation Protection（医学研究与职业健康研究所辐射防护部）；University of Sydney（悉尼大学）；University of Zagreb Faculty of Science, Department of Physics（萨格勒布大学理学院物理系）；ICTP South American Institute for Fundamental Research（ICTP南美基础研究所）；Universidade Federal de São Paulo（圣保罗联邦大学）；Instituto de Fisica Corpuscular (IFIC), CSIC-UV（粒子物理研究所（IFIC），西班牙国家研究委员会-瓦伦西亚大学）；University of Illinois Urbana–Champaign（伊利诺伊大学厄巴纳-香槟分校）；National Institutes for Quantum Science and Technology（国立量子科学技术研究院）；Institute of Science Tokyo（东京科学研究所）
A new approach to position reconstruction in TOFPET
蒙特卡罗模拟（MCS）是一种设计用于各种科学和技术应用的复杂装置的最先进的技术。采用基于GEANT（GEometry ANd Tracking）的MCS设计了一种简单的飞行时间正电子发射断层成像（TOFPET）。在MCS研究中，发展了一种新的正电子-电子湮灭点位置重建方法。仿真结果表明，这种技术可能是没有用的小动物成像相机，但可能是可行的诊断TOFPET相机。这种模拟技术的具体问题进行了讨论。
A novel Positron Emission Tomography system, based on plastic scintillators, is being developed by the J-PET collaboration. In this article we present the simulation results of the scatter fraction, representing one of the parameters crucial for background studies defined in the NEMA-NU-2-2012 norm. We elaborate an event selection methods allowing to suppress events in which gamma quanta were scattered in the phantom or underwent the multiple scattering in the detector. The estimated scatter fraction for the single-layer J-PET scanner varies from 37% to 53% depending on the applied energy thre…
J-PET Framework is an open-source software platform for data analysis, written in C++ and based on the ROOT package. It provides a common environment for implementation of reconstruction, calibration and filtering procedures, as well as for user-level analyses of Positron Emission Tomography data. The library contains a set of building blocks that can be combined by users with even little programming experience, into chains of processing tasks through a convenient, simple and well-documented API. The generic input-output interface allows processing the data from various sources: low-level data…
Integration of Spectral CT with PET and SPECT: Bringing Tissue Composition Information to Molecular Imaging
University of California Davis Health（加州大学戴维斯分校健康中心）；University College London（伦敦大学学院）；University of Pennsylvania（宾夕法尼亚大学）；University of Washington（华盛顿大学）
A Monte Carlo positronium decay source model with multiple annihilation channels in GATE
National Centre for Nuclear Research（国家核研究中心）；Jagiellonian University（雅盖隆大学）；INSA-Lyon, Université Claude Bernard Lyon 1（里昂国立应用科学学院，克劳德·贝尔纳里昂大学）；IT:U Interdisciplinary Transformation University（跨学科转型大学）；University of Vienna（维也纳大学）
GLOW-FDG: Generalized cancer LesiOn Whole-body segmentation model for $^{18}$F-FDG-PET/CT
Department of Radiation Oncology, University Hospital Zurich, University of Zurich, Zurich, Switzerland（苏黎世大学放射肿瘤科，苏黎世大学，苏黎世，瑞士）；Faculty of Medicine, University of Zurich, Zurich, Switzerland（苏黎世大学医学院，苏黎世，瑞士）；Division of Medical Image Computing, German Cancer Research Center (DKFZ), Heidelberg, Germany（德国癌症研究中心（DKFZ）医学图像计算部，海德堡，德国）；Department of Radiation Oncology, Institut de Cancérologie de Lorraine, Vandœuvre-lès-Nancy, France（洛林癌症研究所放射肿瘤科，法国 Vandœuvre-lès-Nancy）；Department of Thoracic Surgery, University Hospital Zurich, University of Zurich, Zurich, Switzerland（苏黎世大学胸外科科，苏黎世大学，苏黎世，瑞士）；ETOP IBCSG Partners Foundation, Bern, Switzerland（ETOP IBCSG合作伙伴基金会，瑞士伯恩）；Department of Nuclear Medicine, University Hospital Zurich, University of Zurich, Zurich, Switzerland（苏黎世大学核医学科，苏黎世大学，苏黎世，瑞士）
Erasmus+ Joint Program in Medical Imaging and Applications, University of Burgundy (France), UNICLAM (Italy) and University of Girona (Spain)（伊拉斯谟+医学影像与应用联合项目，勃艮第大学（法国）、UNICLAM（意大利）与赫罗纳大学（西班牙））
Positron Emission Tomography scan images are extensively used in radiotherapy planning, clinical diagnosis, assessment of growth and treatment of a tumor. These all rely on fidelity and speed of detection and delineation algorithm. Despite intensive research, segmentation remained a challenging problem due to the diverse image content, resolution, shape, and noise. This paper presents a fast positron emission tomography tumor segmentation method in which superpixels are extracted first from the input image. Principal component analysis is then applied on the superpixels and also on their avera…
