DEVELOPMENT OF AN ULTRA HIGH COUNT RATE GAMMA CAMERA

描述(改编自申请者摘要)：本项目的目标 就是开发提高伽马成像能力的技术 用于平面、SPECT和PET应用的相机。虽然现在的伽马相机 足以对低诊断剂量的单光子示踪剂进行成像， 由于NaI(Tl)探测器中的信号堆积，它们的低计数率能力 Gamma时会产生图像瑕疵、计数损失和较低的图像质量 流量很高。这些情况包括：(A)正电子示踪成像， 需要将注射剂量减少80%-90%，以避免堆积，(B) 大剂量放射性核素治疗剂量学，不能成像 由于缺乏快速照相机，(C)动态首过心脏成像， (D)使用寿命极短的示踪剂以减少辐射剂量和 增加患者吞吐量，以及(E)使用更大的NaI(TL)探测器以 减少全身扫描时间。该项目建议开发一种连环相撞 用于伽马相机的预防电子方法(PPE)，其可以 将最大计数率提高25-50倍。这样做的具体目的是 建议是(I)优化拟议的PPE电子设备；(Ii)建造一个 移动实验摄像平台。这将有助于发展 电子设备，并允许在未来对人类应用进行测试； 为了在实验相机平台上开发两个PPE实现， 单区和多区。第二种设计将摄像机一分为四 带有4个PPE电路的区域，以进一步提高计数率。(Iv)至 评估伽马相机的成像性能作为以下各项的函数 计数-以幻影为单位的比率。该项目可能会使成本更低的伽马相机 图像正电子追踪器，没有专门的250万美元的PET摄像头，并且有 与目前的伽马相机自适应相比，图像质量有了很大的改善 可能会注射10倍以上的剂量。放射性核素治疗的直接成像 (RNT)将允许更准确的剂量计算并改进 对RNT的理解。它还将允许同时收购 具有一个摄像头和双同位素的传输和发射数据 定量SPECT，衰减校正误差较小。

DESCRIPTION (Adapted from Applicant's Abstract): The goal of this project is to develop the technology to improve the imaging capability of gamma cameras for planar, SPECT and PET application. While present gamma cameras are adequate for imaging low diagnostic doses of single-photon tracers, their low count-rate capability due to signal pileup in the NaI(Tl) detector produces image artifacts, count loss, and lower image quality when gamma flux is high. These situations include (a) positron tracer imaging, which requires an 80-90% reduction in injected dose to avoid pileups, (b) high-dose radionuclide therapy for dosimetry, which can not be imaged because of the lack of fast cameras, (c) dynamic first-pass cardiac imaging, (d) the use of very short-lived tracers to reduce radiation dose and increase patient throughput, and (e) the use of larger NaI(Tl) detectors to reduce whole-body scanning time. This project proposes developing a pileup prevention electronic method (PPE) for use on gamma cameras, which may increase the maximum count rates by 25-50 times. The specific aims of this proposal are (I) to optimize the proposed PPE electronics; (II) to build a mobile experimental camera platform. It would facilitate the development of the electronics and allow testing of human applications in the future; (III) to develop two PPE implementations on the experimental camera platform, a single-zone and a multi-zone. The second design splits the camera into 4 zones with 4 PPE circuits to increase the count-rates even more. (IV) to evaluate the imaging performance of the gamma camera as a function of count-rates in phantoms. This project may allow lower cost gamma cameras to image positron tracers without a dedicated $2.5 million PET camera, and with a much improved image quality over the present gamma camera adaptation since a 10x higher dose may be injected. Direct imaging of radionuclide therapy (RNT) would allow more accurate dosimetry calculations and improve the understanding of RNT. It would also allow simultaneous acquisition of transmission and emission data with one camera head and dual isotopes for quantitative SPECT, with less errors in attenuation correction.