José Santo Rodrigo, Salomon André, W A M de Jong Hugo, Stute Simon, Merlin Thibaut, Beijst Casper
Department of Radiotherapy, Imaging & Oncology Division, UMC Utrecht, Utrecht, The Netherlands.
Philips Research Europe, Eindhoven, The Netherlands.
EJNMMI Phys. 2025 Feb 28;12(1):17. doi: 10.1186/s40658-025-00730-x.
Scatter correction is essential for quantitative and accurate time-of-flight (TOF) PET imaging. It is implemented by an accurate scatter estimation algorithm, to calculate the statistical distribution of scattered photons among the measured coincidences. However, to our knowledge, scatter estimation algorithms that account for TOF and that are compatible with custom geometries are not available in open-source reconstruction libraries, such as CASToR and STIR. To this end, we have developed an open-source implementation of the TOF-aware single-scatter-simulation (SSS) algorithm: openSSS.
openSSS is validated on NEMA phantoms and patient data, for three PET geometries, compared to Monte-Carlo simulations and two proprietary vendor-specific reconstruction platforms. The reconstructed images have similar contrast recovery and background variability, deviating by up to 3.7%-point on contrast recovery and 1.8 on background variability and looking visually similar.
We have developed and validated an open-source scatter estimation library to complement reconstruction frameworks. By enabling vendor-independent clinical-grade reconstructions on custom scanner geometries, openSSS represents a crucial step in transparent research on quantitative PET and novel PET scanner designs.
散射校正是定量和准确的飞行时间（TOF）PET成像所必需的。它通过精确的散射估计算法来实现，以计算测量的符合事件中散射光子的统计分布。然而，据我们所知，在诸如CASToR和STIR等开源重建库中，尚无考虑TOF且与定制几何形状兼容的散射估计算法。为此，我们开发了一种飞行时间感知单散射模拟（SSS）算法的开源实现：openSSS。
与蒙特卡罗模拟和两个专有的特定供应商重建平台相比，openSSS在三种PET几何形状的NEMA体模和患者数据上得到了验证。重建图像具有相似的对比度恢复和背景变异性，对比度恢复偏差高达3.7个百分点，背景变异性偏差为1.8，视觉上看起来相似。
我们开发并验证了一个开源散射估计库，以补充重建框架。通过在定制扫描仪几何形状上实现独立于供应商的临床级重建，openSSS代表了定量PET透明研究和新型PET扫描仪设计中的关键一步。