The possibility to separate signals caused by 511 keV photons created in annihilation of electron-positron pairs and the so-called prompt photons from nuclei de- excitation is investigated. It could potentially be used to improve the quality of reconstructed images in the J-PET scanner in 2+1 photon tomography. Firstly, a research is conducted for several radioisotopes that decay via \b{eta}+ decay followed by de-excitation of an excited nucleus. Efficiency, purity and false positive rate are calculated for each isotope as a function of energy deposited threshold, with a hypothesis that signal…
Positron Emission Tomography (PET) is a widely-used imaging modality for medical research and clinical diagnosis. Here we demonstrate, through detailed experiments and simulations, an exploration of the benefits of exploiting the quantum entanglement of linear polarisation between the two positron annihilation photons utilised in PET. A new simulation, which includes the predicted influence of quantum entanglement on the interaction of MeV-scale photons with matter, is validated by comparison with experimental data from a cadmium zinc telluride (CZT) PET demonstrator apparatus. In addition, a …
PETALO (Positron Emission Tof Apparatus with Liquid xenOn) is a novel concept for positron emission tomography scanners, which uses liquid xenon as a scintillation medium and silicon photomultipliers as a readout. The large scintillation yield and the fast scintillation time of liquid xenon, as well as its scalability, makes it an excellent candidate for PET scanners with Time-of-Flight measurements, especially for total-body machines. A first prototype of PETALO is fully operating, devoted to demonstrate the potential of the concept, measuring the energy and time resolution and to test techni…
University Medical Center Utrecht（乌得勒支大学医学中心）；DKFZ German Cancer Research Center（德国癌症研究中心）；Heidelberg University（海德堡大学）
Recently, deep learning (DL)-based methods for the generation of synthetic computed tomography (sCT) have received significant research attention as an alternative to classical ones. We present here a systematic review of these methods by grouping them into three categories, according to their clinical applications: I) To replace CT in magnetic resonance (MR)-based treatment planning. II) Facilitate cone-beam computed tomography (CBCT)-based image-guided adaptive radiotherapy. III) Derive attenuation maps for the correction of positron emission tomography (PET). Appropriate database searching …
Emory University（埃默里大学）；Winship Cancer Institute, Emory University（埃默里大学温希普癌症研究所）
This paper reviewed the machine learning-based studies for quantitative positron emission tomography (PET). Specifically, we summarized the recent developments of machine learning-based methods in PET attenuation correction and low-count PET reconstruction by listing and comparing the proposed methods, study designs and reported performances of the current published studies with brief discussion on representative studies. The contributions and challenges among the reviewed studies were summarized and highlighted in the discussion part followed by.
Multibranch Generative Models for Multichannel Imaging with an Application to PET/CT Synergistic Reconstruction
Univ. Brest, LaTIM, INSERM, UMR 1101（布雷斯特大学、LaTIM研究所、法国国家健康与医学研究院、UMR 1101联合研究单位）；Nuclear Medicine Department, Poitiers University Hospital（普瓦捷大学医院核医学科）
We are investigating a prototype virtual pinhole positron emission tomography (VP-PET) system for small animal imaging applications. The PET detector modules were made up of 1.3 mm lutetium-yttrium oxyorthosilicate (LYSO) arrays, and the insert detectors consists of 0.6 mm pixelated Cadmium Zinc Telluride (CdZnTe). To validate the imaging experiment, we conducted a Monte Carlo simulation for the VP-PET system in Geant4 Application for Emission Tomography (GATE). For a point source of Na-22 with 0.5 mm diameter, the filtered back-projection (FBP) algorithm reconstructed PET image shows a resolu…
Recent tests of a single module of the Jagiellonian Positron Emission Tomography system (J-PET) consisting of 30 cm long plastic scintillator strips have proven its applicability for the detection of annihilation quanta (0.511 MeV) with a coincidence resolving time (CRT) of 0.266 ns. The achieved resolution is almost by a factor of two better with respect to the current TOF-PET detectors and it can still be improved since, as it is shown in this article, the intrinsic limit of time resolution for the determination of time of the interaction of 0.511 MeV gamma quanta in plastic scintillators is…
