SIMULTANEOUS X-RAY AND EMISSION COMPUTED TOMOGRAPHY

描述（改编自申请人的摘要）： 这项工作是为了提供执行X射线透射CT的能力 几乎与PET成像同时成像。 这将改善 数据进行衰减校正，并将大大减少什么一直是一个 PET重建中的主要误差来源。 的质量是否 透射CT数据高，重建图像将作为指导 用于精确确定放射性示踪剂摄取的解剖部位。 另外，重建的图像可以用作精确测量的指南。 确定放射性示踪剂摄取的解剖部位。 这些解剖图 是一个非常有用的辅助肿瘤图像采集使用PET在 与18FDG结合。 重点将放在制定低成本办法上; 具体地，使用低功率X射线源的锥形束扫描， 将研究与非晶硅成像探测器的结合。 非晶硅探测器阵列是最大的像素化成像设备 目前建成。 它们基于与过去相同的技术， 制造有源矩阵平板显示器。 具体目标是：（1）评估 并优化X射线非晶硅成像阵列的性能 透射CT; 2）实施适当的锥形束扫描， 重建技术; 3）开发用于估计PET衰减的方法 X射线CT数据的校正系数，特别强调最小化 必要的X射线剂量。 本项目期间的目标是 证明这一概念的可行性，并开发和验证 将用于设计组合X射线CT原型的技术 和PET系统。 成果 研究将应用于肿瘤学，并可能应用于 SPECT和放射治疗。

DESCRIPTION (Adapted from Applicant's Abstract): The long term objective of this work is to provide the capability of performing x-ray transmission CT imaging nearly simultaneously with PET imaging. This will provide improved data for attenuation correction and will greatly reduce what has been a primary source of error in PET reconstructions. If the quality of transmission CT data is high, reconstructed images will be useful as guides for precisely determining anatomic sites of radiotracer uptake. Additionally, reconstructed images may be useful as guides for precisely determining anatomic sites of radiotracer uptake. These anatomic maps would be an extremely useful adjunct to tumor images acquired using PET in conjunction with 18FDG. Emphasis will be on developing a low-cost approach; specifically, cone-beam scanning using a low-power x-ray source in conjunction with an amorphous silicon imaging detector will be investigated. Amorphous silicon detector arrays are the largest pixellated imaging devices presently built. They are based on the same technology as that used to create active-matrix flat-panel displays. The specific aims are 1) evaluate and optimize performance of amorphous silicon imaging arrays for x-ray transmission CT; 2) implement appropriate cone-beam scanning and reconstruction techniques; 3) develop methods for estimating PET attenuation correction factors from x-ray CT data with particular emphasis on minimizing necessary x-ray dose. The goal for the present project period is to demonstrate the feasibility of this concept and to develop and validate techniques that will be used to design a prototype of a combined x-ray CT and PET system in a subsequent project period. Results of this investigation will have application to oncology and may have application for both SPECT and radiotherapy treatment.