Detection performance analysis for time-of-flight PET

In this paper, we investigate the performance of time-of-flight (TOF) PET in improving lesion detectability. We present a theoretical approach to compare lesion detectability of TOF versus non-TOF systems. Computer simulations are performed to validate the theoretical predictions. A TOF PET tomograph is simulated using the SimSET software. Images are reconstructed from list-mode data using a maximum a posteriori (MAP) method. We use a channelized Hotelling observer (CHO) to assess the detection performance. Both the receiver operating characteristic (ROC) and localization ROC (LROC) curves are compared for the TOF and non-TOF PET systems. We also study the SNR gains for TOF PET with different scatter and random fractions. Simulation results match with the theoretical predictions very well. Both results show that the TOF information improves lesion detectability and the improvement is greater with larger fractions of randoms and scatters.