MODEL BASED SCATTER CORRECTION IN PET

描述：(改编自摘要)这是一项建议 并测试适合应用于3-D的康普顿散射校正 (SEPTA OUT)PET成像。去除SETA可通过以下方式提高扫描仪灵敏度 4.8倍，但也会使散射事件增加约4.8倍 三。敏感度的提高可以带来剂量的好处 减少，更快的成像，或降噪，但首先是必要的 有一个准确的散射修正。这项研究的目标是 提出了一种基于物理模型的三维PET散射校正算法 同时使用传输和发射图像的原理，以及理论 用康普顿散射计算单次散射的个数 投影中的光子。这约占检测到的73% 零星的巧合。在上一个资助期内，基于模型 制定了精确度在12%以内的校正公式，可以 在当前工作站上计算不到6分钟，这仅是 重建整个3-D集所需时间的8%。这个 调查人员建议进一步开发该算法，以包括 探测器效率归一化、卷积校正 散射体，以及对来自外部活动的散射体的校正 视场以及薄隔膜模型。算法将是 使用SIMSET蒙特卡罗代码、幻影成像和人类进行评估 学习。样品的均匀性、对比度恢复和定量准确度 区域估计数将作为验证措施。被测试的人 算法及其文档将提供给其他 调查人员。

DESCRIPTION:(Adapted from the abstract) This is a proposal to develop and test a Compton scatter correction suitable for application to 3-D (septa out) PET imaging.Septa removal increases scanner sensitivity by a factor of 4.8, but also increases scatter events about a factor of three. The increased sensitivity can result in benefits of dose reduction, faster imaging, or noise reduction, but first it is necessary to have an accurate scatter correction. The goal of this research is to develop a scatter correction algorithm for 3-D PET based on physical principles using both transmission and emission images, and the theory of Compton scattering to calculate the number of single scattered photons in a projection.This accounts for about 73% of the detected scattered coincidences. During the previous funding period model- based corrections were formulated which were accurate to within 12% and could be computed on a current workstation in under 6 minutes, which is only 8% of the time required to reconstruct the whole 3-D set. The investigators propose to further develop the algorithm to include detector efficiency normalization, convolutional correction for multiple scatters, and correction for scatter originating from activity outside the field of view as well as a thin-septa model. The algorithm will be evaluated using the SIMSET Monte Carlo code, phantom imaging, and human studies. Uniformity, contrast recovery and quantitative accuracy of regional estimates will serve as validation measures. The tested algorithm and its documentation will be made available to other investigators.