Preliminary resolution performance of the prototype system for a 4-Layer DOI-PET scanner: jPET-D4
Preliminary resolution performance of the prototype system for a 4-Layer DOI-PET scanner: jPET-D4
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DOI：
10.1109/tns.2006.871901
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发表时间：
2006-06
影响因子：
1.8
通讯作者：
T. Yamaya;N. Hagiwara;T. Obi;T. Tsuda;K. Kitamura;T. Hasegawa;H. Haneishi;N. Inadama;E. Yoshida;H. Murayama
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文献类型：
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作者：
T. Yamaya;N. Hagiwara;T. Obi;T. Tsuda;K. Kitamura;T. Hasegawa;H. Haneishi;N. Inadama;E. Yoshida;H. Murayama
我们正在开发一款高性能脑部 PET 扫描仪 jPET-D4，它提供 4 层交互深度 (DOI) 信息。该扫描仪的设计不仅能实现高空间分辨率，还能利用从多层薄晶体获得的 DOI 信息实现高扫描仪灵敏度。该扫描仪有5个环，每个环有24个探测器块，每个块由1024个2.9毫米/spl次/2.9mm/spl次/7.5mm的GSO晶体组成，排列成4层16/spl次/16阵列。在此阶段，一对探测器块和重合电路已组装成实验原型龙门架。在本文中，作为初步实验，我们使用原型系统研究了 jPET-D4 的空间分辨率性能。首先，根据滤波反投影重建图像测量空间分辨率。为了避免图像重建中的系统误差并降低计算成本，我们应用了 DOI 压缩（DOIC）方法，然后采用我们之前提出的最大似然期望最大化。研究了背景噪声和分辨率之间的权衡特性，因为只有在避免增强噪声的情况下才有可能提高空间分辨率。实验结果表明，jPET-D4 在视场范围内实现了优于 3 mm 的空间分辨率。
We are developing a high-performance brain PET scanner, jPET-D4, which provides 4-layer depth-of-interaction (DOI) information. The scanner is designed to achieve not only high spatial resolution but also high scanner sensitivity with the DOI information obtained from multi-layered thin crystals. The scanner has 5 rings of 24 detector blocks each, and each block consists of 1024 GSO crystals of 2.9 mm/spl times/2.9 mm/spl times/7.5 mm, which are arranged in 4 layers of 16/spl times/16 arrays. At this stage, a pair of detector blocks and a coincidence circuit have been assembled into an experimental prototype gantry. In this paper, as a preliminary experiment, we investigated the performance of the jPET-D4's spatial resolution using the prototype system. First, spatial resolution was measured from a filtered backprojection reconstructed image. To avoid systematic error and reduce computational cost in image reconstruction, we applied the DOI compression (DOIC) method followed by maximum likelihood expectation maximization that we had previously proposed. Trade-off characteristics between background noise and resolution were investigated because improved spatial resolution is possible only when enhanced noise is avoided. Experimental results showed that the jPET-D4 achieves better than 3 mm spatial resolution over the field-of-view.