STATISTICAL METHODS FOR IMAGE RECONSTRUCTION IN ECT

描述(改编自申请者摘要)：本报告的总体目标 研究是开发、实施、分析和评估新的统计数据 发射计算中的层析图像重建方法 体层摄影术。提出的方法改进了传统的滤波方法 反投影重建方法，以及非正则化迭代 最近商业化的方法(用于SPECT)和 有各种缺点，包括收敛速度慢、噪音大 随着迭代而增加的伪影，以及不均匀的空间分辨率。 这项建议采取了全面的方法来改善以下几点 统计重建方法的相互关联的组成部分：发展 更准确且对模型误差更稳健的统计模型， 以及开发快速全局收敛的迭代算法，以求最大化 统计目标函数。我们将特别强调 研究重建衰减图的改进方法 传输测量，因为常规衰减中的误差 校正方法对噪声有很大影响。 重建发射图像。这项工作将侧重于迭代 适用于大型三维数据集的并行算法 使用多处理器架构的计算。虽然方法论 应该普遍适用于正电子发射计算机断层扫描和SPECT，研究人员将 专注于胸部和腹部的应用，即PET肿瘤学 显像和SPECT心脏显像。由此带来的图像质量的提高 来自适当的统计建模和较低噪声的衰减校正 在这些应用中应该具有特别重要的临床价值。 建议的注射后PET透射率扫描统计方法 将显著提高延迟FDG PET的临床应用 扫描。

DESCRIPTION (Adapted from Applicant's Abstract): The overall goal of this research is to develop, implement, analyze, and evaluate new statistical methods for tomographic image reconstruction in emission computed tomography. The proposed methods improve on the conventional filtered backprojection reconstruction method, as well as the unregularized iterative methods that have recently become available commercially (for SPECT) and suffer from a variety of disadvantages, including slow convergence, noise artifacts that increase with iteration, and nonuniform spatial resolution. This proposal takes a holistic approach to improving the following interconnected components of statistical reconstruction methods: developing statistical models that are more accurate and are robust to model errors, and developing fast globally convergent iterative algorithms for maximizing the statistical objective function. Particular emphasis will be placed on investigating improved methods for reconstructing attenuation maps from transmission measurements, since errors in conventional attenuation correction methods contribute very significantly to the noise in the reconstructed emission image. This effort will focus on iterative algorithms that are suitable for large 3-D data sets by applying parallel computing using multiprocessor architectures. Although the methodology should be generally applicable in PET and SPECT, the investigators will focus on applications in the thorax and abdomen, namely PET oncologic imaging and SPECT cardiac imaging. The improved image quality that results from proper statistical modeling and less noisy attenuation correction should be of particularly significant clinical value in those applications. The proposed statistical methods for post-injection PET transmission scans will significantly improve the clinical utility of PET with delayed FDG scans.