Attenuation correction (AC) and scatter correction (SC) are essential steps for accurate PET quantification in positron emission tomography (PET)/computed tomography (CT) and PET/magnetic resonance (MR) imaging. SC with a single scatter simulation (SSS) algorithm is usually performed by employing an attenuation map using CT and MR data for AC. The purpose of this study was to evaluate the effect of SC using a SSS algorithm with CT- and MR-based attenuation maps in phantom and volunteer studies for ¹⁸F-FDG brain PET. We investigated the effect of the SC on two MR-based attenuation maps, which included a four-segmentation Dixon (soft tissue, fat, lung, and air) and a five-segmentation Model, which is Dixon plus bone, and we compared those maps with a standard CT-based attenuation map. In the phantom study, the difference in (%) recovery coefficients before and after SC for a CT-based attenuation correction (CTAC) and a MR-based attenuation correction (MRAC) were 20.36 and 21.01, respectively. The difference in the scatter fractions on the sinogram was about 2% between the CTAC and the MRAC (Dixon). In the volunteer study, the scatter fractions were 24.08 for the CT, 23.09 for the Dixon, and 23.11 for the Model. The bias in the scatter ratio image, after calculating the before and after SCs from the PET images, between the CTAC and the two MRACs was less than 1% (% MAE = 0.43 for CT-Dixon and 0.39 for CT-Model). A voxel-wise analysis of the scatter ratio before and after the SC from PET images showed no significant differences between the CTAC and the two MRACs (p > 0.05). We found that despite the different attenuation maps, the difference in the effects of the SC between the two MR and the CT attenuation maps was minimal. This implies that the SC obtained using the SSS algorithm was rarely affected by the attenuation map.

衰减校正 (AC) 和散射校正 (SC) 是在正电子发射断层扫描 (PET)/计算机断层扫描 (CT) 和 PET/磁共振 (MR) 成像中准确量化 PET 的重要步骤。使用单散射模拟 (SSS) 算法的 SC 通常通过使用衰减图来执行，该图使用 AC 的 CT 和 MR 数据。本研究的目的是使用 SSS 算法和基于 CT 和 MR 的衰减图评估 SC 在¹⁸年的体模和志愿者研究中的效果。F-FDG 脑 PET。我们研究了 SC 对两个基于 MR 的衰减图的影响，其中包括四段 Dixon（软组织、脂肪、肺和空气）和五段模型，即 Dixon 加骨骼，我们比较了这些使用基于标准 CT 的衰减图进行映射。在体模研究中，基于 CT 的衰减校正 (CTAC) 和基于 MR 的衰减校正 (MRAC) 的 SC 前后恢复系数的差异 (%) 分别为 20.36 和 21.01。CTAC 和 MRAC (Dixon) 之间正弦图上散射分数的差异约为 2%。在志愿者研究中，CT 的散射分数为 24.08，Dixon 为 23.09，模型为 23.11。在从 PET 图像计算前后 SCs 后，散射比图像中的偏差，CTAC 和两个 MRAC 之间的差异小于 1%（CT-Dixon 的 MAE 百分比 = 0.43，CT 模型的 MAE 百分比 = 0.39）。PET 图像 SC 前后散射比的体素分析显示 CTAC 和两个 MRAC 之间没有显着差异。p  > 0.05）。我们发现，尽管衰减图不同，但两个 MR 和 CT 衰减图之间 SC 的影响差异很小。这意味着使用 SSS 算法获得的 SC 很少受到衰减图的影响。