全数字化PET能量获取方法研究
发布时间：2018-10-12 07:57
【摘要】：正电子发射断层成像（Positron Emission Tomography，简称PET）是一种非侵入式的造影方法，它通过探测活体内摄入放射性示踪剂的分布，无创、定动态地评估生物体内各种器官的代谢水平、生化反应、功能活动和灌注。作为当今核医学诊断和研究的尖端技术，PET在肿瘤、心血管、神经系统等的早期诊断、疗效评估以及基础研究等领域有着独特的应用价值。数字化的PET数据获得系统能够有效解决传统PET系统容易受环境干扰，校正困难的问题，同时引入数字信号处理技术带来的多种优势，是目前PET仪器设计的热点方向。 本文对一种新的全数字化脉冲获取能量获取方法——多电压阈值采样法(简称MVT)获取能量的关键因素进行了研究，包括噪声，基线，时间数字转换器（简称TDC）精度，以及阈值设置。提出了基于MVT的下降沿噪声处理方法，准确的获取脉冲的能量信息。并模拟仿真了实际硬件阈值个数与时间数字转换器的精度对MVT能量获取的影响。实现了基于MVT的基线校正算法。为实现MVT方法的PET采集系统奠定了基础。 在仿真的基础上，本文实现了一个基于MVT方法的闪烁能量脉冲获取系统，，该系统具有死时间短，全数字化，易于后期校正等优势。并以该系统为基础，对之前的仿真方法进行了验证，取得了初步的结果，为PET系统的全数字化能量获取打下了基础。 最后，本文以华中科技大学研制的数字化小动物PET系统为基础，充分运用闪烁脉冲特性和数字信号处理技术，研究并实现了闪烁脉冲的能量信息获取单元。在结合实际性能因素的考虑下，利用数字积分方法，获得了良好的能量性能，达到了预期的要求。
[Abstract]:Positron Emission Tomography (Positron Emission Tomography,) is a non-invasive imaging method that dynamically evaluates the metabolic level and biochemical reactions of various organs in living organisms by detecting the distribution of radioactive tracers in vivo. Functional activity and perfusion. As a cutting-edge technology in nuclear medicine diagnosis and research, PET has unique application value in early diagnosis, evaluation of curative effect and basic research in tumor, cardiovascular, nervous system and so on. The digital PET data acquisition system can effectively solve the problem that traditional PET system is vulnerable to environmental interference and difficult to correct. At the same time, the introduction of digital signal processing technology brings a variety of advantages, which is a hot spot in the design of PET instruments. In this paper, a new all-digital pulse acquisition method, multi-voltage threshold sampling (MVT), is studied, which includes the accuracy of noise, baseline and time-digital converter (TDC). And threshold setting. A method of noise processing based on MVT is proposed to obtain the energy information of pulse accurately. The effect of the actual hardware threshold number and the precision of the time digital converter on the MVT energy acquisition is simulated and simulated. The baseline correction algorithm based on MVT is implemented. It lays a foundation for the realization of PET acquisition system of MVT method. On the basis of simulation, a flash energy pulse acquisition system based on MVT method is implemented in this paper. The system has the advantages of short dead time, full digitization and easy post-correction. Based on this system, the previous simulation method is verified, and the preliminary results are obtained, which lays the foundation for the full digital energy acquisition of PET system. Finally, based on the digital small animal PET system developed by Huazhong University of Science and Technology, the energy information acquisition unit of scintillation pulse is studied and realized by making full use of the characteristics of scintillation pulse and digital signal processing technology. Under the consideration of the actual performance factors, the digital integral method is used to obtain good energy performance and meet the expected requirements.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：R310
本文编号：2265370
[Abstract]:Positron Emission Tomography (Positron Emission Tomography,) is a non-invasive imaging method that dynamically evaluates the metabolic level and biochemical reactions of various organs in living organisms by detecting the distribution of radioactive tracers in vivo. Functional activity and perfusion. As a cutting-edge technology in nuclear medicine diagnosis and research, PET has unique application value in early diagnosis, evaluation of curative effect and basic research in tumor, cardiovascular, nervous system and so on. The digital PET data acquisition system can effectively solve the problem that traditional PET system is vulnerable to environmental interference and difficult to correct. At the same time, the introduction of digital signal processing technology brings a variety of advantages, which is a hot spot in the design of PET instruments. In this paper, a new all-digital pulse acquisition method, multi-voltage threshold sampling (MVT), is studied, which includes the accuracy of noise, baseline and time-digital converter (TDC). And threshold setting. A method of noise processing based on MVT is proposed to obtain the energy information of pulse accurately. The effect of the actual hardware threshold number and the precision of the time digital converter on the MVT energy acquisition is simulated and simulated. The baseline correction algorithm based on MVT is implemented. It lays a foundation for the realization of PET acquisition system of MVT method. On the basis of simulation, a flash energy pulse acquisition system based on MVT method is implemented in this paper. The system has the advantages of short dead time, full digitization and easy post-correction. Based on this system, the previous simulation method is verified, and the preliminary results are obtained, which lays the foundation for the full digital energy acquisition of PET system. Finally, based on the digital small animal PET system developed by Huazhong University of Science and Technology, the energy information acquisition unit of scintillation pulse is studied and realized by making full use of the characteristics of scintillation pulse and digital signal processing technology. Under the consideration of the actual performance factors, the digital integral method is used to obtain good energy performance and meet the expected requirements.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：R310
【参考文献】
相关期刊论文 前1条
1 刘士涛,许咨宗,曾海宁,李辉;PSPMT基本特性的实验研究[J];核技术;2000年08期
本文编号：2265370
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