目的 探讨符合线路SPECT配置针孔准直器进行小动物高能成像的可行性。方法 ① 点源试验。将14.8 MBq的⁹⁹Tc^m、¹³¹I和¹⁸F三种核素的点源分别置于针孔准直器表面中心轴线不同距离处，采集点源图像并计算分辨率；② 小鼠成像。首先采集小鼠的⁹⁹Tc^m和¹⁸F-FDG平面图像，次日采集小鼠的¹⁸F-FDG符合线路断层融合影像。结果 ⁹⁹Tc^m的点源图像清晰、无伪影；¹³¹I和¹⁸F点源周围均存在少量透射和散射伪影，图像边缘有较明显的环形透射伪影。三种核素点源分辨率均随距离增加而下降，在距离探头30 mm位置，⁹⁹Tc^m、¹³¹I和¹⁸F的点源分辨率FWHM分别为4.3、5.2、7.4 mm，分辨率FWTM分别为7.1、10.1、14.5 mm。其中，¹⁸F分辨率FWHM为7.2 mm，优于SPECT的系统分辨率10 mm。经过模拟放大2.5倍后，小鼠的高、低能影像均较清晰，环形伪影位于有效视野之外。小鼠符合线路¹⁸F-FDG的影像不清晰。结论 在对分辨率要求不高的场合，符合线路SPECT配置低能针孔准直器进行小动物高能成像是可行的。

Objective This study was aimed to explore the feasibility of small animal high-energy imaging using coincidence SPECT (Single-Photon Emission Computerized Tomography) with a pinhole collimator. Methods First, the point sources of 14.8MBq’s three radionuclides (⁹⁹Tc^m, ¹³¹I and ¹⁸F) were placed at different distances from the central axis of the pinhole collimator respectively. Images of point sources were acquired to calculate their resolutions. Then, ⁹⁹Tc^m and ¹⁸F-FDG images of mice were acquired respectively. The coincidence images of the mouse were acquired on the second day. Results The images of ⁹⁹Tc^m point source were clear without artifacts; however, there were minor penetration and scattered artifacts in ¹³¹I and ¹⁸F images. Additionally, both images had significant circular penetration artifacts in their edges. Resolutions of ⁹⁹Tc^m, ¹³¹I and ¹⁸F were declined with the distance increased. At the distance of 30 mm from the pinhole collimator, their FWHM (Full-Widths-at-Half-Maximum) and FWTM (Full-Widths-at-Tenth-Maximum) resolutions were 4.3, 5.2, 7.4 mm and 7.1, 10.1, 14.5 mm respectively. The FWHM resolution of ¹⁸F showed advantages over the resolution of the images acquired by SPECT. After being zoomed in 2.5 times, both the high-energy and low-energy mice images were clear with the ring artifacts outside the effective field of view. Coincidence ¹⁸F-FDG images of the mouse were not clear. Conclusion The coincidence SPECT with the low-energy pinhole collimator can be used for small animal high-energy imaging if there was no restriction on the resolution of images.