PET/SPECT同机同时成像方法研究

PET and SPECT are key techniques in molecular imaging. This study aims at developing integrated simultaneous PET/SPECT imaging techniques, correlating the dual-modality images in both space and time domain, and providing novel imaging diagnostic information. In preliminary studies, we have proven the feasibility of performing SPECT photon detection with PET detector.In this study, we plan to implment simultaneous coincidence PET imaging and single-photon SPECT imaging with LYSO detector ring and pinhole collimator insert. We will present a collimator design with theoretical analysis and simulation, and build up a simultaneous imaging platform; We will optimize the detector's performance for dual-energy PET and SPECT photon detection; We will establish a physical model of the simultaneous imaging process, develop a joint PET/SPECT iterative image reconstruction algorithm, and develop system calibration and data correction methods; We will conduct phantom and animal imaging studies and present simultaneous PET/SPECT images. The success of this study will improve the performance and feasibility of PET/SPECT simultaneous imaging techniques in clinical applications, and expand multi-modality imaging technologies in molecular imaging research.

PET和SPECT是分子影像学研究的关键技术。本研究旨在发展PET/SPECT同机同时成像方法，使双模态融合图像在空间和时间上均具有相关性，为影像诊断提供新的信息。我们已经在前期研究中验证了在PET探测器上进行SPECT光子测量的可行性。本研究拟基于LYSO环探测器和嵌入式针孔准直器，同时实现符合PET成像和单光子SPECT成像。将通过理论分析和模拟设计准直器，搭建同时成像装置；优化探测器性能以适应双能段PET和SPECT光子探测；对同时成像过程进行物理建模，开发联合PET/SPECT图像迭代重建算法；研究系统刻度和数据校正方法；在实验装置上进行模型和动物成像实验，获得同时PET/SPECT融合图像。本课题的成功研究将提高PET/SPECT同时成像技术的成像性能和临床实用性，丰富分子影像学研究的多模态融合成像手段。

本研究旨在发展PET/SPECT同机同时成像方法，使双模态融合图像在空间和时间上均具有相关性，为影像诊断提供新的信息。项目就PET/SPECT同机同时成像中的多针孔准直器设计、系统精确建模方法、PET和SPECT图像重建算法、向下散射校正方法开展了深入研究，成功试制了PET/SPECT同时成像实验装置，获得了PET/SPECT同时成像的模型图像和动物图像结果，PET和SPECT的空间分辨率均达到1.35 mm，并成功进行了技术成果转移和开展临床科研应用。本项目的研究成果是首次实现PET符合模式/SPECT单光子模式的同时成像，为多模态融合医学影像技术增添了新的成像模式，使得PET和SPECT的核素库可以同时在一次成像过程中得到应用。本项目的研究成果经过临床应用推广，有望大大扩展核医学影像用于临床诊断和科学研究的范畴，成为核医学影像技术发展的新方向。