A new direction to achieve ultra-fast timing for positron emission tomography

实现正电子发射断层扫描超快定时的新方向

• 批准号: 9444922
• 负责人: CRAIG S LEVIN
• 金额: $ 64.71万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-30 至 2021-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9444922
• 关键词: Biodistribution; Charge; Clinic; Clinical Management; Clinical Research; Collection; Contrast Media; Crystallization; Detection; Disease; Disease Management; Dose; Elements; Enhancing Lesion; Event; Generations; Genetic Recombination; Goals; Image; Imagery; Imaging technology; Individual; Industry; Injectable; Ionizing radiation; Ions; Label; Lasers; Learning; Lesion; Light; Lutetium; Methods; Modernization; Molecular Profiling; Monitor; Nature; Noise; Operating System; Optics; Patients; Performance; Phase; Photons; Physiologic pulse; Positron; Positron-Emission Tomography; Predisposition; Process; Production; Property; Pump; Radiation; Radioisotopes; Refractive Indices; Research; Resolution; Roentgen Rays; Role; Scanning; Signal Transduction; Source; Speed; System; Telecommunications; Three-Dimensional Image; Time; Tracer; Width; Work; base; biological research; cost effective; design; detector; electric field; improved; ionization; migration; multidisciplinary; non-invasive imaging; novel; optical switch; photon-counting detector; scale up; temporal measurement; two-photon

PROJECT SUMMARY/ABSTRACT We propose to explore a new mechanism of ionizing radiation detection for positron emission tomography (PET) using the modulation of optical properties instead of scintillation, with the ultimate goal to achieve less than 10 picosecond (ps) annihilation photon pair coincidence time resolution, which is an order of magnitude better than possible with state-of-the-art scintillation based PET detectors. PET is a non-invasive imaging technology used every day throughout the world that enables visualization and quantification of the molecular signatures of disease in living subjects in the clinic as well as in biological research. A PET study comprises the collection of millions of annihilation photon pairs emitted from a positron-emitting radionuclide-labeled contrast agent injected into the patient. The two-photon hits are recorded by the system detectors and used to reconstruct a 3D image volume that represents the tracer biodistribution. If successful, the proposed < 10 ps coincidence time resolution would represent a tremendous paradigm shift for PET as it would drastically change the way a PET system operates. The resulting remarkable time-of-flight (ToF) capability will bring substantial signal amplification over existing systems. The enormous image signal-to-noise ratio (SNR) boost can be exploited to greatly enhance lesion detection, for example, for lesions with low contrast-to-background ratio; significantly reduce both patient injected dose and patient scan duration, potentially opening new clinical and research roles for which PET currently has no involvement at all; or pave the way for completely new PET system designs with greatly improved spatial resolution. In previous studies performed, we have shown that ionizing radiation can modulate optical properties, for example, the refractive index, of a detector material. We have found that the modulation signal amplitude is linearly dependent on both the event detection rate and average photon energy. In this project, we will work on further exploring mechanisms of optical property modulation to detect individual 511 keV photon interactions, and study the timing properties of this proposed detection concept with the goal to achieve < 10 ps coincidence time resolution. We first propose to achieve the detection of individual 511 keV photons using the mechanism of optical property modulation by developing novel methods to amplify the modulation signal and detection systems with significantly improved sensitivity. Then we plan to study the intrinsic timing properties of the optical property modulation process and explore methods to achieve < 10 ps coincidence time resolution for coincident 511 keV photon interactions. For the final aim, we will learn how to use this new mechanism of ionizing radiation detection to build a practical, “tileable” ToF-PET detection element. This is an exciting multi-disciplinary project that borrows ideas from the field of modern optics with a goal of enabling substantial improvements in ToF-PET performance to drive important advances in the study and clinical management of disease.

项目摘要/摘要 我们建议探索一种电离辐射检测的新机制 （PET）使用光学特性而不是闪烁的调制，其最终目标是实现更少的目标 超过10（ps）歼灭光子对重合时间分辨率，这是一个数量级 使用基于最新的基于闪烁的宠物探测器，胜于可能的好。 宠物是全世界每天使用的一种非侵入性成像技术，可实现可视化 诊所和生物学中生物受试者中疾病的分子特征的数量 研究。一项宠物研究包括从A发出的数百万歼灭光子对的集合 注射到患者的放射线标记的对比剂。记录了两次命中 由系统检测器，用于重建代表示踪剂生物分布的3D图像量。 如果成功，建议的<10 ps巧合时间分辨率将代表巨大的范式 宠物转移会大大改变宠物系统的运行方式。由此产生的非凡 飞行时间（TOF）功能将对现有系统带来大量的信号扩增。巨大 图像信号噪声比（SNR）的提升可以探索以大大增强病变检测，例如 对比度与背景比的病变；显着减少患者注射剂量和患者扫描 持续时间，有可能打开宠物目前根本没有参与的新临床和研究角色； 或为全新的宠物系统设计铺平了道路，并大大改进了空间分辨率。 在先前进行的研究中，我们表明电离辐射可以调节光学特性，因为 例如，检测器材料的折射率。我们发现调制信号放大器是 线性取决于事件检测率和平均光子能量。在这个项目中，我们将继续进行 进一步探索光质调制的机制，以检测单个511 keV光子相互作用， 并研究该提出的检测概念的定时属性，目的是实现<10 ps巧合 时间分辨率。我们首先建议使用该机制来检测单个511 KEV照片 通过开发新方法来放大调制信号和检测，光学性质调制 具有显着提高灵敏度的系统。然后，我们计划研究光学的内在时序特性 属性调制过程并探索实现<10 ps巧合时间分辨率的方法 511 KEV光子相互作用。对于最终目标，我们将学习如何使用这种电离辐射的新机制 检测以建立实用的“可易换” TOF-PET检测元件。这是一个令人兴奋的多学科项目 这借鉴了现代光学领域的想法，目的是实现TOF-PET的实质性改进 在研究和疾病临床管理中取得重要进展的绩效。