School of Information Engineering, Nanchang University, Nanchang 330031, China.
Sensors (Basel). 2020 Oct 15;20(20):5820. doi: 10.3390/s20205820.
Positron emission tomography (PET) has a wide range of applications in the treatment and prevention of major diseases owing to its high sensitivity and excellent resolution. However, there is still much room for optimization in the readout circuit and fast pulse sampling to further improve the performance of the PET scanner. In this work, a LIGHTENING® PET detector using a 13 × 13 lutetium-yttrium oxyorthosilicate (LYSO) crystal array read out by a 6 × 6 silicon photomultiplier (SiPM) array was developed. A novel sampling method, referred to as the dual time interval (DTI) method, is therefore proposed to realize digital acquisition of fast scintillation pulse. A semi-cut light guide was designed, which greatly improves the resolution of the edge region of the crystal array. The obtained flood histogram shown that all the 13 × 13 crystal pixels can be clearly discriminated. The optimum operating conditions for the detector were obtained by comparing the flood histogram quality under different experimental conditions. An average energy resolution (FWHM) of 14.3% and coincidence timing resolution (FWHM) of 972 ps were measured. The experimental results demonstrated that the LIGHTENING® PET detector achieves extremely high resolution which is suitable for the development of a high performance time-of-flight PET scanner.
正电子发射断层扫描（PET）由于其高灵敏度和出色的分辨率，在重大疾病的治疗和预防方面有广泛的应用。然而，在读取电路和快速脉冲采样方面仍有很大的优化空间，以进一步提高 PET 扫描仪的性能。在这项工作中，我们开发了一种使用 13×13 硅酸镥（LYSO）晶体阵列和 6×6 硅光电倍增管（SiPM）阵列读取的 LIGHTENING® PET 探测器。因此，提出了一种新的采样方法，称为双时间间隔（DTI）方法，以实现快速闪烁脉冲的数字采集。设计了一种半切导光管，极大地提高了晶体阵列边缘区域的分辨率。获得的洪水直方图表明，所有 13×13 个晶体像素都可以清晰地区分。通过比较不同实验条件下的洪水直方图质量，获得了探测器的最佳工作条件。测量得到的平均能量分辨率（FWHM）为 14.3%，符合时间分辨率（FWHM）为 972 ps。实验结果表明，LIGHTENING® PET 探测器实现了极高的分辨率，非常适合开发高性能的飞行时间 PET 扫描仪。
