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目的:探讨贝叶斯正则化似然(BPL)重建技术对n 18F-脱氧葡萄糖(FDG) PET/CT正常组织代谢参数及图像质量的影响。n 方法:回顾性分析2019年3月至2019年6月间烟台毓璜顶医院60例肿瘤患者[男29例，女31例，年龄24~89(60.4±15.2)岁]的PET/CT体部检查数据，将PET图像按照有序子集最大期望值迭代法(OSEM)、飞行时间(TOF)＋点扩散函数(PSF)和BPL(β值＝350)3种重建技术进行重建，分别于右肺上叶、肝脏右后叶、主动脉根部和腰椎勾画感兴趣体积(VOI)，测量VOI代谢参数[包括平均标准摄取值(SUVn mean)、最大标准摄取值(SUVn max)、瘦体质量标准摄取值(SUV)峰值(SULn peak)、SUV标准差(SUVn SD)]，并计算信噪比(SNR)，分析SNR变化率(%ΔSNR)与体质指数(BMI)的关系。采用单因素方差分析、最小显著差异n t检验和Pearson相关分析数据。n 结果:3种重建技术的正常肺、主动脉、肝脏及腰椎的SUVn mean及SULn peak差异均无统计学意义(n F值：0.04~1.95，均n P>0.05)。BPL组正常肺、主动脉、肝脏和腰椎的SUVn max(1.14±0.82、2.13±0.37、2.95±0.50和2.76±0.87)较TOF＋PSF组(1.56±0.61、2.99±0.75、4.32±0.94和4.05±1.48)和OSEM组(1.51±0.67、3.00±0.70、4.45±1.12和3.81±1.06)明显降低(n F值：20.59~52.24，均n P<0.001)；SUVn SD(0.13±0.07、0.20±0.05、0.26±0.06和0.38±0.17)较TOF＋PSF组(0.24±0.11、0.43±0.11、0.58±0.15和0.67±0.21)和OSEM组(0.21±0.09、0.42±0.10、0.58±0.14和0.63±0.20)也明显降低(n F值：24.46~124.95，均n P<0.001)；而SNR(4.67±1.34、7.74±2.22、8.17±1.77和4.45±1.22)则明显高于TOF＋PSF组(2.54±0.72、3.55±0.82、3.77±0.91和2.49±0.69)和OSEM组(2.65±0.64、3.67±0.80、3.75±0.87和2.60±0.67；n F值：83.04~247.73，均n P0.05)。BPL重建组SNR随着BMI的增加而增加，且BMI<25 kg/mn 2和BMI≥30 kg/mn 2组之间主动脉SNR(7.07±2.21和9.67±2.26)和肝脏SNR(7.75±1.85和9.32±0.70)差异有统计学意义(n F值：3.46、4.19，均n P<0.05)。BPL重建后，OSEM和TOF＋PSF组肺、主动脉、肝脏和腰椎的%ΔSNR与BMI呈正相关(n r值：0.042~0.354，均n P0.05). The SUVn max in lung, aorta, liver and lumbar vertebra of BPL reconstruction (1.14±0.82, 2.13±0.37, 2.95±0.50 and 2.76±0.87) was significantly lower than those of TOF+ PSF (1.56±0.61, 2.99±0.75, 4.32±0.94 and 4.05±1.48) and OSEM (1.51±0.67, 3.00±0.70, 4.45±1.12 and 3.81±1.06) reconstructions (n F values: 20.59-52.24, all n P<0.001) and SUVn SD (0.13±0.07, 0.20±0.05, 0.26±0.06, 0.38±0.17) was also significantly lower than those of TOF+ PSF (0.24±0.11, 0.43±0.11, 0.58±0.15, 0.67±0.21) and OSEM (0.21±0.09, 0.42±0.10, 0.58±0.14, 0.63±0.20) reconstructions (n F values: 24.46-124.95, all n P<0.001), while the SNR (4.67±1.34, 7.74±2.22, 8.17±1.77, 4.45±1.22) was significantly higher than those of TOF+ PSF (2.54±0.72, 3.55±0.82, 3.77±0.91, 2.49±0.69) and OSEM (2.65±0.64, 3.67±0.80, 3.75±0.87, 2.60±0.67) reconstructions (n F values: 83.04-247.73, all n P0.05). In BPL group, SNR increased with the increase of BMI, and there were statistically differences of aortic SNR (7.07±2.21n vs 9.67±2.26) and liver SNR (7.75±1.85 n vs 9.32±0.70) between BMI<25 kg/mn 2 and BMI≥30 kg/mn 2 (n F values: 3.46 and 4.19, both n P<0.05). Positive correlations were found between %ΔSNR of lung, aorta, liver and lumbar vertebra in OSEM and TOF+ PSF and BMI (n r value: 0.042-0.354, all n P<0.05).n Conclusion:In background tissues, BPL algorithm has no significant impact on absolute quantification compared with OSEM and TOF + PSF reconstruction methods but it can significantly improve SNR, especially for the patients with large body weight.