Novel optical detection methods for ultrafast positron emission tomography (PET)

项目摘要 正电子发射断层扫描（PET）是一种独特而强大的临床成像方式，可以检测 人体的分子和功能信息。然而，目前基于微膨胀的检测 机制在降低符合时间分辨率（CTR）方面提出了限制，这表明如何准确地 我们可以测量正电子在体内的发射点，从而测量信噪比（SNR）。一 提出了一种新的检测机制，通过直接 探测在闪烁光子发射之前发生的电离电荷。在10 ps CTR下， 预期临床优势包括以低得多的患者剂量进行实时成像。实现更少 在PET中的CTR超过10 ps时，Jeong博士将使用先进的光谱编码超快光学技术， 使用光的颜色来测量从该位置产生的湮灭光子的到达时间。在此以前， 在SLAC国家实验室进行了一项使用光谱编码的概念验证实验和模拟 加速器实验室在这个项目中，同样的技术将适用于湮灭光子， 具有更高的能量和更低的粒子数，如目标1所述。建立一个敏感的自由空间光学 实现<10 ps CTR的设置，其中从超快激光探针获得的光谱信息将被 比较湮灭光子的重合到达定时。在目标2中，并行地，基于光纤的 将开发探测模块用于探测激光束和电离轨迹的更强的空间重叠， 进一步实现有效的射束传输和高填充率。在目标3中，随着探测器模块的开发， 在目标1和2中，Jeong博士将演示10 ps CTR PET模块的动态成像性能 脑功能成像的研究Jeong博士将首先使用10 ps范围内的CTR值进行模拟 为了获得预期的图像质量，然后从具有固定位置的放射源收集动态数据， 这两个模块，毫秒帧，相关的人脑活动的时间尺度。从<10- ps CTR探测器将比来自两个相同时间帧的数据的SNR大约5倍 探测器的CTR为230 ps。拟议的项目是高度跨学科的，需要前沿的专业知识， 医学成像、超快光学、快速数据采集和PET图像重建。通过这个项目， 博士Jeong将在超快光学和医学成像领域接受进一步培训，从以前的 培训经验，成为一名独立调查员。上述研究领域的专家将提供建议， 帮助郑博士在斯坦福大学获得新技能，并提供出色的机构支持。K99/R00 培训计划，其中包括审计课程，赠款写作，职业发展和学生辅导，博士。 Jeong将能够获得关键技能，作为独立调查员蓬勃发展。

Project Summary Positron Emission Tomography (PET) is a unique and powerful clinical imaging modality that can detect molecular and functional information from the human body. However, the current scintillation-based detection mechanism poses constraints in reducing the coincidence time resolution (CTR), which indicates how accurately we can measure the point that positron was emitted from in the body, thus the signal-to-noise ratio (SNR). A novel detection mechanism is proposed to significantly reduce CTR, down to 10-picosecond (ps), by directly detecting the ionization charges, which occur before scintillation photon emission. With the 10-ps CTR, several clinical advantages are expected, including real-time imaging with a much lower patient dose. To achieve less than 10-ps CTR in PET, Dr. Jeong will use the advanced ultrafast optics technique of spectral encoding which uses colors of light to measure the arrival timing of the annihilation photons created from the position. Previously, a proof-of-concept experiment and simulation using the spectra encoding was performed at the SLAC national accelerator laboratory. For this project, the same technique will be tailored to the annihilation photons, which have higher energy and lower particle numbers, as described in Aim 1. Establish a sensitive free-space optical setup that achieves < 10ps CTR, where spectral information acquired from the ultrafast laser probes will be compared for the coincidence arrival timings of the annihilation photons. In Aim 2, in parallel, fiber-based detection modules will be developed for stronger spatial overlap of the probe laser beam and the ionization track, further enabling efficient beam delivery and high-packing fraction. In Aim 3, with the detector modules developed in Aims 1 and 2, Dr. Jeong will demonstrate the dynamic imaging performance of the 10-ps CTR PET modules toward functional brain imaging. Dr. Jeong will first perform simulations using the CTR values in the 10-ps range to obtain expected image quality then collect dynamic data from radioactive sources with fixed positions between the two modules, with milliseconds frames, relevant to human brain activity timescales. The SNR from the <10- ps CTR detectors will be ~5 times greater than the SNR of data taken with the same time frames from two detectors with 230-ps CTR. The proposed project is highly interdisciplinary, requiring forefront expertise in medical imaging, ultrafast optics, fast data acquisition, and image reconstruction for PET. Through this project, Dr. Jeong will be further trained in the areas of ultrafast optics and medical imaging, expanding from the previous training experience to become an independent investigator. Experts in the above research areas will advise and help Dr. Jeong to obtain new skill sets at Stanford, with excellent institutional support. Through this K99/R00 training plan which includes auditing classes, grant writing, career development, and student mentoring, Dr. Jeong will be able to obtain critical skills to flourish as an independent investigator.