Evaluation of a prototype small animal PET detector with depth-of-interaction encoding
Evaluation of a prototype small animal PET detector with depth-of-interaction encoding
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DOI：
10.1109/tns.2004.832905
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发表时间：
2004-08-01
影响因子：
1.8
通讯作者：
Farrell, R
中科院分区：
文献类型：
--
作者：
Burr, KC;Ivan, A;Farrell, R
我们报告了对具有交互深度 (DOI) 编码的小动物正电子发射断层扫描 (PET) 探测器原型的评估。该探测器由 8 x 8 闪烁体晶体阵列组成，通过位置敏感雪崩光电二极管 (PSAPD) 在顶部和底部读出。每个闪烁体晶体的尺寸为1.65mm×1.65mm×22.00mm，并且阵列的节距为1.75mm。 14 x 14 mm PSAPD 与紧凑的分立跨阻前置放大器耦合。 DOI 响应是通过用 511 keV 伽马射线电子准直扇形光束从侧面照射探测器模块来测量的。来自 PSAPD 角接触的信号用于识别相互作用的晶体，并且来自两个 PSAPD 的总信号的比率用于计算发生相互作用的深度 z。通过在 z 方向（垂直于扇形光束）步进晶体阵列，我们能够确定每个晶体的 DOI 分辨率。对于在 10 摄氏度下进行的测量，平均 DOI 分辨率优于 3 毫米。能量分辨率和时间分辨率（与耦合到光电倍增管的快速塑料闪烁体相比）是在相同的操作条件下获得的。 5·11 keV 时，整个阵列的平均能量分辨率为 16.6%，平均定时分辨率为 3.9 us。重要的是，探测器的性能一直保持到 PSAPD 边缘的晶体。
We report on the evaluation of a prototype small-animal positron emission tomography (PET) detector with depth-of-interaction (DOI) encoding. The detector consisted of an 8 x 8 array of scintillator crystals that were read out on the top and bottom by position sensitive avalanche photodiodes (PSAPD). Each scintillator crystal had dimensions of 1.65 mm x 1.65 mm x 22.00 mm, and the array had a pitch of 1.75 mm. The 14 x 14 mm PSAPDs were coupled to compact, discrete transimpedance preamplifiers. The DOI response was measured by illuminating the detector module from the side with an electronically collimated fan beam of 511 keV gamma rays. The signals from the corner contacts of the PSAPDs were used to identify the crystal of interaction, and the ratio of the total signals from the two PSAPDs was used to calculate the depth z at which the interaction took place. By stepping the crystal array in the z direction (perpendicular. to the fan beam), we were able to determine the DOI resolution for each individual crystal. For measurements made at 10degreesC, the average DOI resolution was better than 3 mm. Energy resolution and timing resolution (versus a fast plastic scintillator coupled to a photomultiplier tube) were made under the same operating conditions. The average energy resolution across the array was 16.6 % at 5 11 keV, and the average timing resolution was 3.9 us. Importantly, the detector performance was maintained all the way out to the crystals at the edges of the PSAPDs.