The LabPET II is a new positron emission tomography technology platform designed to achieve submillimetric spatial resolution imaging using fully pixelated avalanche photodiodes-based detectors and highly integrated parallel front-end processing electronics. The detector was designed as a generic building block to develop devices for preclinical imaging of small to mid-sized animals and for clinical imaging of the human brain. The aim of this work is to assess the physical characteristics and imaging performance of the mouse version of LabPET II scanner following the NEMA NU4-2008 standard and using high resolution phantoms and in vivo imaging applications. A reconstructed spatial resolution of 0.78 mm (0.5 μ l) is measured close to the center of the radial field of view. With an energy window of 350 650 keV, the system absolute sensitivity is 1.2% and its maximum noise equivalent count rate reaches 61.1 kcps at 117 MBq. Submillimetric spatial resolution is achieved in a hot spot phantom and tiny bone structures were resolved with unprecedented contrast in the mouse. These results provide convincing evidence of the capabilities of the LabPET II technology for biomolecular imaging in preclinical research.

LabPET II 是一种新型正电子发射断层扫描技术平台，旨在使用基于全像素化雪崩光电二极管的探测器和高度集成的并行前端处理电子设备实现亚毫米空间分辨率成像。该探测器被设计为通用构建块，用于开发用于中小型动物临床前成像和人脑临床成像的设备。这项工作的目的是评估鼠标版本的 LabPET II 扫描仪的物理特性和成像性能，遵循 NEMA NU4-2008 标准，并使用高分辨率模型和体内成像应用。0.78 mm (0.5 μl ) 的重建空间分辨率) 在径向视场中心附近测量。能量窗口为350 650 keV，系统绝对灵敏度为1.2%，最大噪声等效计数率在117 MBq时达到61.1 kcps。在热点模型中实现了亚毫米级空间分辨率，并且在小鼠中以前所未有的对比度解析了微小的骨骼结构。这些结果为 LabPET II 技术在临床前研究中用于生物分子成像的能力提供了令人信服的证据。