PDF(Pubmed)
Abstract：
Incorrect scatter scaling of positron emission tomography (PET) images can lead to halo artifacts, quantitative bias, or reconstruction failure. Tail-fitted scatter scaling (TFSS) possesses performance limitations in multiple cases. This study aims to investigate a novel method for scatter scaling: maximum-likelihood scatter scaling (MLSS) in scenarios where TFSS tends to induce artifacts or are observed to cause reconstruction abortion. [68Ga]Ga-RGD PET scans of nine patients were included in cohort 1 in the scope of investigating the reduction of halo artifacts relative to the scatter estimation method. PET scans of 30 patients administrated with [68Ga]Ga-uPAR were included in cohort 2, used for an evaluation of the robustness of MLSS in cases where TFSS-integrated reconstructions are observed to fail. A visual inspection of MLSS-corrected images scored higher than TFSS-corrected reconstructions of cohort 1. The quantitative investigation near the bladder showed a relative difference in tracer uptake of up to 94.7%. A reconstruction of scans included in cohort 2 resulted in failure in 23 cases when TFSS was used. The lesion uptake values of cohort 2 showed no significant difference. MLSS is suggested as an alternative scatter-scaling method relative to TFSS with the aim of reducing halo artifacts and a robust reconstruction process.
摘要：
正电子发射断层扫描（PET）图像的错误散射缩放会导致光晕伪影，定量偏差，或重建失败。尾部拟合散射缩放(TFSS)在多种情况下具有性能限制。这项研究旨在研究一种新的散射缩放方法：在TFSS倾向于诱发伪影或被观察到导致重建流产的情况下，最大似然散射缩放（MLSS）。[68Ga]九名患者的Ga-RGDPET扫描被包括在队列1中,在调查相对于散射估计方法的晕圈伪影的减少的范围内。在队列2中包括了30名给予[68Ga]Ga-uPAR的患者的PET扫描,用于在观察到TFSS整合重建失败的情况下评估MLSS的稳健性。MLSS校正图像的视觉检查得分高于队列1的TFSS校正重建。膀胱附近的定量研究显示示踪剂摄取的相对差异高达94.7％。当使用TFSS时，队列2中包含的扫描重建导致23例失败。队列2的病变摄取值没有显着差异。MLSS被建议作为相对于TFSS的替代散射缩放方法，目的是减少光晕伪影和强大的重建过程。
