Fundamental preclinical research with mice to improve boron neutron capture therapy requires a prompt gamma-ray imaging detector that can chart the real-time accumulation of ¹⁰B in tumors. This study aimed to improve the spatial resolution of our previous detector, which was based on a slab-shape LaBr₃(Ce) scintillator, by changing to a pixelated 8 $\times$ 8 array scintillator.

The difference between the scintillation-light detection processes, such as Compton scattering and the photoelectron effect, affects energy resolution. This was experimentally revealed and evaluated with Monte Carlo simulations. The events caused by Compton scattering were eliminated, and our detector obtained the desired energy resolution for 511 keV gamma rays at 5.0 ± 0.4 %. The spatial resolution was evaluated using collimated gamma rays and was found to be better than that of the previous system because the scintillation light did not spread over the pixelated scintillator. As a result, the proposed detection system had the energy resolution to discriminate between 478- and 511-keV gamma rays to obtain the ¹⁰B concentration. The lateral and vertical spatial resolutions FWHM of the improved system were 5.9 mm and 5.2 mm, respectively, which were better than the value of 8.0 mm provided by the previous system to visualize the two-dimensional distribution in real time.

用小鼠进行基础临床前研究以改善硼中子捕获疗法需要一种快速的伽马射线成像探测器，该探测器可以绘制出肿瘤中¹⁰ B的实时积累图 。这项研究旨在通过将像素化为8的像素改变为平板状LaBr ₃（Ce）闪烁体，从而提高我们先前的探测器的空间分辨率。$\times$ 8个阵列闪烁体。

闪烁光检测过程之间的差异（例如康普顿散射和光电子效应）会影响能量分辨率。实验证明了这一点，并通过蒙特卡洛模拟进行了评估。消除了由康普顿散射引起的事件，我们的检测器获得了511 keV伽马射线在5.0±0.4％时所需的能量分辨率。使用准直伽马射线评估了空间分辨率，发现它比以前的系统要好，因为闪烁光不会散布在像素化闪烁体上。结果，所提出的检测系统具有的能量分辨率可以区分478keV和511keV的伽马射线，从而获得 ¹⁰B浓度。改进后的系统的横向和垂直空间分辨率FWHM分别为5.9 mm和5.2 mm，优于先前系统提供的用于实时显示二维分布的8.0 mm值。