Time-of-flight positron emission tomography using Cerenkov luminescence in bismuth germanate

使用锗酸铋中的切伦科夫发光进行飞行时间正电子发射断层扫描

• 批准号: 10376047
• 负责人: Sun Il Kwon
• 金额: $ 36.9万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10376047
• 关键词: Area; Binding; Biomedical Research; Bismuth; Brain; Breast; Dedications; Detection; Dose; Electronics; Electrons; Event; Gamma Rays; Generations; Goals; Healthcare; Human; Image; Imaging Techniques; LSO crystal; Light; Measures; Methods; Noise; Optics; Outcome; Output; Performance; Photons; Positron-Emission Tomography; Process; Production; Property; Radioactivity; Resolution; Shapes; Signal Transduction; Silicon; Surface; Syncope; System; Technology; Thick; Time; Visualization; cost; design; detector; improved; luminescence; molecular diagnostics; novel; photomultiplier; photon-counting detector; translational medicine

SUMMARY Positron emission tomography (PET) is widely used as a diagnostic molecular imaging technique and clearly has had a significant impact on human healthcare. There have been significant improvements in PET technology by employing time-of-flight (TOF) capability that measures the difference in arrival time of the two 511 keV gamma annihilation rays. This TOF information spatially constrains the origin of the event, leading to improved image quality due to the increased signal-to-noise ratio (SNR) and effective sensitivity in the PET scan. The scintillator bismuth germanate (BGO), however, has several better properties for PET applications than L(Y)SO, such as higher stopping power and higher photo-electric fraction. BGO also has no background activity and can be produced at lower cost than L(Y)SO. However, a major drawback of BGO is the poor coincidence timing resolution originating from the moderate light yield and slow decay time of scintillation photon production. Therefore, BGO has not been considered for use in current generation TOF PET scanners. Theoretically, when a 511keV gamma ray interacts in a scintillator, a small number of optical Cerenkov photons are produced promptly by energetic electrons released by photoelectric or Compton interactions. The Cerenkov photons are produced within an extremely short time frame and earlier than scintillation photons, Thus the Cerenkov photons should provide better timing information for PET. Interestingly, BGO has properties that lead to it producing more Cerenkov photons than other scintillators. Recently, we showed, for the first time, the influence of prompt Cerenkov photons on the timing properties of BGO using latest generation silicon photomultipliers (SiPMs) developed by our partner FBK. Thus, our proposed concept for BGO is that Cerenkov photons are used to obtain prompt timing information while scintillation photons provide essential energy information for PET. The major goals of this proposal are i) to improve coincidence timing resolution of BGO by detecting more Cerenkov photons for TOF PET applications, ii) to develop signal reducing methods and read-out electronics for signals generated by both Cerenkov and scintillation photons, and iii) to finally develop and evaluate the first practical BGO-based TOF PET detector modules, which have 5 × 5 cm2 cross-sectional area and a coincidence timing resolution of ≤300 ps FWHM. If successful, this proposal forms the basis for developing novel BGO-based TOF PET scanners with higher sensitivity and lower cost than current PET scanners.

概括 正电子发射断层扫描（PET）被广泛用作诊断分子成像技术，并且清楚地使用 对人类医疗保健产生了重大影响。宠物技术已经有了重大改进 通过使用飞行时间（TOF）功能来衡量两个511 KEV的到达时间差异 伽玛歼灭射线。此TOF信息在空间上限制了事件的起源，从而改善了 图像质量由于信噪比增加（SNR）和PET扫描中的有效灵敏度而引起的。 但是 l（y）如此，例如更高的停止功率和更高的光电部分。 BGO也没有背景活动 并且可以以低（y）的价格低成本生产。但是，BGO的主要缺点是不良的巧合 定时分辨率源自现代光产量和闪烁光子产生的缓慢衰减时间。 因此，BGO尚未考虑用于当前一代TOF PET扫描仪。 理论上，当511kev伽玛射线在闪烁体中相互作用时，少数光学的cerenkov照片 由光电或康普顿相互作用发布的能量电子迅速产生。塞伦科夫 Photosons是在极短的时间范围内生产的，并且比闪烁照片更早，这就是 Cerenkov照片应为PET提供更好的定时信息。有趣的是，BGO具有领导的特性 与其他闪烁体相比，它会产生更多的Cerenkov照片。 最近，我们首次展示了迅速的Cerenkov照片对定时属性的影响 BGO使用我们的合作伙伴FBK开发的最新一代硅光电塑料（SIPM）。那是我们提出的 BGO的概念是，Cerenkov照片用于获取迅速的定时信息，而闪烁照片 为宠物提供基本能源信息。该提案的主要目标是我）提高巧合 通过检测更多用于TOF PET应用的Cerenkov照片来解决BGO，ii）开发信号 减少Cerenkov和闪烁照片产生的信号的方法和读出电子设备， iii）最终开发和评估第一个实用的基于BGO的TOF PET检测器模块，该模块具有5个 ×5 cm2横截面区域和巧合计时分辨率为≤300ps fwhm。如果成功，这个建议 构成了开发基于BGO的新型TOF PET扫描仪的基础，其灵敏度较高，成本低于 当前的宠物扫描仪。