Three-dimensional array of scintillation crystals with proper reflector arrangement for a depth of interaction detector
Three-dimensional array of scintillation crystals with proper reflector arrangement for a depth of interaction detector
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DOI：
10.1109/tns.2004.843158
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发表时间：
2003-10
影响因子：
1.8
通讯作者：
N. Orita;Hideo Murayama;Hideyuki Kawai;N. Inadama;T. Tsuda
中科院分区：
文献类型：
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作者：
N. Orita;Hideo Murayama;Hideyuki Kawai;N. Inadama;T. Tsuda
为实现高分辨率和高灵敏度的下一代正电子发射断层扫描仪（jPET-D4）提出了一种获取四层相互作用深度（DOI）信息的新方法。 jPET-D4的探测器模块是16/spl times/16/spl times/4 Gd/sub 2/SiO/sub 5/:Ce (GSO)多晶阵列，与具有大开口面积的256ch平板位置敏感光电倍增管（256ch FP-PMT）耦合。第一个对 DOI 信息进行编码的挑战是使用由 2/spl 次/2/spl 次/4 个晶体元件组成的 8/spl 次/8 个单元阵列进行的。在之前的报告中，该单元是为四层 DOI 编码而开发的。通过均匀的伽马射线照射来评价其晶体识别性能。根据 FP-PMT 多阳极输出的相对比率，将测量到的闪烁事件映射到二维 (2-D) 位置直方图上。然而，在所得的二维位置直方图中，对应于一个单元的晶体元素的峰形成一个集落，并且相邻集落之间存在较大的空间。在新方法中，反射器布置可以在多晶阵列中实现适当的光共享，从而减少了这种浪费的空间。因此，二维位置直方图上的峰谷比从 1.8:1 提高到 3.3:1。我们发现新方法也提高了能源绩效。
A new method to acquire four-layer depth of interaction (DOI) information is proposed for the next generation positron emission tomography scanner (jPET-D4) that realizes high resolution and high sensitivity. The detector module of the jPET-D4 is a 16/spl times/16/spl times/4 Gd/sub 2/SiO/sub 5/: Ce (GSO) multicrystal array coupled with a 256 ch flat panel position sensitive photomultiplier tube (256 ch FP-PMT) having large opening area. The first challenge to encode DOI information was carried out with 8/spl times/8 array of units consisted of 2/spl times/2/spl times/4 crystal elements. The unit is developed for four-layer DOI encoding in previous report. Its crystal identification performance is evaluated by uniform gamma ray irradiation. The measured scintillation events are mapped on a two-dimensional (2-D) position histogram according to the relative ratio of the multianode output of the FP-PMT. However, peaks corresponding to the crystal elements of one unit form a colony in the resultant 2-D position histogram and there is large space between adjacent colonies. In the new method, the reflector arrangement which makes proper light sharing in the multicrystal array decreases such wasted space. Consequently, peak-to-valley on the 2-D position histogram was improved to 3.3:1 from 1.8:1. We found energy performance was also enhanced by the new method.