Depth-of-interaction (DOI) variability of annihilation photons is known to be a source of coincidence time resolution (CTR) degradation for fast time-of-flight–positron emission tomography detectors. An analytical model was recently proposed to explicitly include the DOI time bias separately from variance-related statistical factors, such as scintillation photon emission and photosensor jitter, in the CTR evaluation. In the present work, an experimental validation of this new model is provided. An unconventional signal readout configuration was used to magnify the DOI bias with 20 mm long LYSO:Ce crystals. In a head-to-head orientation of the crystals, simulations performed using the metric with DOI bias exhibited a much better agreement (within 21 ps) with the experimentally measured CTR of 413 8 ps full-width at half maximum, whereas simulations without DOI bias underestimated the CTR by 138 ps. The metric including DOI bias was shown to also be effective at predicting the CTR of the head-to-head setup (without DOI information) using data from a DOI-collimated experimental setup (with partial DOI information). With the development of new low-variance ultra-fast detectors, the DOI timing blur will become increasingly important and will need to be taken into account in analytical predictions and in some experimental measurements through the proposed metric.

fast灭光子的相互作用深度（DOI）变异性是快速飞行时间正电子发射断层扫描探测器的同时时间分辨率（CTR）下降的原因。最近提出了一种分析模型，在CTR评估中将DOI时间偏差与方差相关的统计因素（例如闪烁光子发射和光传感器抖动）分开明确地包括在内。在目前的工作中，提供了对该新模型的实验验证。非常规的信号读取配置用于放大20mm长的LYSO：Ce晶体的DOI偏置。在晶体的头对头方向上，使用具有DOI偏差的度量进行的模拟显示出更好的一致性（21 ps以内），与实验测得的CTR的一半（最大值）为413 8 ps。而没有DOI偏差的模拟则将CTR低估了138 ps。已显示包括DOI偏差在内的指标还可有效地使用来自DOI准直实验设置（具有部分DOI信息）的数据来预测头对头设置（没有DOI信息）的CTR。随着新的低方差超快检测器的发展，DOI定时模糊将变得越来越重要，并且在分析预测和通过所建议的度量进行的某些实验测量中都需要考虑到DOI定时模糊。