Krishnamoorthy Srilalan, LeGeyt Benjamin, Werner Matthew E, Kaul Madhuri, Newcomer F M, Karp Joel S, Surti Suleman
Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 USA.
Department of Physics and Astronomy.
IEEE Trans Nucl Sci. 2014 Jun;61(3):1092-1098. doi: 10.1109/tns.2014.2302580.
This paper describes the design and performance of a high spatial resolution PET detector with time-of-flight capabilities. With an emphasis on high spatial resolution and sensitivity, we initially evaluated the performance of several 1.5 × 1.5 and 2.0 × 2.0 mm and 12-15 mm long LYSO crystals read out by several appropriately sized PMTs. Experiments to evaluate the impact of reflector on detector performance were performed and the final detector consisted of a 32 × 32 array of 1.5 × 1.5 × 15 mm LYSO crystals packed with a diffuse reflector and read out by a single Hamamatsu 64 channel multi-anode PMT. Such a design made it compact, modular and offered a cost-effective solution to obtaining excellent energy and timing resolution. To minimize the number of readout signals, a compact front-end readout electronics that summed anode signals along each of the orthogonal directions was also developed. Experimental evaluation of detector performance demonstrates clear discrimination of the crystals within the detector. An average energy resolution (FWHM) of 12.7 ± 2.6% and average coincidence timing resolution (FWHM) of 348 ps was measured, demonstrating suitability for use in the development of a high spatial resolution time-of-flight scanner for dedicated breast PET imaging.
本文描述了一种具有飞行时间功能的高空间分辨率正电子发射断层显像（PET）探测器的设计与性能。重点关注高空间分辨率和灵敏度，我们首先评估了几种由尺寸合适的光电倍增管（PMT）读出的1.5×1.5毫米、2.0×2.0毫米且长度为12 - 15毫米的硅酸钇镥（LYSO）晶体的性能。进行了评估反射器对探测器性能影响的实验，最终的探测器由32×32阵列的1.5×1.5×15毫米LYSO晶体组成，晶体填充有漫反射器，并由单个滨松64通道多阳极PMT读出。这种设计使其紧凑、模块化，并为获得出色的能量和时间分辨率提供了一种经济高效的解决方案。为了尽量减少读出信号的数量，还开发了一种紧凑的前端读出电子设备，该设备沿每个正交方向对阳极信号进行求和。探测器性能的实验评估表明，探测器内的晶体能够被清晰分辨。测量得到的平均能量分辨率（半高宽）为12.7±2.6%，平均符合时间分辨率（半高宽）为348皮秒，这表明该探测器适用于开发用于专用乳腺PET成像的高空间分辨率飞行时间扫描仪。
